Comparison of two consecutive trials for treatment of childhood non-Hodgkin's lymphoma.
Two consecutive trials for the treatment of childhood non-Hodgkin's lymphoma were evaluated, carried out by the same cooperative groups. Group A: From June, 1973 to December, 1975, 50 evaluable patients under 16 years of age participated in a study that included vincristine and prednisone plus surgery and/or radiotherapy as induction. This was followed by 2400 rad of cranial radiotherapy plus 5 doses of intrathecal methotrexate-dexamethasone and anti-leukemia (6-mercaptopurine, methotrexate, cyclophosphamide) or anti-lymphoma (cyclophosphamide, vincristine, procarbazine, and prednisone) maintenance treatment. Group B: From January, 1976 to December, 1980, 55 evaluable patients participated in a consecutive study that added Adriamycin (doxorubicin) and cyclophosphamide to the former induction regimen. Central nervous system (CNS) prevention was performed with 5 doses of intrathecal methotrexate-dexamethasone. Maintenance treatment was the same. Prognostic factors as stage and primary site were comparable in both groups. A total of 33 (66%) of 50 children of Group A and 48 (87%) of 55 children of Group B achieved complete remission (P less than 0.005). Disease-free survival at 60 months was 27% in Group A and 49% in Group B; for Stage I-II, 30% in Group A and 85% in Group B (P less than 0.025); for Stage III-IV 28% in Group A and 36% in Group B (not significant). In Group A, 9.1% and in Group B, 8.3% had primary CNS relapse. Both maintenance schedules had the same relapse rate. It was concluded that: (1) the addition of Adriamycin and cyclophosphamide to vincristine-prednisone in Group B produces a higher rate of complete remission in Stage III-IV, a higher rate of disease-free survival in Stage I-II, and a higher survival rate in all stages; (2) CNS prevention with intrathecal methotrexate-dexamethasone is equally effective as cranial radiation plus intrathecal methotrexate-dexamethasone; and (3) anti-leukemia and anti-lymphoma maintenance are equally effective in the context of this study.