A SEER program study of survival trends in Merkel cell carcinoma of the eyelid: 2000-2019.

PURPOSE: Merkel cell carcinoma of the eyelid (MCCE) is a rare yet aggressive neuroendocrine tumour associated with significant morbidity and mortality. This study aimed to investigate survival trends and demographic factors related to MCCE, 2000-2019, using the Surveillance, Epidemiology, and End Results (SEER) Program.

METHODS: Cases were analysed by demographic parameters, disease properties, and survival. Statistical analyses were performed via a dedicated computerized software package.

RESULTS: A total 349 cases of MCCE were identified, accounting for 2% of all MCC cases in the United States during that time. Of note, the incidence of MCCE remained stable over the study period ( p  = .35). Female patients accounted for 56% of the cases, and males for 44%. White patients accounted for 90.8% of the the cases, and Black patients for 2.9%. MCCE incidence increased with age, with the majority of patients age 85+ ( p  < .05). Incidence was greatest in metropolitan areas and among those with median incomes >$75,000/year. Income correlated with likelihood of MCCE diagnosis ( p  < .05). Analysis of 5-year survival data showed 20% of the patients died due to MCCE within 5 years of diagnosis. Of these, the majority died within one year of diagnosis.

CONCLUSIONS: Consistent with previous reports, most patients were white, female, and age 85+.Incidence correlated with metropolitan environments and median income. While most patients did not die from MCCE, majority of recorded deaths occurred within one year of diagnosis.