Cytogenetic intraclonal heterogeneity of plasma cell dyscrasia in AL amyloidosis as compared with multiple myeloma

Immunoglobulin light chain amyloidosis: 2024 update on diagnosis, prognosis, and treatment

DISEASE OVERVIEW

Immunoglobulin light chain amyloidosis is a clonal, nonproliferative plasma cell disorder in which fragments of immunoglobulin light or heavy chain are deposited in tissues. Clinical features depend on organs involved but can include heart failure with preserved ejection fraction, nephrotic syndrome, hepatic dysfunction, peripheral/autonomic neuropathy, and "atypical smoldering multiple myeloma or MGUS."

DIAGNOSIS

Tissue biopsy stained with Congo red demonstrating amyloid deposits with apple-green birefringence is required for the diagnosis of AL amyloidosis. Organ biopsy is not required in 85% of patients. Verification that amyloid is composed of immunoglobulin light chains is mandatory. The gold standard is laser capture mass spectroscopy.

PROGNOSIS

N-terminal pro-brain natriuretic peptide (NT-proBNP or BNP), serum troponin T(or I), and difference between involved and uninvolved immunoglobulin free light chain values are used to classify patients into four stages; 5-year survivals are 82%, 62%, 34%, and 20%, respectively.

THERAPY

All patients with a systemic amyloid syndrome require therapy to prevent deposition of amyloid in other organs and prevent progressive organ failure. Current first-line therapy with the best outcome is daratumumab, bortezomib, cyclophosphamide, and dexamethasone. The goal of therapy is a ≥VGPR. In patients failing to achieve this depth of response options for consolidation include pomalidomide, stem cell transplantation, venetoclax, and bendamustine.

FUTURE CHALLENGES

Delayed diagnosis remains a major obstacle to initiating effective therapy prior to the development of end-stage organ failure. Trials of antibodies to deplete deposited fibrils are underway.

Amyloidogenic light chains impair plasma cell survival

Systemic light chain amyloidosis (AL) is a clonal plasma cell disorder characterized by the deposition of misfolded immunoglobulin light chains (LC) as insoluble fibrils in organs. The lack of suitable models has hindered the investigation of the disease mechanisms. Our aim was to establish AL LC-producing plasma cell lines and use them to investigate the biology of the amyloidogenic clone. We used lentiviral vectors to generate cell lines expressing LC from patients suffering from AL amyloidosis. The AL LC-producing cell lines showed a significant decrease in proliferation, cell cycle arrest, and an increase in apoptosis and autophagy as compared with the multiple myeloma LC-producing cells. According to the results of RNA sequencing the AL LC-producing lines showed higher mitochondrial oxidative stress, and decreased activity of the Myc and cholesterol pathways. The neoplastic behavior of plasma cells is altered by the constitutive expression of amyloidogenic LC causing intracellular toxicity. This observation may explain the disparity in the malignant behavior of the amyloid clone compared to the myeloma clone. These findings should enable future in vitro studies and help delineate the unique cellular pathways of AL, thus expediting the development of specific treatments for patients with this disorder.

RNA-sequencing based first choice of treatment and determination of risk in multiple myeloma

Background

Immunotherapeutic targets in multiple myeloma (MM) have variable expression height and are partly expressed in subfractions of patients only. With increasing numbers of available compounds, strategies for appropriate choice of targets (combinations) are warranted. Simultaneously, risk assessment is advisable as patient's life expectancy varies between months and decades.

Methods

We first assess feasibility of RNA-sequencing in a multicenter trial (GMMG-MM5, n=604 patients). Next, we use a clinical routine cohort of untreated symptomatic myeloma patients undergoing autologous stem cell transplantation (n=535, median follow-up (FU) 64 months) to perform RNA-sequencing, gene expression profiling (GEP), and iFISH by ten-probe panel on CD138-purified malignant plasma cells. We subsequently compare target expression to plasma cell precursors, MGUS (n=59), asymptomatic (n=142) and relapsed (n=69) myeloma patients, myeloma cell lines (n=26), and between longitudinal samples (MM vs. relapsed MM). Data are validated using the independent MMRF CoMMpass-cohort (n=767, FU 31 months).

Results

RNA-sequencing is feasible in 90.8% of patients (GMMG-MM5). Actionable immune-oncological targets (n=19) can be divided in those expressed in all normal and >99% of MM-patients (CD38, SLAMF7, BCMA, GPRC5D, FCRH5, TACI, CD74, CD44, CD37, CD79B), those with expression loss in subfractions of MM-patients (BAFF-R [81.3%], CD19 [57.9%], CD20 [82.8%], CD22 [28.4%]), aberrantly expressed in MM (NY-ESO1/2 [12%], MUC1 [12.7%], CD30 [4.9%], mutated BRAF V600E/K [2.1%]), and resistance-conveying target-mutations e.g., against part but not all BCMA-directed treatments. Risk is assessable regarding proliferation, translated GEP- (UAMS70-, SKY92-, RS-score) and de novo (LfM-HRS) defined risk scores. LfM-HRS delineates three groups of 40%, 38%, and 22% of patients with 5-year and 12-year survival rates of 84% (49%), 67% (18%), and 32% (0%). R-ISS and RNA-sequencing identify partially overlapping patient populations, with R-ISS missing, e.g., 30% (22/72) of highly proliferative myeloma.

Conclusion

RNA-sequencing based assessment of risk and targets for first choice treatment is possible in clinical routine.

Cytogenetics in the management of multiple Myeloma: The guidelines from the Groupe Francophone de Cytogénétique Hématologique (GFCH)

Multiple myeloma (MM) is characterized by the accumulation of malignant plasma cells (PCs) in the bone marrow. Despite considerable advances in the treatment, MM is considered an incurable chronic disease with a very heterogeneous prognosis, mostly depending on genomic alterations whose complexity evolves over time. The cytogenetic analysis of MM is performed on CD138+ sorted PCs, in order to detect the following high risk cytogenetic abnormalities: t(4;14), 17p/TP53 deletion, 1q21 gain/amplification, 1p32 deletion, as well as t(11;14) because of its therapeutic implication. This minimal panel can be enlarged to detect other recurrent abnormalities, according to the prognostic score chosen by the laboratory. Although the knowledge of the genetic landscape of MM is evolving rapidly with improved molecular technologies, risk scores remain to be refined as they require more time for consensual validation. The GFCH present here the overview of genomics alterations identified in MM and related PCs diseases associated with their prognostic factor, when available, and recommendations from an expert group for identification and characterization of those alterations. This work is the update of previous 2016 recommendations.

Comparison of IGLV2-14 light chain sequences of patients with AL amyloidosis or multiple myeloma

Light chain amyloidosis (AL) is one of the most common forms of systemic amyloidosis and is caused by the deposition of insoluble fibrils derived from misfolded and aggregated immunoglobulin light chains (LC). To uncover the causes leading to this aggregation, we compared AL LC sequences with those of patients with the related disease multiple myeloma (MM), which do not aggregate in insoluble fibrils in vivo. IGLV2-14 is one of the most common AL-associated IGLV subfamilies. Here, we analysed IGLV2-14 LC sequences of 13 AL and eight MM patients in detail. We found that AL-associated LCs presented a lower median mutation count (7.0 vs. 11.5 in MM; P = 0.045), as well as an overall composition of less charged amino acids than MM LCs. However, we did not find a mutation that was present in ≥ 50% of the AL and not in the MM sequences. Furthermore, we did not find a significant difference in the isoelectric point (pI) in general, suggesting similar stability of the LCs in AL and MM. However, the subgroup of patients without a detectable heavy chain stood out. Surprisingly, they are characterized by an increase in mutation count (median 7.0 vs. 5.5) and pI (median 7.82 vs. 6.44, P = 0.043). In conclusion, our data suggest that the amount of mutations and the introduction of charges play a crucial role in AL fibril formation, as well as the absence or presence of a potential heavy chain binding partner.

Clinical Characteristics and Outcomes of Cyclin D1-Positive AL Amyloidosis

OBJECTIVES

To demonstrate the clinical features and prognostic impact of cyclin D1 positivity in patients with amyloid light chain amyloidosis (AL).

METHODS

We consecutively included 71 patients diagnosed with AL with cyclin D1 positivity between February 2008 and January 2022. t(11;14) was examined through interphase fluorescence in situ hybridization using bone marrow cells.

RESULTS

The median age of the patients was 73 years, and 53.5% were male. The underlying diseases included symptomatic multiple myeloma, smoldering multiple myeloma, Waldenström macroglobulinemia, and monoclonal gammopathy of undetermined significance, representing 33.8%, 26.8%, 2.8%, and 36.6%, respectively. The prevalence of cyclin D1 and t(11;14) was 38.0% and 34.7%, respectively. Higher frequency of light chain paraprotein type was seen in cyclin D1-positive patients with AL than in cyclin D1-negative patients (70.4% vs 18.2%). The median overall survival (OS) of patients with AL with and without cyclin D1 expression was 18.9 months and 73.1 months, respectively (P = .019). Early death occurred in 44.4% of cyclin D1-positive patients and 31.8% of cyclin D1-negative patients. Moreover, 83.3% of cyclin D1-positive patients and 21.4% of cyclin D1-negative patients died of cardiac causes.

CONCLUSIONS

Cyclin D1 immunohistochemistry accurately identified patients with t(11;14). Cyclin D1-positive patients had significantly inferior OS compared with cyclin D1-negative patients.

Diagnosis and Treatment of AL Amyloidosis

Systemic light chain (AL) amyloidosis is caused by an usually small B cell clone that produces a toxic light chain forming amyloid deposits in tissue. The heart and kidney are the major organs affected, but all others, with the exception of the CNS, can be involved. The disease is rapidly progressive, and it is still diagnosed late. Screening programs in patients followed by hematologists for plasma cell dyscrasias should be considered. The diagnosis requires demonstration in a tissue biopsy of amyloid deposits formed by immunoglobulin light chains. The workup of patients with AL amyloidosis requires adequate technology and expertise, and patients should be referred to specialized centers whenever possible. Stagings are based on cardiac and renal biomarkers and guides the choice of treatment. The combination of daratumumab, cyclophosphamide, bortezomib and dexamethasone (dara-CyBorD) is the current standard of care. Autologous stem cell transplant is performed in eligible patients, especially those who do not attain a satisfactory response to dara-CyBorD. Passive immunotherapy targeting the amyloid deposits combined with chemo-/immune-therapy targeting the amyloid clone is currently being tested in controlled clinical trials. Response to therapy is assessed based on validated criteria. Profound hematologic response is the early goal of treatment and should be accompanied over time by deepening organ response. Many relapsed/refractory patients are also treated with daratumumab combination, but novel regimens will be needed to rescue daratumumab-exposed subjects. Immunomodulatory drugs are the current cornerstone of rescue therapy, while immunotherapy targeting B-cell maturation antigen and inhibitors of Bcl-2 are promising alternatives.

Immunoglobulin Light Chain Amyloidosis: Diagnosis and Risk Assessment

Immunoglobulin light chain (AL) amyloidosis is a clonal plasma cell disorder with multiple clinical presentations. The diagnosis of AL amyloidosis requires a high index of suspicion, making a delay in diagnosis common, which contributes to the high early mortality seen in this disease. Establishing the diagnosis of AL amyloidosis requires the demonstration of tissue deposition of amyloid fibrils. A bone marrow biopsy and fat pad aspirate performed concurrently have a high sensitivity for the diagnosis of AL amyloidosis and negate the need for organ biopsies in most patients. An accurate diagnosis requires amyloid typing via additional testing, including tissue mass spectrometry. Prognostication for AL amyloidosis is largely driven by the organs impacted. Cardiac involvement represents the single most important prognostic marker, and the existing staging systems are driven by cardiac biomarkers. Apart from organ involvement, plasma cell percentage on the bone marrow biopsy, specific fluorescence in situ hybridization findings, age at diagnosis, and performance status are important prognostic markers. This review elaborates on the diagnostic testing and prognostication for patients with newly diagnosed AL amyloidosis.

Current approaches to the diagnosis and management of amyloidosis

Amyloidosis is a collection of diseases caused by the misfolding of proteins that aggregate into insoluble amyloid fibrils and deposit in tissues. While these fibrils may aggregate to form insignificant localised deposits, they can also accumulate in multiple organs to the extent that amyloidosis can be an immediately life-threatening disease, requiring urgent treatment. Recent advances in diagnostic techniques and therapies are dramatically changing the disease landscape and patient prognosis. Delays in diagnosis and treatment remain the greatest challenge, necessitating physician awareness of the common clinical presentations that suggest amyloidosis. The most common types are transthyretin (ATTR) amyloidosis followed by immunoglobulin light-chain (AL) amyloidosis. While systemic AL amyloidosis was previously considered a death sentence with no effective therapies, significant improvement in patient survival has occurred over the past 2 decades, driven by greater understanding of the disease process, risk-adapted adoption of myeloma therapies such as proteosome inhibitors (bortezomib) and monoclonal antibodies (daratumumab) and improved supportive care. ATTR amyloidosis is an underdiagnosed cause of heart failure. Technetium scintigraphy has made noninvasive diagnosis much easier, and ATTR is now recognised as the most common type of amyloidosis because of the increased identification of age-related ATTR. There are emerging ATTR treatments that slow disease progression, decrease patient hospitalisations and improve patient quality of life and survival. This review aims to update physicians on recent developments in amyloidosis diagnosis and management and to provide a diagnostic and treatment framework to improve the management of patients with all forms of amyloidosis.

Immunoglobulin light chain amyloidosis: 2022 update on diagnosis, prognosis, and treatment

DISEASE OVERVIEW

Immunoglobulin light chain amyloidosis is a clonal, nonproliferative plasma cell disorder in which fragments of immunoglobulin light or heavy chain are deposited in tissues. Clinical features depend on organs involved but can include heart failure with preserved ejection fraction, nephrotic syndrome, hepatic dysfunction, peripheral/autonomic neuropathy, and "atypical smoldering multiple myeloma or monoclonal gammopathy of undetermined significance (MGUS)."

DIAGNOSIS

Tissue biopsy stained with Congo red demonstrating amyloid deposits with apple-green birefringence is required for the diagnosis of AL amyloidosis. Invasive organ biopsy is not required in 85% of patients. Verification that amyloid is composed of immunoglobulin light chains is mandatory. The gold standard is laser capture mass spectroscopy.

PROGNOSIS

N-terminal pro-brain natriuretic peptide (NT-proBNP or BNP), serum troponin T (or I), and difference between involved and uninvolved immunoglobulin free light chain values are used to classify patients into four groups of similar size; median survivals are 73, 35, 15, and 5 months.

THERAPY

All patients with a systemic amyloid syndrome require therapy to prevent deposition of amyloid in other organs and prevent progressive organ failure. Current first-line therapy with the best outcome is daratumumab, bortezomib, cyclophosphamide, and dexamethasone. The goal of therapy is a complete response (CR). In patients failing to achieve this depth of response options for consolidation include pomalidomide, stem cell transplantation, venetoclax, and bendamustine.

FUTURE CHALLENGES

Delayed diagnosis remains a major obstacle to initiating effective therapy prior to the development of end-stage organ failure. Trials of antibodies to catabolize deposited fibrils are underway.

The potential role of mass spectrometry for the identification and monitoring of patients with plasma cell disorders: Where are we now and which questions remain unanswered?

Mass spectrometry (MS) techniques provide a highly sensitive methodology for the assessment and monitoring of paraproteins compared to standard electrophoretic techniques. The International Myeloma Working Group (IMWG) recently approved the use of intact light chain matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in lieu of immunofixation in the clinical assessment of patients and the assessment of patients enrolled on clinical trials. The increased sensitivity of these assays may help to detect and monitor monoclonal proteins (MP) in many patients with previously non-measurable disease, will reduce complete response (CR) rates and increase detection of low-level MP. The ability to track the unique mass or amino acid sequence of the MP also eliminates interference from therapeutic monoclonal antibodies (tmAbs) in most patients with IgG kappa myeloma. The intact light chain assays also provide structural information about the monoclonal light chain, including the presence of N-linked glycosylation, which has been shown to be commoner on amyloidogenic light chains and may have prognostic significance in monoclonal gammopathy of undetermined significance (MGUS). In this review, we discuss these issues alongside differences in the analytical and practical aspects related to the different MS assays under development and the challenges for MS.

Analysis of the complete lambda light chain germline usage in patients with AL amyloidosis and dominant heart or kidney involvement

Light chain amyloidosis is one of the most common forms of systemic amyloidosis. The disease is caused by the misfolding and aggregation of immunoglobulin light chains to insoluble fibrils. These fibrils can deposit in different tissues and organs such as heart and kidney and cause organ impairments that define the clinical presentation. In this study, we present an overview of IGLV-IGLJ and IGLC germline utilization in 85 patients classified in three clinically important subgroups with dominant cardiac, renal as well as cardiac and renal involvement. We found that IGLV3 was the most frequently detected IGLV-family in patients with dominant cardiac involvement, whereas in renal patients IGLV1 were most frequently identified. For patients with dominant heart and kidney involvement IGLV6 was the most frequently detected IGLV-family. In more detailed analysis IGLV3-21 was observed as the most dominant IGLV-subfamily for patients with dominant heart involvement and IGLV1-44 as the most frequent IGLV-subfamily in the group of patients with dominant kidney involvement. For patients with dominant heart and kidney involvement IGLV6-57 was the most frequently detected IGLV-subfamily. Additionally, we were able to show an exclusive linkage between IGLJ1 and IGLC1 as well as between IGLJ2 and IGLC2 in the fully assembled IGL mRNA.

Genome Instability in Multiple Myeloma: Facts and Factors

Multiple myeloma (MM) is a malignant neoplasm of terminally differentiated immunoglobulin-producing B lymphocytes called plasma cells. MM is the second most common hematologic malignancy, and it poses a heavy economic and social burden because it remains incurable and confers a profound disability to patients. Despite current progress in MM treatment, the disease invariably recurs, even after the transplantation of autologous hematopoietic stem cells (ASCT). Biological processes leading to a pathological myeloma clone and the mechanisms of further evolution of the disease are far from complete understanding. Genetically, MM is a complex disease that demonstrates a high level of heterogeneity. Myeloma genomes carry numerous genetic changes, including structural genome variations and chromosomal gains and losses, and these changes occur in combinations with point mutations affecting various cellular pathways, including genome maintenance. MM genome instability in its extreme is manifested in mutation kataegis and complex genomic rearrangements: chromothripsis, templated insertions, and chromoplexy. Chemotherapeutic agents used to treat MM add another level of complexity because many of them exacerbate genome instability. Genome abnormalities are driver events and deciphering their mechanisms will help understand the causes of MM and play a pivotal role in developing new therapies.

How I Treat AL Amyloidosis

The treatment of patients with systemic light chain (AL) amyloidosis is a challenge to hematologists. Despite its generally small size, the underlying clone causes a rapidly progressing, often devastating multiorgan dysfunction through the toxic light chains that form amyloid deposits. Clinical manifestations are deceitful and too often recognized at an irreversible stage. However, hematologists are in the unique position to diagnose AL amyloidosis at a pre-symptomatic stage checking biomarkers of amyloid organ involvement in patients with monoclonal gammopathies at higher risk to develop the disease. Adequate technology and expertise are needed for a prompt and correct diagnosis, particularly for ruling out non-AL amyloidoses that are now also treatable. Therapy should be carefully tailored based on severity of organ involvement and clonal characteristics, and early and continual monitoring of response is critical. Three recent randomized clinical trials moved AL amyloidosis to evidence-based era. Above all, the daratumumab-bortezomib combination is a new standard-of-care for newly diagnosed patients inducing rapid and deep responses that translate into high rates of organ response. The availability of new effective drugs allows to better personalize the therapy, reduce toxicity, and improve outcomes. Patients should be treated within clinical trials whenever possible.

Lenalidomide and dexamethasone in relapsed/refractory immunoglobulin light chain (AL) amyloidosis: results from a large cohort of patients with long follow-up

Lenalidomide and dexamethasone (RD) is a standard treatment in relapsed/refractory immunoglobulin light chain (AL) amyloidosis (RRAL). We retrospectively investigated toxicity, efficacy and prognostic markers in 260 patients with RRAL. Patients received a median of two prior treatment lines (68% had been bortezomib-refractory; 33% had received high-dose melphalan). The median treatment duration was four cycles. The 3-month haematological response rate was 31% [very good haematological response (VGHR) in 18%]. The median follow-up was 56·5 months and the median overall survival (OS) and haematological event-free survival (haemEFS) were 32 and 9 months. The 2-year dialysis rate was 15%. VGHR resulted in better OS (62 vs. 26 months, P < 0·001). Cardiac progression predicted worse survival (22 vs. 40 months, P = 0·027), although N-terminal prohormone of brain natriuretic peptide (NT-proBNP) increase was frequently observed. Multivariable analysis identified these prognostic factors: NT-proBNP for OS [hazard ratio (HR) 1·71; P < 0·001]; gain 1q21 for haemEFS (HR 1·68, P = 0·014), with a trend for OS (HR 1·47, P = 0·084); difference between involved and uninvolved free light chains (dFLC) and light chain isotype for OS (HR 2·22, P < 0·001; HR 1·62, P = 0·016) and haemEFS (HR 1·88, P < 0·001; HR 1·59, P = 0·008). Estimated glomerular filtration rate (HR 0·71, P = 0·004) and 24-h proteinuria (HR 1·10, P = 0·004) were prognostic for renal survival. In conclusion, clonal and organ biomarkers at baseline identify patients with favourable outcome, while VGHR and cardiac progression define prognosis during RD treatment.

Genetic pathogenesis of immunoglobulin light chain amyloidosis: basic characteristics and clinical applications

Immunoglobulin light chain amyloidosis (AL) is an indolent plasma cell disorder characterized by free immunoglobulin light chain (FLC) misfolding and amyloid fibril deposition. The cytogenetic pattern of AL shows profound similarity with that of other plasma cell disorders but harbors distinct features. AL can be classified into two primary subtypes: non-hyperdiploidy and hyperdiploidy. Non-hyperdiploidy usually involves immunoglobulin heavy chain translocations, and t(11;14) is the hallmark of this disease. T(11;14) is associated with low plasma cell count but high FLC level and displays distinct response outcomes to different treatment modalities. Hyperdiploidy is associated with plasmacytosis and subclone formation, and it generally confers a neutral or inferior prognostic outcome. Other chromosome abnormalities and driver gene mutations are considered as secondary cytogenetic aberrations that occur during disease evolution. These genetic aberrations contribute to the proliferation of plasma cells, which secrete excess FLC for amyloid deposition. Other genetic factors, such as specific usage of immunoglobulin light chain germline genes and light chain somatic mutations, also play an essential role in amyloid fibril deposition in AL. This paper will propose a framework of AL classification based on genetic aberrations and discuss the amyloid formation of AL from a genetic aspect.

Daratumumab in the Treatment of Light-Chain (AL) Amyloidosis

Systemic light-chain (AL) amyloidosis is caused by a small B cell, most commonly a plasma cell (PC), clone that produces toxic light chains (LC) that cause organ dysfunction and deposits in tissues. Due to the production of amyloidogenic, misfolded LC, AL PCs display peculiar biologic features. The small, indolent plasma cell clone is an ideal target for anti-CD38 immunotherapy. A recent phase III randomized study showed that in newly diagnosed patients, the addition of daratumumab to the standard of care increased the rate and depth of the hematologic response and granted more frequent organ responses. In the relapsed/refractory setting, daratumumab alone or as part of combination regimens gave very promising results. It is likely that daratumumab-based regimens will become new standards of care in AL amyloidosis. Another anti-CD38 monoclonal antibody, isatuximab, is at an earlier stage of development as a treatment for AL amyloidosis. The ability to target CD38 on the amyloid PC offers new powerful tools to treat AL amyloidosis. Future studies should define the preferable agents to combine with daratumumab upfront and in the rescue setting and assess the role of maintenance. In this review, we summarize the rationale for using anti-CD38 antibodies in the treatment of AL amyloidosis.

Venetoclax induces deep hematologic remissions in t(11;14) relapsed/refractory AL amyloidosis

Venetoclax is efficacious in relapsed/refractory t(11;14) multiple myeloma, thus warranting investigation in light-chain amyloidosis (AL). This retrospective cohort includes 43 patients with previously treated AL, from 14 centers in the US and Europe. Thirty-one patients harbored t(11;14), 11 did not, and one t(11;14) status was unknown. Patients received a venetoclax-containing regimen for at least one 21- or 28-day cycle; the median prior treatments was three. The hematologic response rate for all patients was 68%; 63% achieved VGPR/CR. t(11;14) patients had higher hematologic response (81% vs. 40%) and higher VGPR/CR rate (78% vs. 30%, odds ratio: 0.12, 95% CI 0.02–0.62) than non-t(11;14) patients. For the unsegregated cohort, median progression-free survival (PFS) was 31.0 months and median OS was not reached (NR). For t(11;14), median PFS was NR and for non-t(11;14) median PFS was 6.7 months (HR: 0.14, 95% CI 0.04–0.53). Multivariate analysis incorporating age, sex, prior lines of therapy, and disease stage suggested a risk reduction for progression or death in t(11;14) patients. Median OS was NR for either subgroup. The organ response rate was 38%; most responders harbored t(11;14). Grade 3 or higher adverse events occurred in 19% with 7% due to infections. These promising results require confirmation in a randomized clinical trial.

AL amyloidosis: The effect of fluorescent in situ hybridization abnormalities on organ involvement and survival

Background

Systemic light chain (AL) amyloidosis is a clonal plasma‐cell neoplasm that carries a poor prognosis. Although AL amyloidosis and Multiple Myeloma (MM) can co‐exist and share various cytogenetic chromosomal abnormalities, little is known about Fluorescent in situ hybridization (FISH) and its prognostic relevance in AL amyloidosis.

Aim:

The study aims to evaluate the most prevalent FISH cytogenetic abnormalities in AL patients as independent prognostic factors, and assess the impact of cytogenetics on the survival of high‐risk cardiac AL patients.

Materials & Methods

This retrospective study reviewed 113 consecutive AL patients treated at The Ohio State University (OSU). Patients were divided into subgroups based on FISH data obtained within 90 days of diagnosis. Hyperdiploidy was defined as trisomies of at least 2 chromosomal loci. Primary endpoints were progression free survival (PFS) and overall survival (OS). Kaplan Meier curves were used to calculate PFS and OS. The log‐rank test and Cox proportional hazard models were used to test the equality of survival functions and further evaluate the differences between groups.

Results

FISH abnormalities were detected in 76% of patients. Patients with abnormal FISH trended toward lower overall survival (OS) (p=0.06) and progression free survival (PFS) (p=0.06). The two most prevalent aberrations were translocation t(11;14) (39%) and hyperdiploidy‐overall (38%). Hyperdiploidy‐overall was associated with worsening PFS (p=0.018) and OS (p=0.03), confirmed in multivariable analysis. Patients with del 13q most frequently had cardiac involvement (p=0.006) and was associated with increased bone marrow plasmacytosis (p=0.02). Cardiac AL patients with no FISH abnormalities had much improved OS (p=0.012) and PFS (p=0.018)

Conclusions

Our findings ultimately reveal the association of hyperdiploidy on survival in AL amyloidosis patients, including the high‐risk cardiac AL population.

Updates in the Diagnosis and Management of AL Amyloidosis

PURPOSE OF REVIEW

Light chain (AL) amyloidosis is an insidious progressive disease which results in significant morbidity and inevitable mortality if not diagnosed and treated promptly. This review will highlight recent developments and summarize critical clinical points and updated practice changes for the clinician in 2020.

RECENT FINDINGS

Comparative analyses of staging systems, updated prognostic tools, and treatment response criteria now allow for improved patient stratification and treatment decisions; the role of minimal residual disease in response assessment is still being assessed. Clinical and genetic predictors for long-term survivors have been highlighted. Standard-of-care front-line bortezomib and the integration of anti-CD38 monoclonal antibodies in the relapsed disease have transformed treatment approach in recent years. Various clinical trials in the pipeline include novel anti-plasma cell therapies and therapies directed against amyloid deposits which promise to further advance the treatment landscape. Diagnosis, response assessment, and treatment paradigms for AL amyloidosis have evolved significantly in the past 15 years, translating into superior outcomes and increased chances of long-term survival for AL amyloidosis.

A pharmacist's review of the treatment of systemic light chain amyloidosis

OBJECTIVE

Systemic light-chain (AL) amyloidosis is an uncommon hematologic plasma cell dyscrasia that is becoming increasingly recognized. Therapeutic agents used in AL amyloidosis overlap with those used in multiple myeloma; however, differences in disease features change treatment efficacy and tolerance. Pharmacists must be cognizant of these distinctions. Herein, this review article provides an up-to-date guide to treatment considerations for systemic AL amyloidosis in both the front-line and relapsed settings.Data sources: A comprehensive literature search was performed using the PubMed/Medline database for articles published through (June 2020) regarding treatments for AL amyloidosis. Search criteria included therapies that are FDA approved for multiple myeloma, as well as investigational agents. This review of chemotherapeutic agents reflects the current clinical practice guidelines endorsed by NCCN along with commentary based on the experience of pharmacists from a tertiary-referral center treating many patients with AL amyloidosis. Data consists of randomized controlled trials, observational cohorts, case reports, and ongoing clinical trials.Data summary: Frontline options discussed here include high-dose melphalan with autologous stem cell transplantation and bortezomib-based regimens. Regarding the relapsed setting, supporting data are compiled and summarized for: bortezomib, ixazomib, carfilzomib, lenalidomide, pomalidomide, daratumumab, elotuzumab, isatuximab, venetoclax, NEOD001, and melflufen.

CONCLUSIONS

The treatment platform for AL amyloidosis is expanding with novel agents traditionally used in multiple myeloma being adopted and modified for use in AL amyloidosis. The pharmacist's familiarity with the clinical evidence base for these agents and how they fit into standard protocols for AL amyloidosis is critical as dosing and monitoring recommendations are unique from multiple myeloma.

Localized immunoglobulin light chain amyloidosis: Novel insights including prognostic factors for local progression

In localized light chain amyloidosis (locAL), amyloidogenic light chains (aLC) are produced and deposited locally by a B-cell clone. We present 293 patients with immunohistochemically confirmed locAL. Lung (nodular pulmonary) with 63 patients was the most involved organ. The aLC was λ in 217 cases (κ:λ ratio 1:3). A local B-cell clone was identified in 30% of cases. Sixty-one (21%) had a concomitant autoimmune disorder (cAD). A monoclonal component (MC) were present in 101 (34%) patients and were more frequent in subjects with cAD (51% vs 34%; P = .03). Cigarette smoking was more prevalent in lung locAL (54% vs 37%; P = .018). After a median follow-up of 44 months, 16 patients died and 5- and 10-years locAL progression-free survival (PFS) were 62% and 44%. Interestingly, locAL-PFS was shorter among patients with an identified clonal infiltrate at amyloid deposition site (40 vs 109 months; P = .02) and multinuclear giant cells and/or an inflammatory infiltrate resulted in longer locAL-PFS in lung involvement (65 vs 42 months; P = .01). However, no differences in locAL PFS were observed in patients with cAD, a MC and involved organ site. Treatment was administered in 163 (54%) patients and was surgical in 135 (46%). Median locAL-PFS after first treatment was 56 months. Responders had longer locAL-PFS (78 vs 17 months; P < .001). Three patients with lung locAL and a MC were diagnosed as systemic AL amyloidosis at follow-up. In summary, locAL pathogenesis seems to be heterogeneous and the clonal infiltrate leads local progression.

Systemic Amyloidosis Due to Clonal Plasma Cell Diseases

Immunoglobulin light chain amyloidosis is the most common systemic amyloidosis. The pathogenetic mechanism is deposition of fibrils of misfolded immunoglobulin free light chains, more often lambda, typically produced by clonal plasma cells. Distinct Ig light chain variable region genotypes underlie most light chain amyloidosis and dictate tissue tropism. Light chain amyloidosis fibrils cause distortion of the histologic architecture and direct cytotoxicity, leading to rapidly progressive organ dysfunction and eventually patient demise. A high index of clinical suspicion with rapid tissue diagnosis and commencement of combinatorial, highly effective cytoreductive therapy is crucial to avoid irreversible organ damage and early mortality.

Hunting down the dominating subclone of cancer stem cells as a potential new therapeutic target in multiple myeloma: An artificial intelligence perspective

The development of single-cell subclones, which can rapidly switch from dormant to dominant subclones, occur in the natural pathophysiology of multiple myeloma (MM) but is often "pressed" by the standard treatment of MM. These emerging subclones present a challenge, providing reservoirs for chemoresistant mutations. Technological advancement is required to track MM subclonal changes, as understanding MM's mechanism of evolution at the cellular level can prompt the development of new targeted ways of treating this disease. Current methods to study the evolution of subclones in MM rely on technologies capable of phenotypically and genotypically characterizing plasma cells, which include immunohistochemistry, flow cytometry, or cytogenetics. Still, all of these technologies may be limited by the sensitivity for picking up rare events. In contrast, more incisive methods such as RNA sequencing, comparative genomic hybridization, or whole-genome sequencing are not yet commonly used in clinical practice. Here we introduce the epidemiological diagnosis and prognosis of MM and review current methods for evaluating MM subclone evolution, such as minimal residual disease/multiparametric flow cytometry/next-generation sequencing, and their respective advantages and disadvantages. In addition, we propose our new single-cell method of evaluation to understand MM's mechanism of evolution at the molecular and cellular level and to prompt the development of new targeted ways of treating this disease, which has a broad prospect.

Immunoglobulin light chain amyloidosis: 2020 update on diagnosis, prognosis, and treatment

DISEASE OVERVIEW

Immunoglobulin light chain amyloidosis is a clonal, nonproliferative plasma cell disorder in which fragments of immunoglobulin light or heavy chain are deposited in tissues. Clinical features depend on organs involved but can include heart failure with preserved ejection fraction, nephrotic syndrome, hepatic dysfunction, peripheral/autonomic neuropathy, and "atypical smoldering multiple myeloma or monoclonal gammopathy undetermined significance (MGUS)."

DIAGNOSIS

Tissue biopsy stained with Congo red demonstrating amyloid deposits with apple-green birefringence is required for diagnosis. Invasive organ biopsy is not required in 85% of patients. Verification that amyloid is composed of immunoglobulin light chains is mandatory. The gold standard is laser capture mass spectroscopy.

PROGNOSIS

N-terminal pro-brain natriuretic peptide (NT-proBNP), serum troponin T, and difference between involved and uninvolved immunoglobulin free light chain (FLC) values are used to classify patients into four groups of similar size; median survivals are 94.1, 40.3, 14.0, and 5.8 months.

THERAPY

All patients with a systemic amyloid syndrome require therapy to prevent deposition of amyloid in other organs and prevent progressive organ failure. Stem cell transplant (SCT) is preferred, but only 20% of patients are eligible. Requirements for safe SCT include systolic blood pressure >90 mmHg, troponin T < 0.06 ng/mL and serum creatinine ≤1.7 mg/dL. Nontransplant candidates can be offered cyclophosphamide-bortezomib-dexamethasone or daratumumab-containing regimens as it appears to be highly active in AL amyloidosis.

FUTURE CHALLENGES

Delayed diagnosis remains a major obstacle to initiating effective therapy prior to the development of end-stage organ failure.

Daratumumab for systemic AL amyloidosis: prognostic factors and adverse outcome with nephrotic-range albuminuria

Daratumumab has shown promising first results in systemic amyloid light-chain (AL) amyloidosis. We analyzed a consecutive series of 168 patients with advanced AL receiving either daratumumab/dexamethasone (DD, n = 106) or daratumumab/bortezomib/dexamethasone (DVD, n = 62). DD achieved a remission rate (RR) of 64% and a very good hematologic remission (VGHR) rate of 48% after 3 months. Median hematologic event-free survival (hemEFS) was 11.8 months and median overall survival (OS) was 25.6 months. DVD achieved a 66% RR and a 55% VGHR rate. Median hemEFS was 19.1 months and median OS had not been reached. Cardiac organ responses were noted in 22% with DD and 26% with DVD after 6 months. Infectious complications were common (Common Terminology Criteria [CTC] grade 3/4: DD 16%, DVD 18%) and likely related to a high rate of lymphocytopenia (CTC grade 3/4: DD 20%, DVD 17%). On univariable analysis, hyperdiploidy and gain 1q21 conferred an adverse factor for OS and hemEFS with DD, whereas translocation t(11;14) was associated with a better hemEFS. N-terminal prohormone of brain natriuretic peptide &gt;8500 ng/L could not be overcome for survival with each regimen. Multivariable Cox regression analysis revealed plasma cell dyscrasia (difference between serum free light chains [dFLC]) &gt;180 mg/L as an overall strong negative prognostic factor. Additionally, nephrotic-range albuminuria with an albumin-to-creatinine-ratio (ACR) &gt;220 mg/mmol was a significantly adverse factor for hemEFS (hazard ratio, 2.1 and 3.1) with DD and DVD. Daratumumab salvage therapy produced good results and remission rates challenging any therapy in advanced AL. Outcome is adversely influenced by the activity of the underlying plasma cell dyscrasia (dFLC) and nephrotic-range albuminuria (ACR).

Nonlymphoplasmacytic lymphomas associated with light-chain amyloidosis

The authors report on the subset of AL amyloidosis patients with nonlymphoplasmacytic lymphoma, emphasizing a predominance of marginal zone lymphoma, frequent delay in diagnosis, and a generally poor prognosis.