BACKGROUND:

The association between Brenner tumor and pregnancy is extremely rare. Only four well-documented cases of benign Brenner tumor during pregnancy have been reported but nonmalignant.

CLINICAL CASE:

A 33-year-old female patient, with a history of a pregnancy that ended in delivery and without setbacks, with no medical or surgical history of interest. In the ultrasound scan of the twelfth week, a 41 mm smooth-walled sonoluscent image was recorded in the left ovary. Lumpectomy was performed during cesarean section. Histological study described a transitional cell epithelial neoplasm, with benign, proliferative and infiltrative areas, compatible with a malignant Brenner tumor. She was treated with radical ovarian cancer surgery and adjuvant chemotherapy.

CONCLUSION:

It is important to keep malignant Brenner's tumor in mind as a diagnosis of exclusion in the presence of rapidly and rapidly growing tumors during pregnancy. It is very important to evaluate the appendages in all follow-up ultrasounds during pregnancy.