Brenner borderline ovarian tumors: A series of seven cases and a literature review.

[OBJECTIVE] Brenner borderline ovarian tumor is a rare histologic subtype of borderline ovarian tumor, whose clinicopathological characteristics, management, and prognosis are poorly understood. This study presents a series of seven cases and a comprehensive literature review, with the aim of furthering our understanding of this rare disease.

[METHODS] This was a retrospective study of seven patients with pathologically confirmed Brenner borderline ovarian tumors treated at Peking Union Medical College Hospital between January 2000 and September 2025. We comprehensively analyzed the clinicopathological characteristics, treatment, and clinical outcomes of the cohort. In addition, we systematically searched four databases according to the PRISMA guidelines, and summarized previous findings from patients with this rare tumor.

[RESULTS] The median age at diagnosis in the current cohort was 56 years (range, 36-71 years), with only one premenopausal patient. Two patients underwent comprehensive staging surgery, while the premenopausal patient underwent fertility-sparing surgery. All patients in our cohort presented with disease confined to FIGO stage I, and the overall prognosis was favorable. The literature review identified 45 relevant studies and 146 previously reported cases with similar clinical characteristics. All patients with available follow-up data after fertility-sparing surgery were alive with no evidence of disease at the time of publication.

[CONCLUSION] Brenner borderline ovarian tumors are typically diagnosed at an early stage, and systematic staging surgery may thus not always be necessary. Fertility-sparing surgery is a viable option for premenopausal patients. The overall prognosis for this disease is excellent.