Age is not a predictor of prognosis in metastatic cutaneous squamous cell carcinoma of the head and neck

Background: Metastatic cutaneous squamous cell carcinoma of the head and neck (cHNSCC) is more common in older patients. It is postulated that the age-related decline in immunity plays a role in cancer predisposition and prognosis. We aimed to investigate the effect of age on outcomes in cHNSCC and compare these with the outcomes of patients with cHNSCC and known immunosuppression. Methods: Patients with metastatic cHNSCC treated with curative intent were identified from a prospectively collated database of head and neck cancers at the Sydney Head and Neck Cancer Institute. Patients with cHNSCC with known immunosuppression provided a comparison group for analysis of disease-specific outcomes. Results: The study cohort includes 418 immunocompetent patients with metastatic cHNSCC (median age: 73years (interquartile range: 65-81years)) and the control cohort includes 24 patients with metastatic cHNSCC and immunosuppression (median age: 51years (interquartile range: 42-62years)). Increasing age was not associated with poorer disease-free or disease-specific survival. Patients in older age groups (70 years and over) had better disease-specific outcomes than patients with long-term immunosuppression. Patterns of disease failure did not differ between different age groups. The number of positive nodes and extra-capsular spread were the only significant prognostic variables in multivariable analysis. Conclusion: In the context of metastatic cHNSCC, age should not be considered as a marker of poor prognosis. Age should not be considered a surrogate marker of immune function considering the poorer outcomes seen in patients with immunosuppression. Older patients with metastatic cHNSCC should be considered candidates for standard treatment if otherwise medically fit.