Impact of baseline body mass index on the outcomes of patients with neuroendocrine neoplasms.

OBJECTIVE

To assess the impact of baseline body mass index (BMI) on the outcomes of patients with neuroendocrine neoplasms (NENs) in a population-based setting.

METHODS

Linked provincial administrative databases (within the province of Alberta, Canada), 2004-2019, were accessed, and patients with NENs and complete information about BMI near the time of diagnosis were reviewed. The impact of BMI on overall survival was evaluated through the use of Kaplan-Meier survival estimates and multivariable Cox regression modeling.

RESULTS

A total of 1010 patients with NENs and BMI information were included. Using Kaplan-Meier survival estimates, survival outcomes were best with individuals with obesity and were worst with underweight individuals (P < 0.0001). The following factors were associated with worse overall survival, older age (HR: 1.02; 95% CI: 1.01-1.03), male sex (HR: 1.60; 95% CI: 1.32-1.93), higher Charlson comorbidity index (HR: 1.22; 95% CI: 1.13-1.31), non-small intestinal primary (HR for gastric primary versus small intestinal primary: 2.36; 95% CI: 1.44-3.85), stage 4 disease (HR: 2.67; 95% CI: 2.16-3.31), neuroendocrine carcinoma histology (HR: 1.76; 95% CI: 1.43-2.17), and underweight BMI (HR versus normal BMI: 1.74; 95% CI: 1.11-2.73). When the model was repeated using BMI as a continuous variable (rather than as a categorical variable), increasing BMI was associated with better overall survival (HR with increasing BMI: 0.97; 95% CI: 0.95-0.98).

CONCLUSIONS

Lower BMI is associated with worse overall survival among patients with NENs. This finding was demonstrable regardless of the tumor's stage or histology.