As a weak expression of KIF20A in the normal thymus in addition to the testis was observed in the cDNA microarray and RT–PCR analyses, KIF20A is not a perfect cancer/testis antigen but a TAA overexpressed in pancreatic cancer, as well as in bladder cancer, non-small cell lung cancer, and cholangiocellular carcinoma. This evidence concerns the gene KIF20A and cholangiocarcinoma.