The sensitivity and specificity of monoclonal antibodies URO-2 and 19-9 in the immunohistochemical classification of primary adenocarcinomas1
The specificity and sensitivity of commercially available monoclonal antibodies (McAb) to tumor antigens were tested using McAb 19-9, derived from a colorectal adenocarcinoma, and URO-2, derived from a renal adenocarcinoma. Using the avidin-biotin-complex technique and frozen tissue, 53 adenocarcinomas representing lung, breast, colorectal, ovarian, renal, and uterine origin were studied. All slides were randomized and subsequently evaluated for staining intensity and percent tumor-area positivity. The sensitivity and specificity of 19-9 for colorectal adenocarcinoma were 74% and 54%, respectively. The sensitivity and specificity of URO-2 for renal adenocarcinoma were 100% and 87.5%, respectively. In most cases, URO-2 stained greater than 75% of the renal tumor area; however, 19-9 stained less than 50% of the colorectal tumor area.