Trending in endo & adenomyosis research

IMPORTANCE: Endometriosis is a chronic, estrogen-dependent, inflammatory disease defined by endometrial-like tissue (lesions) outside the uterine lining. It affects up to 10% of women worldwide, and 9 million women in the US, during reproductive years. OBSERVATIONS: Endometriosis has varying clinical presentations; however, 90% of people with endometriosis report pelvic pain, including dysmenorrhea, nonmenstrual pelvic pain, and dyspareunia, and 26% report infertility. Risk factors for endometriosis include younger age at menarche, shorter menstrual cycle length, lower body mass index, nulliparity, and congenital obstructive müllerian anomalies such as obstructed hemivagina. Although definitive diagnosis requires surgical visualization of lesions, a suspected clinical diagnosis can be made based on symptoms, supported by physical examination findings and imaging with transvaginal ultrasound and/or pelvic magnetic resonance imaging; normal physical examination and imaging do not exclude the diagnosis. The diagnosis is often delayed, averaging 5 to 12 years after onset of symptoms, with most women consulting 3 or more clinicians prior to diagnosis. Hormonal medications, such as combined oral contraceptives and progestin-only options, are first-line treatment and should be offered to symptomatic premenopausal women who do not currently desire pregnancy. In a network meta-analysis (n = 1680, 15 clinical trials), hormonal treatments including combined oral contraceptives, progestins, and gonadotropin-releasing hormone (GnRH) agonists led to clinically significant pain reduction compared with placebo, with mean differences ranging between 13.15 and 17.6 points (0-100 visual analog scale) with little difference in effectiveness among options. However, 11% to 19% of individuals with endometriosis have no pain reduction with hormonal medications and 25% to 34% experience recurrent pelvic pain within 12 months of discontinuing hormonal treatment. Surgical removal of lesions, usually with laparoscopy, should be considered if first-line hormonal therapies are ineffective or contraindicated. Second-line hormone therapies include GnRH agonists and antagonists, and third-line treatments include aromatase inhibitors. Hysterectomy with surgical removal of lesions may be considered when initial treatments are ineffective. However, approximately 25% of patients who undergo hysterectomy for endometriosis experience recurrent pelvic pain and 10% undergo additional surgery, such as lysis of adhesions, to treat pain. CONCLUSIONS AND RELEVANCE: Endometriosis is a common cause of pelvic pain affecting approximately 10% of reproductive-age women. Hormonal suppression with combined estrogen-progestin contraceptives or progestins is first-line treatment for women who are not seeking immediate pregnancy. Surgical removal of endometriosis lesions may be performed if hormonal therapies are ineffective or contraindicated, and hysterectomy may be considered if medical treatments and surgical removal of lesions do not relieve symptoms.

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Endometriosis affects approximately 190 million women and people assigned female at birth worldwide. It is a chronic, inflammatory, gynecologic disease marked by the presence of endometrial-like tissue outside the uterus, which in many patients is associated with debilitating painful symptoms. Patients with endometriosis are also at greater risk of infertility, emergence of fatigue, multisite pain, and other comorbidities. Thus, endometriosis is best understood as a condition with variable presentation and effects at multiple life stages. A long diagnostic delay after symptom onset is common, and persistence and recurrence of symptoms despite treatment is common. This review discusses the potential genetic, hormonal, and immunologic factors that lead to endometriosis, with a focus on current diagnostic and management strategies for gynecologists, general practitioners, and clinicians specializing in conditions for which patients with endometriosis are at higher risk. It examines evidence supporting the different surgical, pharmacologic, and non-pharmacologic approaches to treating patients with endometriosis and presents an easy to adopt step-by-step management strategy. As endometriosis is a multisystem disease, patients with the condition should ideally be offered a personalized, multimodal, interdisciplinary treatment approach. A priority for future discovery is determining clinically informative sub-classifications of endometriosis that predict prognosis and enhance treatment prioritization.

Endometriosis is a complex disease, which is defined by abnormal growth of endometrial tissue outside the uterus. It affects about 10% of women of reproductive age all over the world. Endometriosis causes symptoms that notably worsen patient's well-being-such as severe pelvic pain, dysfunction of the organs of pelvic cavity, infertility and secondary mental issues. The diagnosis of endometriosis is quite often delayed because of nonspecific manifestations. Since the disease was defined, several different pathogenetic pathways have been considered, including retrograde menstruation, benign metastasis, immune dysregulation, coelomic metaplasia, hormonal disbalance, involvement of stem cells and alterations in epigenetic regulation, but the true pathogenesis of endometriosis remains poorly understood. The knowledge of the exact mechanism of the origin and progression of this disease is significant for the appropriate treatment. Therefore, this review reports the main pathogenetic theories of endometriosis based on current studies.

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Pelvic endometriosis is a complex syndrome characterized by an estrogen-dependent chronic inflammatory process that affects primarily pelvic tissues, including the ovaries. It is caused when shed endometrial tissue travels retrograde into the lower abdominal cavity. Endometriosis is the most common cause of chronic pelvic pain in women and is associated with infertility. The underlying pathologic mechanisms in the intracavitary endometrium and extrauterine endometriotic tissue involve defectively programmed endometrial mesenchymal progenitor/stem cells. Although endometriotic stromal cells, which compose the bulk of endometriotic lesions, do not carry somatic mutations, they demonstrate specific epigenetic abnormalities that alter expression of key transcription factors. For example, GATA-binding factor-6 overexpression transforms an endometrial stromal cell to an endometriotic phenotype, and steroidogenic factor-1 overexpression causes excessive production of estrogen, which drives inflammation via pathologically high levels of estrogen receptor-β. Progesterone receptor deficiency causes progesterone resistance. Populations of endometrial and endometriotic epithelial cells also harbor multiple cancer driver mutations, such as KRAS, which may be associated with the establishment of pelvic endometriosis or ovarian cancer. It is not known how interactions between epigenomically defective stromal cells and the mutated genes in epithelial cells contribute to the pathogenesis of endometriosis. Endometriosis-associated pelvic pain is managed by suppression of ovulatory menses and estrogen production, cyclooxygenase inhibitors, and surgical removal of pelvic lesions, and in vitro fertilization is frequently used to overcome infertility. Although novel targeted treatments are becoming available, as endometriosis pathophysiology is better understood, preventive approaches such as long-term ovulation suppression may play a critical role in the future.

(No abstract on file for this paper.)

Endometriosis, which affects approximately 10% of women of reproductive age, is a complex inflammatory disease with significant immune system disturbances caused by an inadequate immune response to retrograde menstruation and leading to the establishment of immune evasion mechanisms by ectopic tissue. This review provides an analysis of the immunopathogenetic mechanisms of endometriosis based on 198 high-quality publications selected from 1,209 potentially relevant articles in the PubMed, Scopus, Web of Science, and Google Scholar databases for the period 1927-2025. The study revealed that endometriosis is associated with profound alterations in both innate and adaptive immunity. Key pathogenetic mechanisms include macrophage dysfunction with a shift to the M2 phenotype, reduced cytotoxic activity of NK cells, complement system activation with proinflammatory and proangiogenic effects, a predominant Th2 response with an increase in Treg cells, and B-lymphocyte activation with autoantibody production. The cytokine profile is characterized by a concurrent increase in both pro-inflammatory mediators (IL-1β, IL-6, TNF-α) and immunosuppressive factors (IL-10, TGF-β). The complement system contributes to pathogenesis through C3a/C5a-mediated inflammation, angiogenesis promotion, and interactions with dysbiotic endometrial microbiota. Different forms of endometriosis have specific immunological features: ovarian endometriosis combines local immunosuppression with systemic inflammation, adenomyosis is characterized by pro-inflammatory changes with a Treg cell deficiency, and deep infiltrating endometriosis is distinguished by the activation of the IDO1/COX-2/MMP-9 signaling pathway and complement-mediated tissue destruction. Understanding the specifics of immunopathogenesis opens new avenues for developing targeted immunotherapy, which may include modulating immune cell functions, using cytokine inhibitors, blocking immune checkpoints, and employing nanotechnological approaches.

INTRODUCTION: No prior study of endometriosis has investigated the psychological impact of having asymptomatic endometriosis versus endometriosis with pelvic pain in a systematic way. This study aimed at examining the impact of endometriosis on quality of life, anxiety and depression by comparing asymptomatic endometriosis, endometriosis with pelvic pain, and healthy, pain-free controls. The psychological impact of different types of endometriosis pain was also tested. METHODS: One hundred and ten patients with surgically diagnosed endometriosis (78 with pelvic pain and 32 without pain symptoms) and 61 healthy controls completed two psychometric tests assessing quality of life, anxiety and depression. Endometriosis participants indicated on a numerical rating scale the intensity of four types of pain (dysmenorrhea, dyspareunia, non-menstrual pelvic pain and dyschezia). RESULTS: Endometriosis patients with pelvic pain had poorer quality of life and mental health as compared with those with asymptomatic endometriosis and the healthy controls. No significant differences were found between asymptomatic endometriosis and the control group. Dysmenorrhea had significant effects only on physical quality of life; non-menstrual pelvic pain affected all the variables; no significant effects were found for dyspareunia and dyschezia. CONCLUSIONS: Pain significantly affects women's experience of endometriosis. The medical treatment of endometriosis with pain may not be sufficient and psychological intervention is recommended.

Endometriosis, an estrogen-dependent chronic inflammatory disease characterized by the growth of endometrium-like tissues outside the uterine cavity, affects 10% of reproductive-age women. Although the pathogenesis of endometriosis is uncertain, it is widely accepted that retrograde menstruation results in ectopic endometrial tissue implantation. Given that not all women with retrograde menstruation develop endometriosis, immune factors have been hypothesized to affect the pathogenesis of endometriosis. In this review, we demonstrate that the peritoneal immune microenvironment, including innate immunity and adaptive immunity, plays a central role in the pathogenesis of endometriosis. Current evidence supports the fact that immune cells, such as macrophages, natural killer (NK) cells, dendritic cells (DCs), neutrophils, T cells, and B cells, as well as cytokines and inflammatory mediators, contribute to the vascularization and fibrogenesis of endometriotic lesions, accelerating the implantation and development of ectopic endometrial lesions. Endocrine system dysfunction influences the immune microenvironment through overexpressed estrogen and progesterone resistance. In light of the limitations of hormonal therapy, we describe the prospects for potential diagnostic biomarkers and nonhormonal therapy based on the regulation of the immune microenvironment. Further studies are warranted to explore the available diagnostic biomarkers and immunological therapeutic strategies for endometriosis.

Understanding the pathophysiology of endometriosis is changing our diagnosis and treatment. Endometriosis lesions are clones of specific cells, with variable characteristics as aromatase activity and progesterone resistance. Therefore the GE theory postulates GE incidents to start endometriosis, which thus is different from implanted endometrium. The subsequent growth in the specific environment of the peritoneal cavity is associated with angiogenesis, inflammation, immunologic changes and bleeding in the lesions causing fibrosis. Fibrosis will stop the growth and lesions look burnt out. The pain caused by endometriosis lesions is variable: some lesions are not painful while other lesions cause neuroinflammation at distance up to 28 mm. Diagnosis of endometriosis is made by laparoscopy, following an experience guided clinical decision, based on history, symptoms, clinical exam and imaging. Biochemical markers are not useful. For deep endometriosis, imaging is important before surgery, notwithstanding rather poor predictive values when confidence limits, the prevalence of the disease and the absence of stratification of lesions by size, localization and depth of infiltration, are considered. Surgery of endometriosis is based on recognition and excision. Since the surrounding fibrosis belongs to the body with limited infiltration by endometriosis, a rim of fibrosis can be left without safety margins. For deep endometriosis, this results in a conservative excision eventually with discoid excision or short bowel resections. For cystic ovarian endometriosis superficial destruction, if complete, should be sufficient. Understanding pathophysiology is important for the discussion of early intervention during adolescence. Considering neuroinflammation at distance, the indication to explore large somatic nerves should be reconsidered. Also, medical therapy of endometriosis has to be reconsidered since the variability of lesions results in a variable response, some lesions not requiring estrogens for growth and some being progesterone resistant. If the onset of endometriosis is driven by oxidative stress from retrograde menstruation and the peritoneal microbiome, medical therapy could prevent new lesions and becomes indicated after surgery.

Endometriosis is a chronic, inflammatory disease affecting more than 170 million women worldwide and up to 10% of women of reproductive age. As a consequence of inflammatory reaction and infiltration of anatomic structures, endometriosis can cause "pain symptoms" including dysmenorrhea, dyspareunia, dyschezia, dysuria, and chronic pelvic pain. In this review, we summarized the impact of endometriosis on quality of life in all its aspects including sexual life, work, and social relationships. The data research was conducted using web-based search engines and/or various electronic research databases querying for all articles related to endometriosis and quality of life from the inception of the database up to February 2020. Endometriosis has not only physical but also psychological effects, causing depression, anxiety, and compromising social relationships. Furthermore, endometriosis negatively impacts sexual life and social relationships. At last, the economic burden of endometriosis should not be underestimated, both individually and for the community, as this pathology leads to a loss of productivity at work and large use of health resources. Thus, endometriosis-related symptoms control women's lives compromising the quality of life in all aspects. In this review, we summarized the impact of endometriosis on various aspects of women's lives.

Adenomyosis is a common disorder of the uterus, and is associated with an enlarged uterus, heavy menstrual bleeding (HMB), pelvic pain, and infertility. It is characterized by endometrial epithelial cells and stromal fibroblasts abnormally found in the myometrium where they elicit hyperplasia and hypertrophy of surrounding smooth muscle cells. While both the mechanistic processes and the pathogenesis of adenomyosis are uncertain, several theories have been put forward addressing how this disease develops. These include intrinsic or induced (1) microtrauma of the endometrial-myometrial interface; (2) enhanced invasion of endometrium into myometrium; (3) metaplasia of stem cells in myometrium; (4) infiltration of endometrial cells in retrograde menstrual effluent into the uterine wall from the serosal side; (5) induction of adenomyotic lesions by aberrant local steroid and pituitary hormones; and (6) abnormal uterine development in response to genetic and epigenetic modifications. Dysmenorrhea, HMB, and infertility are likely results of inflammation, neurogenesis, angiogenesis, and contractile abnormalities in the endometrial and myometrial components. Elucidating mechanisms underlying the pathogenesis of adenomyosis raise possibilities to develop targeted therapies to ameliorate symptoms beyond the current agents that are largely ineffective. Herein, we address these possible etiologies and data that support underlying mechanisms.

This review emphasizes the participation of estrogen and inflammation in the development of endometriosis. A feedback cycle in which prostaglandins and aromatase activity are prominent allows for the persistence of endometriotic tissue. Knowledge of this cycle has important implications for the treatment of endometriosis.

The IDEA (International Deep Endometriosis Analysis group) statement is a consensus opinion on terms, definitions and measurements that may be used to describe the sonographic features of the different phenotypes of endometriosis. Currently, it is difficult to compare results between published studies because authors use different terms when describing the same structures and anatomical locations. We hope that the terms and definitions suggested herein will be adopted in centers around the world. This would result in consistent use of nomenclature when describing the ultrasound location and extent of endometriosis. We believe that the standardization of terminology will allow meaningful comparisons between future studies in women with an ultrasound diagnosis of endometriosis and should facilitate multicenter research. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd. Enfoque sistemático para la evaluación ecográfica de la pelvis en mujeres con posible endometriosis, incluyendo términos, definiciones y mediciones: una opinión consensuada del Grupo Internacional de Análisis de la Endometriosis Profunda La declaración del Grupo Internacional de Análisis de la Endometriosis Profunda (IDEA, por sus siglas en inglés) es una opinión basada en un consenso sobre los términos, definiciones y medidas que se pueden utilizar para describir las características ecográficas de los distintos fenotipos de la endometriosis. Actualmente es difícil comparar los resultados entre los estudios publicados porque los autores utilizan términos diferentes para describir las mismas estructuras y localizaciones anatómicas. Esperamos que los términos y definiciones propuestas en este documento se adopten en centros de investigación de todo el mundo. Esto resultaría en un uso uniforme de la nomenclatura para describir la ubicación y el alcance de la endometriosis en la evaluación ecográfica. Creemos que la normalización de la terminología permitirá realizar comparaciones significativas entre futuros estudios de mujeres con diagnóstico de endometriosis mediante ecografía y debería facilitar la investigación entre múltiples centros de investigación. Endometriosis is a common gynecological problem, affecting approximately 5% of women1. The disease can be found in many sites throughout the pelvis, in particular the ovaries, pelvic peritoneum, pouch of Douglas (POD), rectum, rectosigmoid, rectovaginal septum (RVS), uterosacral ligaments (USLs), vagina and urinary bladder. Correct site-specific diagnosis is fundamental in defining the optimal treatment strategy for endometriosis. Non-invasive imaging methods are required to map accurately the location and extent of endometriotic lesions. The recent consensus statement produced by the World Endometriosis Society recommended the establishment of centers of expertise for the management of higher-stage disease2. This recommendation requires a reliable preoperative system of triage which enables immediate understanding of the location and severity of disease. Increasingly, endometriosis is being managed medically and surgery can be avoided or delayed in a growing proportion of cases. Transvaginal sonography (TVS) is the first-line imaging technique in the diagnosis of pelvic endometriosis and in particular for deep infiltrating endometriosis (DIE)3. It is important to note, however, that there is substantial heterogeneity in the reported sensitivity and specificity of TVS with regard to detection of DIE, irrespective of its location4, 5. Adding ultrasound examination by an experienced operator to history and pelvic examination improves the accuracy of diagnosis of pelvic endometriosis6, 7. In their meta-analysis, Hudelist et al.8 concluded that TVS with or without the use of prior bowel preparation is an accurate test for non-invasive, presurgical detection of DIE of the rectosigmoid. Although the diagnostic performance of ultrasound for detecting DIE reported by individual units is excellent for certain anatomical locations9-11, the lack of standardized definitions in the sonographic classification and diagnosis of DIE is a general cause for concern. This lack of uniformity when classifying anatomical location and extent of disease contributes to the considerable variation in the reported diagnostic accuracy of TVS in the diagnosis of endometriosis. The aim of this consensus opinion is to ensure that the ultrasound examination of a woman with potentially underlying endometriosis is performed in a standardized manner, that the measurement of endometriotic lesions is standardized and that the terminology used when describing the location of DIE and the sonographic features of DIE and other manifestations of endometriosis (endometriomas, adenomyosis, pelvic adhesions) is uniform. This consensus opinion should be useful in clinical practice as well as in research. We believe that careful definition of ultrasound-detected DIE will facilitate interpretation of research and lead to improved clinical care. This work is based on the opinion of a panel of clinicians, gynecological sonologists, advanced laparoscopic surgeons and radiologists (International Deep Endometriosis Analysis (IDEA) group) with expertise in diagnosis and management of endometriosis. Criteria used to invite the experts to participate in this consensus process included their having significant peer-reviewed publications in the field of diagnosis and management of endometriosis. An initial statement was presented in 2011 at the ISUOG congress in Copenhagen12, incorporating several suggestions from all participants. A first draft was written in December 2014 by a joint effort of the two first authors (S.G. and G.C.) and sent to all coauthors. All coauthors had the opportunity to comment within a fixed time limit. Reply was mandatory for coauthorship. Taking all comments into account, a revised draft was then sent to all coauthors. In case of conflicting opinions, a consensus was proposed after discussion between the two first authors and the last author (D.T.). This pathway was repeated until a consensus between all authors was reached. The consensus also included ultrasound images/videos and schematic drawings to illustrate the text. After 13 revisions, the manuscript was deemed ready for submission. In addition to terms, definitions and measurements to describe the sonographic features of DIE, adhesions, adenomyosis and endometriomas, this consensus opinion includes recommendations regarding how to take a history, how to perform a clinical examination, how to perform an ultrasound examination and which ultrasound modality to use when examining patients with suspected or known endometriosis. DIE anatomical locations in this consensus were modified from Chapron's anatomical distribution of pelvic DIE13. A detailed clinical history should be taken for all women with suspected endometriosis, with particular emphasis on symptoms which could be attributed to endometriosis14, 15. The following should be noted specifically: age; height; weight; ethnic origin; parity; bleeding pattern (regular, irregular or absent); last menstrual period; previous surgery for endometriosis (type, effect); previous myomectomy or Cesarean delivery (these entail increased risk of DIE in the bladder); family history of endometriosis; previous non-surgical treatment for endometriosis (type, duration, effect); subfertility including duration of subfertility; treatment for infertility and outcome of fertility treatment; pain (dysmenorrhea, dyspareunia, dysuria, dyschezia, chronic pelvic pain); hematochezia and/or hematuria. The onset and duration of symptoms should be noted and, if possible, the intensity of the pain recorded by letting the patient use a visual analog scale or investigating it with a 0–10 narrative numeric rating scale. A pelvic examination should be performed either before or after the pelvic ultrasound scan, with the aim of defining the presence or absence of vaginal and/or low rectal endometriosis7. The pelvic examination should include speculum examination (direct visualization of vaginal or cervical DIE) and vaginal palpation. Mobility, fixation and/or tenderness of the uterus should be evaluated carefully. Site-specific tenderness in the pelvis should also be evaluated. The purpose of performing an ultrasound examination in a woman with suspected endometriosis is to try to explain underlying symptoms, map the disease location and assess the severity of disease prior to medical therapy or surgical intervention. Various ultrasound approaches have been published, but to date none has been externally validated16, 17. We propose four basic sonographic steps when examining women with suspected or known endometriosis, as shown in Figure 1. Note that these steps can be adopted in this or any order as long as ALL four steps are performed to confirm/exclude the different forms of endometriosis. Using TVS as the first-line imaging tool, the operator should examine the uterus and the adnexa. The mobility of the uterus should be evaluated: normal, reduced or fixed (‘question mark sign’)18. Sonographic signs of adenomyosis should be searched for and described using the terms and definitions published in the Morphological Uterus Sonographic Assessment consensus opinion19. The presence or absence of endometriomas (Figure S1a), their size, measured systematically in three orthogonal planes (see ‘Measurement of lesions’, below), the number of endometriomas and their ultrasound appearance should be noted20. The sonographic characteristics of any endometrioma should be described using the International Ovarian Tumor Analysis terminology21. An atypical endometrioma (Figure S1b) is defined as a unilocular-solid mass with ground glass echogenicity with a papillary projection, a color score of 1 or 2 and no flow inside the papillary projection20. Ovarian endometriomas are associated frequently with other endometriotic lesions, such as adhesions and The (Figure that there are pelvic bowel and endometriosis are in women with without and may in in which case can be with an on ultrasound examination (Figure presence of other endometriotic lesions may facilitate a diagnosis of endometrioma in and the risk of The is to for sonographic site-specific tenderness and fixed The presence of the of endometriosis and between the uterus and can assess if the is fixed to the uterus to the pelvic or to the The presence of adhesions can also be suspected on with the and/or with the the or the uterus to be fixed to structures and/or there is pelvic of may be between the or without and the uterus or the of the there are endometriomas or pelvic endometriosis, the are frequently in the disease may the and of the by endometriotic or adhesions may also a a may these and should be searched for and The is to assess the of the using the In order to assess the when the uterus is (Figure is the using the to the the of the and vaginal the rectal the is for this location The then the in order to the uterus between the and the is in the other to assess the bowel the of the it the is also in this the is found to be in of these anatomical and the is recorded as being on TVS it is that either the rectal or the the or the at of the locations has a then the is recorded as and describing the in a uterus is different (Figure is the with the to the the the the is to be for this location The then the in order to the uterus between the and is in the other to assess the the it the is also to be in this long as the is found to be in of these anatomical the and the the is recorded as The is to for DIE in the and assess the the is in the of the endometriosis is suspected on the of symptoms, patients should be to their before the ultrasound A of the of the and detection and of endometriotic the is in the of the vagina and the vagina to allow 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is between the and of the operator the the the then the is and the is as the the then the is and the is as (Figure in the pelvic are in of women with a previous Cesarean and are a of pelvic The should be using the The can be found by the in the and the the pelvic The of the is and its to it the and then to the pelvic and to the of the of the common It is to for to as this as long with a from the of the the common of the to endometriosis is by either or and the from the to the should be measured (Figure of the at the time of surgery is important in all in which is In all women with DIE, a of the to for is because the of endometriotic lesions in the urinary may be and women with DIE the may be The of should be and using ultrasound with of should be for of a to of to et the common sites of DIE in the vaginal and Sonographic of the should aim at the and anatomical location of DIE affecting these DIE lesions as of the of the bowel or or as which may in and have or irregular studies have defined the TVS diagnosis of DIE in the as absence of the appearance of the between the vagina and to the presence of a DIE have used the terms and DIE to describe DIE in the The is an individual anatomical with a DIE DIE in the rectovaginal The rectovaginal includes the the and the there is in the definition of DIE in the DIE has been described as endometriotic lesions which the and the vaginal with into the have used the to describe which the with into the vagina and/or endometriosis is We propose that of the should be suspected when a DIE is on TVS in the rectovaginal the the of the of the the (Figure DIE is (Figure DIE is an of vaginal (Figure rectal (Figure or vaginal and rectal (Figure The use of improves the detection of vaginal and The of the DIE should be recorded in three orthogonal planes and the between the of the and the should be This should be the DIE is in the vagina or in the rectum, or the and lesions, when managed are associated with including We propose that of the vaginal and/or vaginal should be suspected when a DIE is on TVS in the rectovaginal the the of the of the of the pouch of and the the of the of the the in Figure vaginal or endometriosis is suspected if the vaginal is or if a is found in the of the vaginal (Figure The may be or with or without (Figure and there may or may be the Figure is an ultrasound vaginal The of the vaginal DIE should be measured in three orthogonal or when DIE lesions in the vaginal into the rectal (Figure the of the DIE in the rectal is the same as the in the vaginal (Figure is a but between these two of the lesions are the of the and are on are on ultrasound (Figure DIE lesions can be in the of the uterus (Figure these are by the in the vaginal in the in the and then the to the are to be by DIE when a with or irregular is within the the The may be or may be of a into the vagina or into other The of a can be measured in the at the of the on the that the can be from structures (Figure In the DIE the is at the (Figure it is as a of the The of the DIE should be recorded in three orthogonal DIE the rectum, and/or all of which can be using Figure a schematic of a DIE within the DIE can take the of an or can be lesions affecting the same and/or lesions affecting several bowel and/or Although TVS can be used to rectal DIE (Figure there are no published its and imaging can be used to and bowel bowel endometriosis is defined as the presence of and in the bowel at the this and This results in of the bowel and of the bowel rectal can be on the rectal is as a the is with the and by a the is and the is (Figure DIE on TVS as a of the or as with or without (Figure with The of bowel should be described to Figure bowel lesions are and in a or a is noted at a (Figure The appearance of the of the or is by a of with and adhesions, in the or (Figure the of these lesions can We propose that bowel DIE lesions noted on TVS be described to the of the or in which with DIE lesions the of the of the on the being as rectal DIE lesions, this being as at rectal DIE lesions, at the of the being as DIE lesions and the of the being as DIE lesions (Figure The of the rectal and/or DIE should be recorded in three orthogonal planes and the between the of the and the should be measured using bowel DIE may the bowel at different other bowel lesions should be for when there is a DIE affecting the (Figure or rectosigmoid. that rectal DIE lesions may be associated with a in of diagnosis of has been in this The can be as or on or or a an experienced operator can the of in an it is at the of the uterus and/or and, in a it is at the uterus and/or We propose that endometrioma and DIE should be measured systematically in three orthogonal to the and (Figure This of in three planes to DIE lesions in the and rectosigmoid. in of endometriosis in the it is important to the between the and a DIE which a the can be by either or the is the of the should be at this and the other at the for measurement (Figure In of bowel DIE lesions the of the bowel from to should be measured (Figure It is important to be that the within DIE lesions can result in an of the of the and an of the of the (Figure This has been described as the on and can also be noted on In of DIE lesions in the bowel or it is important to the between the and the (Figure It is to the from the to the bowel using the into the and the of the the endometriotic can be on the at the of the and a used to the from the on the to the of the when the has been TVS can also be used to the from the to the of the bowel there are bowel lesions, then the between the and the bowel is Figure 13 an of and locations for deep infiltrating endometriosis. Although well in the of no have been reported for the of color in the of endometriotic lesions in the are is useful in the diagnosis between DIE in the bowel and rectal (Figure and propose that color be used as an modality in the of DIE lesions of the ultrasound examination is performed with or without an between the and the vaginal with an of the the of any tenderness experienced the TVS requires ultrasound of a into the the is well and of the of of the bowel (Figure TVS with of into the A is used at its a that with approximately to of the that is into the vagina using a The an between the and the structures the vagina and that the vaginal This visualization of the vaginal and vaginal In order to perform ultrasound is into the vaginal using a before of the The an a of the structures of the (Figure The be into the there are no or in the The is that the in with the the of when the into the is taken to ensure that the is into the vagina that the the In published no woman required any of the with can be used if if TVS is or for if the woman is In of was useful in the diagnosis of locations of DIE without such as DIE in the vagina or however, of the mobility of pelvic it allow of are no studies that ultrasound ultrasound in the detection or of research reported sonography to be an and for detecting and describing endometriosis in the (Figure et suggested that of DIE because may irregular and are no studies that ultrasound in the detection or of in a recent was found to be with are on the of in the diagnosis of DIE on (Figure TVS is the first-line in the of women with underlying The for ultrasound to endometriosis and DIE and is well of forms of DIE as well as using TVS is in a surgical with gynecological ultrasound is to assess the to et found that in and have performed at prior TVS have performed in of the also found that interpretation of the at the was that at the have performed in of in performing the and detecting after approximately and and diagnostic accuracy with regard to interpretation of the TVS to has been found to be with from substantial to for in gynecological In the same the for all was for interpretation of the in the with the to detection of experienced have performed in of in the detection of rectal DIE using TVS after approximately the of DIE affecting the TVS in the of is a accurate and for diagnosis of In this consensus have described a to examining the pelvis in women with suspected endometriosis, and defined terms and measurements to describe the appearance of endometriosis on This consensus opinion the opinion of clinicians, gynecological sonologists, advanced laparoscopic surgeons and radiologists with an in diagnosis and management of endometriosis. Currently, it is difficult to compare results between published because authors use different terms when describing the same structures and locations. We hope that the terms and definitions suggested herein will be adopted in centers around the world. This would result in consistent use of nomenclature when describing the ultrasound location and extent of endometriosis. We believe that the standardization of terminology should allow meaningful comparisons between future studies in women with an ultrasound diagnosis of endometriosis and should facilitate multicenter Figure Transvaginal sonographic a endometrioma with and ground glass echogenicity of and an atypical endometrioma within the with ground glass echogenicity of Figure two endometriomas are fixed to other by adhesions in the pouch of Figure ultrasound of endometrioma in Figure drawings deep infiltrating endometriosis of of of bladder. 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(No abstract on file for this paper.)

BACKGROUND: This study aimed to explore women's experiences of the impact of endometriosis and whether there are differences across three age groups. METHODS: A qualitative descriptive design was conducted using semi-structured focus group discussions with 35 Australian women with endometriosis, in three age groups. All tape-recorded discussions were transcribed verbatim and read line by line to extract meaningful codes and categories using NVivo 9 software through a thematic analysis approach. Categories were then clustered into meaningful themes. RESULTS: Participants' ages ranged from 17 to 53 years and had a history of 2 to 40 years living with endometriosis, with an average delay time to diagnosis of 8.1 years. Two main themes emerged: (1) experiences of living with endometriosis, and (2) impact of endometriosis on women's lives, with 14 discrete categories. The results showed similarities and differences of the impact between the three age groups. The most highlighted impacts were on marital/sexual relationships, social life, and on physical and psychological aspects in all three age groups, but with different orders of priority. Education was the second most highlighted for the 16-24 years, life opportunities and employment for the 25-34 years; and financial impact for those 35 years and above. CONCLUSIONS: Our findings show that endometriosis impacts negatively on different aspects of women's lives. A better understanding of these findings could help to decrease the negative impact of endometriosis by guiding service delivery and future research to meet more effectively the needs of women and teenagers with this condition.

A healthy 25-year-old woman presents with worsening dysmenorrhea, new-onset left lower quadrant pain, and dyspareunia. She has regular menstrual cycles, and her last menstrual period was 3 weeks before presentation. How should this patient be evaluated and treated?

[For a first-person account of endometriosis, see www.cmaj.ca/lookup/doi/10.1503/cmaj.230215][1] KEY POINTS Endometriosis is a chronic condition defined by the presence of endometrial-like tissue outside of the uterus, which can lead to estrogen-driven inflammation. The extent of disease can be

(No abstract on file for this paper.)

BACKGROUND: Endometriosis, defined as the presence of ectopic endometrial stroma and epithelium, affects approximately 10% of reproductive-age women and can cause pelvic pain and infertility. Endometriotic lesions are considered to be benign inflammatory lesions but have cancerlike features such as local invasion and resistance to apoptosis. METHODS: We analyzed deeply infiltrating endometriotic lesions from 27 patients by means of exomewide sequencing (24 patients) or cancer-driver targeted sequencing (3 patients). Mutations were validated with the use of digital genomic methods in microdissected epithelium and stroma. Epithelial and stromal components of lesions from an additional 12 patients were analyzed by means of a droplet digital polymerase-chain-reaction (PCR) assay for recurrent activating KRAS mutations. RESULTS: Exome sequencing revealed somatic mutations in 19 of 24 patients (79%). Five patients harbored known cancer driver mutations in ARID1A, PIK3CA, KRAS, or PPP2R1A, which were validated by Safe-Sequencing System or immunohistochemical analysis. The likelihood of driver genes being affected at this rate in the absence of selection was estimated at P=0.001 (binomial test). Targeted sequencing and a droplet digital PCR assay identified KRAS mutations in 2 of 3 patients and 3 of 12 patients, respectively, with mutations in the epithelium but not the stroma. One patient harbored two different KRAS mutations, c.35G→T and c.35G→C, and another carried identical KRAS c.35G→A mutations in three distinct lesions. CONCLUSIONS: We found that lesions in deep infiltrating endometriosis, which are associated with virtually no risk of malignant transformation, harbor somatic cancer driver mutations. Ten of 39 deep infiltrating lesions (26%) carried driver mutations; all the tested somatic mutations appeared to be confined to the epithelial compartment of endometriotic lesions.

IMPORTANCE: Endometriosis has been associated with an increased risk of ovarian cancer; however, the associations between endometriosis subtypes and ovarian cancer histotypes have not been well-described. OBJECTIVE: To evaluate the associations of endometriosis subtypes with incidence of ovarian cancer, both overall and by histotype. DESIGN, SETTING, AND PARTICIPANTS: Population-based cohort study using data from the Utah Population Database. The cohort was assembled by matching 78 893 women with endometriosis in a 1:5 ratio to women without endometriosis. EXPOSURES: Endometriosis cases were identified via electronic health records and categorized as superficial endometriosis, ovarian endometriomas, deep infiltrating endometriosis, or other. MAIN OUTCOMES AND MEASURES: Estimated adjusted hazard ratios (aHRs), adjusted risk differences (aRDs) per 10 000 women, and 95% CIs for overall ovarian cancer, type I ovarian cancer, and type II ovarian cancer comparing women with each type of endometriosis with women without endometriosis. Models accounted for sociodemographic factors, reproductive history, and past gynecologic operations. RESULTS: In this Utah-based cohort, the mean (SD) age at first endometriosis diagnosis was 36 (10) years. There were 597 women with ovarian cancer. Ovarian cancer risk was higher among women with endometriosis compared with women without endometriosis (aHR, 4.20 [95% CI, 3.59-4.91]; aRD, 9.90 [95% CI, 7.22-12.57]), and risk of type I ovarian cancer was especially high (aHR, 7.48 [95% CI, 5.80-9.65]; aRD, 7.53 [95% CI, 5.46-9.61]). Ovarian cancer risk was highest in women with deep infiltrating endometriosis and/or ovarian endometriomas for all ovarian cancers (aHR, 9.66 [95% CI, 7.77-12.00]; aRD, 26.71 [95% CI, 20.01-33.41]), type I ovarian cancer (aHR, 18.96 [95% CI, 13.78-26.08]; aRD, 19.57 [95% CI, 13.80-25.35]), and type II ovarian cancer (aHR, 3.72 [95% CI, 2.31-5.98]; aRD, 2.42 [95% CI, -0.01 to 4.85]). CONCLUSIONS AND RELEVANCE: Ovarian cancer risk was markedly increased among women with ovarian endometriomas and/or deep infiltrating endometriosis. This population may benefit from counseling regarding ovarian cancer risk and prevention and could be an important population for targeted screening and prevention studies.

Adenomyosis, characterized by the presence of endometrial glands and stroma within the myometrium, can have a substantial impact on the quality of women's lives. Despite this, the epidemiologic research on this condition lags considerably behind that of other noncancerous reproductive health conditions. The lack of progress and knowledge is due in part to the challenges in designing valid epidemiologic studies, since the diagnosis of adenomyosis historically has been limited to the examination of uterine specimens from hysterectomy. This review describes the available data on the frequency of this condition and the epidemiologic investigation thus far into the risk factors for disease-highlighting the methodologic and inference challenges primarily around study sample selection. We conclude with providing recommendations for approaches to future epidemiologic study that capitalize on the advancements in imaging technology to detect adenomyosis and provide a fuller picture of the occurrence and risk factors for disease.

Endometriosis (EMs) is a chronic inflammatory disorder characterized by dysregulated innate immunity, particularly impaired cytotoxic function of natural killer (NK) cells. As pivotal effectors of the innate immune response, NK cells fail to eliminate ectopic endometrial lesions due to aberrant receptor-ligand interactions, elevated levels of immunosuppressive cytokines (TGF-β, IL-6, and IL-10), and dysfunction of adhesion molecules. This compromised immune surveillance facilitates the survival and implantation of ectopic lesions, contributing to the hallmark symptoms of pain and infertility. Recent immunotherapeutic strategies, including NK cell checkpoint blockade (anti-NKG2A, anti-PD-1), IL-2-based activation, and adoptive NK cell transfer-seek to restore NK cell cytotoxicity and reestablish immune homeostasis. This review summarizes current advances in understanding NK cell dysfunction in EMs, emphasizing its central role in immune evasion and the therapeutic promise of targeting innate immune pathways.

(No abstract on file for this paper.)

Despite the clinically recognized association between endometriosis and infertility, the mechanisms implicated in endometriosis-associated infertility are not fully understood. Endometriosis is a multifactorial and systemic disease that has pleiotropic direct and indirect effects on reproduction. A complex interaction between endometriosis subtype, pain, inflammation, altered pelvic anatomy, adhesions, disrupted ovarian reserve/function, and compromised endometrial receptivity as well as systemic effects of the disease define endometriosis-associated infertility. The population of infertile women with endometriosis is heterogeneous, and diverse patients' phenotypes can be observed in the clinical setting, thus making difficult to establish a precise diagnosis and a single mechanism of endometriosis related infertility. Moreover, clinical management of infertility associated with endometriosis can be challenging due to this heterogeneity. Innovative non-invasive diagnostic tools are on the horizon that may allow us to target the specific dysfunctional alteration in the reproduction process. Currently the treatment should be individualized according to the clinical situation and to the suspected level of impairment. Here we review the etiology of endometriosis related infertility as well as current treatment options, including the roles of surgery and assisted reproductive technologies.

BACKGROUND: This study aimed to calculate costs and health-related quality of life of women with endometriosis-associated symptoms treated in referral centres. METHODS: A prospective, multi-centre, questionnaire-based survey measured costs and quality of life in ambulatory care and in 12 tertiary care centres in 10 countries. The study enrolled women with a diagnosis of endometriosis and with at least one centre-specific contact related to endometriosis-associated symptoms in 2008. The main outcome measures were health care costs, costs of productivity loss, total costs and quality-adjusted life years. Predictors of costs were identified using regression analysis. RESULTS: Data analysis of 909 women demonstrated that the average annual total cost per woman was €9579 (95% confidence interval €8559-€10 599). Costs of productivity loss of €6298 per woman were double the health care costs of €3113 per woman. Health care costs were mainly due to surgery (29%), monitoring tests (19%) and hospitalization (18%) and physician visits (16%). Endometriosis-associated symptoms generated 0.809 quality-adjusted life years per woman. Decreased quality of life was the most important predictor of direct health care and total costs. Costs were greater with increasing severity of endometriosis, presence of pelvic pain, presence of infertility and a higher number of years since diagnosis. CONCLUSIONS: Our study invited women to report resource use based on endometriosis-associated symptoms only, rather than drawing on a control population of women without endometriosis. Our study showed that the economic burden associated with endometriosis treated in referral centres is high and is similar to other chronic diseases (diabetes, Crohn's disease, rheumatoid arthritis). It arises predominantly from productivity loss, and is predicted by decreased quality of life.

BACKGROUND: Fibrosis is an important pathological feature of endometriotic lesions of all subtypes. Fibrosis is present in and around endometriotic lesions, and a central role in its development is played by myofibroblasts, which are cells derived mainly after epithelial-to-mesenchymal transition (EMT) and fibroblast-to-myofibroblast transdifferentiation (FMT). Transforming growth factor-β (TGF-β) has a key role in this myofibroblastic differentiation. Myofibroblasts deposit extracellular matrix (ECM) and have contracting abilities, leading to a stiff micro-environment. These aspects are hypothesized to be involved in the origin of endometriosis-associated pain. Additionally, similarities between endometriosis-related fibrosis and other fibrotic diseases, such as systemic sclerosis or lung fibrosis, indicate that targeting fibrosis could be a potential therapeutic strategy for non-hormonal therapy for endometriosis. OBJECTIVE AND RATIONALE: This review aims to summarize the current knowledge and to highlight the knowledge gaps about the role of fibrosis in endometriosis. A comprehensive literature overview about the role of fibrosis in endometriosis can improve the efficiency of fibrosis-oriented research in endometriosis. SEARCH METHODS: A systematic literature search was performed in three biomedical databases using search terms for 'endometriosis', 'fibrosis', 'myofibroblasts', 'collagen', and 'α-smooth muscle actin'. Original studies were included if they reported about fibrosis and endometriosis. Both preclinical in vitro and animal studies, as well as research concerning human subjects were included. OUTCOMES: Our search yielded 3441 results, of which 142 studies were included in this review. Most studies scored a high to moderate risk of bias according to the bias assessment tools. The studies were divided in three categories: human observational studies, experimental studies with human-derived material, and animal studies. The observational studies showed details about the histologic appearance of fibrosis in endometriosis and the co-occurrence of nerves and immune cells in lesions. The in vitro studies identified several pro-fibrotic pathways in relation to endometriosis. The animal studies mainly assessed the effect of potential therapeutic strategies to halt or regress fibrosis, for example targeting platelets or mast cells. WIDER IMPLICATIONS: This review shows the central role of fibrosis and its main cellular driver, the myofibroblast, in endometriosis. Platelets and TGF-β have a pivotal role in pro-fibrotic signaling. The presence of nerves and neuropeptides is closely associated with fibrosis in endometriotic lesions, and is likely a cause of endometriosis-associated pain. The process of fibrotic development after EMT and FMT shares characteristics with other fibrotic diseases, so exploring similarities in endometriosis with known processes in diseases like systemic sclerosis, idiopathic pulmonary fibrosis or liver cirrhosis is relevant and a promising direction to explore new treatment strategies. The close relationship with nerves appears rather unique for endometriosis-related fibrosis and is not observed in other fibrotic diseases. REGISTRATION NUMBER: N/A.

(No abstract on file for this paper.)

BACKGROUND: Adenomyosis, characterized by the presence of islands of endometrial tissue surrounded by hypertrophic smooth muscle cells within the myometrium, is one of the most challenging uterine disorders in terms of diagnosis and management. Adenomyosis presents with pelvic pain, excessive uterine bleeding, anemia and infertility. The relative contributions of abnormal endometrial tissue and myometrial smooth muscle cells to the development and growth of adenomyosis are not well understood. Moreover, there is continuing debate on the origins of adenomyosis; two competing theories describe the invagination of basal endometrium into the myometrium or the metaplastic differentiation of remnant endometrial stem/progenitor cells within the myometrium. OBJECTIVE AND RATIONALE: A recent series of next-generation sequencing (NGS) studies have provided the best scientific evidence thus far regarding the cellular origins of adenomyosis and the contributions of new signaling pathways to its pathogenesis, survival, and growth. These seminal studies on endometrium, adenomyosis and endometriosis demonstrate or support the following key points. (i) Mutations of KRAS map to both intracavitary endometrial tissue and proximally located adenomyotic samples, supporting the invagination theory of pathogenesis. Driver mutations found in smooth muscle cells of uterine fibroids are absent in adenomyosis. (ii) KRAS and other less frequent mutations are limited to endometrial-type epithelial cells. They are also observed in endometriosis, indicating that the disease process in adenomyosis is similar to that in endometriosis and distinct from that of uterine fibroids. (iii) Activating mutations of KRAS stimulate specific pathways to increase cell survival and proliferation and are associated with progesterone resistance in adenomyosis. Together, these findings suggest that distinct cell populations in eutopic endometrial tissue play key roles in the etiology of adenomyosis. Dependence on ovarian steroids and ovulatory cycles for disease severity is a unique feature of adenomyosis. In this context, common patterns of aberrant gene expression have been reported both in adenomyosis and endometriosis. These include pathways that favor increased estrogen biosynthesis, decreased estradiol metabolism, a unique estrogen receptor beta (ESR2)-driven inflammatory process, and progesterone resistance due to decreased progesterone receptor expression. Since adenomyosis exhibits a uniquely estrogen-driven inflammatory process and progesterone resistance, we discuss the interactions between these molecular characteristics and signaling pathways induced by the newly discovered KRAS mutations. SEARCH METHODS: We conducted a comprehensive search using PubMed for human and animal studies published until 2020 in the following areas: adenomyosis, endometriosis, endometrium, NGS, whole-exome sequencing, whole-genome sequencing, RNA sequencing, targeted deep sequencing, epigenetics, driver mutation, KRAS, progesterone resistance, estrogen action and steroid production. OUTCOMES: Targeted deep sequencing analyses of epithelial cells in adenomyosis and adjacent basalis endometrial glands demonstrated recurring KRAS mutations in both cell types. This finding suggests that adenomyosis originates from basalis endometrium. Epithelial cells of the endometrium, adjacent adenomyosis and co-occurring endometriosis also share identical KRAS mutations. These findings suggest both adenomyosis and endometriosis are oligoclonal tissues that arise from endometrial cell populations carrying a specific driver mutation that most commonly affects the KRAS gene. WIDER IMPLICATIONS: Adenomyosis usually follows an event such as pregnancy that has disrupted the integrity of the endometrial-myometrial junction followed by repetitious menstrual episodes that increase the likelihood of the entrapment of the basalis endometrium within the myometrium. Glandular epithelial cells carrying KRAS mutations and located within the deep crypts of basalis endometrium may become entrapped and invade myometrial tissue to give rise to adenomyosis. Evidence suggests that KRAS mutations may be responsible, in part, for previously observed phenomena such as prolonged cell survival and progesterone resistance in adenomyosis.

(No abstract on file for this paper.)

Endometriosis-associated pain and the mechanisms responsible for its initiation and persistence are complex and difficult to treat. Endometriosis-associated pain is experienced as dysmenorrhea, cyclical pain related to organ function including dysuria, dyschezia and dyspareunia, and persistent pelvic pain. Pain symptomatology correlates poorly with the extent of macroscopic disease. In addition to the local effects of disease, endometriosis-associated pain develops as a product of peripheral sensitization, central sensitization and cross sensitization. Endometriosis-associated pain is further contributed to by comorbid pain conditions, such as bladder pain syndrome, irritable bowel syndrome, abdomino-pelvic myalgia and vulvodynia. This article will review endometriosis-associated pain, its mechanisms, and its comorbid pain syndromes with a view to aiding the clinician in navigating the literature and terminology of pain and pain syndromes. Limitations of our current understanding of endometriosis-associated pain will be acknowledged. Where possible, commonalities in pain mechanisms between endometriosis-associated pain and comorbid pain syndromes will be highlighted.

(No abstract on file for this paper.)

Endometriosis is a common and challenging condition of reproductive-aged women that carries a high individual and societal cost. The many molecular dissimilarities between endometriosis lesions and eutopic endometrium create difficulties in the development of new drug therapies and treatments. Surgery remains the gold standard for definitive diagnosis, but it must be weighed against the risks of surgical morbidity and potential decreases in ovarian reserve, especially in the case of endometriomas. Safe and effective surgical techniques are discussed within this article for various presentations of endometriosis. Medical therapy is suppressive rather than curative, and regimens that are long-term and affordable with minimal side effects are recommended. Recurrences are common and often rapid when medical therapy is discontinued. Endometriosis in the setting of infertility is reviewed and appropriate management is discussed, including when and whether surgery is warranted in this at-risk population. In patients with chronic pain, central sensitization and myofascial pain are integral components of a multidisciplinary approach. Endometriosis is associated with an increased risk of epithelial ovarian cancer; however, the risk is low and currently no preventive screening is recommended. Hormone therapy for symptomatic women with postsurgical menopause should not be delayed as a result of concerns for malignancy or recurrence of endometriosis.

BACKGROUND: Although surgery for endometriosis can improve pain and fertility, the risk of disease recurrence is high. There is little consensus regarding the benefit of medical therapy in preventing recurrence of endometriosis following surgery. OBJECTIVE AND RATIONALE: We performed a review of prospective observational studies and randomised controlled trials (RCTs) to evaluate the risk of endometriosis recurrence in patients undergoing post-operative hormonal suppression, compared to placebo/expectant management. SEARCH METHODS: The following databases were searched from inception to March 2020 for RCTs and prospective observational cohort studies: MEDLINE, Embase, Cochrane CENTRAL and Web of Science. We included English language full-text articles of pre-menopausal women undergoing conservative surgery (conserving at least one ovary) and initiating hormonal suppression within 6 weeks post-operatively with either combined hormonal contraceptives (CHC), progestins, androgens, levonorgesterel-releasing intra-uterine system (LNG-IUS) or GnRH agonist or antagonist. We excluded from the final analysis studies with <12 months of follow-up, interventions of diagnostic laparoscopy, experimental/non-hormonal treatments or combined hormonal therapy. Risk of bias was assessed using the Cochrane Risk of Bias Tool for RCTs and the Newcastle-Ottawa Scale (NOS) for observational studies. OUTCOMES: We included 17 studies (13 RCTs and 4 cohort studies), with 2137 patients (1189 receiving post-operative suppression and 948 controls), which evaluated various agents: CHC (6 studies, n = 869), progestin (3 studies, n = 183), LNG-IUS (2 studies, n = 94) and GnRH agonist (9 studies, n = 1237). The primary outcome was post-operative endometriosis recurrence, determined by imaging or recurrence of symptoms, at least 12 months post-operatively. The secondary outcome was change in endometriosis-related pain. Mean follow up of included studies ranged from 12 to 36 months, and outcomes were assessed at a median of 18 months. There was a significantly decreased risk of endometriosis recurrence in patients receiving post-operative hormonal suppression compared to expectant management/placebo (relative risk (RR) 0.41, 95% CI: 0.26 to 0.65), 14 studies, 1766 patients, I2 = 68%, random effects model). Subgroup analysis on patients treated with CHC and LNG-IUS as well as sensitivity analyses limited to RCTs and high-quality studies showed a consistent decreased risk of endometriosis recurrence. Additionally, the patients receiving post-operative hormonal suppression had significantly lower pain scores compared to controls (SMD -0.49, 95% CI: -0.91 to -0.07, 7 studies, 652 patients, I2 = 68%). WIDER IMPLICATIONS: Hormonal suppression should be considered for patients not seeking pregnancy immediately after endometriosis surgery in order to reduce disease recurrence and pain. Various hormonal agents have been shown to be effective, and the exact treatment choice should be individualised according to each woman's needs.

(No abstract on file for this paper.)

The MUSA (Morphological Uterus Sonographic Assessment) statement is a consensus statement on terms, definitions and measurements that may be used to describe and report the sonographic features of the myometrium using gray-scale sonography, color/power Doppler and three-dimensional ultrasound imaging. The terms and definitions described may form the basis for prospective studies to predict the risk of different myometrial pathologies, based on their ultrasound appearance, and thus should be relevant for the clinician in daily practice and for clinical research. The sonographic features and use of terminology for describing the two most common myometrial lesions (fibroids and adenomyosis) and uterine smooth muscle tumors are presented.

BACKGROUND: Adenomyosis is a benign uterine disorder where endometrial glands and stroma are pathologically demonstrated within the uterine myometrium. The pathogenesis involves sex steroid hormone abnormalities, inflammation, fibrosis and neuroangiogenesis, even though the proposed mechanisms are not fully understood. For many years, adenomyosis has been considered a histopathological diagnosis made after hysterectomy, classically performed in perimenopausal women with abnormal uterine bleeding (AUB) or pelvic pain. Until recently, adenomyosis was a clinically neglected condition. Nowadays, adenomyosis may also be diagnosed by non-invasive techniques, because of imaging advancements. Thus, a new epidemiological scenario has developed with an increasing number of women of reproductive age with ultrasound (US) or magnetic resonance imaging (MRI) diagnosis of adenomyosis. This condition is associated with a wide variety of symptoms (pelvic pain, AUB and/or infertility), but it is also recognised that some women are asymptomatic. Furthermore, adenomyosis often coexists with other gynecological comorbidities, such as endometriosis and uterine fibroids, and the diagnostic criteria are still not universally agreed. Therefore, the diagnostic process for adenomyosis is challenging. OBJECTIVE AND RATIONALE: We present a comprehensive review on the diagnostic criteria of adenomyosis, including clinical signs and symptoms, ultrasound and MRI features and histopathological aspects of adenomyotic lesions. We also briefly summarise the relevant theories on adenomyosis pathogenesis, in order to provide the pathophysiological background to understand the different phenotypes and clinical presentation. The review highlights the controversies of multiple existing criteria, summarising all of the available evidences on adenomyosis diagnosis. The review aims also to underline the future perspective for diagnosis, stressing the importance of an integrated clinical and imaging approach, in order to identify this gynecological disease, so often underdiagnosed. SEARCH METHODS: PubMed and Google Scholar were searched for all original and review articles related to diagnosis of adenomyosis published in English until October 2018. OUTCOMES: The challenge in diagnosing adenomyosis starts with the controversies in the available pathogenic theories. The difficulties in understanding the way the disease arises and progresses have an impact also on the specific diagnostic criteria to use for a correct identification. Currently, the diagnosis of adenomyosis may be performed by non-invasive methods and the clinical signs and symptoms, despite their heterogeneity and poor specificity, may guide the clinician for a suspicion of the disease. Imaging techniques, including 2D and 3D US as well as MRI, allow the proper identification of the different phenotypes of adenomyosis (diffuse and/or focal). From a histological point of view, if the diagnosis of diffuse adenomyosis is straightforward, in more limited disease, the diagnosis has poor inter-observer reproducibility, leading to extreme variations in the prevalence of disease. Therefore, an integrated non-invasive diagnostic approach, considering risk factors profile, clinical symptoms, clinical examination and imaging, is proposed to adequately identify and characterise adenomyosis. WIDER IMPLICATIONS: The development of the diagnostic tools allows the physicians to make an accurate diagnosis of adenomyosis by means of non-invasive techniques, representing a major breakthrough, in the light of the clinical consequences of this disease. Furthermore, this technological improvement will open a new epidemiological scenario, identifying different groups of women, with a dissimilar clinical and/or imaging phenotypes of adenomyosis, and this should be object of future research.

BACKGROUND: Endometriosis is a disease known to be detrimental to fertility. Women with endometriosis, and the presence of endometrioma, may require artificial reproductive techniques (ART) to achieve a pregnancy. The specific impact of endometrioma alone and the impact of surgical intervention for endometrioma on the reproductive outcome of women undergoing IVF/ICSI are areas that require further clarification. The objectives of this review were as follows: (i) to determine the impact of endometrioma on IVF/ICSI outcomes, (ii) to determine the impact of surgery for endometrioma on IVF/ICSI outcome and (iii) to determine the effect of different surgical techniques on IVF/ICSI outcomes. METHODS: We performed a systematic review and meta-analysis examining subfertile women who have endometrioma and are undergoing IVF/ICSI, and who have or have not had any surgical management for endometrioma before IVF/ICSI. The primary outcome was live birth rate (LBR). Our secondary outcomes were clinical pregnancy rate (CPR), mean number of oocyte retrieved (MNOR), miscarriage rate (MR), fertilization rate, implantation rate, antral follicle count (AFC), total stimulating hormone dose, and any rates of adverse effects such as cancellation and associated complications during the IVF/ICSI treatment. RESULTS: We included 33 studies for the meta-analysis. The majority of the studies were retrospective (30/33), and three were RCTs. Compared with women with no endometrioma undergoing IVF/ICSI, women with endometrioma had a similar LBR (odds ratio [OR] 0.98; 95% CI [0.71, 1.36], 5 studies, 928 women, I(2) = 0%) and a similar CPR (OR 1.17; 95% CI [0.87, 1.58], 5 studies, 928 women, I(2) = 0%), a lower mean number of oocytes retrieved (SMD -0.23; 95% CI [-0.37, -0.10], 5 studies, 941 cycles, I(2) = 37%) and a higher cycle cancellation rate compared with those without the disease (OR 2.83; 95% CI [1.32, 6.06], 3 studies, 491 women, I(2) = 0%). Compared with women with no surgical treatment, women who had their endometrioma surgically treated before IVF/ICSI had a similar LBR (OR 0.90; 95% CI [0.63, 1.28], 5 studies, 655 women, I(2) = 32%), a similar CPR (OR 0.97; 95% CI [0.78, 1.20], 11 studies, 1512 women, I(2) = 0%) and a similar mean number of oocytes retrieved (SMD -0.17; 95% CI [-0.38, 0.05], 9 studies, 810 cycles, I(2) = 63%). CONCLUSIONS: Women with endometrioma undergoing IVF/ICSI had similar reproductive outcomes compared with those without the disease, although their cycle cancellation rate was significantly higher. Surgical treatment of endometrioma did not alter the outcome of IVF/ICSI treatment compared with those who did not receive surgical intervention. Considering that the reduced ovarian reserve may be attributed to the presence of endometrioma per se, and the potential detrimental impact from surgical intervention, individualization of care for women with endometrioma prior to IVF/ICSI may help optimize their IVF/ICSI results.

Endometriosis is a common cause of pelvic pain and affects up to 10% of women of reproductive age. Aberrant progesterone signaling in the endometrium plays a significant role in impaired decidualization and establishment of ectopic endometrial implants. Eutopic endometrial cells from women with endometriosis fail to downregulate genes needed for decidualization, such as those involved in cell cycle regulation, leading to unbridled proliferation. Several causes of progesterone resistance in the endometrium have been postulated, including congenital "preconditioning", whereby the in utero environment renders infants susceptible to neonatal uterine bleeding and endometriosis. Progesterone action is crucial to decreasing inflammation in the endometrium, and deviant progesterone signaling results in a proinflammatory phenotype. Conversely, chronic inflammation can induce a progesterone-resistant state. Repetitive retrograde endometrial shedding begets chronic peritoneal inflammation, which further exacerbates progesterone resistance. Genetic causes of progesterone resistance include progesterone receptor gene polymorphisms, altered microRNA expression, and epigenetic modifications to progesterone receptors and their targets. Environmental toxins such as dioxin play a possible role in the genesis of endometriosis by permitting an inflammatory milieu. A consequence of impaired progesterone action is that hormonal therapy is rendered ineffective for a subset of women with endometriosis. Synthetic progestins, such as dienogest, may overcome this phenomenon by increasing progesterone receptor expression and decreasing proinflammatory cytokines. Other modalities include high dose depot formulations of progestins, medicated intrauterine devices and the likely advent of oral GnRH antagonists. Unearthing root causes of progesterone inaction in endometriosis will aid in the development of novel therapeutics geared toward prevention and treatment.

Endometriosis is a chronic disease that affects about 10% of women of reproductive age. It can contribute to pelvic pain, infertility or other conditions such as asthma, cardiovascular disease, breast or ovarian cancer. Research has shown that one of the conditions for the development of endometrial lesions is the dysfunction of the immune system. It appears that immune cells, such as neutrophils, macrophages, NK cells and dendritic cells, may play a specific role in the angiogenesis, growth and invasion of endometriosis cells. Immune cells secrete cytokines and defensins that also affect the endometriosis environment. This review discusses the various components of the immune system that are involved in the formation of endometrial lesions in women.

STUDY QUESTION: To what extent do the management of endometriosis and the symptoms that remain after treatment affect the quality of life in women with the disease? SUMMARY ANSWER: Many women with endometriosis had impaired quality of life and continued to suffer from endometriosis-associated symptoms even though their endometriosis has been managed in tertiary care centres. WHAT IS KNOWN ALREADY: The existing literature indicates that quality of life and work productivity is reduced in women with endometriosis. However, most studies have small sample sizes, are treatment related or examine newly diagnosed patients only. STUDY DESIGN, SIZE, DURATION: A cross-sectional questionnaire-based survey among 931 women with endometriosis treated in 12 tertiary care centres in 10 countries. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women diagnosed with endometriosis who had at least one contact related to endometriosis-associated symptoms during 2008 with a participating centre were enrolled into the study. The study investigated the effect of endometriosis on education, work and social wellbeing, endometriosis-associated symptoms and health-related quality of life, by using questions obtained from the World Endometriosis Research Foundation (WERF) GSWH instrument (designed and validated for the WERF Global Study on Women's Health) and the Short Form 36 version 2 (SF-36v2). MAIN RESULTS AND THE ROLE OF CHANCE: Of 3216 women invited to participate in the study, 1450 (45%) provided informed consent and out of these, 931 (931/3216 = 29%) returned the questionnaires. Endometriosis had affected work in 51% of the women and affected relationships in 50% of the women at some time during their life. Dysmenorrhoea was reported by 59%, dyspareunia by 56% and chronic pelvic pain by 60% of women. Quality of life was decreased in all eight dimensions of the SF-36v2 compared with norm-based scores from a general US population (all P < 0.01). Multivariate regression analysis showed that number of co-morbidities, chronic pain and dyspareunia had an independent negative effect on both the physical and mental component of the SF-36v2. LIMITATIONS, REASONS FOR CAUTION: The fact that women were enrolled in tertiary care centres could lead to a possible over-representation of women with moderate-to-severe endometriosis, because the participating centres typically treat more complex and referred cases of endometriosis. The response rate was relatively low. Since there was no Institute Review Board approval to do a non-responder investigation on basic characteristics, some uncertainty remains regarding the representativeness of the investigated population. WIDER IMPLICATIONS OF THE FINDINGS: This international multicentre survey represents a large group of women with endometriosis, in all phases of the disease, which increases the generalizability of the data. Women still suffer from frequent symptoms, despite tertiary care management, in particular chronic pain and dyspareunia. As a result their quality of life is significantly decreased. A patient-centred approach with extensive collaboration across disciplines, such as pain specialists, psychologists, sexologists and social workers, may be a valuable strategy to improve the long-term care of women with endometriosis. STUDY FUNDING/COMPETING INTEREST(S): The WERF EndoCost study is funded by the World Endometriosis Research Foundation (WERF) through grants received from Bayer Schering Pharma AG, Takeda Italia Farmaceutici SpA, Pfizer Ltd and the European Society of Human Reproduction and Embryology. The sponsors did not have a role in the design and conduct of the study; collection, management, analysis and interpretation of the data; and preparation, review or approval of the manuscript. L.H. is the chief executive and T.D. was a board member of WERF at the time of funding. T.D. holds the Merck-Serono Chair in Reproductive Medicine and Surgery, and the Ferring Chair in Reproductive Medicine at the Katholieke Universiteit Leuven in Belgium and has served as consultant/research collaborator for Merck-Serono, Schering-Plough, Astellas and Arresto.

The etiopathogenesis of endometriosis is a multifactorial process resulting in a heterogeneous disease. Considering that endometriosis etiology and pathogenesis are still far from being fully elucidated, the current review aims to offer a comprehensive summary of the available evidence. We performed a narrative review synthesizing the findings of the English literature retrieved from computerized databases from inception to June 2019, using the Medical Subject Headings (MeSH) unique ID term "Endometriosis" (ID:D004715) with "Etiology" (ID:Q000209), "Immunology" (ID:Q000276), "Genetics" (ID:D005823) and "Epigenesis, Genetic" (ID:D044127). Endometriosis may origin from Müllerian or non-Müllerian stem cells including those from the endometrial basal layer, Müllerian remnants, bone marrow, or the peritoneum. The innate ability of endometrial stem cells to regenerate cyclically seems to play a key role, as well as the dysregulated hormonal pathways. The presence of such cells in the peritoneal cavity and what leads to the development of endometriosis is a complex process with a large number of interconnected factors, potentially both inherited and acquired. Genetic predisposition is complex and related to the combined action of several genes with limited influence. The epigenetic mechanisms control many of the processes involved in the immunologic, immunohistochemical, histological, and biological aberrations that characterize the eutopic and ectopic endometrium in affected patients. However, what triggers such alterations is not clear and may be both genetically and epigenetically inherited, or it may be acquired by the particular combination of several elements such as the persistent peritoneal menstrual reflux as well as exogenous factors. The heterogeneity of endometriosis and the different contexts in which it develops suggest that a single etiopathogenetic model is not sufficient to explain its complex pathobiology.

PURPOSE: The purpose of this consensus article was to develop guidelines by a focused panel of experts to elaborate a lexicon of image interpretation, and a standardized region-based reporting of deep infiltrating endometriosis (DIE) with magnetic resonance imaging (MRI). MATERIALS AND METHODS: Evidence-based data and expert opinion were combined using the RAND-UCLA Appropriateness Method to attain consensus guidelines. Experts scoring of pelvic compartment delineation and reporting template were collected; responses were analyzed and classified as "RECOMMENDED" versus "NOT RECOMMENDED" (when ≥ 80% consensus among experts) or uncertain (when < 80% consensus among experts). RESULTS: Consensus regarding pelvic compartment delineation and DIE reporting was attained using the RAND-UCLA Appropriateness Method. The pelvis was divided in nine compartments and extrapelvic lesions were assigned to an additional (tenth) compartment. A consensus was also reached for each structure attributed to a compartment and each reporting template item among the experts. No consensus was reached for a normal aspect of uterosacral ligament, but a consensus was reached for an unequivocal involvement leading to a positive diagnosis and an equivocal involvement leading to uncertain diagnosis. Tailored MRI lexicon and standardized region-based report were proposed. CONCLUSION: These consensus recommendations should be used as a guide for DIE reporting and staging with MRI. Standardized MRI compartment-based structured reporting is recommended to enable consistent accuracy and help select the best therapeutic approach.

Endometriosis (EM) is one of the most common diseases among women of reproductive age. The etiology and pathogenesis of EM remain unclear and therefore there is a lack of effective treatment measures, which affects physical and mental health, as well as the quality of life of patients with EM. Angiogenesis has become a hotspot for research on the pathogenesis of EM; the role of angiogenesis‑related serological markers and anti‑angiogenic therapy in the diagnosis and treatment of EM is promising for early diagnosis and treatment of EM. Angiogenesis in EM is subject to complex regulation by hormones, immunity and associated cytokines. Therefore, novel targets for angiogenesis therapy are also being discovered and developed. The present review summarized the pathological mechanisms of angiogenesis and the value of relevant markers in pathogenesis and diagnosis of EM, along with the status of research on anti‑angiogenic drugs in the treatment of EM. The role of angiogenesis in EM provides an important reference for treatment and diagnosis, but there is no uniform non‑invasive diagnostic marker and proven strategy for anti‑angiogenesis.

Endometriosis (EM), a chronic condition in endometrial tissue outside the uterus, affects around 10% of reproductive-age women, significantly affecting fertility. Its prevalence remains elusive due to the surgical confirmation needed for diagnosis. Manifesting with a range of symptoms, including dysmenorrhea, dyschezia, dysuria, dyspareunia, fatigue, and gastrointestinal discomfort, EM significantly impairs quality of life due to severe chronic pelvic pain (CPP). Psychological manifestations, notably depression and anxiety, frequently accompany the physical symptoms, with CPP serving as a key mediator. Pain stems from endometrial lesions, involving oxidative stress, neuroinflammation, angiogenesis, and sensitization processes. Microbial dysbiosis appears to be crucial in the inflammatory mechanisms underlying EM and associated CPP, as well as psychological symptoms. In this scenario, dietary interventions and nutritional supplements could help manage EM symptoms by targeting inflammation, oxidative stress, and the microbiome. Our manuscript starts by delving into the complex relationship between EM pain and psychological comorbidities. It subsequently addresses the emerging roles of the microbiome, inflammation, and oxidative stress as common links among these abovementioned conditions. Furthermore, the review explores how dietary and nutritional interventions may influence the composition and function of the microbiome, reduce inflammation and oxidative stress, alleviate pain, and potentially affect EM-associated psychological disorders.

Copyright © 2017 Massachusetts Medical Society. BACKGROUND Endometriosis is a chronic, estrogen-dependent condition that causes dysmenorrhea and pelvic pain. Elagolix, an oral, nonpeptide, gonadotropin-releasing hormone (GnRH) antagonist, produced partial to nearly full estrogen suppression in previous studies. METHODS We performed two similar, double-blind, randomized, 6-month phase 3 trials (Elaris Endometriosis I and II [EM-I and EM-II]) to evaluate the effects of two doses of elagolix-150 mg once daily (lower-dose group) and 200 mg twice daily (higher-dose group)-as compared with placebo in women with surgically diagnosed endometriosis and moderate or severe endometriosis-associated pain. The two primary efficacy end points were the proportion of women who had a clinical response with respect to dysmenorrhea and the proportion who had a clinical response with respect to nonmenstrual pelvic pain at 3 months. Each of these end points was measured as a clinically meaningful reduction in the pain score and a decreased or stable use of rescue analgesic agents, as recorded in a daily electronic diary. RESULTS A total of 872 women underwent randomization in Elaris EM-I and 817 in Elaris EM-II; of these women, 653 (74.9%) and 632 (77.4%), respectively, completed the intervention. At 3 months, a significantly greater proportion of women who received each elagolix dose met the clinical response criteria for the two primary end points than did those who received placebo. In Elaris EM-I, the percentage of women who had a clinical response with respect to dysmenorrhea was 46.4% in the lower-dose elagolix group and 75.8% in the higher-dose elagolix group, as compared with 19.6% in the placebo group; in Elaris EM-II, the corresponding percentages were 43.4% and 72.4%, as compared with 22.7% (P<0.001 for all comparisons). In Elaris EM-I, the percentage of women who had a clinical response with respect to nonmenstrual pelvic pain was 50.4% in the lower-dose elagolix group and 54.5% in the higher-dose elagolix group, as compared with 36.5% in the placebo group (P<0.001 for all comparisons); in Elaris EM-II, the corresponding percentages were 49.8% and 57.8%, as compared with 36.5% (P = 0.003 and P<0.001, respectively). The responses with respect to dysmenorrhea and nonmenstrual pelvic pain were sustained at 6 months. Women who received elagolix had higher rates of hot flushes (mostly mild or moderate), higher levels of serum lipids, and greater decreases from baseline in bone mineral density than did those who received placebo; there were no adverse endometrial findings. CONCLUSIONS Both higher and lower doses of elagolix were effective in improving dysmenorrhea and nonmenstrual pelvic pain during a 6-month period in women with endometriosis-associated pain. The two doses of elagolix were associated with hypoestrogenic adverse effects.

BACKGROUND: Endometriosis is an often chronic, inflammatory gynaecologic condition affecting 190 million women worldwide. Studies have reported an elevated cancer risk among patients with endometriosis. However, prior research has included methodologic issues that impede valid and robust interpretation. OBJECTIVE AND RATIONALE: We conducted a meta-analysis of studies investigating the association between endometriosis and cancer risk and analysed the results by methodologic characteristics. We discuss the implications of cancer screening in patients and management challenges faced by clinicians. SEARCH METHODS: We searched PubMed and Embase databases for eligible studies from inception through 24 October 2019. We included cohort and case-control studies examining the association between endometriosis and cancer risk; cross-sectional studies and case reports were excluded. Publications had to present risk/rate/odds estimates with 95% CI. Random effects meta-analysis was used to estimate summary relative risks (SRR) and CIs. Heterogeneity across studies was assessed by the Q test and I2 statistics, and publication bias using Egger's and Begg's tests. Risk of bias and quality of the included studies were assessed using the risk of bias in non-randomized studies of interventions (ROBINS-I) tool. OUTCOMES: Forty-nine population-based case-control and cohort studies were included. Twenty-six studies were scored as having a 'serious'/'critical' risk of bias, and the remaining 23 'low'/'moderate'. Cancer-specific analyses showed a positive association between endometriosis and ovarian cancer risk (SRR = 1.93, 95% CI = 1.68-2.22; n = 24 studies) that was strongest for clear cell (SRR = 3.44, 95% CI = 2.82-4.42; n = 5 studies) and endometrioid (SRR = 2.33, 95% CI = 1.82-2.98; n = 5 studies) histotypes (Pheterogeneity < 0.0001), although with significant evidence of both heterogeneity across studies and publication bias (Egger's and Begg's P-values < 0.01). A robust association was observed between endometriosis and thyroid cancer (SRR = 1.39, 95% CI =1.24-1.57; n = 5 studies), a very small association with breast cancer (SRR = 1.04, 95% CI =1.00-1.09; n = 20 studies) and no association with colorectal cancer (SRR = 1.00, 95% CI =0.87-1.16; n = 5 studies). The association with endometrial cancer was not statistically significant (SRR = 1.23, 95% CI =0.97-1.57; n = 17 studies) overall and wholly null when restricted to prospective cohort studies (SRR = 0.99, 95% CI =0.72-1.37; n = 5 studies). The association with cutaneous melanoma was also non-significant (SRR = 1.17, 95% CI =0.97-1.41; n = 7 studies) but increased in magnitude and was statistically significant when restricted to studies with low/moderate risk of bias (SRR = 1.71, 95% CI = 1.24-2.36, n = 2 studies). The most robust finding both in terms of statistical significance and magnitude of effect was an inverse association with cervical cancer (SRR = 0.68, 95% CI =0.56-0.82; n = 4 studies); however, this result has a high potential to reflect heightened access to detection of dysplasia for women who reached an endometriosis diagnosis and is thus likely not causal. Several additional cancer types were explored based on <4 studies. WIDER IMPLICATIONS: Endometriosis was associated with a higher risk of ovarian and thyroid, and minimally (only 4% greater risk) with breast cancer, and with a lower risk of cervical cancer. However, this meta-analysis confirms that: a majority of studies had severe/critical risk of bias; there is impactful heterogeneity across studies-and for ovarian cancer, publication bias; and causal inference requires temporality, which in many studies was not considered. We discuss the implications of these potential associations from the perspectives of patients with endometriosis, clinicians involved in their care, and scientists investigating their long-term health risks.