Prednisolone or Dexamethasone Combined With Chemotherapy in Treating Young Patients With Newly Diagnosed Lymphoblastic Lymphoma

RATIONALE: Drugs used in chemotherapy, such as prednisolone and dexamethasone, work in different ways to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. Giving more than one drug (combination chemotherapy) may kill more cancer cells. It is not yet known whether prednisolone is more effective than dexamethasone when given together with combination chemotherapy in treating lymphoblastic lymphoma. PURPOSE: This phase III randomized clinical trial is studying prednisolone to see how well it works compared to dexamethasone when given together with combination chemotherapy in treating young patients with newly diagnosed lymphoblastic lymphoma.