Adverse Prognostic Factors for Morbidity and Mortality During Peripheral Blood Stem Cell Mobilization in Patients with Light Chain Amyloidosis

Role of autologous haematopoietic cell transplantation in the treatment of systemic light chain amyloidosis in the era of anti-CD38 monoclonal antibodies

The primary goal of the initial treatment in systemic light chain amyloidosis is to obtain a rapid and profound haematological response as safely as possible, coupled with supportive care by a multidisciplinary team. The treatment landscape has evolved with the introduction of highly effective therapies targeting the plasma cell clones, which can attain high rates of haematological complete response with minimal treatment-related morbidity and mortality. Consequently, the role of high-dose melphalan followed by autologous haematopoietic cell transplantation (HDM-AHCT) is being analysed, particularly considering the absence of randomised controlled trial data supporting its superiority over standard-dose therapies in systemic light chain amyloidosis treatment. In this Viewpoint, we will explore the role of HDM-AHCT in the management of patients with systemic light chain amyloidosis who are eligible for transplantation, and the unresolved questions surrounding HDM-AHCT use as both front-line and salvage therapy.

Cardiovascular toxicity from therapies for light chain amyloidosis

Amyloid light-chain (AL) amyloidosis is a hematological disorder characterized by abnormal proliferation of a plasma cell clone producing monoclonal free light chains that misfold and aggregate into insoluble fibrils in various tissues. Cardiac involvement is a common feature leading to restrictive cardiomyopathy and poor prognosis. Current first-line treatments aim at achieving hematological response by targeting the plasma cell clones, and these have been adapted from multiple myeloma therapy. Patients with AL amyloidosis often exhibit multiorgan involvement, making them susceptible to cancer therapy-related cardiovascular toxicity. Managing AL amyloidosis is a complex issue that requires enhanced knowledge of the cardio-oncological implications of hematological treatments. Future research should focus on implementing and validating primary and secondary prevention strategies and understanding the biochemical basis of oncological therapy-related damage to mitigate cardiovascular toxicity.

Pre-mobilization platelet count predicts stem cell yield during mobilization in patients with multiple myeloma

Background

Autologous hematopoietic stem cell (HSC) transplantation remains the recommended treatment for eligible patients with multiple myeloma (MM). Increasing the number of transplanted CD34+ cells shorten the time to hematopoietic reconstitution and increases the overall survival of patients. With the harvest of a sufficient CD34+ cell number being crucial, this study aimed to predict the factors that affect stem cell collection.

Methods

We conducted a retrospective study of 110 patients who were newly diagnosed with MM and underwent autologous HSC collection at Beijing Jishuitan Hospital between March 2016 and July 2022. Multiple factors were analyzed using the Mann-Whitney U tests for between-group comparisons. Differences were considered statistically significant at P ​< ​0.05.

Results

We found that patient age affected stem cell collection significantly; for patients younger than 55 years, the number of CD34+ cells harvested may be ​≥ ​2 ​× ​106/L, is unlikely to reach 5 ​× ​106/L. Platelet count at initial mobilization was a predictor of the number of CD34+ cells collected. Collection may fail when the platelet count at initial mobilization is below 177 ​× ​109/L and may be excellent when it is higher than 199 ​× ​109/L.

Conclusions

This finding could guide us to predict the approximate number of CD34+ cells collected in advance during autologous transplant mobilization for MM and to decide in advance whether to apply plerixafor to improve the number of HSCs collected.

Recent guidelines for high dose chemotherapy and autologous stem cell transplant for systemic AL amyloidosis: a practitioner's perspective

INTRODUCTION

High dose melphalan followed by autologous stem cell transplant (ASCT) has been transformative in treating AL amyloidosis since the early nineties. Recently, the European Haematology Association (EHA) and International Society of Amyloidosis (ISA) have developed a combined guideline for the management of patients undergoing an ASCT for AL amyloidosis.

AREAS COVERED

In this practitioner's perspective, we review the guideline, focussing on 6 major areas and offer practical advice for its application. We provide a perspective on the optimal use of ASCT and its potential application in the future.

EXPERT OPINION

The EHA-ISA guideline comprehensively outlines the practicalities of performing an ASCT in AL amyloidosis. The critical aspect is careful patient selection. Vigilant fluid balance assessments are crucial as associated complications are common and dangerous.The role of ASCT is changing with improving haematological responses associated with novel agents. Evidence is limited for the use of ASCT in patients who achieve a complete haematological response (CR). Therefore, ASCT should be considered for those who only achieve a very good partial response (VGPR)/partial response (PR) and fulfil the strict selection criteria. Future research identifying the cohort who would benefit most from ASCT in the era of novel therapies is warranted.

Guidelines for high dose chemotherapy and stem cell transplantation for systemic AL amyloidosis: EHA-ISA working group guidelines

AL amyloidosis is a systemic amyloidosis and is associated with an underlying plasma cell dyscrasia. High dose intravenous melphalan and autologous stem cell transplantation was developed for the treatment of AL amyloidosis in the early 1990s and was prompted by its success in multiple myeloma. This application has evolved significantly over the past three decades. These guidelines provide a comprehensive assessment of eligibility criteria, stem cell collection and mobilisation strategies and regimens, risk-adapted melphalan dosing, role for induction and consolidation therapies, specific supportive care management, long-term outcome with respect to survival, haematologic response and relapse and organ responses following stem cell transplantation. These guidelines are developed by the experts in the field on behalf of the stem cell transplant working group of the International Society of Amyloidosis (ISA) and European Haematology Association (EHA).

AL Amyloidosis: Current Chemotherapy and Immune Therapy Treatment Strategies: JACC: CardioOncology State-of-the-Art Review

Immunoglobulin light chain (AL) amyloidosis is an incurable plasma cell disorder characterized by deposition of fibrils of misfolded immunoglobulin free light chains (FLC) in target organs, leading to failure. Cardiac involvement is common in AL amyloidosis and represents the single most adverse prognostic feature. A high index of clinical suspicion with rapid tissue diagnosis and commencement of combinatorial, highly effective cytoreductive therapy is crucial to arrest the process of amyloid deposition and preserve organ function. The clinical use of molecularly targeted drugs, such as proteasome inhibitors and immunomodulatory agents, monoclonal antibodies such as daratumumab, and risk-adjusted autologous stem cell transplant in eligible patients, has radically changed the natural history of AL amyloidosis. Here, we review the state-of-the-art treatment landscape in AL amyloidosis with an eye toward future therapeutic venues to impact the outcome of this devastating illness.

Comprehensive Review of AL amyloidosis: some practical recommendations

Amyloid light chain (AL) amyloidosis is among the more common and more severe of the amyloidoses usually involving the slow proliferation of a bone-marrow-residing plasma cell (PC) clone and the secretion of unstable immunoglobulin-free light chains (FLC) that infiltrate peripheral tissues and result in detrimental end-organ damage. Disease presentation is rather vague, and the hallmark of treatment is early diagnosis before irreversible end-organ damage. Once diagnosed, treatment decision is transplant-driven whereby ~20% of patients are eligible for autologous stem cell transplantation (ASCT) with or without bortezomib-based induction. In the setting of ASCT-ineligibility, bortezomib plays a central role in upfront treatment with the recent addition of daratumumab to the current emerging standard of care. In general, management of AL amyloidosis is aimed at achieving deep, durable responses with very close monitoring for early detection of relapse/refractory disease. This article provides a comprehensive review of the management of patients with AL amyloidosis including goals of therapy, current treatment guidelines in the setting of both ASCT-eligibility and ineligibility, treatment response monitoring recommendations, toxicity management, and treatment of relapse/refractory disease.

Stem Cell Mobilization and Autologous Transplant for Immunoglobulin Light-Chain Amyloidosis

Stem cell transplantation was one of the first proven effective regimens for the management of immunoglobulin light-chain amyloidosis. Criteria for patient selection and the mobilization regimen become important features in ensuring a safe outcome. The technique of stem cell transplantation has evolved considerably in parallel with the development of new chemotherapeutic agents for the management of amyloidosis. Optimal outcomes require both the use of effective novel agent induction and appropriate application of high-dose chemotherapy with subsequent stem cell reconstitution.

High-Dose Melphalan and Autologous Peripheral Blood Stem Cell Transplantation in AL Amyloidosis

AL amyloidosis is a systemic amyloidosis and is associated with an underlying plasma cell dyscrasia. High-dose intravenous melphalan and autologous stem cell transplantation was developed for the treatment of AL amyloidosis in the early 1990s and was prompted by its success in myeloma. This application has evolved significantly over the past three decades. This review provides a comprehensive assessment of eligibility criteria, stem cell collection, and mobilization strategies and regimens, risk-adapted melphalan dosing, role for induction and consolidation therapies as well as long-term outcome with respect to survival, hematologic response and relapse as well as organ responses following stem cell transplantation. Continued efforts to refine patient selection and management, and incorporate novel anti-plasma cell agents in combination or sequentially to further improve outcomes in AL amyloidosis are also discussed.

An updated single center experience with plerixafor and granulocyte colony-stimulating factor for stem cell mobilization in light chain amyloidosis

The use of granulocyte-colony stimulating factor (G-CSF) with or without chemotherapy to mobilize hematopoietic progenitor cells (HPCs) can result in significant morbidity in light chain (AL) amyloidosis patients. Plerixafor, a strong inducer and mobilizer of HPCs, can be used as an adjunct to G-CSF to improve mobilization efficiency. We describe the outcomes for combined G-CSF/plerixafor mobilized patients with AL amyloidosis. We reviewed data of 53 consecutive AL amyloidosis patients who underwent combined G-CSF/plerixafor HPC mobilization between May 2011 and October 2017 at our institution. We evaluated patients for HPC collection efficiency, perimobilization toxicity and postautologous hematopoietic cell transplantation (autoHCT) outcomes. Median CD34⁺ cell collection was 12.4 × 10⁶  cells/kg (range 2.5 × 10⁶ to 34.1 × 10⁶  cells/kg) and 45 (85%) patients had collections of ≥5.0 × 10⁶ CD34⁺ cells/kg. There were no mobilization failures or perimobilization mortality. During mobilization, 37 (70%) patients had weight gain (median 1.3 kg, range 0.1-4) but none >10% body weight, 5 (10%) patients had diarrhea, and one patient each had hypotension and cardiac arrhythmia. Among the 31 patients analyzed for CD34 collection efficiency (CE), the median CD34 CE was 47% (range 36-62). At 5 years follow-up 82% and 84% of patients were progression-free and alive, respectively. Our results suggest that G-CSF/plerixafor mobilization is safe, well tolerated, and effective in AL amyloidosis.

High-dose melphalan and stem cell transplantation in systemic AL amyloidosis in the era of novel anti-plasma cell therapy: a comprehensive review

The application of high-dose melphalan and autologous stem cell transplant (SCT) to systemic AL amyloidosis (AL) has evolved over the past two decades and remains an important component of therapy for patients with AL. The era of novel agents created the opportunity to provide well -tolerated induction and post-SCT consolidation to AL patients eligible for SCT and the current availability of new monoclonal antibody therapies will likely provide additional opportunities to enhance the outcomes with SCT. In this review, we touch on the history of SCT for AL and examine the data on eligibility, mobilization, induction, risk-adapted melphalan dosing, engraftment, consolidation and maintenance, and long-term outcomes with SCT. We note that induction therapy may deprive some patients of the opportunity to proceed to SCT but is likely needed if the marrow plasmacytosis is > 10%, that risk-adapted melphalan dosing continues to be relevant, and that post-SCT consolidation improves the complete response rate as well as long-term overall survival. The importance of baseline cytogenetics is also highlighted, particularly for patients whose clonal plasma cells are ≤ 10% but harbor the t(11;14), because they may have improved survival with SCT.