Among all cases we determined that individuals with the SULT1A1*1/*1 genotype (high activity) were most likely to present with a small tumor size (≤2 cm; OR = 2.63, CI = 1.25–5.56, P = 0.02; Table 3) compared with individuals with other SULT1A1 genotypes. This evidence concerns the gene SULT1A1 and neoplasm.