Extent of Skeletal Involvement Did Not Predict for Outcome After Autologous Stem Cell Transplant for Patients With Multiple Myeloma

Abstract

Background: Autologous stem cell transplant lengthens survival in patients with multiple myeloma, but has mortality from infections and high costs. Determination of prognostic factors predicting prolonged survival prior to transplant may help determine which patients may be better candidates for autologous SCT. Here, we hypothesized that extensive skeletal involvement prior to transplant predicted for adverse transplant outcome. Methods: Patients undergoing autologous stem cell transplants from 1999 to 2003 at Rush University Medical Center were reviewed to determine if having fewer lytic lesions prior to stem cell transplant there would lead to longer disease free survival post-transplant. Patients with less than 3 lytic lesions were compared to those with more than three lytic lesions regardless of subtype of myeloma or time to transplant. 83 patients had autoSCT at RUMC during the time frame, 12 patients did not have documented skeletal surveys and one patient underwent alloSCT, so they were not included in the analysis. Of the remaining 70, 44 patients had numerous lesions while 26 had 0-2 lesions. The mean age at SCT for both groups was 55.6 years. The various subtypes of myeloma for the group of 44 patients with numerous lesion is 25 with IgG, 6 with IgA, 1 with IgD, 5 with light chain, and 7 that were not specified, and for the group of 26 patients with 0-2 lesions, 19 were IgG, 2 IgA, 4 not specified and 1 with POEMS. The average time to transplant from diagnosis was 624 days with a range of 117-2294 for the group with 0-2 lesions, and 511 days with a range of 93-7321 days for the group with numerous lesions. Results: 28/44 patients with numerous lesions had documented disease progression with a median of 27 months from transplant, with ranges of 4-74 months, while 19/26 patients with fewer lesions progressed with median of 35 months and range of 12-75 months. Prior to August 2008, 15/44 patients in the group with numerous lesions died, while 19/26 patients in the group with fewer lesions died. Analysis with Kaplan Meyer survival curves showed no difference in disease free survival and death between the two groups, with p-values of 0.34 and 0.53 respectively. The estimated 5-year survival was 60% versus 50% for pts with 0-2 lesions versus numerous lesions respectively. Conclusions: We conclude that extent of skeletal involvement defined by number of lytic lesions does not predict for transplant outcome in patients with multiple myeloma.