The objective of this study was to determine in children with acute lym phocytic leukemia (ALL) whether prolonged remission could be attained following relapse from prior chemotherapy. Multiple agent chemotherapy and central nervous system radiotherapy were administered to 16 children who had had one or more relapses. With prednisone, vincristine, and daunomycin, 14 of 16 patients attained complete remission in a median time of 31 days. The median duration of complete remission for the 14 children was 12 months. Drug toxicity and morbidity secondary to therapy included pancytopenia, oral ulcerations, nausea, vomiting, diarrhea, abdominal pain, and potentially fatal infections. Five of the 14 who achieved remission developed Pneumocystis carinii pneumonia. Patients who had relapsed during prior unmaintained remission had superior responses to therapy. After 46 to 50 months in this study, three patients remain in continuous complete remission and two others remain in continuous hematologic remission. Therapy was stopped in four children after 36 months of continuous hematologic remission. These results suggest that children with ALL who experience relapse have an opportunity for a prolonged subsequent remission.
REQUENT PROLONGED REMISSIONS HAVE BEEN F obtained with multiple agent chemotherapy and radiotherapy in children with previously untreated ALL.13,6-8 Children who experience relapse after conventional chemotherapy would not be expected to respond as well since after the first, subsequent remissions tend to be progressively more difficult to attain and of shorter duration. However, this prediction had not been tested using multiple agent therapy following relapse. In this study, children with ALL who had relapsed at least once were given combination chemotherapy and "prophylactic" central nervous system therapy. T h e specific aim was to determine whether children who had relapsed after prior chemotherapy would experience frequency and duration of remission comparable to those observed in previously untreated children.
From the Hematology and Radiology Services, St.