The Challenges in Chemotherapy and Stem Cell Transplantation for Light-Chain Amyloidosis

Light-chain (AL) amyloidosis is a systemic syndrome characterized by progressive organ dysfunction leading to organ failure and death. The heart is the most commonly involved organ and the leading determinant of short- and long-term survival. Pathogenic free light chains, fragments of intact immunoglobulins, are the amyloidogenic proteins and are secreted by clonal bone marrow plasma cells. The goal of therapy is to cut off the supply of these light chains to allow organ recovery. Therapies for AL amyloidosis are based on therapies used to treat multiple myeloma, which is a more common plasma cell disorder. However, because patients with AL amyloidosis have organ dysfunction, including multiorgan involvement, they generally have poor treatment tolerance and increased treatment toxicity. Unfortunately, the consequences of toxicity and difficulty in tolerating treatment may result in a fatal outcome. Therefore, treatment should balance the goal of achieving a rapid and meaningful reduction in the circulating light chains while maximizing patient safety. This approach is best achieved by a multidisciplinary approach involving related medical disciplines. This review describes the challenges of managing patients with AL amyloidosis and provides a guide for physicians with a specific focus on cardiac management. We address the role of autologous stem cell transplantation vs standard-intensity therapies in a risk-adapted approach and discuss the management of commonly encountered toxicities. Guidance on response assessment, including organ response, is provided. With expansion in treatment options, we anticipate continuous improvement in outcome for this disease. Nonetheless, early diagnosis remains the best approach to improve disease burden and outcome.