OBJECTIVES:  This study analyzed real-world first-line treatment patterns and predictors of 1-year and 5-year overall survival (OS) among Medicare enrollees diagnosed with metastatic Merkel cell carcinoma (mMCC), a rare neuroendocrine carcinoma of the skin. METHODS:  We analyzed Surveillance, Epidemiology and End Results (SEER)-Medicare data of patients aged ≥65 years diagnosed with stage IV MCC from 2006-11. Patients were required to have non-HMO Medicare eligibility for ≥12 months before and ≥4 months after diagnosis. Treatment received within 4 months after diagnosis was considered first-line treatment. One-year and 5-year cumulative OS were analyzed using Kaplan-Meier estimators. Predictors for 1-year and 5-year OS were analyzed using Cox regression with months of survival as a dependent variable and age at diagnosis, Charlson comorbidity score, type of first line treatment received, race, gender, and median zip-level income estimate as predictors. RESULTS: We identified 94 patients diagnosed with mMCC. At diagnosis, mean age was 81 years (SD=7.8), 72% (N=68) were male. Mean length of follow-up was 14.2 months (SD=11.3 months). The cumulative proportion of mMCC patients surviving was 56% at 1-year and 16% at 5-years. Eighty-three percent (N=78) of patients received first-line treatment, including surgery in 38% (N=36), radiation therapy in 39% (N=37), and chemotherapy in 46% (N=43). There were no significant differences in 1-year survival by age, sex, comorbidity, race, income, or type of treatment received at follow-up. Age ≥70 years (p=.018) and comorbidity score ≥1 (p=.013) were negative predictors of 5-year OS. Type of initial treatment did not predict OS at 5 years. CONCLUSIONS:  Survival for mMCC patients is generally poor, and is adversely impacted by older age and higher comorbidity at time of diagnosis. Type of treatment received at diagnosis does not appear to impact survival, although unmeasured factors influencing selection of treatment may impact our findings.