To identify frequently mutated genes implicated in NPC, a total of 37 candidate genes (those known to be implicated in cancer pathogenesis) and 5 mutated cancer genes listed in COSMIC (EGFR, CDKN2A, PTEN, KRAS, PIK3CA), were prioritized for further assessment with an additional 88 NPC cases. The gene discussed is PTEN; the disease is cancer.