“…Among these, Hepar-1 constitutes a reference point, with a sensitivity and specificity index that is 82% to 95% [5], but in recent years Arginase-1 (Arg-1) and Glypicane-3 (Gly-3+) have also acquired a certain role [6]. Isa et al [5] describe in detail that to be considered effectively positive, the immunohistochemical staining must be strong, cytoplasmic, and granular in spite of a small part of malignant neoplasms that can focal, in an aberrant sense, express it. Briefly, all this serves to allow a correct differential diagnosis with respect to primary malignant skin neoplasms (such as squamous cell carcinoma, melanoma and adnexal cutaneous neoplasm) and secondary non-hepatic skin neoplasms originating from organs such as lung, gastrointestinal tract, kidney, bladder, prostate, adrenal carcinoma and/or pancreatic carcinoids [5,6,[14][15][16][17][18][19].…”