CD163 and Merkel cell skin cancer: Non-melanoma skin cancers such as extramammary Paget’s disease (EMPD), cutaneous squamous cell carcinoma (cSCC) and Merkel cell carcinoma (MCC) also possess heterogeneous CD163+ TAMs that could secrete an array of cytokines and chemokines in lesional skin to regulate the tumor microenvironment [1,20,21,22].