EBMT 2018 | Efficacy of allogeneic stem cell transplantation in amyloidosis patients

The MM Hub were delighted to attend the 44^th Annual Meeting of the European Society for Blood and Marrow Transplantation held in Lisbon, Portugal, from 18–21 March 2018. On Monday 19 March 2018 the oral abstract session 4 was held. The session was moderated by Catarina Geraldes, from the University of Coimbra, Portugal and Tamás Masszi, from Semmelweis University, Budapest, Hungary.

The third talk of this session was given by Stefan Schönland, from the University of Heidelberg, Heidelberg, Germany, who presented an abstract entitled: Improved survival after allogeneic stem cell transplantation for light chain amyloidosis: a retrospective analysis in 55 patients of the chronic malignancy working party (EBMT). This was a non-interventional clinical study (NIS) within ProMISe.

Patients characteristics:

• N =55 pts; that underwent transplant between 1987 and 2015; 29 male pts
• Dominant amyloid organ involvement = kidney, heart and soft-tissue
• Median interval from first diagnosis to allo-SCT = 21 months
• Line of therapy for allogeneic stem-cell transplantation (allo-SCT): First = 22 pts; Second = 30 pts; Third = 3 pts
• Stem cell source: Peripheral blood (PB) = 42 pts; Bone Marrow (BM) = 12; Cord Blood (CB) = 1 pt
• Conditioning regimen: myeloablative = 12 pts; total body irradiation (TBI) = 32 pts (mostly 2 Gy); anti-thymocyte globulin (ATG) = 11 pts; campath = 3 pts
• HLA matching: syngeneic = 7 pts; matched relative = 34 pts; mismatched relative = 2 pts; matched unrelated = 11 pts; mismatched unrelated = 1 pt
• Median karnofsky index = 90% (50–100)
• Median age = 51 years (30–67)
• Serum creatinine = 91 μmol/l (52–902)

Key Findings:

• Median interval:
  • Between allo-SCT and neutrophils > 0.5 = 16 days (6–29)
  • Between allo-SCT and platelets > 50 = 15 days (1–76)
• Acute graft versus host disease (aGvHD) grade 2-4: n = 11 pts; median interval = 1.1 months from allo-SCT (0.5–3.2);
• Chronic GvHD (cGvHD): n = 17 pts; extensive in 12; median interval = 6 months (3–50)
• Complete remission (CR) = 28 pts; median interval from allo-SCT = 6 months
• Relapse = 17 pts; median interval = 8 months (1–155)
• Median follow-up = 73 months (0–286)
• Median overall survival (OS) = 44 months
  • 1-year survival = 68% (95% CI; 57–82)
  • 10-year survival = 44% (95% CI; 32–61)
• At last follow-up:
  • No of pts alive = 25/55 (4/7 syngeneic with OS plateau at 57%)
  •  Median follow-up = 73 months (0–286)
  • CR = 16 pts
• Median OS (pts who were given a transplant after 2006 vs pts given a transplant before 2006) = not reached vs 21 months, P = 0.006 (63% plateau beginning at 70 months)

This study presents findings from the largest cohort of AL patients treated with allo-SCT. Allo-SCT showed feasibility and efficacy in selected AL patients, with a decrease in early mortality and long term survival.  These findings confirm the beneficial use of allo-SCT with an HLA-identical donor in heavily pretreated young and fit MM patients with AL.