To assess whether CDCP1 protein is expressed at elevated levels in cancer tissues and examine inter- and intra-patient variability, we performed immunohistochemical staining of tissue microarrays containing 70 bladder carcinomas, 35 invasive breast carcinomas, 36 colon adenocarcinomas, 109 lung carcinomas, 35 PDACs, and 37 prostate adenocarcinomas. This evidence concerns the gene CDCP1 and cancer.