Variations in serum alkaline DNase activity: a possible clinical test for therapeutic prognosis of human tumors.

Previously published histochemical observations indicated that variations in serum alkaline DNase activity (SADA) could be considered as a possible prognostic test for human tumor therapy. In more than 80 cancer patients biochemical measurements of SADA were performed using the spectrophotometrical technique. A decrease of SADA promptly after the beginning of tumor treatment (phase I) may be interpreted as an early sign of therapeutically induced tumor necrosis and as a positive response to the treatment. A delayed regain of SADA (phase II) can predict the long term evolution of the disease. In this phase (II), a regain of SADA up to values higher than the initial value corresponds to a complete tumor regression. If the regain is limited to values lower than the initial value, only a partial tumor regression is seen. No variations of SADA were observed in patients without therapeutic response and with fatal evolution.