Impact of low-dose regorafenib on survival outcomes in patients with metastatic colorectal cancer: A retrospective study from a tertiary care center in South India

ABSTRACT Background: Metastatic colorectal cancer (mCRC) poses a significant health challenge, with limited treatment options and poor survival outcomes. Regorafenib, an oral multikinase inhibitor, is effective for patients with mCRC who have progressed after multiple chemotherapy lines. This study evaluates the impact of low-dose regorafenib on survival outcomes in patients at a tertiary care center in South India. Objectives: The primary objective was to determine overall survival outcomes associated with regorafenib in South Indian patients with prior colorectal cancer (CRC) treatment. Secondary objectives included assessing progression-free survival (PFS), safety profiles, and prognostic factors linked to regorafenib use. Materials and Methods: We analyzed patients treated with regorafenib from January 2015 to December 2023 in the Department of Medical Oncology at Amrita Institute of Medical Sciences, Kochi. Patient characteristics, including age, sex, primary tumor location, and metastatic sites, were recorded. PFS and overall survival (OS) were assessed, alongside treatment responses as per Response Evaluation Criteria for Solid Tumors (RECIST) version 1.1 criteria and adverse events (AEs) leading to treatment discontinuation. Results: We enrolled 81 patients, predominantly males (66.7%), with a mean age of 59.8 years. Distant metastasis at presentation occurred in 84% ( n = 68) of patients. The median PFS was 9.2 months (95% CI, 8.05-10.35), while the mean OS was 39.2 months (95% CI, 33.3-45.1). The overall response rate was 13.5%, and AEs leading to discontinuation were noted in 16% ( n = 13) of patients. Conclusion: Low-dose regorafenib demonstrated effectiveness, with favorable PFS and OS outcomes. Age and gender were identified as significant prognostic factors.