Prospective Multicenter Cohort Study of Clinical and Molecular Biomarkers in Colorectal Cancer

Colorectal cancer is a heterogeneous disease characterized by substantial variability in tumor biology, treatment response, and clinical outcomes. The identification of reliable molecular biomarkers may improve risk stratification, facilitate the detection of disease recurrence, and support the development of personalized treatment strategies. This prospective, multicenter observational cohort study aims to establish a longitudinal biobank of biological specimens linked to comprehensive clinical data from patients with colorectal cancer undergoing surgical treatment. Biological specimens, including tumor tissue, adjacent non-malignant tissue, and peripheral blood, will be collected and stored for molecular and biochemical investigations. Serial blood sampling during follow-up will enable the investigation of longitudinal changes in circulating biomarkers and their potential association with disease progression, treatment response, and clinical outcomes. Planned research activities include molecular characterization of tumor tissue, analysis of circulating tumor DNA (ctDNA), investigation of tumor-associated genetic alterations, gene expression profiling, and measurement of circulating biomarkers. Where feasible, patient-derived tumor cells may also be isolated and cultured for exploratory investigations. Clinical information, including tumor characteristics, treatment modalities, and disease course, will be documented prospectively and linked to the collected biological specimens. This integrated approach will enable the investigation of associations between molecular characteristics, longitudinal biomarker dynamics, and clinical outcomes. The study is intended to provide a comprehensive research resource for identifying and validating prognostic and predictive biomarkers in colorectal cancer. All diagnostic and therapeutic decisions will be made according to routine clinical practice and will not be influenced by study participation.