Diffuse Adenomyosis Coexisting with rASRM Stage IV Endometriosis in a Young Woman: Diagnostic Delay and Imaging Discrepancy

A 22-year-old nulligravid woman (P0A0), married for six months and desiring future fertility, was referred to our tertiary referral center with a diagnosis of adenomyosis, bilateral ovarian endometriomas, and left hydrosalpinx. She reported severe dysmenorrhea beginning at 13 years of age, approximately one year after menarche. The pain progressively worsened over time, becoming localized predominantly to the left lower abdomen, beginning one to two days before menstruation and persisting until the first day of menses. The severity of pain substantially interfered with her daily activities. Despite longstanding symptoms, medical evaluation was delayed because both the patient and her family considered severe menstrual pain to be a normal menstrual experience. A family history of severe dysmenorrhea was reported in her mother. The chronology of symptom progression, diagnostic evaluation, surgical management, and postoperative follow-up is summarized in Table 1 . Table 1 Timeline of Clinical Presentation, Diagnostic Evaluation, and Management Time Clinical Events Findings / Management 13 y.o (1 year after menarche) Onset of severe dysmenorrhea Progressive menstrual pain beginning 1–2 days before menstruation and persisting until the first day of menses. Symptoms were initially considered a normal menstrual experience. Adolescence to early adulthood Progressive symptoms Dysmenorrhea gradually worsened and became associated with chronic pelvic pain, dyschezia, dysuria during menstruation, and intermittent intermenstrual spotting. Family history of severe dysmenorrhea in the patient’s mother may have contributed to delayed medical evaluation. 22 y.o Referral to tertiary hospital Evaluated for suspected adenomyosis, bilateral endometriomas, hydrosalpinx, and possible deep infiltrating endometriosis while expressing a desire for future fertility. Preoperative TVUS Initial imaging evaluation Diffuse posterior adenomyosis according to MUSA criteria, bilateral ovarian endometriomas, left hydrosalpinx, posterior compartment lesion suspicious for deep infiltrating endometriosis (DIE), and a negative sliding sign suggestive of pelvic adhesions. Preoperative MRI Pelvic MRI Confirmed diffuse posterior adenomyosis and bilateral adnexal lesions. Operative Laparoscopic surgery Grade II–III pelvic adhesions involving the posterior compartment, bilateral ovarian endometriomas, left hydrosalpinx, posterior compartment DIE, and diffuse posterior adenomyosis. Fertility-preserving laparoscopic adenomyomectomy, bilateral ovarian cystectomy, adhesiolysis, left salpingectomy, and tubal patency testing were performed. The right fallopian tube demonstrated positive spill. Postoperative histopathology Histological confirmation Adenomyosis, bilateral ovarian endometriomas, and chronic inflammatory changes within the fallopian tube without evidence of malignancy. Postoperative follow-up Medical and fertility planning The patient recovered uneventfully and was prescribed dienogest 2 mg once daily while awaiting future fertility treatment. She was counseled regarding assisted reproductive technology, including intrauterine insemination (IUI) or in vitro fertilization (IVF), depending on future fertility evaluation. Timeline of Clinical Presentation, Diagnostic Evaluation, and Management The patient also experienced dyschezia and dysuria during menstruation, intermittent intermenstrual spotting five days before presentation, and recurrent clear, pruritic, malodorous vaginal discharge. Menstrual cycles were regular every 28–30 days, lasting 6–7 days, with relatively heavy menstrual bleeding during the first three days requiring three to four sanitary pads daily. Menarche occurred at 12 years of age. She denied weight loss, anorexia, or other constitutional symptoms. General physical examination was unremarkable. Pelvic examination demonstrated normal vulvar, vaginal, and cervical findings. Bimanual examination revealed no palpable adnexal mass or obvious uterine enlargement. Transvaginal ultrasound was performed by a gynecologist experienced in gynecologic ultrasound. The examination demonstrated a retroflexed uterus measuring 6.96×3.7 × 4.4 cm. A diffuse hyperechoic lesion was identified in the posterior uterine wall, consistent with diffuse adenomyosis. The sonographic features included heterogeneous myometrial echotexture, asymmetrical posterior myometrial thickening, and an indistinct junctional zone, in accordance with the Morphological Uterus Sonographic Assessment (MUSA) criteria. The right ovary contained multiple cystic lesions with ground-glass appearance measuring 2.2×1.6 cm, 1.6×1.09 cm, and 1.33 cm. The left ovary demonstrated a cystic lesion measuring 3.52×3.58 × 2.89 cm with similar features, consistent with bilateral ovarian endometriomas. A hypoechoic nodule measuring 2.44×1.94 cm was identified in the posterior pelvic compartment, suspected to originate from the bowel, suggesting deep infiltrating endometriosis (DIE). In addition, a tubular hypoechoic structure measuring 12.33×3.7 cm with mobile septations was observed, consistent with hydrosalpinx. The sliding sign was negative, indicating reduced organ mobility and suggesting pelvic adhesions ( Figure 1 ). Figure 1 Transvaginal ultrasound findings. ( A and B ) Retroflexed uterus with a heterogeneous myometrium and a posterior wall lesion consistent with adenomyosis, demonstrating asymmetrical myometrial thickening, heterogeneous echotexture, and indistinct junctional zone, in accordance with Morphological Uterus Sonographic Assessment (MUSA) criteria. ( C ) Left ovarian cyst with ground-glass appearance, suggestive of endometrioma. ( D ) Right ovary demonstrating multiple cystic lesions with ground-glass appearance, consistent with multiple endometriomas. ( E ) Hypoechoic nodule in the posterior compartment, suspected to arise from the bowel, suggestive of deep infiltrating endometriosis. ( F ) Tubular hypoechoic mass with internal septations consistent with hydrosalpinx, with negative sliding sign indicating posterior compartment adhesions. Grayscale ultrasound with 6 sub-images (A-F), yellow calipers and measurement tables on black. Transvaginal ultrasound findings. ( A and B ) Retroflexed uterus with a heterogeneous myometrium and a posterior wall lesion consistent with adenomyosis, demonstrating asymmetrical myometrial thickening, heterogeneous echotexture, and indistinct junctional zone, in accordance with Morphological Uterus Sonographic Assessment (MUSA) criteria. ( C ) Left ovarian cyst with ground-glass appearance, suggestive of endometrioma. ( D ) Right ovary demonstrating multiple cystic lesions with ground-glass appearance, consistent with multiple endometriomas. ( E ) Hypoechoic nodule in the posterior compartment, suspected to arise from the bowel, suggestive of deep infiltrating endometriosis. ( F ) Tubular hypoechoic mass with internal septations consistent with hydrosalpinx, with negative sliding sign indicating posterior compartment adhesions. Pelvic magnetic resonance imaging (MRI) was performed using a 3.0-T scanner before and after intravenous contrast administration with T1-weighted, T2-weighted, T2 short tau inversion recovery (STIR), contrast-enhanced T1-weighted fat-suppressed, diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) sequences acquired in axial, sagittal, and coronal planes. MRI demonstrated posterior junctional zone thickening with multiple intramyometrial foci infiltrating the posterior myometrium, consistent with diffuse adenomyosis. Bilateral ovarian cystic lesions and bilateral thick-walled tubular adnexal structures suggestive of salpingitis were also identified, together with a small pelvic fluid collection. However, MRI did not demonstrate definite posterior compartment deep infiltrating endometriosis or pelvic adhesions. The patient subsequently underwent fertility-preserving laparoscopic surgery. Intraoperatively, the uterus appeared globular with diffuse posterior wall thickening consistent with adenomyosis. Grade II–III pelvic adhesions involved the posterior compartment, with dense adhesions between the posterior uterine wall and the rectosigmoid colon, resulting in partial obliteration of the cul-de-sac. Bilateral ovarian endometriomas were identified, measuring approximately 3×2 cm on the right and 4×4 cm on the left. The right ovary was adherent to the ovarian fossa and posterior uterine corpus. The left fallopian tube was markedly dilated, consistent with hydrosalpinx, with fimbrial obliteration and dense adhesions to the ovarian fossa and posterior uterus. A nodular lesion involving the posterior compartment was compatible with deep infiltrating endometriosis ( Figure 2 ). Figure 2 Laparoscopic findings demonstrating advanced endometriosis with posterior compartment involvement. ( A ) Enlarged uterus with irregular serosal surface suggestive of adenomyosis. ( B ) Dense adhesions involving the posterior compartment and pelvic sidewall, consistent with partial obliteration of the cul-de-sac. ( C ) Surgical adhesiolysis and dissection of endometriotic adhesions surrounding the uterus and adnexa. ( D ) Nodular lesion in the posterior compartment compatible with deep infiltrating endometriosis (DIE). ( E ) Ovarian endometrioma with evacuation of characteristic “chocolate-like” fluid. ( F ) Extensive fibrotic and inflammatory tissue in the posterior compartment following excision of deep endometriotic lesions. Part A presents a smooth, rounded visceral structure with a metallic surgical instrument tip at the lower left edge and a small clip at the lower portion of the organ surface, consistent with the uterus displaying an irregular serosal surface. Part B shows a close-up surgical site with a metallic clip centered within dissected tissue, securing a vessel or duct, with surrounding anatomical structures exposed following dissection of endometriotic adhesions surrounding the uterus and adnexa. Part C shows a surgical grasper on the left engaging a rounded, lobulated nodular tissue mass with an irregular surface, representing a nodular lesion in the posterior compartment consistent with deep infiltrating endometriosis. Additional instruments and surrounding structures are present. Part D presents a smooth, rounded tissue structure positioned centrally within the surgical field, surrounded by peritoneal tissue, corresponding to an ovarian endometrioma prior to or following evacuation. Part E shows a deeper dissection with instruments visible and dark fluid present centrally, consistent with evacuation of characteristic fluid from an ovarian endometrioma, with surrounding tissue retracted. Part F presents a close-up of excised tissue with a rough, granular, heterogeneous surface texture, representing extensive fibrotic and inflammatory tissue in the posterior compartment following excision of deep endometriotic lesions. Six-view laparoscopic photograph of pelvic endometriosis with adhesiolysis and endometrioma fluid evacuation. Laparoscopic findings demonstrating advanced endometriosis with posterior compartment involvement. ( A ) Enlarged uterus with irregular serosal surface suggestive of adenomyosis. ( B ) Dense adhesions involving the posterior compartment and pelvic sidewall, consistent with partial obliteration of the cul-de-sac. ( C ) Surgical adhesiolysis and dissection of endometriotic adhesions surrounding the uterus and adnexa. ( D ) Nodular lesion in the posterior compartment compatible with deep infiltrating endometriosis (DIE). ( E ) Ovarian endometrioma with evacuation of characteristic “chocolate-like” fluid. ( F ) Extensive fibrotic and inflammatory tissue in the posterior compartment following excision of deep endometriotic lesions. Laparoscopic adhesiolysis was first performed to restore pelvic anatomy. A left salpingectomy was subsequently undertaken because of severe hydrosalpinx with fimbrial obliteration. Given the patient’s strong desire for future fertility, laparoscopic adenomyomectomy was performed after intramyometrial vasopressin injection, with excision of the dominant posterior adenomyotic lesion followed by multilayer uterine reconstruction using barbed sutures. Bilateral ovarian cystectomy was then completed. Chromopertubation demonstrated free spill through the right fallopian tube, indicating preserved tubal patency. Histopathological examination of the surgical specimens confirmed adenomyosis, characterized by endometrial glands and endometrial stroma embedded within bundles of hypertrophic myometrium. The ovarian cyst was consistent with an endometriotic cyst, demonstrating endometrial glands and stroma with hemosiderin pigment and hemosiderin-laden macrophages. Examination of the fallopian tube identified a paratubal cyst with mild chronic inflammatory cell infiltration without evidence of malignancy. No separate histopathological specimen from the posterior compartment lesion was submitted; therefore, the diagnosis of deep infiltrating endometriosis was established based on the concordance between preoperative imaging and intraoperative findings. Based on the documented operative findings, including bilateral ovarian endometriomas, extensive posterior compartment adhesions with partial cul-de-sac obliteration, and left tubal involvement, the disease was classified as revised American Society for Reproductive Medicine (rASRM) stage IV endometriosis. The reconstructed estimated rASRM score is presented in Table 2 . Table 2 Estimated rASRM Score Based on Documented Intraoperative Findings rASRM Component Documented Intraoperative Finding rASRM Category used Score Right ovarian endometriosis Right ovarian endometrioma 3×2 cm Deep ovarian endometriosis, 1–3 cm 16 Left ovarian endometriosis Left ovarian endometrioma 4×4 cm Deep ovarian endometriosis, >3 cm 20 Right ovarian adhesion Right ovary adherent to ovarian fossa and posterior uterine corpus Dense ovarian adhesion, estimated 1/3–2/3 involvement 8 Left ovarian adhesion Left adnexal mass with adhesions to ovarian fossa and posterior uterus Dense ovarian adhesion, estimated 1/3–2/3 involvement 8 Left tubal adhesion Left hydrosalpinx with fimbrial obliteration and adhesions to ovarian fossa/posterior uterus Dense tubal adhesion with fimbrial involvement 16 Posterior cul-de-sac Posterior uterine adhesion to rectosigmoid with partial cul-de-sac obliteration Partial obliteration 4 Posterior peritoneal disease Posterior compartment DIE involving bowel region Deep peritoneal lesion, estimated 1–3 cm 4 Total estimated rASRM score 76 rASRM stage Stage IV / severe disease >40 Estimated rASRM Score Based on Documented Intraoperative Findings The postoperative course was uneventful. The patient was discharged in stable condition and prescribed dienogest 2 mg once daily for postoperative hormonal suppression while awaiting future fertility treatment. She was counseled regarding future reproductive planning, including the possibility of assisted reproductive technologies, such as intrauterine insemination (IUI) or in vitro fertilization (IVF), depending on subsequent fertility evaluation.

Adenomyosis is a benign gynecological disorder characterized by the presence of endometrial glands and stroma within the myometrium, accompanied by hypertrophy of the surrounding smooth muscle and disruption of the junctional zone. Historically, it has been regarded as a disease affecting multiparous women in later reproductive life and was most commonly diagnosed following hysterectomy. However, advances in non-invasive imaging, particularly transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI), have demonstrated that adenomyosis may occur in younger women and can be diagnosed accurately before surgery using standardized imaging criteria. Recent evidence further highlights that adenomyosis in adolescents and young women remains underrecognized despite increasing awareness, contributing to delayed diagnosis and prolonged symptom burden. 1–6 Increasing evidence suggests that adenomyosis and endometriosis frequently coexist and may represent overlapping manifestations of a common disease spectrum rather than distinct pathological entities. Shared hormonal, inflammatory, genetic, and molecular mechanisms have been proposed to explain their frequent coexistence, while deep infiltrating endometriosis (DIE) has been implicated in the development of adenomyosis through the proposed outside-to-inside invasion mechanism. 1–5 Despite these advances, diagnosis remains challenging in young women because symptoms such as severe dysmenorrhea are often normalized, resulting in delayed referral and progression to advanced disease before definitive diagnosis. 7 , 8 Accurate preoperative assessment is essential for surgical planning and fertility preservation in women with suspected advanced endometriosis. Current international guidelines recommend expert-performed TVUS as the first-line imaging modality, with MRI serving as a complementary investigation for disease mapping and evaluation of lesions beyond the sonographic field of view. 6 , 9 Nevertheless, discrepancies between imaging findings and intraoperative observations continue to occur, particularly in posterior compartment disease and pelvic adhesions, emphasizing the need to understand the complementary strengths and limitations of each modality. 10–18 Herein, we report the case of a 22-year-old nulligravid woman with diffuse adenomyosis coexisting with histopathologically confirmed ovarian endometriomas. This case highlights three clinically relevant lessons: adenomyosis should not be excluded solely because of young age; the coexistence of posterior adenomyosis and posterior DIE provides clinical support for the outside-to-inside pathogenic hypothesis; and discordant findings between TVUS and MRI should be interpreted in the context of their complementary diagnostic roles, with laparoscopy remaining the reference standard for definitive assessment of advanced endometriosis.

This case demonstrates that diffuse adenomyosis can coexist with rASRM stage IV endometriosis in young women and should be considered in patients presenting with persistent dysmenorrhea regardless of age. The close anatomical relationship between posterior adenomyosis and posterior deep infiltrating endometriosis provides clinical support for the outside-to-inside pathogenic hypothesis. The discrepancy between transvaginal ultrasound and magnetic resonance imaging highlights the complementary roles of multimodal imaging, with laparoscopy remaining the reference standard when imaging findings are discordant. Early recognition of persistent dysmenorrhea, prompt referral to specialist care, and comprehensive multimodal imaging assessment are essential to facilitate timely fertility-preserving management before progression to advanced pelvic disease.

The present case illustrates an increasingly recognized phenotype of diffuse adenomyosis coexisting with advanced endometriosis in a young woman. Although adenomyosis has traditionally been regarded as a disease affecting multiparous women in later reproductive life, improvements in imaging have demonstrated that it may occur considerably earlier and frequently coexist with endometriosis. Recent evidence suggests that these disorders share overlapping hormonal, inflammatory, and molecular mechanisms, supporting the concept that they represent different manifestations of a common disease continuum rather than distinct pathological entities. In this patient, diffuse adenomyosis was diagnosed preoperatively using standardized transvaginal ultrasound (TVUS) and magnetic resonance imaging (MRI), confirmed histopathologically, and accompanied by surgically confirmed revised American Society for Reproductive Medicine (rASRM) stage IV endometriosis. Collectively, these findings emphasize three clinically relevant messages: adenomyosis should not be excluded solely because of young age; severe dysmenorrhea warrants early evaluation regardless of patient age; and multimodal imaging should be interpreted in conjunction with surgical findings to optimize management in women desiring future fertility. 1–6 , 8 The coexistence of adenomyosis and deep infiltrating endometriosis (DIE) has stimulated considerable interest regarding their underlying pathogenesis. Two principal mechanisms have been proposed. The tissue injury and repair (TIAR) hypothesis suggests that repeated hormonal and mechanical injury at the endometrial–myometrial interface disrupts the junctional zone, allowing invagination of the basal endometrium into the myometrium and subsequent development of adenomyosis. 2 , 3 In contrast, the outside-to-inside hypothesis proposes that endometriotic implants originating from the peritoneal cavity progressively infiltrate the uterine serosa and outer myometrium, eventually giving rise to adenomyotic lesions. 4 Although both mechanisms may contribute to disease development, the anatomical distribution observed in the present case appears more consistent with the outside-to-inside hypothesis. Diffuse adenomyosis predominantly involved the posterior uterine wall on both TVUS and MRI, while TVUS identified a posterior compartment lesion suspicious for DIE. Laparoscopy subsequently confirmed dense adhesions between the posterior uterus and rectosigmoid colon with partial obliteration of the cul-de-sac, placing extensive posterior compartment disease immediately adjacent to the region of adenomyosis. Although this observation cannot establish causality, the close anatomical relationship between posterior DIE and posterior adenomyosis supports previous reports suggesting that these lesions may represent different stages of a shared pathological process rather than independent diseases. 1–4 Another notable aspect of this case is the advanced extent of disease despite the patient’s young age. Several epidemiological studies have demonstrated that women with affected first-degree relatives have a substantially increased lifetime risk of endometriosis, highlighting the contribution of shared genetic susceptibility and epigenetic regulation. 5 In the present case, the patient’s mother had a history of severe dysmenorrhea, raising the possibility of inherited susceptibility. More importantly, this family history may also have influenced the patient’s perception that severe menstrual pain represented a normal familial experience rather than a symptom requiring medical evaluation. Such normalization of dysmenorrhea is recognized as an important contributor to delayed diagnosis in endometriosis. Current evidence suggests that women frequently experience a diagnostic delay of approximately 7–10 years between symptom onset and definitive diagnosis, particularly during adolescence and early reproductive life when symptoms are often attributed to primary dysmenorrhea. 6 , 8 Although the exact duration of symptoms in this patient cannot be determined retrospectively, prolonged normalization of severe dysmenorrhea likely delayed referral and specialist evaluation, allowing progression to extensive posterior compartment adhesions, bilateral ovarian endometriomas, severe tubo-ovarian distortion, and rASRM stage IV disease. These findings reinforce the importance of early assessment of persistent dysmenorrhea, particularly in young women with a positive family history of endometriosis or adenomyosis, to facilitate diagnosis before irreversible pelvic anatomical distortion develops. Accurate preoperative assessment of adenomyosis and deep infiltrating endometriosis (DIE) is essential for surgical planning, patient counseling, and fertility preservation. Current international guidelines recommend expert-performed transvaginal ultrasound (TVUS) as the first-line imaging modality for women with suspected endometriosis because of its accessibility, dynamic assessment, and high diagnostic performance, whereas magnetic resonance imaging (MRI) serves as a complementary examination when ultrasound findings are inconclusive, disease mapping is incomplete, or lesions beyond the sonographic field of view are suspected. 6 , 7 Published evidence comparing the diagnostic performance of TVUS and MRI is summarized in Table 3 . Table 3 Summary of Comparative Studies Evaluating Transvaginal Ultrasound and Magnetic Resonance Imaging for Deep Infiltrating Endometriosis Study Design (N) Disease Site Main Findings Interpretation Abrao et al (2007) 13 Prospective (104) Rectosigmoid, rectovaginal septum TVUS demonstrated higher diagnostic accuracy than MRI for rectosigmoid (99.0% vs 90.3%) and rectovaginal disease (97.0% vs 71.0%). TVUS superior for posterior compartment lesions. Bazot et al (2009) 12 Retrospective (92) USL, vagina, intestine MRI showed higher sensitivity for uterosacral ligament and vaginal DIE, whereas TVUS demonstrated slightly higher accuracy for intestinal involvement. Diagnostic performance depends on lesion location. Saccardi et al (2012) 14 Prospective (102 suspected; 54 operated) Posterior compartment MRI combined with saline contrast sonovaginography improved detection of posterior DIE compared with conventional TVUS. MRI superior when combined with contrast-enhanced techniques. Vimercati et al (2012) 19 Prospective (90) Overall DIE, rectosigmoid nodules, pelvic adhesions TVUS showed comparable or higher diagnostic accuracy for DIE and rectosigmoid lesions, whereas contrast-enhanced MR colonography was more accurate for pelvic adhesions. TVUS effective for bowel DIE; CE-MR colonography may better characterize adhesions. Hernández-Gutiérrez et al (2019) 15 Retrospective (48) Rectovaginal septum, vagina, bladder TVUS achieved higher diagnostic accuracy for rectovaginal and vaginal lesions, while MRI showed better performance for bladder involvement. TVUS and MRI are complementary according to disease location. Bielen et al (2020) (IDEAL Study) 16 Prospective observational (74) Overall pelvic DIE One-stop MRI and expert TVUS demonstrated comparable performance for disease mapping before surgery. Both modalities provide reliable preoperative assessment. Roditis et al (2023) 17 Retrospective (178) USL, vagina, rectosigmoid, bladder MRI showed higher sensitivity for uterosacral ligament and bladder lesions, whereas TVUS demonstrated comparable performance for rectosigmoid disease. The combined imaging approach achieved the highest diagnostic accuracy. Combined TVUS and MRI provides the most comprehensive evaluation. O’Leary et al (2025) 10 Systematic review Overall DIE Expert-performed TVUS and MRI showed comparable overall diagnostic performance. Selection should be guided by clinical indication, lesion location, and operator expertise. TVUS should be the first-line examination, with MRI serving as a complementary modality. Abbreviations : TVUS, transvaginal ultrasound; MRI, magnetic resonance imaging; DIE, deep infiltrating endometriosis; USL, uterosacral ligament; CE-MR colonography, contrast-enhanced magnetic resonance colonography. Summary of Comparative Studies Evaluating Transvaginal Ultrasound and Magnetic Resonance Imaging for Deep Infiltrating Endometriosis Abbreviations : TVUS, transvaginal ultrasound; MRI, magnetic resonance imaging; DIE, deep infiltrating endometriosis; USL, uterosacral ligament; CE-MR colonography, contrast-enhanced magnetic resonance colonography. Overall, comparative studies demonstrate that TVUS and MRI provide comparable diagnostic performance for ovarian endometriomas and deep infiltrating endometriosis, with neither modality consistently demonstrating overall superiority. Instead, diagnostic performance depends on lesion location, disease extent, and operator expertise. Several studies have reported that expert-performed TVUS achieves sensitivity and specificity comparable to MRI for detecting DIE and may outperform MRI in identifying posterior compartment disease, pouch of Douglas obliteration, and pelvic adhesions through dynamic assessment of organ mobility. Conversely, MRI offers superior soft-tissue contrast and comprehensive pelvic mapping, making it particularly valuable for evaluating multifocal disease, anterior compartment involvement, and complex preoperative surgical planning. 7 , 9–17 The present case closely reflects these complementary characteristics. TVUS accurately demonstrated diffuse adenomyosis according to the Morphological Uterus Sonographic Assessment (MUSA) criteria, bilateral ovarian endometriomas, a posterior compartment lesion suspicious for deep infiltrating endometriosis (DIE), and a negative sliding sign suggesting posterior compartment adhesions. These posterior compartment findings were subsequently confirmed during laparoscopy. MRI confirmed diffuse adenomyosis through posterior junctional zone thickening with multiple intramyometrial foci and accurately characterized the bilateral adnexal lesions. In this case, TVUS provided superior assessment of posterior compartment disease, whereas MRI primarily delineated uterine and adnexal pathology. Importantly, this difference should not be interpreted as a diagnostic failure of MRI but rather as a reflection of the complementary strengths of the two imaging modalities. Unlike MRI, which provides static anatomical assessment, TVUS allows real-time dynamic evaluation of pelvic organ mobility. Assessment of the sliding sign enables indirect identification of adhesions and obliteration of the pouch of Douglas, findings that cannot be directly evaluated using conventional MRI. Consequently, subtle fibrotic adhesions and early posterior compartment fixation may remain occult on MRI despite otherwise excellent anatomical visualization. In the present case, the negative sliding sign accurately predicted dense posterior compartment adhesions that were subsequently confirmed laparoscopically, illustrating the additional diagnostic value of dynamic ultrasound. These findings are consistent with published comparative studies and reinforce the complementary rather than competitive roles of TVUS and MRI in the preoperative evaluation of advanced endometriosis. Therefore, when imaging findings are discordant but clinical suspicion remains high, laparoscopic assessment should remain the reference standard for definitive diagnosis and treatment planning. 6 , 7 , 9–17 Histopathological examination confirmed both adenomyosis and ovarian endometrioma, supporting the preoperative imaging and intraoperative diagnoses. The tubal specimen demonstrated a paratubal cyst with mild chronic inflammatory cell infiltration without evidence of malignancy. Although the gross intraoperative appearance was consistent with severe hydrosalpinx, the histopathological findings reflected only the submitted specimen and therefore should not be interpreted as contradictory. Gross surgical assessment represents the overall morphology of the tubo-ovarian complex, whereas histopathological examination is limited to the tissue submitted for microscopic evaluation. In advanced endometriosis, chronic inflammation, fibrosis, and distortion of normal pelvic anatomy frequently complicate direct clinicopathological correlation. Accordingly, imaging, operative findings, and histopathology should be interpreted collectively to achieve the most accurate diagnosis. 1–4 The coexistence of diffuse adenomyosis and rASRM stage IV endometriosis in a 22-year-old woman has important implications for future reproductive potential. In the present case, bilateral ovarian endometriomas, severe posterior compartment adhesions, tubo-ovarian distortion, and left hydrosalpinx requiring salpingectomy indicated advanced pelvic disease despite the patient’s young age. These anatomical abnormalities may impair natural fertility, while adenomyosis involving the junctional zone has been associated with reduced endometrial receptivity and impaired reproductive outcomes. 1 , 2 , 18 Because the patient desired future pregnancy, fertility-preserving laparoscopic surgery consisting of adenomyomectomy, bilateral ovarian cystectomy, adhesiolysis, and unilateral salpingectomy was performed. This case therefore highlights the importance of early recognition of persistent dysmenorrhea and timely referral for expert imaging before progression to advanced disease compromises reproductive potential. Because the patient strongly desired future fertility, conservative surgery was selected. Fertility-preserving adenomyomectomy has evolved considerably over recent years, with increasing emphasis on individualized patient selection, meticulous multilayer uterine reconstruction, and postoperative hormonal suppression to optimize symptom control and reproductive outcomes. Although diffuse adenomyosis remains technically challenging to excise completely, conservative surgery may provide symptomatic improvement in carefully selected young women wishing to preserve fertility. 20 , 21 The principal strength of this report is the comprehensive clinicoradiological correlation achieved through standardized TVUS using MUSA criteria, MRI, laparoscopic assessment, and histopathological confirmation of adenomyosis and ovarian endometrioma. Furthermore, integration of published comparative studies ( Table 3 ) places the observed imaging discrepancy within the context of current evidence and provides practical guidance for interpreting discordant imaging findings in women with suspected advanced endometriosis. Several limitations should also be acknowledged. As a single case report, the findings cannot establish causal relationships between posterior DIE and adenomyosis or determine the superiority of one imaging modality over another. In addition, histopathological confirmation of the posterior compartment lesion was unavailable because no separate specimen was submitted for pathological examination. Nevertheless, the concordance between clinical presentation, multimodal imaging, and laparoscopic findings provides a comprehensive illustration of the diagnostic challenges encountered in young women with coexisting adenomyosis and advanced endometriosis.