Safety of autologous hematopoietic stem cell transplantation in patients with multiple myeloma and chronic renal failure

Patients with multiple myeloma (MM) and chronic renal failure have generally been excluded from myeloablative therapy programs followed by hematopoietic stem cell support because of the potential increase in transplant-related morbidity and mortality. We here report our experience treating six MM patients with moderate to severe renal insufficiency, with autologous stem cell transplantation. One of these patients required chronic hemodialysis since the diagnosis of MM was made. Peripheral blood stem cell collection was performed with either cyclophosphamide 5.5-7 g/m2 + G-CSF, 5 microg/kg/day (patients 1-3, 5 and 6) or G-CSF, 15 microg/kg/day alone (patient No. 4). Four patients (Nos 1-4) received autotransplant as front-line therapy, while the last two patients were treated in relapse, which occurred following prior autologous stem cell transplantation in support of melphalan, 200 mg/m2 (No. 5) or maintainance therapy with alpha-interferon (No. 6). High-dose chemotherapy administered as preparation to transplant included busulfan 12 mg/kg + melphalan 80 mg/m2 (patients 1-3 and 6) or melphalan 80 mg/m2 alone (patients 4 and 5) in order to reduce mucosal damage. Following transplant, prompt and sustained recovery of hematopoiesis was documented in all the patients; 500 PMN/microI and 20000 platelets/microI were reached after a median of 13 and 14 days, respectively. None of the patients suffered from WHO grade 3-4 infectious complications. Transplant-related toxicity included grade 3-4 oral mucositis (patients 1, 4 and 5) and veno-occlusive disease (patient No. 3). Renal function either improved or remained stable throughout the transplant period. All the patients but one responded to therapy, three of them are progression free after 2, 15 and 26 months; two relapsed after 16 and 4 months and one died from cholangiocarcinoma 7 months after transplant, while still in remission. Although our experience is limited so far, these results appear promising and support the investigational use of myeloablative therapy in MM patients with chronic renal failure.