Causes of long-term mortality in patients with head and neck squamous cell carcinomas

Purpose: After treatment of a head and neck squamous cell carcinoma (HNSCC), patients with an adequate control of the tumor have a decreased overall survival when compared to age- and gender-matched controls in the general population. The aim of our study was to analyze the causes of long-term mortality in patients with HNSCC. Methods: We carried out a retrospective study of 5122 patients with an index HNSCC treated at our center between 1985 and 2018. We analyzed the survival considering three causes of death: mortality associated with the HNSCC index tumor, mortality associated with a second or successive neoplasm, and mortality associated with a non-cancer cause. Results: After the diagnosis of an HNSCC the most frequent cause of death is the head and neck tumor itself during the first 3.5 years of follow-up. Thereafter, mortality is more frequently associated with competing causes of death, such as second malignancies and non-cancer causes. Mortality associated with second and successive neoplasms was 2.3% per year, a percentage that was maintained constant throughout the follow-up. Likewise, mortality attributable to non-cancer causes was 1.6% per year, which also remained constant. There were differences in the mortality patterns according to the characteristics of the patients. Conclusion: There are differences in the mortality patterns of patients with HNSCC depending on their characteristics. Knowledge of these patterns can help in the design of guidelines to improve the follow-up protocols of this group of patients to optimize the clinical cost-effectiveness.