The Effect of Type 2 Diabetes Mellitus on the Short-Term Outcomes and Prognosis of Stage I–III Colorectal Cancer: A Propensity Score Matching Analysis

PURPOSE: The purpose of the current study was to analyze the effect of type 2 diabetes mellitus (T2DM) on the short-term outcomes and prognosis of stage I–III colorectal cancer (CRC) undergoing primary surgery. METHODS: Patients who underwent primary CRC surgery were retrospectively collected from Jan 2011 to Jan 2020 in a single clinical center. The short-term outcomes and prognosis were compared between T2DM group and non-T2DM group using propensity score matching (PSM) analysis. RESULTS: A total of 4250 patients were included in this study. There were 521 patients with T2DM and 3729 patients without T2DM. After 1:1 ratio PSM, there were 519 T2DM patients and 519 non-T2DM patients left in this study. No significant difference was found in baseline information after PSM (p>0.05). T2DM had higher overall complications (p=0.033) after PSM in terms of short-term outcomes. As for prognosis, T2DM group had worse overall survival (OS) in all stages (p=0.044), stage I (p=0.009) and stage II (p=0.021) of CRC and T2DM group had worse disease-free survival (DFS) than non-T2DM group in stage I (p=0.008) of CRC before PSM. However, T2DM did not affect the overall survival (OS) or disease-free survival (DFS) on different stages of CRC after PSM (p>0.05). Moreover, T2DM was not an independent predictor of OS or DFS (p>0.05). CONCLUSION: T2DM increased overall complications after primary CRC surgery. However, T2DM might not affect OS and DFS of stage I–III CRC patients.