Staging procedures in patients with mucinous borderline tumors of the ovary do not reveal peritoneal or omental disease.

OBJECTIVES: Staging in case of a borderline tumor of the ovary (BOT) is a controversial issue. Upstaging is not uncommon, but this occurs especially with presumed stage I serous borderline tumors. There are only a few documented cases of BOTs of non-serous histology that were not confined to the ovary. The aim of this study was to assess the incidence of non-invasive and invasive implants in the omentum and other (extra)pelvic peritoneal surfaces in patients with a mucinous BOT (mBOT).

METHODS: A retrospective cohort study was performed in three hospitals in the Netherlands. All patients with a histopathological diagnosis of mBOT diagnosed from January 1st 1990 to December 1st 2015 were identified and included when the inclusion criteria were met.

RESULTS: In total, 74 patients were included. Of these 74 patients, 46 (62.2%) underwent a staging procedure. In 12 (26.1%) patients, only omental tissue was obtained, in 32 (69.6%) patients, omental tissue and peritoneal biopsies were obtained and in two (4.3%) patients, only peritoneal biopsies were obtained. No implants were seen upon microscopic examination in any of the patients. Two patients (3%) developed a recurrence.

CONCLUSIONS: Because no extra-ovarian disease was found, staging procedures in the case of an mBOT may be omitted. However, the actual perioperative decision for staging or not should be taken in the context of a frozen section diagnosis, which is not always accurate and straightforward. Recurrence with malignant disease is rare after mBOT. The value of post-treatment surveillance seems limited after bilateral salpingo-oophorectomy.