T h e immunosuppressive activity of various anticancer drugs has been evaluated by its effect on skin homograft survival in 45 patients. Patients with no evident advanced malignant disease and cancer patients receiving no therapy showed a mean skin homograft survival time of 8 days. Among the various types of anticancer therapy utilized, the drugs AB 132, hydroxyurea, mitomycin C and methotrexate with folinic acid each gave a significant prolongation of skin homograft survival. Neither the degree of drug toxicity nor difference in blood type or sex significantly altered the skin homograft survival under this study.
NTICANCER DRUGS HAVE A V A R l h n L E DECREE
A of immunosuppressive activity23 $1. ' 2 antl they have been utilized to lower immunological defenses ag-ainst homotransplantation; the suppression of renal and hematopoetic homograft rejection thus has been achievetl.1" 14
T h e immunological effects 01 these drugs have led to their use in various autoimmune and collagen diseases.". 7 % * During cancer chemotherapy the drugs act at the cellular level against both the tumor cells and against certain rapidly divitling normal cells of the patient. With the skin homograft survival time it was possible to test another, frequently poorly understood action of the anticancer drug-its immunosuppressive activity in the pa tien t.
MATERIAI. AND METHOD
T h e adult patients in this study were in the hospital for treatment of cancer or other diseases. There were 26 women and 24 men, ages ranging from 23 to 80 years, with an average age of 56 years.
Skin homograft survival time in patients without evident malignant disease was determined by performing skin homografts in 3 patients, one of whom had been treated by x-ray therapy lor in situ carcinoma of the intrinsic larynx 6 months previously. This man was still free or disease 2 years later. T h e second patient had a benign radiation ulcer