Survival benefit from ovarian metastatectomy in colorectal cancer patients with ovarian metastasis: a retrospective analysis

A recent study demonstrated that colorectal cancer (CRC) with ovarian metastases was less responsive to chemotherapy compared with extraovarian metastases. Hence, the ovary may actually represent a "sanctuary" for metastatic cells from CRC. The aim of the study was to investigate the impact of ovarian metastatectomy on survival of CRC patients with ovarian metastasis. Between 1996 and 2008, 83 CRC patients underwent an oophorectomy. For the historical control, 47 CRC patients with ovarian metastasis without resection were included in the analysis. The median age was younger (48 years) in the oophorectomy group compared with the historical control (54 years; P = 0.012). The proportion of synchronous metastasis was higher in the oophorectomy group than in the control group (57 vs. 30%; P = 0.003). After a median follow-up duration of 60.8 months (range of 7.4-169.7 months), the median OS was significantly longer in the oophorectomy group (28.1 vs. 21.2 months, oophorectomy vs. non-oophorectomy; P = 0.038). For ovary-specific survival (date of ovarian metastasis diagnosis to death), CRC patients with an oophorectomy showed a significantly more favorable survival rate than the control group (20.8 vs. 10.9 months; P < 0.001). In univariate analyses, oophorectomy (P = 0.038), unilaterality of ovarian metastasis (P = 0.032), metastasis confined to ovaries (P < 0.001), normal CEA level (P < 0.001), good performance status (P = 0.001), palliative chemotherapy (P = 0.001), and primary disease resection (P = 0.005) were identified as significantly good prognostic factors for overall survival. The oophorectomy, chemotherapy, metastasis confined to ovaries, normal CEA level, and good performance status retained statistical significance at the multivariate level (P = 0.003, P = 0.004, P = 0.005, P = 0.015, and P = 0.029, respectively). Based on this retrospective analysis, the ovarian metastatectomy significantly prolonged survival in CRC patients with ovarian metastases. The potential role of an ovarian metastatectomy in the management of CRC should be prospectively studied.