RASSF1 and head and neck squamous cell carcinoma: These results are in accordance to the study of Dong et al who reported of RASSF1A methylation in 15% of primary HNSCC and higher frequency in cell lines (32) and to Hogg et al who reported of 17% RASSF1A methylation in HNSCC while poorly differentiated HNSCC were more commonly methylated for RASSF1A than moderately and well differentiated HNSCC (8).