Impact of scalp location on survival in head and neck melanoma: A retrospective cohort study

Background: Scalp melanomas have more aggressive clinicopathological features than other melanomas and mortality rates more than twice that of melanoma located elsewhere. Objective: We sought to describe the survival of patients with scalp melanoma versus other cutaneous head and neck melanoma (CHNM), and explore a possible independent negative impact of scalp location on CHNM survival. Methods: A retrospective cohort study was performed of all invasive primary CHNM cases seen at a tertiary referral center over a 20-year period. Melanoma-specific survival (MSS) was compared between scalp melanoma and other invasive CHNM. Multivariable Cox proportional hazards regression was performed to determine associations with survival. Results: On univariate analysis, patients with scalp melanoma had worse MSS than other CHNM (hazard ratio 2.22, 95% confidence interval 1.59-3.11). Scalp location was not associated with MSS in CHNM on multivariable analysis (hazard ratio 1.11, 95% confidence interval 0.77-1.61) for all tumors together, but remained independently associated with MSS for the 0.76-to 1.50-mm thickness stratum (hazard ratio 5.51, 95% confidence interval 1.55-19.59). Limitations: Disease recurrence was not assessed because of unavailable data. Conclusion: The poorer survival of scalp melanoma is largely explained by greater Breslow thickness and a higher proportion of male patients.