Outcomes of bortezomib combination chemotherapies in autologous stem cell transplantation-ineligible patients with AL amyloidosis

Background Treatment protocols for light chain (AL) amyloidosis have been derived from myeloma treatment. Bortezomib is a key drug used for the treatment of myeloma and AL amyloidosis. We retrospectively investigated the efficacy and toxicity of bortezomib-based chemotherapy in patients with newly diagnosed AL amyloidosis. Methods We reviewed the outcomes of newly diagnosed autologous stem cell transplantation (auto-SCT)-ineligible AL amyloidosis patients who received bortezomib-based chemotherapy at a referral center between 2011 and 2017. Results Of 63 patients who received bortezomib-based chemotherapy, 32 were male, and the median age was 66 years (range, 42. 82 yr). The hematologic overall response rate (ORR) was 65.1%, and the chemotherapy regimen with the best hematologic response was VMP (75.7%, 28/37). Sixty patients had significant organ (heart or kidney) involvement; 28.3% of patients (N=17) had major organ responses after chemotherapy. With a median follow-up of 34 months, there was no significant difference in progression-free survival ( P= 0.49) or overall survival ( P =0.67) according to regimen. Most hematologic and non-hematologic problems were manageable. Conclusion Various chemotherapy combinations based on bortezomib are currently employed in the clinical setting, but no difference was found in terms of efficacy or toxicity.