Malignant transformation of pelvic endometriosis: MR imaging findings and pathologic correlation

Endometriosis: assessment on O-RADS and risk of malignant transformation

Endometriosis is a common disease, affecting approximately 10% of women of reproductive age. Several intersecting guidelines and consensus statements provide information on imaging diagnosis and surveillance strategies for endometriomas. SRU consensus panel recommendations provide information on initial detection of endometriosis on routine pelvic imaging. Revised American Society of Reproductive Medicine (rASRM) classification, the #ENZIAN classification, and the deep pelvic endometriosis index (dPEI) aim to assess the overall extent of disease and assist in presurgical planning. The Ovarian-Adnexal Reporting and Data System (O-RADS) aims to risk stratify lesions evaluated with US or MR based on their imaging morphology, from typical benign lesions to atypical presentations and malignant transformation. Emerging data shows increased risk of ovarian cancer in patients with endometriosis, especially following menopause and in those patients with long standing endometriosis. (Chen et al. in Front Oncol. 14:1329133, 2024;Streuli et al. in Climacteric. 20:138-143, 2017;Secosan et al. in Diagnostics (Basel). 10:134, 2020;Inceboz in Womens Health (Lond Engl). 11:711-715, 2015;Cassani et al. in Maturitas. 190, 2024;Gemmell et al. in Hum Reprod Update. 23:481-500, 2017;Giannella et al. in Cancers (Basel). 13:4026, 2021;) Current O-RADS guidelines mandate follow-up of endometriomas up to 2 years with further follow-up based on clinical factors. No consensus guidelines exist for imaging surveillance of patients with deep endometriosis from a malignancy standpoint. This review explores the imaging appearance of endometriomas, imaging features of malignant transformation, surveillance strategies and gaps in current literature, and attempts to better understand the risk of malignancy and to encourage further research for long-term imaging surveillance of endometriosis patients.

Fallopian fimbriae entrapped in an ovarian endometriotic cyst mimicking malignancy: a case report

Ovarian endometriotic cysts are associated with an increased risk of clear cell and endometrioid carcinomas, as well as borderline neoplasms. Although contrast-enhancing nodules on magnetic resonance imaging (MRI) suggest malignancy, benign endometriotic cysts can also present with such features, complicating differentiation from malignancy. When malignancy is suspected, minimally invasive procedures, such as laparoscopic cystectomy, are typically avoided. However, preserving fertility and ovarian function warrants careful consideration when selecting invasive surgical procedures. From the perspective of selecting appropriate surgical approaches, accurate preoperative differentiation between benign and malignant ovarian tumors is essential. We present the first case of MRI showing fallopian fimbriae entrapped in an endometriotic cyst mimicking malignancy. A 49-year-old female presented with atypical genital bleeding. MRI revealed a right ovarian endometriotic cyst with a contrast-enhancing mural nodule (10 mm), suggestive of malignancy. The nodule demonstrated T2-weighted hypointensity equivalent to the cyst fluid without diffusion restriction. Laparotomy revealed the nodule as entrapped fallopian fimbriae within the endometriotic cyst, with no malignancy detected. In this case, the fallopian fimbriae entrapped in the endometriotic cyst appeared as an enhancing nodule because of their vascularity, mimicking malignancy. Fallopian fimbriae are inconspicuous structures that can produce false findings suggestive of malignancy, similar to other benign enhancing nodules, such as polypoid endometriosis and decidualization. However, their lack of diffusion restriction and low T2-weighted signal intensity may help distinguish them from malignancy. This knowledge is crucial for accurate diagnosis and avoiding unnecessary interventions.

Pathology and risk stratification-based evaluation of ovarian masses on MRI

Characterisation of an indeterminate ovarian mass is important as it guides management and clinical outcomes. Ultrasound is the first-line modality in the assessment of ovarian tumours. When ovarian masses are indeterminate on ultrasound, MRI provides excellent resolution in tissue characterisation and enhancement patterns. Ovarian masses can be categorised based on risk-scoring systems such as the American College of Radiology (ACR) MRI Ovarian-Adnexal Reporting and Data System (O-RADS). The imaging features of non-neoplastic, benign, borderline and malignant neoplastic ovarian lesions are discussed in this review with a focus on the pathology process accounting for the MRI appearance. Characteristic findings and clues in differentiating a benign lesion from a malignancy are presented in this review.

Postmenopausal Endometriosis: Clinical Insights and Imaging Considerations

Endometriosis is a chronic systemic condition characterized by the presence of ectopic endometrial-like tissue outside of the uterus. It occurs most often in reproductive-aged patients and less frequently in postmenopausal women. In postmenopausal patients, endometriosis is more common in those undergoing hormone replacement therapy or taking tamoxifen. The risk of malignant transformation of endometriosis is higher in this older population, especially in those undergoing estrogen-only hormone replacement therapy. Many theories on the postmenopausal pathogenesis of endometriosis have been proposed, ranging from reactivation of premenopausal disease to de novo manifestation. Compared with premenopausal disease, postmenopausal endometriosis is typically less active and extensive, with fewer hemorrhagic components. Patients may be symptomatic, with chronic pelvic pain, or may receive the diagnosis after imaging performed for other indications such as an incidental ovarian lesion. Treatment is typically surgical resection or estrogen-blocking medications. Although the diagnosis requires pathologic confirmation, radiologists play an important role in diagnosing both benign endometriosis and malignant transformation. Pelvic US following a dedicated protocol is an accessible screening tool, with high sensitivity for diagnosis of bowel-invasive disease. MRI has better anatomic resolution and allows simultaneous characterization of adnexal and extrapelvic lesions, thereby providing excellent assessment for malignant transformation.

Endometriosis, a common but enigmatic disease with many faces: current concept of pathophysiology, and diagnostic strategy

Endometriosis is a benign, common, but controversial disease due to its enigmatic etiopathogenesis and biological behavior. Recent studies suggest multiple genetic, and environmental factors may affect its onset and development. Genomic analysis revealed the presence of cancer-associated gene mutations, which may reflect the neoplastic aspect of endometriosis. The management has changed dramatically with the development of fertility-preserving, minimally invasive therapies. Diagnostic strategies based on these recent basic and clinical findings are reviewed. With a focus on the presentation of clinical cases, we discuss the imaging manifestations of endometriomas, deep endometriosis, less common site and rare site endometriosis, various complications, endometriosis-associated tumor-like lesions, and malignant transformation, with pathophysiologic conditions.

Pathophysiology and Clinical Implications of Ovarian Endometriomas

Ovarian endometriomas affect many patients with endometriosis and have significant effects on quality of life, fertility, and risk of malignancy. Endometriomas range from small (1-3 cm), densely fibrotic cysts to large (20 cm or greater) cysts with varying degrees of fibrosis. Endometriomas are hypothesized to form from endometriotic invasion or metaplasia of functional cysts or alternatively from ovarian surface endometriosis that bleeds into the ovarian cortex. Different mechanisms of endometrioma formation may help explain the phenotypic variability observed among endometriomas. Laparoscopic surgery is the preferred first-line modality of diagnosis and treatment of endometriomas. Ovarian cystectomy is preferred over cyst ablation or sclerotherapy for enabling pathologic diagnosis, improving symptoms, preventing recurrence, and optimizing fertility outcomes. Cystectomy for small, densely adherent endometriomas is made challenging by dense fibrosis of the cyst capsule obliterating the plane with normal ovarian cortex, whereas cystectomy for large endometriomas can carry unique challenges as a result of adhesions between the cyst and pelvic structures. Preoperative and postoperative hormonal suppression can improve operative outcomes and decrease the risk of endometrioma recurrence. Whether the optimal management, fertility consequences, and malignant potential of endometriomas vary on the basis of size and phenotype remains to be fully explored.

MR Relaxometry for Discriminating Malignant Ovarian Cystic Tumors: A Prospective Multicenter Cohort Study

BACKGROUND

Endometriosis-associated ovarian cancer (EAOC) is a well-known type of cancer that arises from ovarian endometrioma (OE). OE contains iron-rich fluid in its cysts due to repeated hemorrhages in the ovaries. However, distinguishing between benign and malignant tumors can be challenging. We conducted a retrospective study on magnetic resonance (MR) relaxometry of cyst fluid to distinguish EAOC from OE and reported that this method showed good accuracy. The purpose of this study is to evaluate the accuracy of a non-invasive method in re-evaluating pre-surgical diagnosis of malignancy by a prospective multicenter cohort study.

METHODS

After the standard diagnosis process, the R2 values were obtained using a 3T system. Data on the patients were then collected through the Case Report Form (CRF). Between December 2018 and March 2023, six hospitals enrolled 109 patients. Out of these, 81 patients met the criteria required for the study.

RESULTS

The R2 values calculated using MR relaxometry showed good discriminating ability with a cut-off of 15.74 (sensitivity 80.6%, specificity 75.0%, AUC = 0.750, p < 0.001) when considering atypical or borderline tumors as EAOC. When atypical and borderline cases were grouped as OE, EAOC could be distinguished with a cut-off of 16.87 (sensitivity 87.0%, specificity 61.1%).

CONCLUSIONS

MR relaxometry has proven to be an effective tool for discriminating EAOC from OE. Regular use of this method is expected to provide significant insights for clinical practice.

Pictorial essay: MRI evaluation of endometriosis-associated neoplasms

Endometriosis is a frequent pathology mostly affecting women of young age. When typical aspects are present, the diagnosis can easily be made at imaging, especially at MRI. Transformation of benign endometriosis to endometriosis-associated neoplasms is rare. The physiopathology is complex and remains controversial. Endometrioid carcinoma and clear cell carcinoma are the main histological subtypes. Our goal was to review the main imaging characteristics that should point to an ovarian or extra-ovarian endometriosis-related tumor, especially at MRI, as it may be relevant prior to surgical management.Key points• Transformation of benign endometriosis to endometriosis-associated neoplasms is rare.• MRI is useful when displaying endometriosis lesions associated to an ovarian tumor.• Subtraction imaging should be used in the evaluation of complex endometriomas.

Ovarian cancer during pregnancy

Adnexal masses during pregnancy are a relatively uncommon entity. Their clinical management is challenging given the overlapping features of certain entities on imaging and histopathology, which can mimic malignancy, and the potential side effects to the mother and fetus, whether expectant management versus surgery is pursued. Ultrasonography with Doppler evaluation is the modality of choice for evaluating adnexal masses during pregnancy. Magnetic resonance imaging is the second-line modality useful when US findings are inconclusive/indeterminate. Most adnexal masses in pregnant patients are benign in origin (e.g., functional cysts, mature cystic teratoma, decidualization of endometrioma), but a few are malignant in origin (e.g., dysgerminoma, granulosa cell tumor). Most cases of adnexal masses are asymptomatic, but complications such as ovarian torsion can occur. This review aims to familiarize the radiologist with the imaging of adnexal lesions during pregnancy so that the radiologist can identify ovarian cancer. Specifically, the review will detail the most common benign and malignant adnexal masses in pregnancy, mimickers, and their corresponding imaging findings on US and MRI.

A case of endometriotic cyst enlargement during pregnancy owing to desmoplasia and rupture at 36 weeks of gestation

Decidualized ovarian endometrioma is a rare phenomenon that occurs during pregnancy. A 43-year-old pregnant woman with an endometriotic cyst increased owing to desmoplasia presented to us urgently with abdominal pain and was performed a cesarean section at 36 weeks and 1 day of pregnancy. The left ovarian cyst was noted to be partially ruptured, and the pathological diagnosis was an endometriotic cyst with desmoplasia. Endometriotic cysts may enlarge during pregnancy owing to desmoplasia and rupture in the last trimester of pregnancy, causing acute abdomen.

The Endometriotic Neoplasm Algorithm for Risk Assessment (e-NARA) Index Sheds Light on the Discrimination of Endometriosis-Associated Ovarian Cancer from Ovarian Endometrioma

BACKGROUND

Magnetic resonance (MR) relaxometry provides a noninvasive tool to discriminate endometriosis-associated ovarian cancer (EAOC) from ovarian endometrioma (OE) with high accuracy. However, this method has a limitation in discriminating malignancy in clinical use because the R2 value depends on the device manufacturer and repeated imaging is unrealistic. The current study aimed to reassess the diagnostic accuracy of MR relaxometry and investigate a more powerful tool to distinguish EAOC from OE.

METHODS

This retrospective study was conducted at our institution from December, 2012, to May, 2022. A total of 150 patients were included in this study. Patients with benign ovarian tumors (n = 108) mainly received laparoscopic surgery, and cases with suspected malignancy (n = 42) underwent laparotomy. Information from a chart review of the patients' medical records was collected.

RESULTS

A multiple regression analysis revealed that the age, the tumor diameter, and the R2 value were independent malignant predicting factors. The endometriotic neoplasm algorithm for risk assessment (e-NARA) index provided high accuracy (sensitivity, 85.7%; specificity, 87.0%) to discriminate EAOC from OE.

CONCLUSIONS

The e-NARA index is a reliable tool to assess the probability of malignant transformation of endometrioma.

The efficiency of susceptibility-weighted MRI in the differentiation of endometriomas from haemorrhagic ovarian cysts

OBJECTIVES

The aim of the study was to investigate the efficiency of susceptibility-weighted magnetic resonance (MR) imaging (SWIs) in differentiating endometriomas from haemorrhagic ovarian cysts.

MATERIALS AND METHODS

Between July 2017 and January 2019, 89 ovarian cystic lesions (57 endometriomas and 32 haemorrhagic cysts) that were identified as complicated cystic lesions on ultrasonography (US) and underwent lower abdominal MRI with susceptibility weighting were retrospectively evaluated. Final diagnoses were obtained with surgical pathological correlation and radiological-clinical follow-up. Two radiologists blinded to the final diagnoses retrospectively reviewed the images in consensus. The signal intensity on T1- and T2-weighted images and curved linear or punctate signal void areas on SWI were noted for the presence of lesions.

RESULTS

Forty of the 57 endometriomas demonstrated the defined MRI criteria, including a cystic hyperintensity on T1-weighted images and hypointensity on T2-weighted images. The remaining 17 lesions did not demonstrate these criteria on conventional MR images. SWI showed punctate or curved linear signal void areas in 53 of 57 endometriomas (92.9%) and none of the haemorrhagic cysts. The sensitivity, specificity and accuracy of SWI in differentiating endometrioma from haemorrhagic cyst were 92.9%, 100.0%, and 95.5%, respectively.

CONCLUSIONS

The addition of the SWI sequence to conventional MRI can help distinguish endometriomas from haemorrhagic ovarian cysts.

Differentiation between endometriosis-associated ovarian cancers and non- endometriosis-associated ovarian cancers based on magnetic resonance imaging

OBJECTIVES

Endometriosis-associated ovarian cancer (EAOC) patients show different clinical characteristics compared with non-EAOC patients. However, a few studies are focused on the imaging characteristics of EAOC until now. We assessed MRI characteristics in differentiating EAOC and non-EAOC.

METHODS

We retrospectively analyzed clinical and MRI characteristics from 54 patients with 67 lesions diagnosed with primary epithelial ovarian carcinoma at the Third Affiliated Hospital of Guangzhou Medical University between January 2012 and October 2020. We studied MRI findings such as maximum diameter, morphology, configuration, locularity, features of mural nodules, lymphadenopathy, peritoneal implants, the presence of hyperintensity on T1WI, and hypointensity on T2WI. We also studied the clinical characteristics. Significant MRI variables in univariate analysis were selected for subsequent multivariate regression analysis. This study evaluated the diagnostic performance of the significant MRI variables in univariate analysis.

RESULTS

We found that the patients with EAOC, compared with those with non-EAOC, were younger, more unilateral, and had earlier FIGO stage. Univariate analysis revealed that morphology, locularity, growth pattern of mural nodules, and hypointensity on T2WI were factors that significantly differed between EAOC and non-EAOC. In the multivariate logistic regression analysis, locularity and hypointensity on T2WI were independent predictors to distinguish EAOC from non-EAOC.

CONCLUSIONS

EAOC typically presented as a unilocular mass with hypointensity on T2WI in cystic components. MRI could help distinguish EAOC from non-EAOC.

ADVANCES IN KNOWLEDGE

MRI is a promising tool for preoperative diagnosis of EAOC.

Primary diaphragmatic clear cell carcinoma associated with endometriosis: A case report and literature review

Diaphragmatic endometriosis is extremely rare. Although endometriosis is considered generally benign, malignant transformation of endometriosis was reported in 1925. Multiple studies have since described clear cell carcinoma (CCC) or endometrioid carcinoma arising from ovarian endometriosis. Previously, only two reports of primary diaphragmatic CCC were reported, in which coexistent endometriosis with CCC was not histologically proven. We report a case of a 55-year-old postmenopausal woman who was admitted to Kindai university hospital for the examination of a cystic mass with papillary components in the right diaphragm. On her past medical history, abdominal hysterectomy and bilateral salpingo-oophorectomy was performed for high-grade cervical intraepithelial neoplasia, uterine myoma, and bilateral ovarian endometriosis 5 years ago. Unenhanced CT performed 5 years ago, showed a nodular lesion with low density in the right diaphragm, consistent with diaphragmatic endometriosis. Magnetic resonance imaging during this admission, showed a cystic mass with papillary components in the right diaphragm and a T2*-weighted gradient echo imaging showed partial low signal intensity in the papillary components and cyst wall, which was suspected to represent hemosiderin deposition. Based on these serial images, malignant transformation of diaphragmatic endometriosis was suspected. Under, open abdominal combined resection of the mass and part of the diaphragm was performed. Endometriosis implants were detected on the pelvic peritoneum. Histopathological examination revealed clear cell carcinoma associated with endometriosis and hemosiderin deposition in the cyst wall. T2*-weighted gradient echo imaging was useful in the detection of hemosiderin deposition caused by the coexistent endometriosis. When a cystic mass with papillary components and cyst wall with hemosiderin deposits are encountered on MR images, malignant transformation of endometriosis is suspected and a detailed medical history should be determined and the possibility of concurrent endometriosis or adenomyosis should be investigated, as should the potential existence of diaphragmatic endometriosis in previous images.

MRI for the diagnosis and staging of deeply infiltrating endometriosis: a national survey of BSGE accredited endometriosis centres and review of the literature

OBJECTIVES

Our objective was to establish the primary mode of imaging and MR protocols utilised in the preoperative staging of deeply infiltrating endometriosis in centres accredited by the British Society of Gynaecological Endoscopy (BSGE).

METHODS

The lead consultant radiologist in each centre was invited to complete an online survey detailing their protocols.

RESULTS

Out of 49 centres, 32 (65%) responded to the survey. Two centres performed transvaginal ultrasound as the primary method for preoperative staging of deeply infiltrating endometriosis and the remainder performed MRI. 21/25 centres did not recommend a period of fasting prior to MRI and 22/25 administered hyoscine butylbromide. None of the centres routinely offered bowel preparation or recommended a specific pre-procedure diet. 21/25 centres did not time imaging according to the woman's menstrual cycle, and instructions regarding bladder filling were varied. Rectal and vaginal opacification methods were infrequently utilised. All centres preferentially performed MRI in the supine position - six used an abdominal strap and four could facilitate prone imaging. Just under half of centres used pelvic-phased array coils and three centres used gadolinium contrast agents routinely. All centres performed T1W with fat-suppression and T2W without fat-suppression sequences. There was significant variation relating to other MR sequences depending on the unit.

CONCLUSIONS

There was significant inconsistency between centres in terms of MR protocols, patient preparation and the sequences performed. Many practices were out of line with current published evidence.

ADVANCES IN KNOWLEDGE

Our survey demonstrates a need for evidence-based standardisation of imaging in BSGE accredited endometriosis centres.

Encyclopedia of endometriosis: a pictorial rad-path review

Endometriosis affects approximately 10% of reproductive age women and represents a significant cause of pelvic pain and infertility. Unfortunately, the diagnosis of endometriosis is often delayed by years. Endometriosis may manifest as cystic lesions in the ovaries known as endometriomas. Superficial endometriosis is typically detected by laparoscopy along the pelvic peritoneum as these lesions tend to be difficult to detect by imaging. Deep infiltrative endometriosis may be detected by ultrasound, CT or MRI in classic locations within the pelvis, such as the posterior cul-de-sac and uterosacral ligaments. Endometriosis may also involve the thorax, gastrointestinal and urinary tracts, and locations such as the abdominal wall and abdominal organs. We present MRI and CT case examples, together with corresponding laparoscopic and histopathology images to enhance radiologists' understanding of this disease.

Understanding malignant transformation of endometriosis: imaging features with pathologic correlation

PURPOSE

Transformation of benign endometriosis to endometriosis-associated ovarian carcinoma (EAOC) is rare; however, women with endometriosis are four times more likely to develop EAOC which can present 20 years earlier than de novo ovarian cancer. Presenting symptoms are often vague and the radiologist's role in recognizing EAOC is critical for early detection and treatment. Histopathologic evaluation remains the mainstay for definitive diagnosis.

METHODS

Using a case-based approach, this article will review the sonographic, CT, and MRI features of EAOC with an emphasis on MRI. Histopathologic correlation of benign and malignant endometriosis will be reviewed.

RESULTS

Multiple factors contribute to the malignant transformation of endometriosis including genetic alterations, hormonal influences, oxidative stress, and inflammation. Malignancy most often occurs in ovarian endometriomas with less common sites involving the rectovaginal septum, rectosigmoid colon, and abdominal wall scars. The most common pathologic subtypes are endometrioid adenocarcinoma and clear cell carcinoma. MRI is the most specific imaging modality for evaluating EAOC. Key MR features include solid enhancing nodules (accentuated by subtraction imaging), nodular septations, loss of T2 shading within the endometrioma, and diffusion restriction.

CONCLUSIONS

EAOC is a distinct disease that affects women with benign endometriosis at younger ages than classic ovarian cancer. Understanding the imaging features of malignant transformation of endometriosis is essential for early diagnosis and timely definitive treatment.

Recommendations for MRI technique in the evaluation of pelvic endometriosis: consensus statement from the Society of Abdominal Radiology endometriosis disease-focused panel

Endometriosis is a common entity causing chronic pain and infertility in women. The gold standard method for diagnosis is diagnostic laparoscopy, which is invasive and costly. MRI has shown promise in its ability to diagnose endometriosis and its efficacy for preoperative planning. The Society of Abdominal Radiology established a Disease-Focused Panel (DFP) to improve patient care for patients with endometriosis. In this article, the DFP performs a literature review and uses its own experience to provide technical recommendations on optimizing MRI Pelvis for the evaluation of endometriosis.

Use of tumor markers to distinguish endometriosis-related ovarian neoplasms from ovarian endometrioma

OBJECTIVE

Only few studies have focused on tumor markers used in the preoperative diagnosis of endometriosis-related ovarian neoplasms, and previous studies have only assessed serum CA125 levels. This study investigated the significance of preoperative tumor markers and clinical characteristics in distinguishing endometriosis-related ovarian neoplasms from ovarian endometrioma.

METHODS

A case-control study was conducted on 283 women who were diagnosed with confirmed pathology with endometriosis-related ovarian neoplasms (n=21) and ovarian endometrioma (n=262) at a single institution from April 2008 to April 2018. The serum CA125, CA19-9, carcinoembryogenic antigen (CEA), sialyl Lewis-x antigen (SLX), and lactate dehydrogenase (LDH) levels, age, tumor size, and the presence of mural nodule of the patients were analyzed.

RESULTS

Patients with endometriosis-related ovarian neoplasms were more likely to be older (48 (range, 26-81) vs 39 (range, 22-68) years, P<0.001), have higher levels of CA19-9 (42 vs 19 U/mL, P=0.013), CEA (1.3 vs 0.84 ng/mL, P=0.007), SLX (41 vs 33 U/mL, P=0.050), and LDH (189 vs 166 U/mL, P<0.001) and larger tumor size (79 vs 55 mm, P=0.001), and present with mural nodule (85.7 vs 4.5 %, P<0.001) than those with ovarian endometrioma. The CA125 levels did not significantly differ between the two groups. The area under the curve for each factor was as follows: CA19-9 level, 0.672 (95% CI 0.52 to 0.83; P=0.013); CEA level, 0.725 (95% CI 0.58 to 0.87; P=0.007); SLX level, 0.670 (95% CI 0.53 to 0.84; P=0.050); LDH level, 0.800 (95% CI 0.70 to 0.90; P<0.001); age, 0.775 (95% CI 0.65 to 0.90; P<0.001); and tumor size, 0.709 (95% CI 0.56 to 0.86; P=0.001). Age was a better marker than CA19-9, CEA, and SLX levels according to the receiver operating characteristic curve analysis. The optimal cut-off values for age and tumor size were 47 years and 80 mm, respectively.

CONCLUSIONS

The assessment of serum CA19-9, CEA, SLX, and LDH levels may be a useful tool in the preoperative evaluation to differentiate between endometriosis-related ovarian neoplasms and ovarian endometrioma.

MR findings for differentiating decidualized endometriomas from seromucinous borderline tumors of the ovary

PURPOSE

Decidualized endometriomas (DEs) and seromucinous borderline tumors (SMBTs) exhibit similar MR findings including markedly hyperintense mural nodules within endometriotic cysts on T2-weighted images. The present study aimed to assess the efficacy of MR imaging for differentiating between DEs and SMBTs of the ovary.

MATERIALS AND METHODS

MR images of 8 DEs and 14 SMBTs were retrospectively assessed and compared according to pathologies.

RESULTS

With regard to quantitative assessments of mural nodules, the number and signal intensity ratios (SIRs) on T1-weighted images were significantly greater in DEs than in SMBTs (11.0 ± 8.4 vs. 4.3 ± 4.1, p < 0.05 and 2.36 ± 0.56 vs. 1.49 ± 0.27, p < 0.01, respectively), whereas the height was significantly lower in DEs than in SMBTs (4.5 ± 1.4 mm vs. 21.9 ± 11.4 mm, p < 0.01). However, there were no significant differences between DEs and SMBTs in the SIRs on T2-weighted images, SIRs on diffusion-weighted images, and apparent diffusion coefficient values. With regard to qualitative assessments of mural nodules, the lobulated margin, pedunculated configuration, and T2 hypointense core were significantly more frequent in SMBTs than in DEs (71% vs. 0%, p < 0.01; 86% vs. 0%, p < 0.01; and 43% vs. 0%, p < 0.05, respectively).

CONCLUSION

The number, height, SIRs on T1-weighted images, lobulated margin, pedunculated configuration, and T2 hypointense core of mural nodules within endometriotic cysts were useful MR findings for differentiating DEs from SMBTs.

Endometriosis Malignant Transformation Review: Rhabdomyosarcoma Arising From an Endometrioma

Background:

Endometriosis is a widely known benign disease, but 0.5%–1% of cases are associated with malignancy. It has been linked with ovarian neoplasms, particularly endometrioid and clear cell adenocarcinoma histology. Rhabdomyosarcomas are rarely associated with endometriosis.

Case:

A 35-year-old patient underwent surgical management of endometriomas to optimize infertility treatment. She later developed abdominal pain with rapid recurrence of ovarian masses. This prompted additional surgery with biopsies diagnosing ovarian rhabdomyosarcoma. Retroactive review of pathologic specimens from her prior surgery demonstrated the neoplasm originated from her prior endometrioma. Focal areas suggested possible underlying ovarian adenosarcoma with stromal overgrowth.

Discussion:

The incidence of rhabdomyosarcoma arising from endometriosis is exceedingly rare. The accuracy of diagnosing endometriosis and ruling out neoplasm requires coordinated efforts of a multidisciplinary team, involving radiologists, pathologists, oncologists, and gynecologic surgeons.

Magnetic resonance relaxometry improves the accuracy of conventional MRI in the diagnosis of endometriosis-associated ovarian cancer: A case report

Endometriosis is a precancerous condition for endometriosis-associated ovarian cancer (EAOC). In the present study, conventional magnetic resonance imaging (MRI) and MR relaxometry were used to examine a case of clear cell carcinoma that arose in a pre-existing right-sided benign ovarian endometrioma (OE). The 42-year-old nulliparous woman suspected of EOAC, as assessed by conventional MRI, requested fertility-sparing surgery such as laparoscopic endometrioma cystectomy. Furthermore, the MR transverse relaxation rate (R2) was determined using a single-voxel, multi-echo MR sequence using a 3 Tesla-MR system. An R2 value <12.1 s^-1 was indicative of malignancy, as described in previous studies. In the present study, MR relaxometry identified an R2 value of 7.98 s^-1 in the right cyst, which suggested the malignant transformation of benign OE. Based on these findings, fertility-sparing surgery was contraindicated. In conclusion, MR relaxometry may represent a new clinical approach as an adjunctive modality for the diagnosis of EAOC. When patients exhibiting a pelvic mass suspected of EAOC desire fertility-sparing treatment options, MR relaxometry can facilitate the selection of conservative management.

The Sonographic Spectrum of Pelvic Endometriosis: Pearls, Pitfalls, and Mimics

Endometriosis is a common disease of reproductive-age women that is often first encountered with ultrasound. Therefore, familiarity with the variety of manifestations of endometriosis is important for appropriate diagnosis and management. The aim of this article is to review the spectrum of appearance of pelvic endometriosis and to discuss potential mimics on ultrasound. Given that magnetic resonance imaging is an important problem-solving tool in female pelvic imaging, magnetic resonance imaging correlation is also provided.

Intestinal endometriosis: Diagnostic ambiguities and surgical outcomes

BACKGROUND

Endometriosis is a common disease for women of reproductive age. However, when it involves intestines, it is difficult to diagnose preoperatively because its symptoms overlap with other diseases and the results of evaluations can be unspecific. Thus it is important to know the clinical characteristics of intestinal endometriosis and how to exactly diagnose.

AIM

To analyze patients in whom intestinal endometriosis was diagnosed after surgical treatments, and to evaluate the clinical characteristics of preoperatively misdiagnosed cases.

METHODS

We retrospectively reviewed the pathologic reports of 30 patients diagnosed as having intestinal endometriosis based on surgical specimens between January 2000 and December 2017. We reviewed their clinical characteristics and surgical outcomes.

RESULTS

Twenty-three (76.6%) patients showed symptoms associated with endometriosis, with dysmenorrhea being the most common (n = 9, 30.0%). Thirteen patients (43.3%) had a history of pelvic surgeries. Ten patients (33.3%) had a history of treatment for endometriosis. Only 4 patients (13.3%) had a diagnosis of endometriosis based on endoscopic biopsy findings. According to preoperative evaluations, 13 patients (43.3%) had an initial diagnosis of pelvic endometriosis and 17 patients (56.6%) were misdiagnosed as having other diseases. The most common misdiagnosis was submucosal tumor in the large intestine (n = 8, 26.7%), followed by malignancies of the colon/rectum (n = 3, 10.0%) and ovary (n = 3, 10.0%). According to the Clavien-Dindo classification, 5 complications were grade I or II and 2 complications were grade IIIa. The median follow-up period was 26.9 (0.6-132.1) mo, and only 1 patient had a recurrence of endometriosis.

CONCLUSION

Intestinal endometriosis is difficult to diagnose preoperatively because it mimics various intestinal diseases. Thus, if women of reproductive age have ambiguous symptoms and signs with nonspecific radiologic and/or endoscopic findings, intestinal endometriosis should be included in the differential diagnosis.

Deep infiltrating endometriosis MR imaging with surgical correlation

In this pictorial review, MR imaging findings of deep infiltrating endometriosis (DIE) are illustrated together with surgical correlation. DIE can appear as irregular nodules or plaques with similar signal intensity to muscle on both T1-weighted and T2-weighted images. Hemorrhage foci and strands or stellate margins are also often noted. Restriction of diffusion can be seen on diffusion-weighted image. Fibrosis and adhesions often result in morphologic changes, such as alimentary tract tortuosity, irregular or nodular thickening of uterosacral ligaments, and partial or complete obliteration of the pouch of Douglas. After intravenous gadolinium contrast agent administration, homo- or heterogeneous mild to moderate enhancement can be observed. MR imaging can depict endometriosis lesions and extension of DIE at different anatomic locations, which is well consistent with surgical findings. Combining signal and morphological abnormalities, MR imaging can diagnose and assess the extension of DIE with high accuracy. MR imaging findings of DIE facilitate surgeons at treatment decision making and patient communication.

Factors that Differentiate between Endometriosis-associated Ovarian Cancer and Benign Ovarian Endometriosis with Mural Nodules

Purpose:

Mural nodules and papillary projections can be seen in benign ovarian endometriosis (OE) and malignant transformation of OE (endometriosis-associated ovarian cancer [EAOC]), which can pose a challenging diagnostic dilemma to clinicians. We identify the preoperative imaging characteristics helpful to the differential diagnosis between benign OE with mural nodules and EAOC.

Materials and Methods:

This was a retrospective study of 82 patients who were diagnosed pathologically to have OE with mural nodules (n = 42) and malignant transformations of these tumors (n = 40) at the Nara Medical University Hospital from January 2008 to January 2015. All patients were assessed with contrast-enhanced MRI before surgery. Patient demographics, and clinical and pathologic features were analyzed to detect the significant differences between the two groups.

Results:

Histological examinations of resected OE tissue specimens revealed that a majority (78.6%) of the mural nodular lesions were retracted blood clots. We found that the patients with malignant mural nodules, when compared to those with benign nodules, were older, had larger cyst diameters and larger mural nodule sizes, and were more likely to exhibit a taller than wider lesion. They were also more likely to present with various signal intensities on T₁-weighted images (T₁WI), high-signal intensity on T₂-weighted images (T₂WI), a lower proportion of shading on T₂WI, and were more likely to show an anterior location of the cyst. In the multivariate logistic regression analysis, “Height” (>1.5 cm) and “Height-Width ratio (HWR)” (>0.9) of mural nodules, maximum diameter of the cyst (>7.9 cm), and age at diagnosis (>43 years) were independent predictors to distinguish EAOC from OE with mural nodules.

Conclusion:

The “Height” and “HWR” of the mural nodules in the cyst may yield a novel potential diagnostic factor for differentiating EAOC from benign OE with mural nodules.

MR Imaging for Incidental Adnexal Mass Characterization

Incidentally detected adnexal masses are common, and the overwhelming majority of them are benign. As many of these adnexal masses are considered indeterminate at CT or US, a large number of benign oophorectomies occur. Of the malignant adnexal masses, high-grade primary ovarian neoplasms with fast doubling times and early dissemination are the most common. Due to their aggressive behavior, diagnosis of malignancy by interval growth on surveillance imaging represents an undesirable option. Immediate MR characterization allows for a decreased rate of benign oophorectomies and expedited triage of patients to definitive treatment when malignancy is suspected.

Use of enhanced T2 star-weighted angiography (ESWAN) and R2* values to distinguish ovarian cysts due to endometriosis from other causes

PURPOSE

To evaluate the feasibility of enhanced T2 star-weighted angiography (ESWAN) in differentiating endometrial from non-endometrial cysts.

METHODS

Forty-nine patients with 60 histopathologically proven ovarian cystic lesions underwent pelvic MRI including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), liver acquisition with volume acceleration, and ESWAN. Ovarian cystic lesions were divided into endometrial cysts (group 1; n = 28), pyosalpinx and hydrosalpinx (group 2; n = 13), and ovarian cystic and cystic-solid tumors (group 3; n = 19). R2* (effective transverse relaxation rate) values were measured and pairwise comparison of the R2* values among the three groups was made using Kruskal-Wallis test. Receiver operating characteristic curves were used to calculate cutoff values and performance of R2* values for distinguishing among groups. T1WI signal intensity and R2* value were also compared using area under curve values.

RESULTS

R2* values for group 1 were statistically higher than groups 2 and 3 (15.37, 1.40, and 1.79 Hz, respectively; P < 0.001). The cutoff value for R2* was 7.43 Hz with a sensitivity, specificity, PPV, NPV, and accuracy of 96.43, 87.50, 87.10, 96.55, and 91.67%, respectively. There was no significant difference between the R2* value and T1WI in diagnosing endometrial cysts.

CONCLUSIONS

The R2* value provides an effective way to discriminate endometrial cysts from other ovarian cystic lesions.

The utility of ultrasound elastography in differentiation of endometriomas and hemorrhagic ovarian cysts

PURPOSE

To investigate the feasibility of acoustic radiation force impulse imaging in differentiation of endometriomas and hemorrhagic ovarian cysts.

MATERIALS AND METHODS

We evaluated 84 ovarian cysts with high internal echogenicity diagnosed in 70 consecutive women. We excluded simple cysts and hemorrhagic cysts containing septations or mural nodules with detectable flow on Doppler ultrasonography. We obtained the elastographic shear wave velocity (SWV) value of the cysts that could be endometriomas or hemorrhagic ovarian cysts.

RESULTS

Among the 78 ovarian cysts in 70 women without any septation or mural nodule, there were 42 endometriomas and 36 hemorrhagic ovarian cysts. Analysis of median SWV values of the ovarian cysts showed that the endometriomas had considerably higher levels of stiffness compared to the hemorrhagic ovarian cysts [median SWV 4.20 ± 0.42 vs 2.54 ± 1.04 m/s, p < 0.001]. A SWV cutoff value greater than 3.81 m/s yielded sensitivity and specificity values of 82.1 and 79.2 % respectively, for differentiation of endometriomas from hemorrhagic ovarian cysts.

CONCLUSION

Sonoelastography is a novel imaging technique that enables us to evaluate the stiffness of adnexal lesions. The accurate discrimination of endometriomas and hemorrhagic ovarian cysts is important for avoiding unnecessary surgical procedures. ARFI imaging has a high sensitivity and specificity for distinguishing endometrioma from hemorrhagic ovarian cysts.

New insights in the pathophysiology of ovarian cancer and implications for screening and prevention

Despite advances in medicine, ovarian cancer remains the deadliest of the gynecological malignancies. Herein we present the latest information on the pathophysiology of ovarian cancer and its significance for ovarian cancer screening and prevention. A new paradigm for ovarian cancer pathogenesis presupposes 2 distinct types of ovarian epithelial carcinoma with distinct molecular profiles: type I and type II carcinomas. Type I tumors include endometrioid, clear-cell carcinoma, and low-grade serous carcinoma and mostly arise via defined sequence either from endometriosis or from borderline serous tumors, mostly presenting in an early stage. More frequent type II carcinomas are usually high-grade serous tumors, and recent evidence suggests that the majority arise from the fimbriated end of the fallopian tube. Subsequently, high-grade serous carcinomas usually present at advanced stages, likely as a consequence of the rapid peritoneal seeding from the open ends of the fallopian tubes. On the other hand, careful clinical evaluation should be performed along with risk stratification and targeted treatment of women with premalignant conditions leading to type I cancers, most notably endometriosis and endometriomas. Although the chance of malignant transformation is low, an understanding of this link offers a possibility of prevention and early intervention. This new evidence explains difficulties in ovarian cancer screening and helps in forming new recommendations for ovarian cancer risk evaluation and prophylactic treatments.

Primary ovarian endometrioid adenocarcinoma: magnetic resonance imaging findings including a preliminary observation on diffusion-weighted imaging

OBJECTIVE

This study aimed to investigate the magnetic resonance imaging (MRI) features of ovarian endometrioid adenocarcinoma (OEC) and to evaluate conventional MRI and diffusion-weighted imaging (DWI) for diagnosing OEC.

MATERIALS AND METHODS

Twenty patients with OEC proven by surgery and pathology underwent MRI. The MRI features of the tumors evaluated included laterality, shape, size, configuration, mural nodules, signal intensity, apparent diffusion coefficient (ADC) values, enhancement, peritoneal implants, ascites, and synchronous primary cancer (SPC) of the ovary and endometrium.

RESULTS

Unilateral ovarian masses were observed in 18 (90%) of the 20 patients with 22 OEC lesions, whereas the remaining 2 (10%) patients had bilateral masses. Oval, lobulated, and irregular shapes were observed in 13 (59%), 6 (27%), and 3 (14%) tumors, respectively. The maximum diameter of the tumors ranged from 3.7 to 22.5 cm, with a mean of 11.2 ± 5.1 cm. Fifteen (68%) masses were mainly cystic with mural nodules, 5 (23%) were mixed cystic-solid, and 2 (9%) were solid. The solid components of tumors showed isointensity (100%) on T1-weighted imaging (T1WI), heterogeneous hyperintensity on T2-weighted imaging (T2WI) (86%), and hyperintensity on DWI (82%), with a mean ADC value of (0.96 ± 0.20) × 10 mm/s. The cystic components showed isointensity or hyperintensity (85%) on T1WI, hyperintensity on T2WI (100%), and hypointensity on DWI (63%), with a mean ADC value of (2.27 ± 0.27) × 10 mm/s. Ten (50%) of the patients were SPC. The mean ADC values of the solid components were (0.85 ± 0.19) × 10 mm/s and (1.08 ± 0.15) × 10 mm/s in only-OEC and SPC, respectively, with a statistically significant difference (P = 0.012).

CONCLUSIONS

Ovarian endometrioid adenocarcinoma usually appears as a large, oval, or lobulated cystic mass with mural nodules. Cystic components show isointensity or hyperintensity on T1WI, solid components and hyperintensity on T2WI and DWI. Synchronous primary cancer of the ovary endometrium is another characteristic feature of OEC.

Malignant Transformation of Pelvic Endometriosis: Case Series and Review of the Literature

Endometriosis affects 4% to 13% of all women of reproductive age although its true incidence is unknown. The ability of endometriosis to transform into malignancy, first described by Sampson in 1925, is a rare occurrence affecting 1% of lesions with ovary being the primary site in 79%. The authors describe 3 premenopausal women without risk factors for malignancy presenting with ovarian and/or extraovarian endometrioid adenocarcinoma. All of them demonstrated features of pre-/coexisting endometriosis but malignancy was preoperatively suspected in only 1 instance. Postsurgical follow-up of the cases did not document any recurrence. The propensity for malignant conversion occurring in women 10 to 20 years younger vis-a-vis those affected by de novo ovarian cancer, destruction of the endometriotic foci, and underreporting vindicate close follow-up and scrutiny of women with endometriosis and ovarian endometriomas.

Complex abdominopelvic endometriosis: the radiologist's perspective

Endometriosis is a multifocal gynecological disorder affecting approximately 6%-10% of women during their reproductive years (Giudice and Kao in: Lancet 364:1789-1799, 2004). Presenting symptomatology often relates to the anatomical structures involved. Given the complexity of both the management and pain control of patients with complex endometriosis, the British Society of Gynaecological Endoscopy has issued guidelines on the establishment of a multidisciplinary team approach to these cases (http://www.bsge.org.uk/ec-requirements-BSGE-accredited-endometriosis-centre.php). The ovaries are the most common site affected, but the gastrointestinal, genitourinary tract, chest and other soft tissues are not infrequently involved. Less well-recognized features of the disease include the deep infiltrative form of endometriosis, malignant transformation and decidualization of endometriomas under progesterone. In this pictorial essay, we will discuss the clinical presentation and review the imaging features of these complex and under appreciated forms of endometriotic disease.

Lesions of the ovary with T1-hypersignal

Pelvic magnetic resonance imaging (MRI) has been used successfully to diagnose ovarian masses that cannot be adequately evaluated using pelvic ultrasound. T1 hyperintensity is a common finding in an ovarian mass and has important diagnostic implications. The aims of this review are to list the substances that may produce high signal intensity on T1-weighted MRI, to explain the physical basis for causes of the high T1 signal intensity, and to describe common and uncommon T1 hyperintense ovarian lesions. The morphological findings, the imaging features of the additional sequences, and clinical variables can help in the differential diagnosis, and in some cases, enable a specific diagnosis, leading to appropriate management of the patient.

Management of pregnancy in woman with suspected malignant deep infiltrating endometriosis fistulised to the uterine cervix

Deep infiltrating endometriosis (DIE) is a well-known cause of pelvic pain and infertility. Malignant transformation of DIE is rare but can be suggested by MRI. We report a case of a spontaneous pregnancy in a woman with suspicion of malignant transformation of DIE with fistulisation to the posterior uterine isthmus through to the cervical canal. The pregnancy was closely monitored and an uneventful caesarian section was performed at 34 weeks of gestation. This case raises the issue of the relevance of imaging techniques and management of pregnancy.

Detection and differential diagnosis of suspected malignant transformation of an endometrioma during pregnancy

Asymptomatic female in her early 30s presented for her singleton nuchal translucency ultrasound at 12.4 weeks of gestational age. No fetal abnormalities were seen. A large maternal left adnexal mass was identified, prompting a transvaginal ultrasound. The findings were felt to be consistent with an endometrioma, albeit with a 1 cm solid nodule. At this point, the diagnosis was considered to likely represent a decidualised endometrioma; however, warranting careful follow-up. The 20-week anatomy scan demonstrated an enlarging solid nodule that now contained vascularity within the left adnexal mass prompting an MRI. These features were more suggestive of malignancy, although a decidualised endometrioma, which can demonstrate intrapartum growth and vascularity, remained in the differential. Intrapartum sonographic surveillance documented progressive growth. The lesion was uneventfully removed at the time of delivery. Pathology showed clear cell carcinoma within an endometrioma.

Malignant transformation of endometriosis within the urinary bladder

Although endometriosis of the pelvic organs is common, endometriosis of the urinary bladder is extremely rare. Malignant transformation of atypical endometriotic foci is an uncommon but well-documented sequela, occurring in approximately 1% of cases. This article reports the fourth case in the English literature of clear cell carcinoma arising from foci of endometriosis within the posterior bladder wall.