[Determination of plasminogen activator of the head and neck tumor tissue].

Fibrin plate was used to determine plasminogen activator (PA) of the head and neck tumor tissue. The results revealed: 1. The specific activity of PA of primary malignant tumor and neck lymphatic metastatic nodes were higher than that of normal tissue near cancer and benign tumor tissue; 2. The specific activity of PA was enhanced as advance of tumors in clinical stage. This study implicated that PA released from cancer cells can catalyze and convert plasminogen to plasmin, which results in tissue degradation, invasion and metastasis of tumor.