Clinical Manifestations, Diagnosis, and Treatment of Endometriosis

Background: Endometriosis is characteristically defined as the presence of endometrial glands and stroma outside the uterine cavity. Despite an estimated prevalence of 10% in women, the specific etiology, molecular, and clinical aspects of this disease remain poorly understood. Objective: This review further elucidates current theories of the origins of endometriosis and additionally provides a thorough outlook on clinical presentation, diagnosis and treatment modalities utilized presently. Methods: Relevant studies describing the etiology, diagnosis and treatment of endometriosis were comprehensively searched using PubMed, Cochrane Library, Web of Science, and Google Scholar and critically reviewed. Results: Classical theories of origin include retrograde menstruation, coelomic metaplasia, and vascular and lymphatic dissemination, whilst neoclassical theories of endometriosis genesis include the presence of altered immunity and subsistent aberrations in genetic expression in the eutopic endometrium of women afflicted with this condition. Risk factors are manifold, with incessant menstruation playing a substantial role. Other notable risk factors include Asian race and a family history of endometriosis. Clinical presentation is variable, often times poorly correlating with severity of disease, and while newer imaging modalities such as MRI are promising, histopathological confirmation after surgical evaluation remains the gold standard for diagnosis. Optimal treatment is largely dependent upon patient symptomology, and principal therapeutic strategies ought to vary based upon the severity of pain and the presence of other comorbidities including infertility. Predominant pain symptoms may be managed conservatively with NSAIDs or with hormonal modalities including progestins, estroprogestins, gonadotropin releasing hormone (GnRH) analogs and levonorgestrel intrauterine system (LNG-IUS). Aromatase inhibitors and GnRH antagonists may offer a novel approach to management of persistent disease symptoms. Surgical exploration with excision or ablation of endometriosis lesions is another effective approach for patients who are intolerant of or do not desire hormonal intervention. Recently, the management paradigm for infertility- dominant symptoms has been altered, with most experts now recommending avoidance of surgical intervention and initiating timely fertility treatment with ovulation induction or in vitro fertilization. Conclusions: Non-surgical diagnosis of this disease remains fraught with challenges. Treatment modalities are manifold depending on pain-dominant or infertility-dominant symptomatology but are oftentimes poorly efficacious. Ultimately, unearthing the root molecular mechanisms of this complex disease will pave the way for the development of novel preventative and therapeutic measures. Keywords: Endometriosis, dysmenorrhea, estrogen, progestin, GnRH, treatment.