For PTGS2 rs20417, sensitivity analyses indicated that inclusion of the independent studies by Barry et al. [9], Gong et al. [10], and Ulrich et al. [15] was responsible for the significant difference observed in the risk of cancer development between NSAID users and non-NSAID users homozygous for the major allele in the colon cancer subgroup. The gene discussed is PTGS2; the disease is malignant colon neoplasm.