The Impact of Comorbidity and Age on Survival with Laryngeal Cancer

Abstract
Previous studies have evaluated the effects of comorbidity on survival in patients with cancer. We applied the Charlson comorbidity index (CCI) to a cohort of patients with laryngeal cancer to validate its use and to assess the prognostic impact of age. Our study population consisted of 152 patients with laryngeal cancer who were seen over a 10-year period. Patients were assigned CCI scores and were categorized into low- and high-grade comorbidity groups for comparison. Age adjustments were performed by adding 1 point to the Charlson score for each decade over the median age. Low- vs. high-grade comorbidity was a valid predictor of survival independent of TNM (tumor, nodes, and metastases) stage. Low-grade comorbidity was present in 126 patients; their median survival was 41 months. High-grade comorbidity was present in 26 patients; their median survival was 8 months (p = 0.0002). The addition of the age factor to the CCI did not improve our prognostic ability. There was no difference in CCI groups with respect to tobacco and alcohol use, gender, treatment modality, or mean time to recurrence. The incidence and severity of complications were also similar in the two groups. We conclude that the CCI is a strong predictor of survival inpatients with laryngeal cancer. The confounding effects of comorbidity should be considered in the TNM staging of laryngeal cancer to improve our prognostic ability. Further investigations are necessary to assess the validity of this index inpatients with other head and neck cancers.