A Serous Borderline Tumor of the Fallopian Tube Detected Incidentally

Serous borderline tumor of the fallopian tube is a very rare entity and is usually diagnosed incidentally. We present here such a case which is incidentally diagnosed during lower segment cesarean section. Patient is a 31 year old lady who presented at 38 wks of gestation, underwent Lower Segment Caesarean Section (LSCS). A 3.5 cm thin walled benign looking cyst protruding from the fimbrial end of the left tube was found. The contralateral fallopian tube and ovaries were unremarkable. Exploration of the abdomino-pelvic cavity has showed no other abnormal finding. Cystectomy was performed. On histopathology diagnosis of serous borderline tumor (SBT) of the fallopian tube was made which was further confirmed by Wilm's Tumor 1 (WT1) staining. In literature, only 9 cases have been reported. And the current case is the first report in Pakistan as far as we know. Treatment for SBTs of fallopian tube is complete excision like borderline ovarian tumor. Recurrence has not been reported with up to 6 years follow up in 9 cases.