Finally, epigenetic alterations of MMR genes, whose dysfunctions are well known to be related to genomic instability, has shown a positive correlation with the risk of MPC: Czerninski et al. demonstrated how, in their cohort of OSCC, the 100% of patients affected by multiple oral malignancies tested positive for hypermethylation of hMLH1 or hMSH2 promoters [47]. Here, MLH1 is linked to cancer.