Expression of DNMT1 appeared to be a protective factor in patients whose tumor occurred in both sides but it is not statistically significant (OS, P = 0.139; Figure S1) (DFS, P = 0.269; Figure S1); opposite of findings from patients whose tumor occurred in single side (OS, P = 0.429; Figure S1) (DFS, P = 0.210; Figure S1). This evidence concerns the gene DNMT1 and neoplasm.