Objective Ovarian metastases occur in 3%–5% of patients with colorectal cancer. The role of oophorectomy in that setting continues to be debated. We aimed to assess the survival of women treated with metastasectomy for ovarian metastasis.

Methods Retrospective cohort study of patients in the California Cancer Registry (2000–2012) with stage IV colorectal cancer and ovarian metastases. Pathology other than adenocarcinoma was excluded. Adjusted Cox-proportional hazard analysis was applied to assess the risk of death.

Results A total of 756 patients with synchronous ovarian metastases and 516 patients with metachronous ovarian metastases form the basis of this analysis. Median follow-up for the synchronous cohort was 21 months (IQR: 8–36). Median overall survival was 23 months (IQR: 10–42). Estimated 5-year survival reached 17% and 10-year survival was 8%. There was a significant difference in unadjusted survival between patients with solitary ovarian metastasis (median overall survival: 51 months) compared with those who had both ovarian and extraovarian metastases (20 months) (log-rank test, P<0.0001). For patients with solitary ovarian metastases, the 5- and 10-year survival was 46% and 31%, respectively. Among patients with synchronous ovarian metastases, longer unadjusted survival was observed after oophorectomy (median overall survival: 24 months) compared with no oophorectomy (18 months, log-rank P=0.01). For patients with metachronous diagnoses of colorectal cancer ovarian metastasis, the median disease-free survival was 19 months. The median survival after resection of metachronous ovarian metastases was 25 months, with the survival directly related to the disease-free interval until metastasis. For patients with resected metachronous ovarian metastases, the 5- and 10-year post-metastasectomy survival was 14% and 5%, respectively.

Conclusions Patients with colorectal cancer ovarian metastasis have favorable long-term survival. Survival rates are higher if the tumor is isolated to the ovary or if metachronous to the primary cancer.