Impact of comorbidity on survival for locally advanced head and neck cancer patients treated by radiotherapy or radiotherapy plus chemotherapy.

BACKGROUND The aim of this study was to investigate the impact of comorbidity on survival for patients with locally advanced head and neck squamous cell carcinoma (HNSCC). METHODS A total of 214 patients with locally advanced HNSCC, treated with radiotherapy (RT) or RT plus chemotherapy (CT) from January 2000 to December 2003, were included. Comorbidity was scored by the Charlson comorbidity index (CCI). The patient-, tumor-, and treatment-related variables were recorded and overall survival (OS) and disease specific survival (DSS) were calculated. RESULTS Seventy-one patients (33%) had at least one comorbid condition. The most common comorbid condition was liver disease (13.6%). Higher CCI scores were not significantly correlated with exposure to smoking, alcohol, or betel quid, but were associated with older age, fewer years of education years, and no CT (p<0.05). The 3-year OS and DSS rates were, respectively, 21.9% and 24.4% for all patients; 25.9% and 26.9% for those with CCI scores of 0, 21.8% and 28.3% for scores of 1, and 3.5% and 7.5% for scores>or=2. Multivariate analysis revealed that a CCI score>or=2, stage IV disease, a RT dose<70 Gy, and no CT were significant predictors of poorer OS and DSS. CONCLUSIONS Our data reveal the significant survival impact of comorbidity on patients with locally advanced HNSCC treated by RT or RT plus CT.