To evaluate the clinicopathological features and outcomes of patients undergone surgery for benign and metastatic adnexal masses during the surveillance of colorectal cancer (CRC).

A single institute retrospective study involving 90 patients diagnosed with CRC that undergone surgery at Hacettepe University Hospital between 2000−2018. Clinicopathological and survival data was obtained from hospital records.

Elevated blood levels of CEA (HR, 1.23; 95 % CI: 1.03–1.24; p = 0.01), adnexal masses larger than 5 cm (HR, 3.296; 95 % CI: 1.527–7.076; p = 0.002), bilaterality of adnexal mass (HR, 2.200; 95 % CI: 2.464–11.969; p = 0.001) and high PCI score (HR, 0.150; 95 % CI: 0.044−0.479; p = 0.01) were found to be significantly associated with ovarian metastasis. There was a significant difference in overall survival (OS), with respect to complete and incomplete resection in adnexal surgery of ovarian metastasis (46.6 vs. 29.6 months; p = 0.004). The median survival time was 32.8 months for patients with ≤ 24 months interval time to adnexal metastasis surgery, and 48.5 months for patients with >24 months interval time to adnexal metastasis surgery (p = 0.001).

This study showed that numerous clinicopathological variables such as bilaterality and size of adnexal mass, serum blood levels of CEA and PCI score may have a significant impact on the prediction and management of ovarian masses diagnosed during CRC surveillance. Complete resection and interval time to adnexal surgery is significantly associated with OS.