The levels of alpha 1-antitrypsin and alpha 1-antichymotrypsin in the sera of patients with gastrointestinal cancers during diagnosis.

Protease inhibitors, such as alpha 1-antitrypsin (A1AT) and alpha 1-antichymotrypsin (A1AChy) have been considered in searching for new biochemical tumor markers useful at initial diagnosis, staging, and monitoring of cancer diseases after surgery. Levels of both antiproteases in serum of 32 patients with gastric cancer and 61 patients with colorectal cancer at initial diagnosis were studied. A significant increase of A1AT and A1AChy was found in the initial stages of both cancer groups as compared to healthy blood donors. A significant correlation between A1AT and A1AChy serum level and cancer stages was observed. The antiprotease serum concentrations progressively increased with increasing severity of gastric and colorectal cancers. The A1AChy level correlated with the histologic grade of both cancers and were higher in Grade III than in Grade II. These findings could be useful in the early diagnosis of gastric and colorectal cancers and in complex preoperative diagnostic procedure to estimate the stage of disease.