Type 2 Diabetes Mellitus and Non-Metastatic Colorectal Cancer: A Retrospective Study on Survival and Toxicity...

Being one of the most common cancers accounting for approximately 185 million cases globally, colorectal cancer (CRC) is one of the leading derivers of cancer-related mortalities. A high prevalence of Type 2 diabetes mellitus and CRC was noted, together with a causal link between diabetes and CRC development. Thereby, the goal of this study was to properly evaluate type 2 Diabetes mellitus in non-metastatic colorectal cancer patients, and to highlight its impacts on patient's outcome.

Patients with non-metastatic colorectal cancer diagnosed between January 2016 and December 2020 were studied retrospectively. Patients were divided into two groups based on whether or not they had type II diabetes. The clinico-pathological, laboratory, treatment and survival data were gathered.

A total of 318 patients were included in this study. The toxicity of the drugs used in CRC patients receiving the treatment protocols (169 in non-T2DM group and 39 in T2DM group), both groups reported close percentage of side effects and  a similar frequency of drug toxicity occurrence as well as grade of toxicity, with the exception of neuropathy, which was more common in the T2DM group (33.3% vs 11.2%). As for prognosis, non-T2DM and T2DM patients had a mean progression free survival of (71.4 and 60.83 months, respectively) (p = 0.019). Overall survival was 73.1% for T2DM and 85.3% for non T2DM cases. The median overall survival was not reached for both groups in terms of overall survival.

T2DM is considered a risk factor for poor survival among CRC patients. Treatment related toxicity is not affected by the presence or absence of diabetes, yet neuropathy needs further studies for diabetic patients receiving oxaliplatin.