Biological changes in serum antiproteases as related to tumor progression.

The two major antiproteases (alpha-1-antitrypsin and alpha-2-macroglobulin) were studied in the serum of cancer patients (273 and 103 subjects, respectively) and in a control group. In cancer patients, the values were stratified by clinical stage (local, loco-regional and metastatic disease). Serum alpha-1-antitrypsin was different in normal people (341 +/- 110.7 mg/dl) than in every cancer group (p less than 0.0005). The behavior of alpha-2-macroglobulin was similar, with significant differences (p less than 0.0005) between normal people (317.6 +/- 105.4 mg/dl) and the cancer groups. Serum alpha-1-antitrypsin was different in local, loco-regional and metastatic disease; however, alpha-2-macroglobulin did not show these differences. In metastatic disease, sensitivity was 96.66% for alpha-1-antitrypsin and 94.79% for alpha-2-macroglobulin.