Risk-adapted management of early-stage malignant Brenner tumor: eight-year outcomes and contemporary evidence review-a case report.

A 54-year-old postmenopausal Black African woman, G4P4, with no significant medical and psychosocial history, presented for routine cervical cancer screening. During the consultation, she reported intermittent episodes of postmenopausal metrorrhagia, prompting a comprehensive gynecological evaluation. Her general condition was good, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0. Physical examination revealed no abdominal masses. The cervix appeared normal with no signs of tumor involvement, and the parametria were supple. The cervico-vaginal cytology was negative for intraepithelial lesion or malignancy. Transvaginal ultrasonography identified a heterogeneous, hypervascular right adnexal mass. The uterus appeared normal, with a thin, regular endometrium measuring 3 mm, showing no features suggestive of hyperplasia or malignancy. Subsequently, pelvic magnetic resonance imaging (MRI) demonstrated a 5.5 cm multiloculated right ovarian mass with mixed solid and cystic components. The solid components showed restricted diffusion and a type 3 enhancement curve on dynamic contrast-enhanced sequences, features highly suggestive of malignancy. The uterus was normal with preserved zonal anatomy and a homogeneous endometrium without focal lesions or signal abnormalities. The bladder and rectal walls were unremarkable. No ascites, peritoneal carcinomatosis, or lymphadenopathy was detected. A thoracic–abdominal–pelvic computed tomography (CT) scan confirmed the absence of distant metastases. Serum tumor markers were within normal limits, notably a CA-125 level of 16 U/mL (reference: < 35 U/mL). The patient was referred to our center after having undergone a laparoscopic total hysterectomy with bilateral salpingo-oophorectomy performed by a general gynecologist outside a specialized oncology service. The procedure was uncomplicated, with no intra-abdominal adhesions encountered, allowing for complete surgical resection and staging. Histopathological examination of the surgical specimen revealed a fibrous cervical stroma with a normal exocervical lining, a myometrium with extensive adenomyosis, and an atrophic endometrium free of hyperplasia, inflammation, or neoplasia. Both fallopian tubes were normal. The left adnexa consisted of an unremarkable ovary (3.5 × 1 × 1 cm) and a 5.5-cm fallopian tube. The right ovary, measuring 5 × 4.5 × 3 cm, contained the tumor and was associated with a 6.5-cm fallopian tube. The tumor was a solid, well-demarcated, intra-ovarian mass that extended to and effaced the ovarian surface, which lacked a definitive capsule. No exophytic or papillary surface lesions were identified. Microscopically, it displayed proliferative cellular lobules with large, condensed nuclei arranged in stacked vertical patterns, accompanied by focal glandular formations. Despite extensive sectioning, an intact mesothelial lining at the tumor–cortex interface could not be confirmed, precluding definitive assessment for capsular penetration. Immunohistochemistry was positive for p63, keratin, and vimentin, and negative for inhibin. The Ki-67 proliferation index was qualitatively assessed as markedly elevated (approximately 40–50% in the most active foci). These histopathological and immunohistochemical features confirmed the diagnosis of a malignant Brenner tumor. The available histopathology report as well as the operative report, while detailed on the uterine and ovarian specimens, did not mention the performance of comprehensive surgical staging procedures such as peritoneal washings for cytology or an omental biopsy. Therefore, the final FIGO stage IC2 (2018 criteria) was assigned based solely on the histopathological criterion detailed above (tumor abutting the ovarian surface with an indeterminable mesothelial lining), as no other staging information was available. Given aggressive histological features (elevated Ki-67), the multidisciplinary tumor board recommended adjuvant chemotherapy. The patient received six cycles of carboplatin (AUC 5) and paclitaxel (175 mg/m 2 ). No significant toxicities were observed apart from grade 1 peripheral neuropathy. Treatment adherence was maintained throughout, with all courses administered at the intended timing. Following completion of chemotherapy, serum tumor markers remained within normal limits, and control imaging showed no evidence of residual or recurrent disease. Adjuvant pelvic radiotherapy was thoroughly debated but ultimately omitted due to: (1) early disease stage, (2) absence of residual disease, (3) absence of aggressive histological components, and (4) lack of evidence supporting a survival benefit, which was weighed against the potential for radiotherapy-related morbidity. At the most recent eight-year follow-up, surveillance revealed no clinical or radiological signs of disease, and the CA-125 level remained stable and within the normal range (for example, 16 U/mL).

This case demonstrates that risk-adapted management of early-stage malignant Brenner tumor can achieve excellent long-term outcomes. Our eight-year follow-up supports contemporary paradigms that emphasize individualized risk assessment over standardized protocols. This approach represents an evolving standard for rare ovarian malignancy management, particularly in settings where evidence-based guidelines are limited. This report shares limitations inherent to rare tumor documentation. The excellent outcome may reflect early detection and favorable biology. A significant limitation stems from the initial surgery being performed outside a multidisciplinary oncology setting. Consequently, comprehensive surgical staging (peritoneal cytology, omental biopsy) was not documented, preventing the exclusion of occult microscopic disease. This scenario highlights a common and critical challenge in the management of rare ovarian tumors: the potential for incomplete initial staging when surgery is undertaken without a specialized oncology team, which may impact subsequent risk assessment and adjuvant therapy decisions. Generalizability requires validation through larger, prospectively staged series.

Our case illustrates the critical importance of risk stratification in rare ovarian malignancies. The elevated Ki-67 index, a recognized marker of high proliferative activity, further supported the decision for adjuvant chemotherapy. Although data specific to MBT are sparse, a high Ki-67 index is a well-established adverse prognostic factor across various ovarian malignancies and is often considered in risk-stratifying rare tumors where other evidence is lacking . [ 5 , 6 ] Platinum-based chemotherapy represents the most common adjuvant approach, particularly for advanced-stage or high-grade disease. Approximately 50–55% of MBTs present at stage I [ 7 , 8 ]. Current literature supports adjuvant chemotherapy from stage IC onward, while surveillance may suffice for stages IA–IB. In Han’s series, the four patients with stage IA did not receive adjuvant chemotherapy and experienced no recurrences. Gezginç reported one stage IA and two stage IB cases; only a single recurrence occurred, in a stage IB patient [ 9 – 11 ]. The carboplatin–paclitaxel regimen, adapted from epithelial ovarian carcinoma protocols, is most frequently employed. Although the carboplatin–paclitaxel regimen is predominant, other agents, including melphalan, cisplatin–paclitaxel, carboplatin–docetaxel, and cyclophosphamide–carboplatin have been reported [ 1 , 8 ]. However, the role of adjuvant chemotherapy remains poorly defined and contentious, primarily due to the reliance on retrospective data and inherent selection bias. This is exemplified by contrasting reports in the literature: while some series have documented recurrence rates as high as 53.8%, other larger cohorts have failed to demonstrate a clear survival benefit [ 8 , 11 ]. This discrepancy likely reflects significant heterogeneity in patient selection, tumor stage, and histological criteria across studies. Several reports describe successful management with surgery alone, including cases with sustained remission. King et al. reported two cases of malignant Brenner tumors treated with surgery alone. Without detailed FIGO staging, both tumors appeared ovarian-confined, and neither patient experienced recurrence at 2-month and 2-year follow-ups [ 12 ]. An analysis of SEER data from 139 patients by Ellaithy found no statistically significant difference in 5-year overall survival with adjuvant chemotherapy [ 13 ]. This evidence underscores the need for individualized treatment decisions and highlights the value of prospective registries. The role of radiotherapy in MBT management is highly contested. Historical literature documents isolated instances of irradiation for advanced or recurrent disease, with heterogeneous and often suboptimal outcomes. The application of adjuvant radiotherapy for early-stage disease remains exceptionally uncommon and lacks robust evidence. Pratt-Thomas et al. reported two patients who received postoperative whole-abdominal radiotherapy without systemic therapy; one experienced a local recurrence within two years, underscoring the modality's questionable efficacy [ 14 ]. Contemporary practice reflects this paradigm shift. A modern American review of 10 cases revealed the consistent omission of adjuvant radiotherapy [ 15 ]. A comprehensive analysis of 69 reported cases receiving adjuvant treatment for MBT identified only 7 patients (10.1%) treated with radiotherapy, 4 of whom received it concurrently with chemotherapy [ 8 ]. Similarly, in the large-cohort study by Nasioudis et al., radiotherapy was documented in a mere 2.4% of cases, though specific details regarding intent (adjuvant versus palliative) or technique were notably absent [ 7 ]. This consistently low utilization rate highlights the marginal and declining role of radiotherapy in contemporary MBT management. While isolated reports, such as one by Lang et al., describe sustained remission after postoperative irradiation for a resected localized recurrence, such examples remain exceptional [ 16 ]. Although technological advances in radiotherapy delivery and documented efficacy in other ovarian histological subtypes might theoretically renew interest in this modality, current evidence remains insufficient to justify its reconsideration for MBT outside of highly selected, investigational contexts [ 17 ]. Consequently, the current consensus and clinical evidence confine the role of radiotherapy to the management of unresectable disease, localized recurrences not amenable to surgery, or for palliative indications. Our decision to omit radiotherapy is supported by several arguments: (1) absence of efficacy evidence as there are no studies demonstrating survival or local control benefits from adjuvant radiotherapy in early-stage MBT; (2) substantial morbidity risk: pelvic radiotherapy carries significant toxicity risks without compensatory clinical benefit and (3) sufficiency of current approach: surgery with platinum-based chemotherapy provides excellent disease control. Current literature supports the safety of omitting radiotherapy in early-stage MBT, with several series reporting excellent outcomes with surgery and platinum-based chemotherapy alone. Our experience aligns with this contemporary evidence while contributing unique long-term data from an African setting.

Malignant Brenner tumor (MBT) constitutes an exceptionally rare ovarian neoplasm, representing less than 1% of all ovarian cancers and fewer than 5% of all Brenner tumors [ 1 , 2 ]. Its rarity is highlighted by a five-year multicenter pathological review in Senegal, where MBTs constituted only 0.82% of all documented malignant epithelial tumors—a finding consistent with a previous Senegalese retrospective study [ 3 , 4 ]. Surgical resection is the cornerstone of treatment, while adjuvant therapy lacks standardization due to limited data. However, adjuvant chemotherapy has become the mainstay for high-risk cases, supported by accumulating retrospective evidence. Recent systematic reviews have enabled more refined patient selection, fostering a shift toward personalized therapeutic strategies [ 2 ]. This paradigm evolution reflects the growing recognition that rare malignancies require tailored approaches based on specific risk factors. Against this backdrop, we present an eight-year follow-up of an early-stage MBT managed with contemporary risk-adapted principles, complemented by a review of current evidence.