Association of cancer mortality with postdiagnosis overweight and obesity using body mass index

Although overweight and obesity increase cancer risk, it is still controversial with respect to cancer mortality. In the current study, we enrolled 2670 patients of 14 tumor types from the Cancer Genome Atlas (TCGA) project, to identify the prognostic role of overweight and obesity in cancer patients. After dividing the patients into different groups by the body mass index (BMI), we found significant lower mortality in the obesity group. In addition, we also treat BMI value as a binary categorical variable or continuous variable, respectively. We found significant lower mortality in the higher BMI group. Furthermore, when focusing on each tumor type, cervical cancer and bladder cancer showed lower mortality in the patients with higher BMI values. Taken together, our results demonstrate that postdiagnosis obesity might indicate a better prognosis in cancer patients. However, these findings should be interpreted cautiously because of small sample size.