The kinetics of marrow engraftment were analyzed in 50 patients with acute leukemia (21), malignant lymphoma (15), and solid tumors (14) after high-dose multiagent chemotherapy followed by autologous bone marrow transplantation (ABMT) with nonfrozen bone marrow. Unseparated heparinized whole bone marrow was stored in 10% CPDA1 at 4 degrees C for 72 h, then filtered and reinfused. The median number of nucleated cells reinfused was 1.6 x 10(8)/kg (range 0.5-3.8 x 10(8)/kg). All patients had a full hematopoietic reconstitution. Median time to achieve a neutrophil count greater than 500/microliters was 20 days (range 12-39) and median time to achieve an unsupported platelet count greater than 20,000/microliters was 20 days (range 10-55). The main factor associated with delayed engraftment was the number of prior chemotherapy cycles. We conclude that high-dose chemotherapy with nonfrozen ABMT is a safe procedure, without the requirement for costly cryopreservation facilities.