Evaluation of serum laminin as a tumor marker in breast cancer

Laminin is a noncollagenous constituent of the extracellular matrix (baseme nt membrane). Increased serum concentrations were recorded in patients with a variety of cancers. The clinical usefulness of serum laminin as a marker for breast cancer was investigated in 60 female patients with malignant br east tumors (30 metastatic, 30 nonmetastatic). Subjectively healthy age-mat ched women (n=30) served as a control group. Laminin was significantly high er in breast cancer patients than in normal controls. Serum laminin levels were also significantly higher in patients with metastasis than in those wi thout metastasis. A positive correlation was observed between serum laminin and the breast cancer-associated antigen CA 15-3 in the tumor patients. Th e sensitivity and specificity values of laminin for cancer detection at the optimum decision level [mean+2 SD (1.4 U/ml)] were 75% and 97% respectivel y, with a 98% positive predictive value, 66% negative predictive value, and 82% diagnostic efficiency. For the detection of metastasis, serum laminin exhibited 77% sensitivity and 100% specificity [best decision level: mean+2 SD (1.9 U/ml)], with a 100% positive predictive value, 81% negative predic tive value, and 88% diagnostic efficiency. The latter specificity and posit ive predictive value were superior to those obtained with serum CA 15-3. Th ese results suggest that serum determination of laminin could be a useful d iagnostic tool in breast cancer and a valuable parameter in the prediction of metastasis.