Allogeneic Hematopoietic Cell Transplantation for Multiple Myeloma.

Allogeneic hematopoietic cell transplantation (allo HCT) is a potentially curative therapy for multiple myeloma (MM), but has high treatment-mortality (TRM). In addition, disease relapse occurs in a significant number of patients. We sought to evaluate if the recent advances in the field of HCT and MM have impacted the results of allo HCT for MM. We present the results of allo HCT performed at a single center over last 25 years.

149 patients with MM who underwent allo HCT between 11/1985 and 6/2010 using myeloablative (MA) N= 52, or reduced intensity conditioning (RIC) N=97 at our institution were retrospectively analyzed.

Patient characteristics and pertinent outcomes are summarized in the Table. 62 (42%) were female. Median age was 50 (28-70) years. Median follow up is 2.4 years [11.3 years for the patients who received allo HCT prior to year 2000(<2000); 2 years for the patients who received allo HCT in the year 2000 and onwards (≥2000)]. TRM at 2 year was 37%. TRM was significantly lower for year ≥2000, recipients of RIC regimens, recipients of peripheral blood stem cells (HPC-A), and disease status at transplant PR or better. There was no difference between TRM for patients above or below age 50 years (p 0.08). Grade II-IV acute and limited or extensive chronic graft-versus host disease was seen in 31%, and 37% patients, respectively. Progression free survival (PFS) at 2 year and 5 year was 23% (95% CI: 16–30) and 15% (95% CI: 9–21), respectively. Overall survival (OS) at 2 year and 5 year was 40% (95% CI: 32–48) and 21% (95% CI: 13–29), respectively. At the time of last follow up 40 patients are still alive and 28 are in remissionn, longest for 166 months. On univariate analysis the OS was significantly better for year ≥2000 versus year <2000; recipients of HPC-A versus HPC-M; primary responsive disease versus relapse or primary refractory disease at HCT; disease status at HCT PR or better; and patients without poor risk cytogenetic features at diagnosis. OS was longer in patients who received maintenance therapy post allo HCT (N=12) versus the patients who did not, although it did not reach statistical significance (2.9 years versus 8.4 months; p 0.06).

Allo HCT for MM can offer long term disease control in a subset of MM patients. TRM has declined and outcomes have significantly improved over the last decade. Maintenance therapy may have a role post allo HCT.

Shah:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Research Funding. Weber:novartis-unpaid consultant: Consultancy; Merck- unpaid consultant: Consultancy; celgene- none for at least 2 years: Honoraria; millenium-none for 2 years: Honoraria; celgene, Millenium, Merck: Research Funding. Qazilbash:Celgene: Speakers Bureau.