IL1RAP and Merkel cell skin cancer: Associations of IL-33, ST2/IL1RL1, IL1RAcP expression, clinicopathological factors (size, sex, age, stage [1 and 2 vs. 3 and 4], LT expression, presence of MCPyV DNA), and survival was investigated further with tissue microarray in a series of 138 MCC patient samples (Figure 11).