PIK3CG mutation and amplification are frequent in multiple malignancies, including 9–11% of melanomas and uterine, stomach and squamous cell lung cancers, while genetic alterations in PIK3R5 and PIK3R6 are prevalent in uterine cancer and melanoma, occurring in 4–8% of cases [50,76,77,78,79]. The gene discussed is PIK3CG; the disease is melanoma.