Examining the Outcomes of Palliative Oophorectomy of Ovarian Metastases in de-Novo Metastatic Colorectal Cancer and Its Association with RAS Mutation Status: Insights from a Single-Institution Perspective.

Abstract

Background and aim: Ovarian metastasis occurs in 3-5% of patients with CRC. Ovaries are considered sanctuary sites and typically do not respond effectively to chemotherapy. Patients with KRAS mutation generally have a worse prognosis compared to those with KRAS wild type. This study will discuss the effect of palliative oophorectomy on survival rates for those patients compared to chemotherapy alone.

Methods: This is a retrospective study; we reviewed the charts of patients diagnosed with metastatic colorectal cancer at KHCC between January 2015 and December 2022. Out of 862 patients, 50 patients were eligible for the study; Patients were divided into two groups based on their treatment type, the palliative oophorectomy group and the chemotherapy alone group. The primary endpoint was a three-year median overall survival rate between the two groups. The secondary endpoints included three-year median progression-free survival and the difference in survival rate between the groups based on KRAS and BRAF mutation status.

Results: In the oophorectomy group, the median overall survival (OS) was 19.3 months compared to 10.3 months in the chemotherapy alone group, with a P value of 0.05. Median progression-free survival (PFS) was also better in the oophorectomy group at 14.6 months compared to 9.4 months, with a P value of 0.59. For patients with KRAS mutation who underwent oophorectomy, the median OS was significantly better at 29.1 months compared to 10.3 months in the chemotherapy alone group, P value of 0.03.

Conclusion: Our study indicates that palliative oophorectomy in metastatic CRC is associated with better survival. Even patients who harbor mutated KRAS, which typically have more aggressive disease behavior, showed better survival outcomes with oophorectomy compared to systemic chemotherapy alone.