Risk of Ovarian Involvement in Advanced Colorectal or Appendiceal Tumors Involving the Peritoneum.

Background: Ovarian metastases of GI tumors grow rapidly and are relatively resistant to systemic chemotherapy. They may be unilateral or bilateral and macroscopic or occult. The risk of macroscopic ovarian involvement or occult involvement of macroscopically normal ovaries is unquantified.

Objective: This study aims to quantify the risks of ovarian involvement in patients with peritoneal malignancy undergoing cytoreductive surgery with hyperthermic intraperitoneal chemotherapy.

Design: This was a retrospective analysis of a dedicated prospective malignancy database.

Settings: This study was conducted at a high-volume tertiary referral center for peritoneal malignancy.

Patients: Female patients with at least 1 remaining ovary, undergoing complete cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for appendiceal tumors or colorectal peritoneal metastases between January 2010 and March 2015 were included.

Outcome Measures: Data regarding ovarian involvement was extracted from surgical and histological records.

Results: Two hundred fifty-eight female patients with at least 1 ovary underwent complete cytoreduction and hyperthermic intraperitoneal chemotherapy during the study period. In total, 141 of 258 (54.7%) patients had ovarian tumor involvement, and 80% with at least 1 macroscopically abnormal ovary had bilateral involvement. Of 40 patients with 1 macroscopic ovarian metastasis, microscopic involvement of the contralateral ovary was found in 18 of 40 (45.0%). Of 141 patients in whom both ovaries were macroscopically normal, 24 of 141 (17.0%) patients had microscopic ovarian involvement.

Limitations: The retrospective nature limits the interpretation of these results.

Conclusions: Occult malignancy was present in 17% when both ovaries looked macroscopically normal and in 45% of contralateral normal-looking ovaries if the other ovary was macroscopically involved. These results help to inform preoperative consent and intraoperative decision making in patients with advanced appendiceal and colorectal malignancy, and are of benefit in managing advanced lower GI tract malignancy.