Body mass index at diagnosis and prognostic significance on head and neck carcinoma survival

Abstract

Abstract Background Previous findings suggest there might be an inverse association between body mass index (BMI) and overall (OS) and Head and Neck-specific survival. The aim of this study was to investigate the prognostic role of BMI in the largest available cohort of HNC patients. Methods We performed a pooled analysis of studies participating at the INHANCE consortium. Cases were adults with HNCs of the oral cavity, oropharynx, hypopharynx and larynx. We used cox's proportional hazards models to estimate the relationship between BMI and overall and HNC-specific mortality. Sensitivity analysis were performed according to tumour location, smoking status and length of follow-up. Results The study included 9484 patients from 10 centres worldwide for a median follow-up of 48 months (IQR: 18-69). Overall 3623 patients (38.2%) died from all-causes and 1493 (15.7%) from HNC. Compared to patients with a normal weight, overweight or obese was associated with a longer HNC-specific survival (HR = 0.58, 95% CI: 0.35-0.95, HR = 0.37, 95% CI: 0.17-0.78, respectively), while underweight was associated to a shorter survival (HR = 1.73, 95% CI: 1.36-2.21). Results were heterogeneous according to tumour site, with the strongest effect among oropharynx and oral cavity cancer sites. When we restricted the analysis among patients with a follow-up longer than 5 years, underweight (HR = 5.17, 95% CI: 3.02-8.86) was associated with shorter HNC-specific survival. Conclusions Our findings suggest low BMI values are at diagnosis increase mortality in HNC patients. The protective effect of high BMI might be partially explained by residual confounding and reverse causality, so that further research is needed to clarify the potential role in tertiary prevention of BMI. Key messages BMI at diagnosis is a prognostic factor of HNC. Low BMI values predict unfavourable outcomes.