Merkel cell carcinoma incidence, trends, and survival rates among adults from United States cancer statistics during 2000-2022.

e21560 Background: Merkel cell carcinoma (MCC) is a rare form of skin cancer that frequently metastasizes and is associated with low survival rates. Studies that describe the epidemiology of MCC are often limited by small sample size and short duration of follow-up. Methods: This is a retrospective, population-based epidemiologic study of all cases of MCC from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2022. Incidence and mortality rates were calculated using SEER*Stat software and SEER 17 (2000-2022) that covers approximately 26.5% of the U.S. population (based on 2020 census). Results: In total, 12,291 patients were identified between 2000-2022. Most cases are diagnosed at 2021 (716 cases) averaging 0.7 per 100 000 person-years. MCC incidence rates increased with increasing age among male and female with the majority of patients age 85+ (p < .05). There is a higher incidence in male (7,857 total cases) than female (4,434 total cases). Incidence is also higher among white patients (11,662 cases) (94.90%) than black patients (168 cases). Most of MCC are located in head and neck region with about (4319 cases). The annual percent change in incidence rates was highest among 65–69-year-olds and black people. Observed five years survival rate 48.70% (95% CI 47.5%-49.9%). Diagnosis between 2017-2022 was associated with improved survival. Conclusions: This study demonstrates that most patients were white, male, and age 85+.Head and neck region is the commonest site of tumour. Recent diagnosis was associated with improved survival.