Presence of ulceration (HR = 2.22; 95% CI= 0.99–4.98; p = 0.05) and an increased N:CD8 ratio (HR = 1.14; 95% CI = 1.00–1.31; p = 0.04) had negative independent prognostic impacts on MCC-specific survival. This evidence concerns the gene CD8A and Merkel cell skin cancer.