Serum human a-lactalbumin as a marker for breast cancer

Abstract

Serum levels of α-lactalbumin were assayed using a monoclonal antibody specific for this breast specific molecule. Elevated levels were found in 87% (48/55) of sera from women in the third trimester of pregnancy (29.1 ± 7.4ngml -1), from 64% (62/97) of patients with breast cancer (23.4 ± 5.6 ng ml-1), and from 70% (56/80) of patients with gynaecological cancers (19.4 ± 6.7 ng ml-1). These α-lactalbumin levels were significantly higher (P< 0.001) than those for men and non-pregnant women (11.0 ± 2.3 ng ml-1) and for patients with other, non-gynaecological cancers (13.4 ± 3.6ngml-1). The α-lactalbumin levels were higher in patients with stage IV breast cancer than those with stage I-III breast cancer. The overall sensitivity and specificity of the radioimmunoassay were 72% and 75% respectively. These findings suggest that the assessment of serum levels of α-lactalbumin may be useful as a marker for monitoring breast cancer. © The MacMillan Press Ltd., 1990.