Myeloma with AL Amyloidosis: 10 Years Experience with Stem Cell Transplant.

Background: (AL) Amyloidosis is a rare and potentially fatal disease that involves deposition of light chain protein by a clonal plasma cell population. Treatment with high dose melphalan and autologous stem cell transplant (ASCT) can improve survival and reverse organ damage, but this treatment is associated with toxicity and mortality. We reviewed the outcome of patients with amyloidosis, who received hematopoietic stem cell transplant (HSCT) at our institution.

Patients and Methods: The retrospective study analyzed 32 patients with AL Amyloidosis who underwent transplant between 1997–2006. There were 17 men and 15 women, with a medium age of 53 years (range 35–73 years). All patients had diagnostic criteria for multiple myeloma (MM) and had biopsy confirmed amyloidosis of at least one organ site. Six patients had at least 1 organ involved with AL amyloidosis (3 bone marrows, 2 subcutaneous and 1 kidney), 20 patients had 2 organs involved, while 6 patients had 3 or more organs affected. All received a median of 3 cycles of chemotherapy (range 0–13) before transplant. Twenty-eight patients underwent autologous transplant, while 4 had an allogeneic transplants (2 syngeneic and 2 siblings). The preparative regimens received in 28 patients were high dose melphalan (26 autologous and 2 syngeneic), 2 patients received Busulfan and Melphalan, 2 allogeneic transplant Fludarabine and Melphalan.

Results: The median Charlson Comorbidities Index (CCI) was 3 (range 0–8). The median number of CD34+ cells infused was 4.85 x 106 cells/kg (range 1.43–7.82 cells/kg). The median time to neutrophil and platelet engraftment were 11 (range 2–21days) and 14 days (range2–41), respectively. 56% of patients developed moderate to severe gastrointestinal effects. Four patients underwent allogeneic transplant and 1 had acute and chronic graft vs host disease (GVHD). Twenty-one patients (65%) achieved a partial hematological remission (PR), and 5 patients (15%) achieved complete hematological remission (CR), with a total response hematological rate of 80%. The 100 day NRM was 3.2%. The median overall survival was (OS) 41 months (range 1–108), 7 patients died (4 relapsed and 3 infections) all 7 patients had CCI greater or equal to 4.

Conclusion: Selected patients with MM and amyloidosis can benefit from high dose therapy with stem cell support including allogeneic transplantation. The high mortality seen in patients with CCI >4 suggests that this index could be useful in selecting patients for high dose chemotherapy.