| Abstract: |
BR27.29 is one of several carcinoma associated mucin antigens proposed as a marker in breast cancer. We evaluated the performance characteristics of the Truquant(R) BR radioimmunoassay for the quantitative measurement of BR27.29 and assessed the clinical utility of this marker in the monitoring of breast cancer. The upper limit of normal (37 U/ml) was determined from BR27.29 values (Mean + 3 SD) for 100 female subjects apparently free of disease. The sensitivity (0.17), specificity (0.97), negative predictive value (0.48), positive predictive value (0.86) and efficiency (0.53) were derived from BR27.29 data for 90 patients with benign breast disease and 111 patients with primary breast cancer. The sensitivity of BR27.29 was higher in women with stage III or IV primary breast cancer (0.63 and 0.80, respectively) or with recurrent cancer (0.67) indicating that elevated BR27.29 levels are associated predominantly with late stage disease. Abnormal BR27.29 levels also were documented in women with other types of cancer (ovarian, uterine, colon and lung), further evidence for lack of specificity. Nonetheless, BR27.29 proved reliable in the follow-up of patients with advanced disease since antigen levels correlated closely with disease regression or progression. |
