Lymphoblastic lymphoma in children - A randomized trial comparing LSA₂-L₂ with the A-COP+ therapeutic regimen: A Pediatric Oncology Group study

From May 1979 to March 1983, 76 evaluable patients with lymphoblastic lymphoma (LBL) were treated by members of the Pediatric Oncology Group (POG). Forty-six children treated by the six-drug A-COP+ regimen (Adriamycin [doxorubicin; Adria Laboratories, Columbus, OH], vincristine, prednisone, cyclophosphamide, methotrexate, and hydrocortisone) were compared in a prospective randomized trial with 30 patients receiving the modified ten-drug LSA₂-L₂ (cyclophosphamide, vincristine, methotrexate, Daunomycin [daunorubicin cerubidine; Wyeth Laboratories, Philadelphia], prednisone, cytarabine, thioguanine, asparaginase, hydroxyurea, and carmustine) regimen. After adjusting for stage (I and II v III v IV), there was no statistically significant difference (P = .19) between A-COP+ and LSA₂-L₂ regimens on the basis of 3-year survival and disease-free survival (62% v 72% and 53% v 58%, respectively for the two treatment regimens) but the power of analysis and thus the ability to detect a clinically meaningful difference in the outcome with the two regimens was limited by the small number of patients. Neither therapy was effective for most patients with stage IV disease, with failure occurring in six of seven children receiving A-COP+ regimen and eight of 11 patients receiving LSA₂-L₂. Although the LSA₂-L₂ regimen was more toxic during the induction of remission, the toxicity during maintenance was acceptable and similar for both treatments. CNS relapse was not a significant problem whether cranial radiation with intrathecal (IT) therapy (A-COP+) or IT therapy alone (LSA₂-L₂) were used. Our results confirm the overall effectiveness of the LSA₂-L₂ regimen in children with LBLs, especially those initially free of bone marrow or CNS involvement, but were inconclusive to as the inferiority or superiority of this regimen over the A-COP+ regimen.