Urinary excretion of the cancer-related glycoprotein EDCl: effect of chemotherapy.

The effect of chemotherapy on the urinary excretion of a cancer-related glycoprotein labeled EDCl, recently isolated from the urine of a patient with acute myelocytic leukemia, has been studied by radioimmunoassay in eight cancer patients who were excreting 200 to 500 mg/day before treatment. In five patients, chemotherapy caused marked clinical improvement, and the glycoprotein disappeared from the urine within 10 days after chemotherapy began. In the two patients with solid tumor who responded to chemotherapy, disappearance of glycoprotein EDCl from the urine preceded clinical improvement by 1 to 2 months. Four of the five responsive patients relapsed within 6 months; in each instance, the glycoprotein reappeared in the urine (greater than 100 mg/day) 2 to 5 weeks before clinical relapse. Three patients were resistant to chemotherapy, and their urinary glycoprotein did not decline during chemotherapy. Measurement of urinary glycoprotein EDCl will be useful in rapidly ascertaining which drug will be effective in a cancer patient and in predicting relapse.