Certain morphologic features have been associated with NTRK1-fused Spitz tumors, including the filigree-like appearance of the rete ridges, lobulated nests of melanocytes with rosette-like structures, and prominent maturation of tumor cells with depth [19,25,26]; however, these features are only seen in a minority of cases and, hence, their absence does not rule out an NTRK fusion [27]. Here, NTRK1 is linked to neoplasm.