Toxicity of a second autologous peripheral blood stem cell transplant in patients with relapsed or recurrent multiple myeloma.

Toxicity associated with a second autologous peripheral blood stem cell transplant (APBSCT) in patients who relapse following initial APBSCT for multiple myeloma (MM) has not been well described. We conducted a retrospective, case-series of 25 consecutive patients who received a second APBSCT for relapsed or progressive disease following prior APBSCT to describe associated toxicity. Grade 3 or 4 toxicities were observed in 92% of patients after each APBSCT. More patients developed an elevated serum creatinine (4%vs. 36%; p = 0.011) following the second APBSCT. Median time to neutrophil engraftment was 10 days following both transplants (p = 0.428). Platelet engraftment was delayed by 2 days after the second APBSCT (median 12 vs.14 days; p < 0.025). There were two deaths before day 100. In conclusion, patients who undergo a second APBSCT for relapsed MM experience more nephrotoxicity. Delayed platelet engraftment and an 8% treatment-related mortality were observed following the second APBSCT.