Treatment Strategies' Impact on Progression-Free Survival According to RMST Function in Metastatic Colorectal Cancer Patients: A Retrospective Study from Romania

This retrospective study investigates the impact of various treatment strategies on progression-free survival (PFS) in patients with metastatic colorectal cancer (mCRC), a significant global health issue. We employed the restricted mean survival time (RMST) to evaluate how different treatments affect PFS over a defined period. The study included 225 patients with mCRC who were treated between 2015 and 2023 at the Oncology Department of Colțea Clinical Hospital in Bucharest. To assign KRAS status, mutation data from exons 2, 3, and 4 of the KRAS gene were required. Eligibility criteria included a confirmed histopathological diagnosis of colorectal adenocarcinoma, a valid RAS mutation test from a solid biopsy, radiological confirmation of stage IV disease by computed tomography, and at least one line of systemic treatment in the metastatic setting. Our analysis revealed a small difference in PFS based on KRAS status, but this difference was not statistically significant. Neither sex nor the urban versus rural environment impacted PFS; however, the data indicated that educational level affected survival outcomes. Consistent with existing literature, our findings showed no survival benefit from locoregional treatments such as surgery of the primary tumor or curative radiotherapy at diagnosis. In contrast, resection of hepatic metastases was associated with improved survival outcomes.