Multicenter Retrospective Study on Optimizing Combination Immunotherapy Strategies in MSS/MSI-L/pMMR Advanced Colorectal Cancer

"Bevacizumab is an anti-vascular endothelial growth factor (VEGF) monoclonal antibody used in combination with chemotherapy or immunotherapy for the treatment of metastatic colorectal cancer (CRC). In this study, bevacizumab is administered as part of combination therapy in certain patient groups to assess its impact on treatment efficacy in MSS/MSI-L/pMMR advanced colorectal cancer.~Patients receiving bevacizumab will be evaluated for treatment response, survival outcomes, and potential biomarkers predictive of therapeutic efficacy. The study will compare the clinical benefits of immunotherapy alone, immunotherapy + bevacizumab, and immunotherapy + chemotherapy + bevacizumab to determine the optimal treatment strategy.~The dose and administration schedule of bevacizumab will follow standard clinical guidelines as per institutional protocols."