[Cysteine cathepsins secreted into the blood as markers of tumor growth].

Cathepsin H was secreted into the blood plasma of cancer patients before and after surgery. In the mandibular osteoradionecrosis group, there was a tendency for cathepsin H level to decrease, although only in cases free from recurrent tumor growth. Constant levels of cathepsin H were maintained after specific treatment, even in tumor recurrence-free cases. Secretion of such enzymes may be considered a characteristic of tumor-bearing organism. Biochemical assay of cathepsin H level may be used as another procedure for diagnosing different patterns of malignant growth.