ABSTRACT
The clinical value of circulating prolactin as a marker for the diagnosis of primary breast cancer compared with other serum markers was evaluated in Thai women. Forty women with primary breast cancer, 20 women with benign breast disease and 20 normal women were included in the study. Single serum levels of prolactin, CEA, CA 15-3, MCA and c-erbB-2 were simultaneously measured. At 95% specificity, prolactin gave the highest diagnostic sensitivity (92.5%) compared with a sensitivity of 10-30% obtained from the other markers studied but did not correlate with any of them. Concentrations of CEA, CA 15-3, MCA and c-erbB-2 in 40 breast cancer tissue were related to each other by multiple regression analysis and they also showed good positive and negative agreement among subjects. Thus, measurement of a single marker among four of them should be economically and clinically appropriate. CEA when compared with other markers, showed a better relationship with clinicopathological parameters e.g. tumor diameter and axillary lymph node involvement. This preliminary study suggests that prolactin and CEA may be a good combination of paired serum markers for the early detection of breast cancer. A prospective study should be performed in order to demonstrate the exact relationship of elevated blood prolactin levels and the risk of breast cancer in the Thai population.