PIK3CA and melanoma: The High UV CSD includes two melanoma subtypes: Lentigo maligna melanoma (Category II), with mutations in NRAS, BRAF-nonV600E, KIT, TERT, CDKN2A, PTEN or TP53; and Desmoplastic melanomas (Category III) with mutations in NRAS, PIK3CA, NFKBIE or NF1.