The serum folate and serum vitamin B12 levels were determined in a large number of patients with malignant hemotologic diseases. Low values of folate were noted mostly in patients with active disease, whereas the majority of cases in complete remission or with mild disease had normal values. No such correlation between the status of disease and serum vitamin B12 levels was found. In chronic myelocytic leukemia the number of white blood cells is inversely proportional to the folate level. Serum folate determinations may prove helpful in predicting response to daily p.o. antifol therapy in most patients.
This study was aided in part by USPHS Grants CA-04457, AM-09062, and AM-04971 and in part by the Albert A. List, Frederick Macklin, and Anna Ruth Lowenberg Funds.