Palliative Primary Tumor Resection in Minimally Symptomatic Patients With Colorectal Cancer and Synchronous Unresectable Metastases

The present study is a single-center retrospective observational cohort study with a propensity score matching. Between 2016 and 2022 from our institutional database minimally symptomatic patients with colorectal cancer and synchronous unresectable metastases will be selected. Patients will be divided into two groups: 1. Surgical resection of the primary tumour before to systemic therapy 2. Systemic therapy without previous resection of the primary tumour. Propensity score matching (PSM) will be performed, to minimize the selection bias by adjusting variables that may affect the survival of patients. Categorical variables will be compared using the chi-square test or Fisher's exact test. Continuous variables will be compared using the Student's t-test or Mann-Whitney U test. Survival rate will be determined by using Kaplan-Meier analysis with a log-rank test. Univariate and multivariate analyses for survival will be conducted using Cox proportional hazard models. Statistical results will be considered significant at p values less than 0.05.