A group of 60 patients with far-advanced malignant tumors was selected for therapeutic trial of p-di-(2-chloroethyl)-aminophenylalanine. The drug was administered orally or by segmental perfusion usually in a dosage of 2 mg. per kilogram of body weight. Some patients showed no improvement, some improved for a time only to relapse later, but in some the improvement was lasting. The most marked improvement was in patients with sarcoma, particularly Hodgkin's disease, fibrosarcoma, Kaposi's sarcoma, and neurofibrosarcoma. Next in order of susceptibility to the drug were melanomas and carcinoma of the breast. Occasional cases of carcinoma of the lung, tongue, ovary and colon were susceptible but for shorter periods of time. Bone marrow depression in varying degrees was the side-effect, rarely observed with the oral administration, more frequently with the segmental perfusion.