Carcinoembryonic antigen and L-fucose in malignant and benign mammary disease.

A prospective study of 123 patients was undertaken to determine whether carcinoembryonic antigen (CEA) or L-fucose could be used as "tumor markers" to distinguish patients who had mammary cancer (41) from patients who had benign mammary disease (41) and patients who did not have mammary cancer (41). The predictive value of positive test results for both L-fucose and CEA was lower for patients who smoked than for those who did not. The sensitivities of CEA and L-fucose indicators are both below 55%. There were frequent false-positive and false-negative results. A substantial overlap in the levels of CEA and L-fucose was found for the patients who had mammary cancer and those who had benign mammary disease. CEA and L-fucose performed similarly in distinguishing cancer from benign disease. For patients who smoked, however, the predictive value of L-fucose was only 44%. The effect of smoking on L-fucose levels may account for discrepancies in L-fucose data reported in previous studies of mammary cancer. Neither CEA nor L-fucose were found to be of value in screening for mammary cancer.