Intermediate dose methotrexate (IDM) in childhood acute lymphocytic leukemia (ALL).

We employed three courses of intermediate dose Methotrexate (IDM) added onto a standard induction and maintenance program with the concept of both central nervous system (CNS) prophylaxis and simultaneous systemic intensification. Cranial radiation (RT) was not employed as CNS prophylaxis. Fifty of 52 patients (to age 18) achieved complete remission. Time on study now ranges from 22-68 months with a median time of 33 months. We separated the children into standard risk and increased risk. We defined increased risk as a WBC over 30 000/mm3 at presentation and an age of less than two years or greater than 10 years at presentation. There have been 15 relapses on these 50 patients; 11 occurred in increased risk patients (of 22 increased risk patients) and four occurred in standard risk patients (of 28 standard risk patients). There were seven CNS relapses, six systemic relapses, one simultaneous systemic and CNS relapse and one testicular relapse. Toxicity to the IDM was small with the worst problem being mucositis. No leukoencephalopathy occurred. The control of hematological relapse is excellent and the avoidance of potential long-term complications notes is even of greater importance.