Abstract:

Objective: To investigate the clinicopathological and immunohistochemical characteristics of ovarian Brenner tumor. Methods: The clinical data, pathological features, immunophenotypes, and molecular characteristics of six patients with ovarian Brenner tumor between January 2019 and February 2023 at Suzhou Ninth Hospital Affiliated to Soochow University (our hospital) were retrospectively analyzed. Results: The age of the six patients varied from 54 to 73 years, with a median age of 66 years. Among these patients, four were diagnosed with benign ovarian Brenner tumor, while two were malignant. Biochemical indicators of 4 patients with benign ovarian Brenner tumor and one with malignant ovarian Brenner tumor were within normal ranges, while the level of carbohydrate antigen 125 (CA125) in another one patient with malignant ovarian Brenner tumor was significant increased. Microscopic examination revealed that the tissue of benign ovarian Brenner tumor was consisted of transitional cell epithelial nests, accompanied by fibrous stroma. These cells did not display any atypia and had oval nuclei with small nucleoli. In contrast, the tissue of malignant ovarian Brenner tumor exhibited clear stromal infiltration, evident atypia, a high nuclear plasma ratio, and increased mitotic activity, which was accompanied by benign ovarian Brenner tumor and borderline ovarian Brenner tumor components. Immunohistochemical staining showed that the tumor cells were positive for cytokeratin 7 (CK7), P63 and GATA binding protein 3 (GATA3), but negative for paired box 8 (PAX8), Wilm′s tumor gene 1 (WT1) and CK20. Ki-67 proliferation index was lowered 1% in benign ovarian Brenner tumor and about 20%-60% in malignant ovarian Brenner tumor. Four patients with benign ovarian Brenner′s tumor underwent adnexectomy on the affected side, with a good prognosis. One case of malignant ovarian Brenner′s tumor underwent laparoscopic ovarian staging surgery, and no recurrence or metastasis was found after 11 months of follow-up. Another case of ovarian malignant ovarian Brenner tumor was lost due to not undergoing surgery in our hospital. Conclusions: The diagnosis of ovarian Brenner tumor depends on the histopathological characteristics and immunohistochemistry. The differential diagnosis of benign and malignant ovarian Brenner tumor is based on the degree of cell atypia and stromal invasion. In addition, Ki-67 proliferation index can be used as a reference index.

Key words: Ovarian neoplasms, Brenner tumor, Immunophenotyping, Pathology, clinical, Diagnosis, differential