Clinical Significance of CA-50 Testing, July 9, 1997

Clinical Significance of CA-50 Testing, July 9, 1997

This test uses radioimmunoassay to measure a monoclonal antibody specific to malignant tumors of the digestive system. The antigen recognized by this antibody is called CA-50. Colon cancer has a 70% positive rate, liver cancer 62%, and pancreatic cancer as high as 79%. In 1988, Chen Zhizhou analyzed 258 cancer patients, finding that pancreatic cancer had the highest positive rate at 94.4%, followed by liver cancer, ovarian cancer, and prostate cancer. Additionally, CA-50 shows a 90% positive rate in malignant pleural effusion and almost 0% in benign pleural effusion. The positive rates reported in this group are as follows: pancreatic and gallbladder cancers 94.4%; ovarian and uterine cancers 88.5%; liver cancer 88.2%; malignant pleural effusion 80%; rectal cancer 77.8%; gastric cancer 68%; lung cancer 66.6%. The most valuable aspect of this test is that only 6% of healthy individuals show a positive result.