Different staining patterns of ovarian Brenner tumor and the associated mucinous tumor

Malignant Brenner Tumor of the Ovary: A Critical Reappraisal

Malignant Brenner tumors (MBTs) are rare epithelial tumors of the ovary, most likely arising from benign and borderline Brenner tumors. MBTs may be misdiagnosed as other primary carcinomas or nonepithelial tumors of the ovary as well as metastatic carcinomas. Accurate diagnosis usually requires clinical-radiologic correlation, extensive sampling, and immunohistochemical studies. Treatment is not standardized and may include surgery with or without chemotherapy. More than half of MBTs are diagnosed at stage I, with 47.7% and at least 20% recurrence and mortality rates, respectively. Awareness of key diagnostic features and pitfalls is essential to differentiate MBT from its mimics and ensure optimal clinical management. This comprehensive review includes classification, etiopathogenesis, historical overview, epidemiology, clinical features, treatment, prognosis, gross pathology, key morphologic features, ancillary testing, and differential diagnostic considerations for ovarian MBTs.

Management of a Borderline Brenner Tumor of the Ovary in a Premenopausal Woman in Northern Tanzania. A Rare Case Report and Review of the Current Literature

Brenner tumors are rare ovarian neoplasms that are typically small and unilateral. Most cases are benign; less than 5% of all Brenner tumors are borderline or proliferative. Brenner tumors originate from the follicular epithelium and consist of ovarian transitional cells surrounded by fibrous tissue. Here we present a case of a 49-year-old premenopausal woman from Northern Tanzania. This patient presented to our facility with acute abdominal pain. She also reported abdominal distention which was first noticed 12 months prior to presentation. Magnetic resonance imaging (MRI) identified a 21 × 17 × 5 cm complex cyst with a thickened wall on the right ovary. The radiological findings were suggestive of an ovarian cystadenoma; multiple intramural and subserosal uterine leiomyomas were also noted. A total abdominal hysterectomy (TAH) and bilateral salpingo-oophorectomy (BSO) was performed. Histopathological findings identified an atypical proliferative borderline Brenner tumor of the right ovary. Postoperative recovery was uneventful, the patient was discharged and managed conservatively postoperatively.

Benign Brenner tumor of the ovary: two-dimensional and contrast-enhanced ultrasound features-a retrospective study from a single center

Objective

Benign Brenner tumor (BBT) is a rare ovarian tumor, and there are few discrete reports about its manifestation in an ultrasound. This study sought to investigate the two-dimensional (2D) and contrast-enhanced ultrasound (CEUS) features of this entity.

Methods

This is a retrospective single-center study. The clinical manifestations, laboratory examination, and ultrasound data of 25 female patients with BBT were confirmed by pathology when they underwent 2D and/or CEUS examination at Ningbo First Hospital from January 2012 to June 2023. The ultrasound findings of the patients were analyzed using the terminology of the International Organization for the Analysis of Ovarian Tumor and were read by two senior sonographers who reached an agreement.

Results

Among the all 25 patients, most of them were unilateral, and only one patient was bilateral. Thus, 26 lesions were found: 44.0% (11/25) were in the left and 52.0% (13/25) were in the right. Moreover, 53.84% (14/26) were solid lesions, 15.38% (4/26) were mixed lesions, and 26.92% (7/26) were cystic lesions. Among the solid-type patients, 42.85% (6/14) of the cases were with calcification. Upon laboratory examination, 12.0% (3/25) of the patients had high carbohydrate antigen 125 (CA-125) level, and 19.04% (4/21) of the patients had an elevated carbohydrate antigen724 (CA-724) level in the serum tumor markers. In the hormone test, 14.28% (3/21) were found to have a high postmenopausal estrogen level and 14.28%(3/21) were found to have a high level of follicle-stimulating hormone (FSH). One patient with complex manifestations and three with solid manifestations were examined by CEUS to observe the microcirculation perfusion of the tumor. One with solid and cystic separation was rapidly hyperenhanced and cleared, and the filling subsided faster than the uterus. The postoperative pathological diagnosis was benign Brenner tumor with mucinous cystadenoma. The other three cases were solid adnexal lesions, which showed isoenhancement on CEUS and disappeared slowly, synchronizing with the uterus. The CEUS results were considered as benign tumors and confirmed by pathology.

Conclusions

BBT can show ovarian cystic, mixed cystic and solid type, and solid echo in 2D ultrasound. Unilateral ovarian fibrosis with punctate calcification is an important feature of BBT in 2D ultrasound. However, for solid adnexal masses and mixed cystic and solid masses with unclear diagnosis, if CEUS shows isoenhancement or hyperenhancement, the possibility of BBT cannot be excluded.

Synergy of the microRNA Ratio as a Promising Diagnosis Biomarker for Mucinous Borderline and Malignant Ovarian Tumors

Epithelial ovarian cancers (EOCs) are a heterogeneous collection of malignancies, each with their own developmental origin, clinical behavior and molecular profile. With less than 5% of EOC cases, mucinous ovarian carcinoma is a rare form with a poor prognosis and a 5-year survival of 11% for advanced stages (III/IV). At the early stages, these malignant forms are clinically difficult to distinguish from borderline (15%) and benign (80%) forms with a better prognosis due to the large size and heterogeneity of mucinous tumors. Improving their diagnosis is therefore a challenge with regard to the risk of under-treating a malignant form or of unnecessarily undertaking radical surgical excision. The involvement of microRNAs (miRNAs) in tumor progression and their potential as biomarkers of diagnosis are becoming increasingly recognized. In this study, the comparison of miRNA microarray expression profiles between malignant and borderline tumor FFPE samples identified 10 down-regulated and 5 up-regulated malignant miRNAs, which were validated by individual RT-qPCR. To overcome normalization issues and to improve the accuracy of the results, a ratio analysis combining paired up-regulated and down-regulated miRNAs was performed. Although 21/50 miRNA expression ratios were significantly different between malignant and borderline tumor samples, any ratio could perfectly discriminate the two groups. However, a combination of 14 pairs of miRNA ratios (double ratio) showed high discriminatory potential, with 100% of accuracy in distinguishing malignant and borderline ovarian tumors, which suggests that miRNAs may hold significant clinical potential as a diagnostic tool. In summary, these ratio miRNA-based signatures may help to improve the precision of histological diagnosis, likely to provide a preoperative diagnosis in order to adapt surgical procedures.

Borderline Brenner tumor of the ovary with mucinous metaplasia: A case report

Key Clinical Message

To date, there have been disparate reports regarding borderline forms of Brenner tumors, while research on concomitant mucinous proliferation is even more irregular; however, it has been observed that proper diagnosis and treatment have proven to have a favorable prognosis on the aforementioned tumor.

Abstract

Brenner tumor is a rare epithelial ovarian neoplasm responsible for 2%-3% of all ovarian tumors. These tumors are usually asymptomatic and can usually be found incidentally in pathological studies. They can also manifest themselves as abdominal pain or abnormal uterine bleeding. A 41-year-old female with a history of anemia referred to the hospital suffering from abdominal pain for at least 1 month before the referral period. Physical examination revealed a mobile palpable mass in the left lower abdomen. Ultrasound and pelvic computed tomography scan (CT scan) revealed a left ovarian complex cyst. Left salpingo-oophorectomy was performed on the patient, and the cyst was removed. Pathological findings revealed an atypical proliferative Brenner tumor with mucinous metaplasia. To date, there have been disparate reports regarding borderline forms of Brenner tumors, while research on concomitant mucinous proliferation is even more irregular; however, it has been observed that proper diagnosis and treatment have proven to have a favorable prognosis on the aforementioned tumor.

Comparison of performance between O-RADS, IOTA simple rules risk assessment and ADNEX model in the discrimination of ovarian Brenner tumors

PURPOSE

To describe the clinical and sonographic features of ovarian benign Brenner tumor (BBT) and malignant Brenner tumor (MBT), and to compare performance of four diagnostic models in differentiating them.

METHODS

Fifteen patients with BBTs and nine patients with MBTs were retrospectively identified in our institution from January 2003 and December 2021. One ultrasound examiner categorized each mass according to ovarian-adnexal reporting and data system (O-RADS), international ovarian tumor analysis (IOTA) Simple Rules Risk (SR-Risk) assessment and assessment of different neoplasias in the adnexa (ADNEX) models with/without CA125. Receiver operating characteristic curves were generated to compare diagnostic performance.

RESULTS

Patients with MBT had higher CA125 serum level (62.5% vs. 6.7%, P = 0.009) and larger maximum diameter of lesion (89 mm vs. 43 mm, P = 0.009) than did those with BBT. BBT tended to have higher prevalence of calcifications (100% vs. 55.6%, P = 0.012) and acoustic shadowing (93.3% vs. 33.3%, P = 0.004), and lower color scores manifesting none or minimal flow (100.0% vs. 22.2%, P < 0.001). Areas under curves of O-RADS, IOTA SR-Risk and ADNEX models with/without CA125 were 0.896, 0.913, 0.892 and 0.896, respectively. There were no significant differences between them.

CONCLUSION

BBTs are often small solid tumors with sparse color Doppler signals, which contain calcifications with posterior acoustic shadowing. The most common pattern of MBT is a large multilocular-solid or solid mass with irregular tumor borders, and most were moderately or richly vascularized at color Doppler. These four models have excellent performance in distinguishing them.

Brenner Tumor of the Ovary: A 10-Year Single Institution Experience and Comprehensive Review of the Literature

Brenner tumors (BTs) are surface-epithelial stromal cell tumors that are categorized by the World Health Organization as benign, borderline, and malignant. Due to the rarity of BTs, the published literature on these tumors is comprised primarily of case reports and small retrospective studies. We performed a pathology database review spanning the last ten years at our institution revealing nine reported benign BTs. We collected the clinical and pathological data of patients associated with those BTs, describing the clinical presentation and imaging results, and assessing the possible risk factors associated with them. The average age at diagnosis was 58 years. BTs were discovered incidentally in 7/9 cases. The tumor was multifocal and bilateral in 1/9 cases and ranged in size from 0.2 cm to 7.5 cm. Associated Walthard rests were found in 6/9 cases and transitional metaplasia of surface ovarian and/or tubal epithelium was found in 4/9 cases. One patient had an associated mucinous cystadenoma in the ipsilateral ovary. Another patient had an associated mucinous cystadenoma in the contralateral ovary. In conclusion, we found that Walthard rests and transitional metaplasia are common findings in association with BTs. Additionally, pathologists and surgeons need to be aware of the association between mucinous cystadenomas and BTs.

Mucinous Borderline Tumor Associated with Mesonephric-like Proliferation: Further Evidence for a Possible New Origin of Ovarian Mucinous Neoplasms

Some ovarian mucinous tumors are thought to originate from Brenner tumors and teratomas; however, data are limited on what could be the origin for the remaining tumors. We report a new case of ovarian mucinous borderline tumor/atypical proliferative mucinous tumor (MBT/APMT) co-existing with a mesonephric-like proliferation (MLP)/mesonephric-like hyperplasia (MLH). The patient was a 58-year-old woman who presented with a pelvic mass and abdominal pain. Pathology demonstrated an 11 cm MBT/APMT in the left ovary. In addition, the tumor contained one focal area (<1% of total tumor volume) of MLP/hyperplasia adjacent to, or intimately admixed with, mucinous epithelium, with an immunophenotype of diffuse Pax8 and Gata3 expression and negative TTF-1, ER, and PR staining. Pax8 was also weakly positive in the MBT/APMT component. Some mesonephric-like glands partially exhibited gastrointestinal-type mucinous metaplasia/differentiation. A polymerase chain reaction (PCR)-based Sanger sequencing demonstrated that a KRAS G12V mutation was present in both MLP/MLH and MBT/APMT components, providing further evidence to support their clonal relationship. We previously reported a series of similar cases and demonstrated a novel association between MLP, mesonephric-like adenocarcinoma and ovarian mucinous tumor. It is conceivable that benign MLPs may have ability to differentiate to lineage-specific mucinous lesions, and, as such, they may serve as a possible new origin of some ovarian mucinous neoplasms; in particular, Pax8-positive tumors. The current case provides additional evidence to support this theory.

Coexistence of malignant ovarian Brenner tumor and borderline mucinous cystadenoma, combined with primary uterine corpus endometrioid carcinoma: A case report and literature review

Malignant Brenner tumor (MBT) of the ovary is a rare malignant ovarian tumor, whereas uterine corpus endometrioid carcinoma (UEC) constitutes one of the most common malignant tumors of the female reproductive system. The present study reported on a case of the coexistence of ovarian MBT and borderline mucinous cystadenoma combined with primary UEC. Therefore, the present case is a synchronous primary cancer of both ovary and endometrium. Although synchronous primary cancers of the endometrium and ovary are relatively uncommon, they are not rare; however, due to the rarity of MBT, this case was considered singular. To the best of our knowledge, this was the first-ever reported case of the coexistence of an ovarian MBT and borderline mucinous cystadenoma combined with primary UEC. Based on a review of the literature associated with the present case, its clinicopathological features, immunohistochemical phenotype, differential diagnosis, molecular changes, prognosis and treatment were summarized and discussed. The aim of the present study was to improve the understanding of this rare synchronous primary cancer of the ovary and endometrium so as to avoid future misdiagnosis.

Brenner tumors of the ovary: Clinical features and outcomes in a single-center cohort

Objective:

The purpose of the present study was to evaluate the clinical and pathological features and oncological outcomes of Brenner tumors (BT).

Material and Methods:

Evaluation was performed on the data of 46 patients with BTs retrieved from the oncology clinic database and pathology reports between 2005 and 2020.

Results:

The median (range) age of the patients was 52 (22-75) years. Median (range) tumor size was 52.5 (5.0-300) mm. The tumor was benign in 37 (80.4%), borderline in one (2.2%), and malignant in the remaining eight (17.4%). Ten (21.7%) of the tumors were detected incidentally. Mixed tumor, BT plus another ovarian pathology, was found in 13 (28.2%). Recurrence developed in 2/8 (25%) with malignant BT (MBT). The stage of these patients was 3C, and both received chemotherapy after surgery.

Conclusion:

BTs are rare and generally detected incidentally. MBTs are treated in the same way as epithelial tumors. Due to the rarity of these tumors, lymphadenectomy and optimal chemotherapy regimens are controversial issues.

MDM2 amplification in malignant Brenner tumors may play a role in progression to malignancy and aid in separation from urothelial and other ovarian carcinomas

Malignant Brenner tumor (MBT) is diagnosed in the setting of invasive high-grade carcinoma with urothelial-like morphology and the presence of an adjacent benign Brenner tumor (BBT) or borderline Brenner tumor (BLBT). MDM2 amplification was recently detected by next-generation sequencing on a small number of MBTs, potentially significant for future targeted therapy. Experience is limited, however, and evaluation of widely available MDM2 immunohistochemistry (IHC) has not been performed to determine clinical utility. After confirming all diagnoses morphologically and immunohistochemically, we performed MDM2 IHC on 4 MBTs, 3 BLBTs, 26 BBTs, 142 high-grade serous carcinomas (HGSC), 6 ovarian endometrioid carcinomas (OEC) with urothelial-like morphology, and 49 high-grade urothelial carcinomas (HGUC). MDM2 IHC was considered positive with diffuse (>25%) nuclear reactivity; in cases of patchy staining (10-25% nuclear reactivity), MDM2 was considered equivocal. Positive staining in <10% of cells was considered negative. In cases with positive or equivocal staining, MDM2 amplification was evaluated by fluorescence in-situ hybridization (FISH). Three MBTs (75%) showed diffuse nuclear reactivity for MDM2 by IHC, a finding corroborated by amplification of MDM2 in all three cases. One MBT and 2 BLBTs showed equivocal MDM2 IHC, but all three were negative for MDM2 amplification. The final BLBT, as well as all BBTs, HGSC, OEC, and HGUC, were negative for MDM2. In conclusion, our limited cohort confirms MDM2 amplification in MBT and suggests that MDM2 IHC may have an influence in rare diagnostically challenging cases.

Benign Brenner tumour of the ovary: CT and MRI features

AIM

To evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) features of benign Brenner tumours (BBT) of the ovary.

MATERIAL AND METHODS

This was a retrospective two-centre study comprising 35 female patients with a definitive diagnosis of BBT at histology in whom CT and/or MRI examinations had been performed. Two experienced radiologists reviewed the CT and MRI features of 39 ovarian BBT retrospectively with consensus reading. The morphological appearance and size of each tumour were recorded. The presence or absence of calcifications within the solid portion was noted at CT. The reviewed characteristics at MRI included qualitative assessment of the signal intensity of the solid portion on diffusion sequence and contrast enhancement, compared to that of the myometrium.

RESULTS

CT and MRI images were available for 27 and 28 lesions, respectively. Sixteen patients had both CT and MRI examinations. BBT were unilateral in 89% of patients, and 49% of lesions were solid and 51% were mixed. Calcifications were depicted at CT in 70.4% of lesions. When present, the cystic portion was multilocular in 85% of cases and corresponded to a mucinous lesion in 74% of cases. Enhancement of the solid portion at MRI was inferior or equal to that of the myometrium in 89% of cases and signal on high b-values diffusion images was deemed low or moderate in 93% of cases.

CONCLUSION

The combined CT and MRI findings of a unilateral fibrous ovarian mass containing punctate calcifications often associated with a multilocular cyst suggest the diagnosis of ovarian BBT.

Brenner tumor associated with rete ovarii: a histologic and immunohistochemical analysis of six cases exploring the relationship between these entities

The association of Brenner tumor (BT) with rete ovarii (RO) has been rarely alluded to in the literature. Both entities have debatable histogenesis. In this study of six cases of BT associated with RO, we describe the morphologic features and performed immunohistochemical staining for markers of Mullerian, Wolffian, mesothelial, and sex cord stromal derivation to explore the relationship between these entities. Histologically, all BTs were benign, microscopic, and incidental. RO was prominent and hyperplastic with gradual or abrupt transition to BT. In addition, focal areas of rete entrapped between BT nests were seen. All BTs were positive for GATA-3 and negative for PAX-8. Conversely, the RO in all cases was negative for GATA-3 and positive for PAX-8. WT-1 was positive in both entities. Sex cord stromal and mesothelial markers (other than WT-1) were negative in BT and RO. Although morphologically, BTs seem to arise from RO in these cases, they have a distinct immunophenotype. It is possible that at least some BTs arise from metaplastic changes in RO epithelium.

Amplification of MDM2 and Loss of p16 Expression: Do They Have a Role in Malignant Transformation of Ovarian Brenner Tumor?

OBJECTIVES

To review the significance of MDM2 and cyclin D1 expression and loss of p16 expression in malignant and borderline Brenner tumors (BTs) of the ovary.

METHODS

We describe 2 new cases of ovarian BT, 1 malignant and 1 borderline. We studied MDM2, p16, and cyclin D1 expression by immunohistochemistry in the benign, borderline, and malignant components of these 2 cases and in 5 additional cases of benign BT. We also reviewed and summarized the literature on the clinical, immunohistochemical and molecular characteristics of borderline and malignant BTs (BdBTs and MBTs).

RESULTS

Nuclear expression of MDM2 was seen only in the MBT. Loss of p16 expression was seen in both BdBT and MBT. Cyclin D1 expression was in proportion to the degree of malignancy. Amplification of MDM2, loss of CDKN2A (p16-encoding gene), and amplification of CCND1 (cyclin D1-encoding gene) were confirmed by commercial next-generation sequencing in the case of MBT.

CONCLUSIONS

We are the first to report immunohistochemical expression of MDM2 in an MBT. Amplification of MDM2 and loss of p16 expression may have a role in malignant transformation of BT.

Two types of primary mucinous ovarian tumors can be distinguished based on their origin

The origin of primary mucinous ovarian tumors is unknown. We explore the hypothesis that they originate from either Brenner tumors or teratomas and examine differences between the tumors that arise in these settings. A total of 104 Brenner tumor-associated mucinous tumors and 58 teratoma-associated mucinous tumors were analyzed. Immunohistochemistry for 21 antigens and fluorescence in situ hybridization for ERBB2 and MYC were performed. Genome-wide copy number analysis and mutation analysis for 56 cancer-related genes was carried out on a subset of mucinous ovarian tumors and their complementary Brenner tumor or teratoma. Patients with teratoma-associated mucinous tumors were significantly younger than patients with Brenner tumor-associated mucinous tumors (43 vs. 61 years). During progression from cystadenoma to atypical proliferative mucinous (borderline) tumor to carcinoma expression of typical gastrointestinal markers was increased in both Brenner tumor-associated and teratoma-associated mucinous tumors. Brenner tumor-associated mucinous tumors showed more frequently calcifications and Walthard cell nests, rarely expressed SATB2 and showed more often co-deletion of CDKN2A and MTAP. Teratoma-associated mucinous tumors were characterized by mucinous stromal dissection, SATB2 expression and RNF43 mutations. Other frequent mutations in both Brenner tumor-associated and teratoma-associated mucinous tumors were TP53 and KRAS mutations. Based on identical mutations or copy number profiles clonal relationships were indicated in two mucinous tumors and their associated Brenner tumor. Teratomas and Brenner tumors give rise to different subtypes of mucinous ovarian tumors. Subsequent progression pathways are comparable since both Brenner tumor-associated and teratoma-associated mucinous tumors develop a gastrointestinal immunophenotype during progression and show early mutations in KRAS and TP53. Teratoma-associated mucinous tumors may more closely resemble true gastrointestinal tumors, indicated by their expression of SATB2 and the presence of RNF43 mutations.

Borderline Brenner Tumor: A Review of the Literature

Brenner tumors arise from ovarian epithelium, accounting for approximately 5% of benign ovarian epithelial tumors. The World Health Organization classification groups them into benign, borderline, and malignant on the basis of proliferation and invasiveness, and borderline Brenner tumor is defined as “displaying epithelial proliferation beyond that seen in benign Brenner's tumor, but lacking stromal invasion.” Borderline Brenner tumors are rare. Fewer than 60 cases have been reported. The more recent articles mostly focus on pathogenesis. We reviewed the literature on borderline Brenner tumor and have summarized the clinical and pathologic findings, as well as the treatment, differential diagnoses, and recent advances in histogenesis and molecular pathogenesis.

Ovarian mucinous cystic tumor associated with sarcomatous mural nodule and benign Brenner tumor: A case report and literature review

RATIONALE

Ovarian mucinous tumor with malignant mural nodule is exceedingly rare. We report a case of ovarian mucinous cystic tumor associated with sarcomatous mural nodule and benign Brenner tumor and accompanied by nodular histiocytic aggregates in the greater omentum.

PATIENT CONCERNS

A 60-year-old postmenopausal woman was presented with a history of one month of lower abdominal discomfort, abdominal distension, nausea, and vomiting. A physical examination revealed a hard, palpable mass with mild tenderness in her right lower abdomen.

DIAGNOSES

The mucinous tumor was solid and cystic and contained benign, borderline, and malignant elements. Within the solid areas, two nodules representing pleomorphic undifferentiated sarcoma and benign Brenner tumor were identified. The diagnosis of malignant mural nodule was based on vascular invasion and marked nuclear atypia, including atypical mitoses and mitotic activity.

INTERVENTIONS

Bilateral salpingo-oophorectomy and partial omentectomy were performed. Malignant cells were not found on cytologic examination of the peritoneal washing fluid. The patient underwent three cycles of chemotherapy with 210 mg paclitaxel liposome via an intravenous drip, 20 mg nedaplatin via an intravenous drip, and 80 mg nedaplatin via intraperitoneal perfusion.

OUTCOMES

The patient has been followed up for 3 years without evidence of tumor recurrence and metastasis.

LESSONS

Careful classification of a mural nodule is important to triage patients in need of aggressive adjuvant treatment.

[Grading of gynecological tumors : Current aspects]

Histopathological assessment of the tumor grade and cell type is central to the management and prognosis of various gynecological malignancies. Conventional grading systems for squamous carcinomas and adenocarcinomas of the vulva, vagina and cervix are poorly defined. For endometrioid tumors of the female genital tract as well as for mucinous endometrial, ovarian and seromucinous ovarian carcinomas, the 3‑tiered FIGO grading system is recommended. For uterine neuroendocrine tumors the grading system of the gastrointestinal counterparts has been adopted. Uterine leiomyosarcomas are not graded. Endometrial stromal sarcomas are divided into low and high grades, based on cellular morphology, immunohistochemical and molecular findings. A chemotherapy response score was established for chemotherapeutically treated high-grade serous pelvic cancer. For non-epithelial ovarian malignancies, only Sertoli-Leydig cell tumors and immature teratomas are graded. At this time molecular profiling has no impact on the grading of tumors of the female genital tract.

Malignant Brenner tumor of the ovary: Review and case report

Ovarian neoplasms are a heterogeneous group of tumors with varying incidence in the general population. The most common are the surface epithelial tumors which include transitional cell tumors. Transitional cell tumors include both transitional cell carcinoma and Brenner tumor. The vast majority of Brenner tumors are benign, often incidental findings; however, malignant Brenner tumors (MBT) do occasionally occur. MBT present similarly to other ovarian neoplasms with abdominal pain and bulk symptoms. On imaging, these tumors demonstrate nonspecific findings. Microscopically, they demonstrate areas of conventional benign Brenner tumor juxtaposed with regions of frank malignancy showing marked cytologic atypia and infiltration. There is no consistent tumor marker for these tumors, but CA-125, CA 72-4 and SCC have been reported in singular instances. Tumors express several immunohistochemical markers of urothelial differentiation including uroplakin III, thrombomodulin, GATA3, p63, as well as cytokeratin 7. The primary treatment modality is surgical excision. Due to their rarity, the precise role and regimen of adjuvant chemo-radiation therapy for MBT has not been established. We herein review a case of MBT with emphasis on primary treatment and treatment of recurrent disease, including the use of adjuvant pelvic radiation, discuss the current state of the literature and standards of practice regarding this malignancy.

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Histologic differentiation of MBT from TCC is critical for diagnosis.

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Surgical staging should be performed for all cases of MBT.

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The role of adjuvant strategies for MBT is poorly defined.

Molecular Genetic Analysis of Ovarian Brenner Tumors and Associated Mucinous Epithelial Neoplasms: High Variant Concordance and Identification of Mutually Exclusive RAS Driver Mutations and MYC Amplification

Benign ovarian Brenner tumors often are associated with mucinous cystic neoplasms, which are hypothesized to share a histogenic origin and progression, however, supporting molecular characterization is limited. Our goal was to identify molecular mechanisms linking these tumors. DNA from six Brenner tumors with paired mucinous tumors, two Brenner tumors not associated with a mucinous neoplasm, and two atypical proliferative (borderline) Brenner tumors was extracted from formalin-fixed, paraffin-embedded tumor samples and sequenced using a 358-gene next-generation sequencing assay. Variant calls were compared within tumor groups to assess somatic mutation profiles. There was high concordance of the variants between paired samples (40% to 75%; P < 0.0001). Four of the six tumor pairs showed KRAS hotspot driver mutations specifically in the mucinous tumor. In the two paired samples that lacked KRAS mutations, MYC amplification was detected in both of the mucinous and the Brenner components; MYC amplification also was detected in a third Brenner tumor. Five of the Brenner tumors had no reportable potential driver alterations. The two atypical proliferative (borderline) Brenner tumors both had RAS mutations. The high degree of coordinate variants between paired Brenner and mucinous tumors supports a shared origin or progression. Differences observed in affected genes and pathways, particularly involving RAS and MYC, may point to molecular drivers of a divergent phenotype and progression of these tumors.

Clonality analysis of combined Brenner and mucinous tumours of the ovary reveals their monoclonal origin

The derivation of ovarian intestinal-type mucinous tumours is not well established. Some are derived from teratomas but the origin of the majority is not clear. It has been recently proposed that the non-germ cell group may be derived from Brenner tumours, as the association of a mucinous tumour with a Brenner tumour is frequently observed. In order to explore the histogenesis of these neoplasms, we undertook a clonality analysis of the two components of ten combined Brenner and mucinous tumours using a human androgen receptor gene (HUMARA) assay. All eight informative cases of ten showed a concordant X-chromosome inactivation pattern between the two tumour components, indicative of a shared clonal origin (p = 0.0039). Microsatellite genotyping in five of the combined tumours displayed an identical heterozygous pattern with paired Fallopian tube tissue, indicative of a somatic cell origin. In addition, paired box protein 8, a highly sensitive Müllerian epithelial marker, was not detected by immunohistochemistry in either tumour component in any of the ten tumours, suggesting that this subset of mucinous tumours does not originate from Müllerian-derived epithelium. In conclusion, this study demonstrates that in combined mucinous and Brenner tumours, there is a shared clonal relationship between the two different tumour components and suggests that some pure mucinous tumours may develop from a Brenner tumour in which the Brenner tumour component becomes compressed and obliterated by an expanding mucinous neoplasm.