PPP4C levels had certain diagnostic accuracy in adrenocortical carcinoma (ACC), lymphoid neoplasm diffuse large B-cell lymphoma (DLBC), ESCA, HNSC, KIRC, KIRP, LIHC, lung adenocarcinoma (LUAD), LUSC, prostate adenocarcinoma (PRAD), skin cutaneous melanoma (SKCM), PCPG, THCA, and thymoma (THYM) for tumor diagnoses. This evidence concerns the gene PPP4C and cutaneous melanoma.