The collagenase activities, interstitial collagenase and type IV collagenase, in human stomach cancer: with special reference to local spreading and lymph node metastasis.

In order to investigate the role of collagenase in cancer invasion and metastasis, two collagenase activities of interstitial collagenase and type IV collagen degrading enzyme (type IV collagenase) were determined in 40 cases of human stomach cancer tissue. Elevated cancers which are known to have a propensity to cause blood-borne metastases showed higher activities of both interstitial collagenase and type IV collagenase than flat or ulcerous type of cancer. Using the parameters of lymph node metastasis vs tumor size or vs depth of cancerous invasion into the stomach wall, classification of the cases was attempted according to the degree of malignancy. In the cases with marked lymph node metastases in spite of small tumor size and/or shallow cancerous invasion into the stomach wall, type IV collagenase activity was higher than that in the cases with lower malignancy (p less than 0.025, p less than 0.05, respectively). These results suggest that collagenase in stomach cancer tissue play an important role in the invasion and metastasis of cancer cells. Type IV collagenase activity in stomach cancer tissue could be one of the useful biological markers for the degree of malignancy.