Autologous bone marrow transplantation for high-grade lymphoid malignancy using melphalan/irradiation conditioning without marrow purging or cryopreservation. The Northern Regional Bone Marrow Transplant Group. We report the safety and efficacy of 34 consecutive autologous bone marrow transplant (ABMT) procedures performed in adult patients with high-grade lymphoid malignancy after remission induction therapy. Fifteen patients with acute lymphoblastic leukemia (ALL) and six with high-grade non-Hodgkin's lymphoma (NHL) received pretransplant conditioning with intravenous (IV) melphalan and fractionated total body irradiation (TBI). Thirteen other patients with NHL were conditioned with melphalan alone, having previously received local involved field radiotherapy. Unmanipulated noncryopreserved autologous marrow was reinfused within 48 hours of harvesting. Engraftment occurred in all patients with medians of 10 days of neutropenia (neutrophils less than 0.5 x 10(9)/L), 4-day platelet transfusion requirement, 3 U packed RBC transfusion, and 18 days in hospital posttransplant. There were no procedure-related deaths. Actuarial disease-free survival in the 13 patients with ALL receiving autotransplant early in first remission is 48% with a median follow-up of 3 years. Two other ALL patients who had autotransplants after a period of maintenance therapy also remain in complete remission (CR). These results compare favorably with our 34% disease-free survival (DFS) in 15 allogeneic ALL transplant patients and 21% DFS in 19 patients on standard maintenance after a common induction schedule. No relapses have occurred in the 17 NHL patients transplanted in remission (median follow-up 2 years), but the two NHL patients who developed recurrent disease before ABMT died of progressive disease after temporary responses. We conclude that this method of ABMT results in rapid reengraftment with lack of toxicity and that the conditioning treatment used shows good efficacy against disease. It is applicable in high-grade lymphoid malignancy in first remission, and our results call into question the need for marrow purging in ALL and NHL patients transplanted in first remission. 