Successful reduced intensity allogeneic stem cell transplantation for systemic AL amyloidosis

Role of Autologous Stem Cell Transplantation in Systemic Light Chain Amyloidosis

Systemic light chain (AL) amyloidosis is a multisystem disorder characterized by extracellular deposition of misfolded insoluble amyloid fibrils resulting in progressive organ dysfunction. AL. amyloidosis most commonly affects the heart, kidneys, gastrointestinal tract and peripheral nerves. Early mortality is chiefly determined by the degree of cardiac involvement. The aim of therapy is to rapidly reduce amyloidogenic light chain production by targeting the underlying clonal plasma or lymphoma cell population. High dose therapy with melphalan followed by autologous peripheral blood stem cell transplant (ASCT) continues to remain a highly effective treatment and is considered a standard of care for transplant eligible patients, which offers long term disease control in patients with AL amyloidosis. In recent years, several new therapeutic options have emerged (including anti-CD38 monoclonal antibodies) which are very effective alone or in combination in eradicating clonal plasma cells. In this review, we discuss the role of ASCT in the current setting of a rapidly evolving treatment landscape for patients with AL amyloidosis and provide our practice recommendations.

Update on treatment of light chain amyloidosis

Light chain amyloidosis is the most common type of amyloidosis as a consequence of protein misfolding of aggregates composed of amyloid fibrils. The clinical features are dependent on the organs involved, typically cardiac, renal, hepatic, peripheral and autonomic neuropathy and soft tissue. A tissue biopsy or fat aspirate is needed to confirm the presence/type of amyloid and prognostic tools are important in a risk stratified approach to treatment. Autologous stem cell transplant eligibility should be assessed at baseline, weighing the reversible or non-reversible contraindications, toxicity of treatment and chemotherapy alternatives available. Chemotherapy options include melphalan, thalidomide, bortezomib, lenalidomide, bendamustine in combination with dexamethasone. Many studies have explored these treatment modalities, with ongoing debate about the optimal first line and sequential treatment thereafter. Attaining a very good partial response or better is the treatment goal coupled with early assessment central to optimizing treatment. One major challenge remains increasing the awareness of this disease, frequently diagnosed late as the presenting symptoms mimic many other medical conditions. This review focuses on the treatments for light chain amyloidosis, how these treatments have evolved over the years, improved patient risk stratification, toxicities encountered and future directions.

Light chain (AL) amyloidosis: update on diagnosis and management

Light chain (AL) amyloidosis is a plasma cell dyscrasia characterized by the pathologic production of fibrillar proteins comprised of monoclonal light chains which deposit in tissues and cause organ dysfunction. The diagnosis can be challenging, requiring a biopsy and often specialized testing to confirm the subtype of systemic disease. The goal of treatment is eradication of the monoclonal plasma cell population and suppression of the pathologic light chains which can result in organ improvement and extend patient survival. Standard treatment approaches include high dose melphalan (HDM) followed by autologous hematopoietic stem cell transplantation (SCT) or oral melphalan with dexamethasone (MDex). The use of novel agents (thalidomide, lenalidomide and bortezomib) alone and in combination with steroids and alkylating agents has shown efficacy and continues to be explored. A risk adapted approach to SCT followed by novel agents as consolidation reduces treatment related mortality with promising outcomes. Immunotherapeutic approaches targeting pathologic plasma cells and amyloid precursor proteins or fibrils are being developed. Referral of patients to specialized centers focusing on AL amyloidosis and conducting clinical trials is essential to improving patient outcomes.