Adolescent Adult Antineoplastic Combined Chemotherapy Protocols--therapeutic use Asparaginase--therapeutic use Burkitt Lymphoma--drug therapy Cyclophosphamide--therapeutic use Daunorubicin--therapeutic use Disease Progression Dose-Response Relationship, Drug Doxorubicin--therapeutic use Female Follow-Up Studies Humans Male Mercaptopurine--therapeutic use Methotrexate--therapeutic use Middle Aged Prednisolone--therapeutic use Prednisone--therapeutic use Retrospective Studies Severity of Illness Index Time Factors Treatment Outcome Trimethoprim, Sulfamethoxazole Drug Combination--therapeutic use Vincristine--therapeutic use