[Clinical evaluation of serum TAC-41 in various digestive cancers]

Tumor associated carbohydrate antigen TAC-41 identified by the monoclonal antibody against a gastric adenocarcinoma cell line. We evaluated the serum levels of TAC-41 in 55 patients with various malignancies and 44 patients with benign diseases, and compared them with the serum levels of other tumor markers including CA 19-9 and CA-50. When the normal range of serum TAC-41 level was less than 40 dilution titer, the positive rate for malignancies of TAC-41 was 100% in pancreas cancer, 80% in biliary tract cancer and 87% in hepatocellular carcinoma. On the other hand, specificity (64%) of TAC-41 in all patients was less than that of other tumor markers. However, efficiency (68%) of TAC-41 was no less than those of other tumor markers. Comparison of the serum levels of TAC-41 with CA 19-9 or CA-50 in the same samples revealed a highly positive correlation (r = 0.891) in patients with various cancers. These results indicate that TAC-41 is clinically no less useful than CA 19-9 or CA-50 as a tumor marker. The usefulness of this method is characterized by its short turnaround time and lower cost than other tumor markers. Eventually, TAC-41 is one of the most useful tumor marker in mass screening for digestive malignant diseases.