[Obesity as a factor in the development of cancer in type 2 diabetes].

OBJECTIVE

The aim of this study was to evaluate the prevalence of malignant tumors in patients with type 2 diabetes and the factors contributing to the development of cancer.

METHODS

Medical records of 1087 patients with type 2 diabetes were retrospectively analyzed and a group of 74 (6.8%) patients with malignant tumor were found during treatment of diabetes.

RESULTS

The most common sites of malignancies in patients with type 2 diabetes were: kidney (33.3%) and colorectal cancer (26.7%). The highest mean body mass index (BMI) was in the group of patients with uterus cancer and amounted to 36.1 kg/m². The next highest BMI recorded in the case of breast cancer - 32.6 kg/m², cancer of the kidney - 31.6 kg/m² and colorectal cancer - 31.3 kg/m². The lowest BMI values were observed in gallbladder cancer - 25.2 kg/m² and lung cancer - 26.4 kg/m². BMI in the various types of cancer were not statistically significant. In the group with normal BMI prostate cancer was most common. In the group of overweight and obesity patients kidney and colon cancers occurred more frequently, while in obese women - breast and uterus tumors. More than 80% of patients with type 2 diabetes who were diagnosed with cancer were overweight or obese. In the group of obese patients the highest average glycated hemoglobin was observed and if compared to those with normal weight it was significantly higher (p = 0.01).

CONCLUSIONS

In the group of obese patients, the most common tumors were renal and colorectal cancer, and cancer of the breast and uterus in a group of obese women. The use of metformin in the presence of other risk factors do not protect against the development of cancer.