Shameem Mahmood

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.

A matched comparison of cyclophosphamide, bortezomib and dexamethasone (CVD) versus risk-adapted cyclophosphamide, thalidomide and dexamethasone (CTD) in AL amyloidosis

Despite improvements in therapy amyloid light-chain (AL) amyloidosis, there are few studies comparing different regimens. Here we present a matched comparison with 69 patients in each cohort examining upfront therapy with cyclophosphamide, bortezomib and dexamethasone (CVD) vs cyclophosphamide, thalidomide and dexamethasone (CTD). On an intention-to-treat basis, the overall response rates were 71.0% vs 79.7% in the CVD and CTD arms, respectively, (P=0.32). A higher complete response (CR) rate was observed in the CVD arm (40.5%) vs CTD (24.6%), P=0.046. One-year overall survival (OS) was 65.2% and 66.7% for CVD and CTD, respectively (P=0.87). The median progression-free survival (PFS) was 28.0 and 14.0 m for CVD and CTD, respectively (P=0.039). In a landmark analysis assessing outcomes performed at 6 months, the CR rate with CVD was 59.6% vs 34.0% for CTD (P=0.03). The 1-year OS was 96% with CVD and 92% with CTD (P=0.40). The median PFS with CVD was not reached and was 19.2 m with CTD, P=0.028). In summary, both regimens are unable to overcome the high rate of early deaths in AL amyloidosis. However, CVD correlates with improved depth of response and superior PFS supporting its use in the frontline setting. Further optimisation and better supportive-care strategies are required to increase the proportion of patients fully benefiting from therapy.

A study of implanted cardiac rhythm recorders in advanced cardiac AL amyloidosis

AIMS AL amyloidosis may respond to chemotherapy but two-thirds of patients with severe cardiac involvement die within a year of diagnosis, purportedly from tachyarrhythmias or electromechanical dissociation. We sought to characterize the nature of cardiac arrhythmias in severe cardiac AL amyloidosis using implanted cardiac rhythm recorders. METHODS AND RESULTS Implantable loop recorders (ILRs) were inserted within 24 h of baseline evaluation at the UK National Amyloidosis Centre, into 20 consecutive patients with newly diagnosed severe cardiac AL amyloidosis and symptoms of syncope or pre-syncope. Weekly ILR recordings and additional recordings at the time of symptoms were obtained. Median (range) follow-up from baseline was 308 (10-399) days. Thirteen patients died, and median survival in the whole cohort was 61 days from device insertion. In each of eight evaluable cases, death was heralded by bradycardia, usually associated with complete atrioventricular block (CAVB), followed shortly thereafter by pulseless electrical activity. Four patients received pacemakers, a median (range) of 7 (3-38) h after development of symptomatic CAVB, but these did not prevent rapid cardiac decompensation and death in three cases. Despite 272 loop recordings, there was only one episode of non-sustained ventricular tachycardia, which was preceded by severe bradycardia. Patients who died had significantly worse global left ventricular strain on echocardiography (P = 0.029) and reduced 6 min walk distance (P = 0.048) at baseline compared with survivors. CONCLUSIONS The discovery that bradyarrhythmias heralded terminal cardiac decompensation in most patients with severe cardiac AL amyloidosis supports a study of prophylactic pacemaker insertion in this patient population.

Natural history and outcomes in localised immunoglobulin light-chain amyloidosis: a long-term observational study

BACKGROUND Localised immunoglobulin light-chain amyloidosis, involving one type of tissue, is rare. Little systematic data exists regarding clinical presentations, course or outcomes, or risk of progression to systemic amyloidosis. We aimed to report clinical features and outcomes of a large series of patients with localised light-chain amyloidosis. METHODS We examined data for all patients with localised amyloidosis who were diagnosed, assessed, and followed at the UK National Amyloidosis Centre (NAC) between Jan 2, 1980, and Dec 15, 2011, from the NAC database and written records. The inclusion criteria was the presence of biopsy sample proven localised amyloidosis classified as biopsy proven amyloid deposition confined to one site or tissue proven by histology of the tissue examined), without any evidence of vital organ involvement, which was defined as cardiac, renal, or liver involvement or peripheral or autonomic neuropathy and treatment naive. FINDINGS We identified 606 patients with biopsy proven localised amyloidosis (likely light-chain type in 98%) from 5050 newly diagnosed patients with all types of amyloidosis. Median age was 59·5 years (IQR 50·2-74·5). The most common sites included bladder (95; 16%), laryngeal or tonsillar (92; 15%), cutaneous (84; 14%), and pulmonary nodular (47; 8%). 121 (20%) had a monoclonal immunoglobulin or abnormal circulating free light chains. At median follow-up of 74·4 months (IQR 37·2-132·0), seven (1%) patients progressed to systemic immunoglobin light-chain amyloidosis. 270 (51%) patients had one repeated treatment intervention and 112 (21%) had more than one repeated treatment interventions (predominantly localised debulking). The estimated 5-year overall survival was 90·6% (95% CI 87·7-92·9) and 10-year overall survival was 80·3% (75·1-84·1). In patients aged 70 years or older, median overall survival was 12·1 years (95% CI 10·5-13·7). INTERPRETATION Localised immunoglobulin light-chain amyloidosis has an excellent prognosis with no apparent effect on life expectancy. Evolution into systemic immunoglobulin light chain amyloidosis is very rare. FUNDING None.

Natural history and outcome of light chain deposition disease

Light chain deposition disease (LCDD) is characterized by the deposition of monotypic immunoglobulin light chains in the kidney, resulting in renal dysfunction. Fifty-three patients with biopsy-proven LCDD were prospectively followed at the UK National Amyloidosis Center. Median age at diagnosis was 56 years, and patients were followed for a median of 6.2 years (range, 1.1-14.0 years). Median renal survival from diagnosis by Kaplan-Meier analysis was 5.4 years, and median estimated patient survival was 14.0 years; 64% of patients were alive at censor. Sixty-two percent of patients required dialysis, and median survival from commencement of dialysis was 5.2 years. There was a strong association between hematologic response to chemotherapy and renal outcome, with a mean improvement in glomerular filtration rate (GFR) of 6.1 mL/min/year among those achieving a complete or very good partial hematologic response (VGPR) with chemotherapy, most of whom remained dialysis independent, compared with a mean GFR loss of 6.5 mL/min/year among those achieving only a partial or no hematologic response (P < .009), most of whom developed end-stage renal disease (ESRD; P = .005). Seven patients received a renal transplant, and among those whose underlying clonal disorder was in sustained remission, there was no recurrence of LCDD up to 9.7 years later. This study highlights the need to diagnose and treat LCDD early and to target at least a hematologic VGPR with chemotherapy, even among patients with advanced renal dysfunction, to delay progression to ESRD and prevent recurrence of LCDD in the renal allografts of those who subsequently receive a kidney transplant.

European Collaborative Study Defining Clinical Profile Outcomes and Novel Prognostic Criteria in Monoclonal Immunoglobulin M–Related Light Chain Amyloidosis

PURPOSE Immunoglobulin M (IgM)-related light chain (AL) amyloidosis, which accounts for 6% to 10% of all AL amyloidosis cases, is a rare and poorly studied clinical entity. Its natural history and management is not clearly defined. Prognostic and response criteria for AL amyloidosis in general have not been validated in this population. PATIENTS AND METHODS We retrospectively gathered data for 250 patients diagnosed with IgM AL amyloidosis from three European amyloidosis centers. Clinical features, hematologic response, and overall survival (OS) were analyzed. The current staging and response criteria in non-IgM AL amyloidosis was applied to this series to assess its utility in this patient cohort. RESULTS Patients with IgM AL amyloidosis have a significant IgM paraprotein (median, 10 g/L), less frequent lambda light chain isotype, and evaluable difference between involved and uninvolved free light chains (dFLCs; > 50 mg/L) in only two thirds of patients. Bone marrow showed clear non-Hodgkin lymphoma as the underlying disorder in 54% of patients. Cardiac involvement (45%) is less common but there is more frequent lymph node (20%) and neuropathic (28%) involvement compared with non-IgM AL. Fifty-seven percent of patients achieved a hematologic response (14% very good partial response/complete response [VGPR/CR]), with median OS not reached for patients achieving VGPR/CR, 64 months for PR, and 28 months for nonresponders (P < .001). On multivariate analysis, cardiac involvement, advanced Mayo disease stage, neuropathic involvement, and liver involvement were independent factors that had an impact on survival. Combining abnormal N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin T with liver involvement and the presence of neuropathy gives a better risk model: median OS of patients with none, one, or two or more abnormal factors was 90, 33, and 16 months, respectively. CONCLUSION IgM AL amyloidosis is a distinct clinical entity. Low-risk disease can be defined by combining cardiac involvement with novel prognostic markers. Deeper hematologic responses translate into improved outcomes, yet deep responses remain dismally poor, which highlights the urgent need for novel therapies.

Lenalidomide and dexamethasone for systemic AL amyloidosis following prior treatment with thalidomide or bortezomib regimens.

The outcomes and responses to treatment remain poorly studied among patients with systemic AL amyloidosis who require further treatment following prior novel agent‐based therapy. We report here treatment with lenalidomide‐dexamethasone in 84 AL amyloidosis patients with relapsed/refractory clonal disease following prior treatment with thalidomide (76%) and/or bortezomib (68%). On an intention‐to‐treat (ITT) basis, the overall haematological response rate was 61%, including 20% complete responses. The median overall survival (OS) has not been reached; 2‐year OS and progression‐free survival (PFS) was 84% and 73%, respectively. Achieving a free light chain (FLC) response was an independent good prognostic factor for OS in multivariate analysis. There was no impact of prior thalidomide or bortezomib therapy on response rate, OS or PFS. 16% achieved an organ response at 6 months, with a marked improvement in organ responses in patients on long term therapy (median duration 11 months) and 55% achieving renal responses by 18 months. Lenalidomide/dexamethasone therapy achieves good haematological responses in patients with AL amyloidosis with relapsed/refractory clonal disease. The rate of renal responses among patients who received prolonged treatment was unexpectedly high, raising the possibility that immunomodulatory effects of lenalidomide therapy might enhance the otherwise slow natural regression of amyloid deposits.

Prognostic utility of the Perugini grading of 99mTc-DPD scintigraphy in transthyretin (ATTR) amyloidosis and its relationship with skeletal muscle and soft tissue amyloid

Aims High-grade (Perugini grade 2 or 3) cardiac uptake on bone scintigraphy with 99mTechnetium labelled 3,3-diphosphono-1,2-propanodicarboxylic acid (99mTc-DPD) has lately been confirmed to have high diagnostic sensitivity and specificity for cardiac transthyretin (ATTR) amyloidosis. We sought to determine whether patient stratification by Perugini grade on 99mTc-DPD scintigraphy has prognostic significance in ATTR amyloidosis. Methods and results Patient survival from time of 99mTc-DPD scintigraphy was determined in 602 patients with ATTR amyloidosis, including 377 with wild-type ATTR (ATTRwt) and 225 with mutant ATTR (ATTRm) amyloidosis. Patients were stratified according to Perugini grade (0-3) on 99mTc-DPD scan. The prognostic significance of additional patient and disease-related factors at baseline were determined. In the whole cohort, the finding of a Perugini grade 0 99mTc-DPD scan (n = 28) was invariably associated with absence of cardiac amyloid according to consensus criteria as well as significantly better patient survival compared to a Perugini grade 1 (n = 28), 2 (n = 436) or 3 (n = 110) 99mTc-DPD scan (P < 0.005). There were no differences in survival between patients with a grade 1, grade 2 or grade 3 99mTc-DPD scan in ATTRwt (n = 369), V122I-associated ATTRm (n = 92) or T60A-associated ATTRm (n = 59) amyloidosis. Cardiac amyloid burden, determined by equilibrium contrast cardiac magnetic resonance imaging, was similar between patients with Perugini grade 2 and Perugini grade 3 99mTc-DPD scans but skeletal muscle/soft tissue to femur ratio was substantially higher in the latter group (P < 0.001). Conclusion 99mTc-DPD scintigraphy is exquisitely sensitive for identification of cardiac ATTR amyloid, but stratification by Perugini grade of positivity at diagnosis has no prognostic significance.

Diagnostic sensitivity of abdominal fat aspiration in cardiac amyloidosis

Abstract Aims Congo red staining of an endomyocardial biopsy is the diagnostic gold-standard in suspected cardiac amyloidosis (CA), but the procedure is associated with the risk, albeit small, of serious complications, and delay in diagnosis due to the requirement for technical expertise. In contrast, abdominal fat pad fine needle aspiration (FPFNA) is a simple, safe and well-established procedure in systemic amyloidosis, but its diagnostic sensitivity in patients with suspected CA remains unclear. Methods and results We assessed the diagnostic sensitivity of FPFNA in 600 consecutive patients diagnosed with CA [216 AL amyloidosis, 113 hereditary transthyretin (ATTRm), and 271 wild-type transthyretin (ATTRwt) amyloidosis] at our Centre. Amyloid was detected on Congo red staining of FPFNAs in 181/216 (84%) patients with cardiac AL amyloidosis, including 100, 97, and 78% of those with a large, moderate, and small whole-body amyloid burden, respectively, as assessed by serum amyloid P (SAP) component scintigraphy (P < 0.001); the deposits were successfully typed as AL by immunohistochemistry in 102/216 (47%) cases. Amyloid was detected in FPFNAs of 51/113 (45%) patients with ATTRm CA, and only 42/271 (15%) cases with ATTRwt CA. Conclusions FPFNA has reasonable diagnostic sensitivity in cardiac AL amyloidosis, particularly in patients with a large whole-body amyloid burden. Although the diagnostic sensitivity of FPFNA is substantially lower in transthyretin CA, particularly ATTRwt, it may nevertheless sometimes obviate the need for endomyocardial biopsy.

Stringent patient selection improves outcomes in systemic light-chain amyloidosis after autologous stem cell transplantation in the upfront and relapsed setting

Autologous stem cell transplantation (ASCT) is an effective treatment for amyloid light-chain (AL) amyloidosis leading to both deep and durable clonal responses with excellent median overall survival of over five years with those attaining a complete hematologic response and surviving relapse free