Collection of peripheral blood stem cells after a preceding autograft: unfavorable effect of prior interferon-alpha therapy

Eighty-eight previously autografted (78 transplanted twice and 10 once) mye loma patients who had no cryopreserved stem cells available for possible fu ture use received G-CSF for mobilization of stem cells. One-fourth of the p atients had progressive disease at the time of apheresis, All patients had received 200 mg/m(2) melphalan for the first transplant. The interval betwe en the preceding transplant and the harvest was 5-68 months (median 29), A total of 0.46-9.16 (median 3.03) x 10(6) CD34(+) cells/kg were collected. M ore than 2 x 10(6)/kg CD34(+) cells were collected in 76% of the patients, and greater than or equal to 5 x 10(6)/kg in 14%, On multivariate analysis, patients with platelet counts of greater than or equal to 200 x 10(9)/l (P < 0.0001), those who had not received any myelosuppressive chemotherapy be tween the last transplant and the collection (P = 0.02), and those who had received interferon-alpha for less than or equal to 6 months (P = 0.03) had better collections. Eleven of 12 patients autografted with these cells had prompt neutrophil recovery (median 10 days to 0.5 x 10(9)/l) but recovery to 50 x 10(9)/l platelets was delayed or incomplete in 11 of 12, We conclud e that it is possible to harvest peripheral blood stem cells with G-CSF sti mulation in patients who have been autografted previously. Limited data sug gest that platelet recovery may be suboptimal when these cells are used. Th ese findings have practical implications for patients with malignant diseas es in remission after autografting who may be candidates for future salvage therapy but have no stem cells stored, and for patients with chronic myelo id leukemia who are on long-term interferon-alpha therapy to attain cytogen etic remission for eventual collection of normal stem cells.