Between 1985 and 1996, 51 patients with relapsed or refractory small cleaved cell lymphoma (SCCL) received high-dose chemotherapy +/- TBI in conjunction with autologous (ABMT) (36 patients) or allogeneic transplantation (15 patients). Patients were eligible for ABMT if the bone marrow biopsy done prior to the planned transplant did not reveal microscopic involvement with SCCL. Patients receiving ABMT had a median age of 48 years, had received a median of 2.5 chemotherapy regimens prior to transplantation, and were transplanted a median of 35.5 months from diagnosis. Among patients receiving ABMT, 5 year actuarial survival was 56+/-11%. Median survival was 126+ months, and median survival from diagnosis was 191 months. Univariate and multivariate analysis identified sensitive disease as the best predictor of a favorable response. Five-year actuarial survival was 66+/-12% for patients with sensitive disease at the time of transplant as compared to 29+/-17% for patients with resistant disease, P = 0.015. Median survival in patients with sensitive disease at the time of ABMT was 126+ months. By univariate analysis, survival was significantly better for patients receiving ABMT as compared to patients receiving allogeneic transplants. Median survival following allogeneic transplantation was 5 months; 5 year actuarial survival was 15+/-13%. In a multivariate analysis, which considered autologous vs allogeneic transplantation, sensitive vs resistant disease, <3 vs > or = 3 prior treatments, and prior bone marrow involvement, allogeneic transplantation was significantly associated with poor survival. Treatment-related mortality occurred in eight of 15 patients receiving allogeneic transplantation and limited the effectiveness of this therapy. High-dose therapy in conjunction with ABMT is effective therapy for patients with SCCL whose disease is sensitive to chemotherapy and whose marrows are microscopically free of disease. Because of possible selection bias, it has not been proven that this approach increases survival in these patients. Treatment-related mortality limits the effectiveness of allogeneic transplantation in SCCL.