CDKN2A and neoplasm: Because CpG island promoter methylation is a common feature of OC [8], we performed a multiplex methylation‐specific PCR on a panel of 8 gene promoters known to be methylated in GI cancers, CDKN2A, CHFR, MGMT, MLH1, NDRG4, RASSF1, RUNX3 and TFPI2, on 105 formalin‐fixed paraffin‐embedded tumour samples, among which 85 OACs and 20 OSCCs.