Treatment of 100 patients with primary amyloidosis: a randomized trial of melphalan, prednisone, and colchicine versus colchicine only

Amyloidosis-recent developments

OBJECTIVES

To describe the clinical presentation, diagnosis, classification, grading, evaluation of prognosis, and treatment of amyloidosis against the background of its pathomechanisms.

METHODS

PubMed and MEDLINE databases (1990 to October 2007) and internet were searched for the key word amyloidosis and evaluated on the basis of the authors' own clinical experience and work on the topic.

RESULTS

A clinical suspicion of amyloidosis arises when a patient with a chronic inflammatory disease, plasma cell dyscrasia, or a family history of hereditary amyloidosis develops "an amyloid syndrome" or more rare but specific signs. Microscopy of Congo red stained tissue specimens under polarized light shows birefringent amyloid, which is typed by identification of the amyloid precursor by immunohistochemistry, amino acid sequencing, or proteomics. The diagnosis can be supported by genetic tests. Amyloidosis now covers biochemically and clinically 27 distinct types in man and 9 in animals. Grading to mild, moderate, and severe disease based on laboratory tests and radiology is introduced. Prognosis is affected by the rate of synthesis and the concentration of the circulating precursor. Accurate diagnosis of the underlying disease is mandatory as the treatment is based on disease control and inhibition of amyloid precursor production. Organ-specific treatment, such as transplantation, hemodialysis, treatment of heart failure, pacemakers, and substitution to prevent nutritional deficiencies, is often needed.

CONCLUSIONS

As our knowledge of the pathogenesis of amyloidosis and the structure-function relationship of amyloid proteins increases, new therapies will be developed to prevent protein misfolding and aggregation, inhibit fibrillogenesis, and enhance clearance of amyloid.

Troponin T level as an exclusion criterion for stem cell transplantation in light-chain amyloidosis

The efficacy of stem cell transplantation in amyloidosis largely is determined by treatment-related mortality rates (range, 11-25%). Appropriate patient selection is essential to avoid this high mortality rate. Among 271 patients undergoing stem cell transplantation, troponin T was a powerful predictor of treatment-related mortality. Patients with troponin T levels of 0.06 microg/L or higher had a day-100 all-cause mortality rate of 28%. Patients with troponin T levels less than 0.06 microg/L had a day-100 all-cause mortality rate of 7% (P < 0.001). Troponin T levels should be measured in all patients before transplantation. Those with troponin T levels exceeding 0.06 microg/L should be considered for less toxic therapies until the clinically optimal use of stem cell transplantation is better defined by randomized clinical trials.

Risk-adapted autologous stem cell transplantation with adjuvant dexamethasone +/- thalidomide for systemic light-chain amyloidosis: results of a phase II trial

High-dose melphalan (MEL) with autologous stem cell transplant (SCT) is an effective therapy for systemic AL amyloidosis (AL), but treatment-related mortality (TRM) has historically been high. We performed a phase II trial of risk-adapted SCT followed by adjuvant dexamethasone (dex) and thalidomide (thal) in an attempt to reduce TRM and improve response rates. Patients (n = 45) with newly diagnosed AL involving < or =2 organ systems were assigned to MEL 100, 140, or 200 mg/m(2) with SCT, based on age, renal function and cardiac involvement. Patients with persistent clonal plasma cell disease 3 months post-SCT received 9 months of adjuvant thal/dex (or dex if there was a history of deep vein thrombosis or neuropathy). Organ involvement was kidney (67%), heart (24%), liver/GI (22%) and peripheral nervous system (18%), with 31% having two organs involved. TRM was 4.4%. Thirty-one patients began adjuvant therapy, with 16 (52%) completing 9 months of treatment and 13 (42%) achieving an improvement in haematological response. By intention-to-treat, overall haematological response rate was 71% (36% complete response), with 44% having organ responses. With a median follow-up of 31 months, 2-year survival was 84% (95% confidence interval: 73%, 94%). Risk-adapted SCT with adjuvant thal/dex is feasible and results in low TRM and high haematological and organ response rates in AL patients.

Soft tissue, joint, and bone manifestations of AL amyloidosis: clinical presentation, molecular features, and survival

OBJECTIVE

To characterize symptoms and signs of AL amyloidosis that may bring patients to the attention of rheumatologists, evaluate Ig V(L) gene usage in this subgroup of patients, and assess the impact of soft tissue and bone involvement and V(L) gene usage on survival.

METHODS

Clinical features of soft tissue and bone involvement were assessed in 191 patients with AL amyloidosis. V(L) gene sequencing was carried out to determine light-chain family, rate of somatic mutation, and evidence of antigen selection. The association of soft tissue and bone involvement with V(L) gene usage was assessed by logistic regression analysis, and survival time was analyzed using log rank tests and Cox regression models.

RESULTS

Soft tissue and bone involvement occurred in 42.9% of the patients, and 9.4% had dominant soft tissue and bone involvement. The most common manifestations were submandibular gland enlargement, macroglossia, and carpal tunnel syndrome. Dominant soft tissue and bone involvement was significantly associated with V(L)kappaI gene usage. Mutation rate and evidence of antigen selection in the V(L) genes were not found to be confounding factors, providing evidence against a contribution of autoimmunity in this type of AL amyloidosis. Survival time was initially longer in patients with dominant soft tissue and bone involvement than in patients with other dominant organ involvement; however, this difference diminished over time.

CONCLUSION

Amyloid infiltration into soft tissue, joints, periarticular structures, and bones can bring patients with AL amyloidosis to the attention of rheumatologists. Recognition of the presenting symptoms is essential for accurate diagnosis and appropriate treatment, since the long-term outlook for untreated patients with dominant soft tissue and bone involvement is not better than that for patients with other dominant features of AL amyloidosis.

Intracardiac thrombosis and embolism in patients with cardiac amyloidosis

BACKGROUND

Patients with primary amyloidosis (AL type) have a poor prognosis, in part due to frequent cardiac involvement. Although intracardiac thrombus has been reported in anecdotal cases, neither its frequency nor its role in causing mortality is known. Furthermore, the clinical and echocardiographic variables that may be associated with thromboembolism in cardiac amyloidosis have not been defined.

METHODS AND RESULTS

A total of 116 autopsy or explanted cases of cardiac amyloidosis (55 AL and 61 other type) were identified in the Mayo Clinic. Forty-six fatal nonamyloid trauma cases served as controls. Each heart was examined for intracardiac thrombus. The cause of death was determined from autopsy and clinical notes. Intracardiac thrombosis was identified in 38 hearts (33%). Twenty-three had 1 thrombus, whereas 15 had 2 to 5 thrombi. Although subjects in the AL group were younger and had less atrial fibrillation than those with other types of amyloidosis, the AL group had significantly more intracardiac thrombus (51% versus 16%, P<0.001) and more fatal embolic events (26% versus 8%, P<0.03). Control hearts had no intracardiac thrombus. The presence of both atrial fibrillation and AL was associated with an extremely high risk for thromboembolism (odds ratio 55.0 [95% confidence interval 8.1 to 1131.4]). By multivariate analysis, AL type (odds ratio 8.4 [95% confidence interval 1.8 to 51.2]) and left ventricular diastolic dysfunction (odds ratio 12.2 [95% confidence interval 2.7 to 72.7]) were independently associated with thromboembolism.

CONCLUSIONS

A high frequency of intracardiac thrombosis was present in cardiac amyloidosis. Furthermore, thromboembolism caused significant fatality. Several risk factors for thromboembolism were identified. Early screening, especially in high-risk patients, and early anticoagulation might reduce morbidity and mortality.

High-dose melphalan versus melphalan plus dexamethasone for AL amyloidosis

BACKGROUND

High-dose chemotherapy followed by autologous hematopoietic stem-cell transplantation has been reported to provide higher response rates and better overall survival than standard chemotherapy in immunoglobulin-light-chain (AL) amyloidosis, but these two strategies have not been compared in a randomized study.

METHODS

We conducted a randomized trial comparing high-dose intravenous melphalan followed by autologous hematopoietic stem-cell rescue with standard-dose melphalan plus high-dose dexamethasone in patients with AL amyloidosis. Patients (age range, 18 to 70 years) with newly diagnosed AL amyloidosis were randomly assigned to receive intravenous high-dose melphalan plus autologous stem cells or oral melphalan plus oral high-dose dexamethasone.

RESULTS

Fifty patients were enrolled in each group. The results were analyzed on an intention-to-treat basis, with overall survival as the primary end point. After a median follow-up of 3 years, the estimated median overall survival was 22.2 months in the group assigned to receive high-dose melphalan and 56.9 months in the group assigned to receive melphalan plus high-dose dexamethasone (P=0.04). Among patients with high-risk disease, overall survival was similar in the two groups. Among patients with low-risk disease, there was a nonsignificant difference between the two groups in overall survival at 3 years (58% in the group assigned to receive high-dose melphalan vs. 80% in the group assigned to receive melphalan plus high-dose dexamethasone; P=0.13).

CONCLUSIONS

The outcome of treatment of AL amyloidosis with high-dose melphalan plus autologous stem-cell rescue was not superior to the outcome with standard-dose melphalan plus dexamethasone. (ClinicalTrials.gov number, NCT00344526 [ClinicalTrials.gov].).

[Carpal tunnel syndrome as a predictor of isolated systemic primary AL amyloidosis]

The diagnosis of common carpal tunnel syndrome, usually relies only on clinical grounds and electromyographic study. We present a 60-year-old woman who was diagnosed with systemic primary AL amyloidosis many years after the carpal tunnel syndrome had begun.

Long-term outcome of patients with AL amyloidosis treated with high-dose melphalan and stem-cell transplantation

Long-term survival and outcome were determined for 80 patients with immunoglobulin light chain (AL) amyloidosis treated with high-dose melphalan and stem cell transplantation (HDM/SCT) more than 10 years ago. Seventeen (21%) patients died within the first year of treatment, of treatment-related complications (14%) or progressive disease (8%). Of the 63 surviving evaluable patients at one year, 32 (51%) achieved a complete hematologic response (CR). For all 80 patients, the median survival was 57 months (4.75 yrs). The median survival exceeds 10 years for patients achieving a CR after HDM/SCT, compared with 50 months for those not achieving a CR (P < .001). In conclusion, HDM/SCT leads to durable remissions and prolonged survival, particularly for those patients who achieve a hematologic CR.

An unusual case of cardiac amyloidosis

Cardiac amyloidosis can result from any of the systemic amyloidoses. The disease is often characterized by a restrictive cardiomyopathy although the particular signs and symptoms depend in part on the underlying cause. In addition to managing the symptoms of heart failure, treatment options vary depending on the etiology of amyloid deposition. It is therefore critical to identify the cause of cardiac amyloidosis before initiating definitive therapy. We present a patient with presumed immunoglobulin (AL) amyloidosis who had a circulating lambda monoclonal protein, but a bone marrow biopsy with kappa predominant plasma cells. This unusual finding called into question the diagnosis of AL amyloidosis and highlights the importance and difficulty of determining the cause of cardiac amyloid deposition before initiating treatment. We review the different forms of cardiac amyloidosis and propose a diagnostic algorithm to help identify the etiology of cardiac amyloid deposition before beginning therapy.

Tandem cycles of high-dose melphalan and autologous stem cell transplantation increases the response rate in AL amyloidosis

Clinical outcomes of patients with AL amyloidosis treated with high-dose melphalan and stem cell transplantation (HDM/SCT) are tightly linked to the achievement of a hematologic complete response (HCR). We conducted a prospective trial to determine whether a second cycle of HDM/SCT could induce HCR in patients in whom the plasma cell dyscrasia persisted following initial treatment with HDM/SCT. Sixty-two patients were enrolled. Nine patients (15%) were removed from the protocol. Of the 53 patients continuing in this study, four died within 100 days of treatment (8%), and 27 (55%) achieved an HCR at 6 months after the first cycle of HDM/SCT. Of the 22 patients who did not achieve an HCR after initial treatment, 17 received a second HDM/SCT, 1 died within 100 days of treatment (6%), while 5 (31%) achieved an HCR. Thus, the HCR rate was 67% (32/48) for surviving patients on study, 60% (32/53) for all patients who received initial cycle of HDM/SCT, and 56% (35/62) by intention-to-treat. The median survival for all patients enrolled on the trial has not yet been reached. Thus, tandem cycles of HDM/SCT can increase the proportion of patients who achieve an HCR.

Paraproteinemic neuropathy

Paraproteinemia frequently is associated with peripheral neuropathy. The clinical manifestations can be protean owing to the potential for multiple organ involvement. A methodical diagnostic approach to patients who have a plasma cell dyscrasia and neuropathy is necessary to ensure the appropriate detection of more widespread systemic involvement.

Severity of Baseline Proteinuria Predicts Renal Response in Immunoglobulin Light Chain–Associated Amyloidosis after Autologous Stem Cell Transplantation

Ig light chain-associated amyloidosis is a fatal plasma cell proliferative disorder that is characterized by fibril deposition in various organs. High-dose melphalan followed by autologous stem cell transplantation has been shown to improve organ dysfunction and survival. This study was undertaken to investigate factors that influence renal response. Patients who had AL amyloidosis with > or =1 g/d proteinuria and a minimum follow-up of 12 mo were recruited. Renal response was defined by >50% reduction in proteinuria with <25% decline in renal function. Hematologic response was defined as a 50% reduction in serum monoclonal protein or free light chains. Baseline characteristics were examined for relationship to renal response. Thirteen of the 135 patients were excluded for various reasons. Median follow-up was 45.4 mo. Hematologic and renal response was noted in 73 and 43.4% of the patients, respectively. Median response time for the kidney was 10 mo (1 to 40 mo). In univariate analysis, low cardiac troponin T (cTnT), higher albumin, lower proteinuria, and hematologic response were associated with renal response. In multivariate analysis, cTnT and proteinuria were predictive of renal response. Renal response was associated with a longer survival than hematologic response alone. This study showed that severe proteinuria and high cTnT negatively affected renal response after autologous stem cell transplantation. Achievement of renal response was associated with improved survival. These results suggest that early intervention with aggressive therapy is not only justified but recommended to achieve optimal response.

Amyloidosis of the External Auditory Canal and Middle Ear: Unusual Ear Tumor

Amyloidosis of the ear is rare. We describe the case of a 41-year-old man who had localized amyloidosis that involved the external auditory canal and middle ear. To the best of our knowledge, only 4 other cases of amyloidosis involving the external auditory canal have been previously reported; in none of these cases was the middle ear involved. We also discuss the clinical importance of this condition and its treatment.

Autonomic Peripheral Neuropathy

Most generalized peripheral polyneuropathies are accompanied by clinical or subclinical autonomic dysfunction. There is a group of peripheral neuropathies in which the small or unmyelinated fibers are selectively targeted. In these neuropathies, autonomic dysfunction is the most prominent manifestation. The features associated with an autonomic neuropathy include impairment of cardiovascular, gastrointestinal, urogenital, thermoregulatory, sudomotor, and pupillomotor autonomic function.

Amyloidosis-associated kidney disease

The amyloidoses are a group of disorders in which soluble proteins aggregate and deposit extracellularly in tissues as insoluble fibrils, causing progressive organ dysfunction. The kidney is one of the most frequent sites of amyloid deposition in AL, AA, and several of the hereditary amyloidoses. Amyloid fibril formation begins with the misfolding of an amyloidogenic precursor protein. The misfolded variants self-aggregate in a highly ordered manner, generating protofilaments that interact to form fibrils. The fibrils have a characteristic appearance by electron microscopy and generate birefringence under polarized light when stained with Congo red dye. Advances in elucidating the mechanisms of amyloid fibril formation, tissue deposition, and tissue injury have led to new and more aggressive treatment approaches for these disorders. This article reviews the pathogenesis, diagnosis, clinical manifestations, and treatment of the amyloidoses, focusing heavily on the renal aspects of each of these areas.

Amyloidosis

Amyloidosis is a disease in which abnormal proteins form fibrillar tissue deposits that can compromise key viscera and lead to early death. In order to treat amyloidosis, the type of abnormal protein must be identified. The most common type is monoclonal immunoglobulin light chain or AL amyloidosis; the other important type is hereditary, caused by variant forms of transthyretin and other proteins, whereas amyloid associated with chronic inflammation ("secondary") is rare in the developed world. AL can be misdiagnosed if a monoclonal gammopathy and a hereditary variant are present in the same patient. The aim of therapy in systemic AL amyloidosis is to reduce the amyloid-forming monoclonal light chain, measured with the serum free light chain assay, by suppressing the underlying plasma cell dyscrasia, while using supportive measures to sustain organ function. Amyloid deposits can be resorbed and organ function restored if the amyloid-forming precursor light chain is eliminated. The most effective treatment for systemic AL amyloidosis is risk-adapted melphalan with peripheral blood stem cell transplant (SCT). The hematologic response rate is 75% at 12 months when adjuvant therapy with thalidomide and dexamethasone is used post-SCT. Patients can achieve long-term durable remissions with organ recovery. Drugs effective in multiple myeloma are usually helpful in AL amyloidosis if tolerated. The use of novel antibody-based approaches for imaging amyloid and possibly for accelerating removal of deposits is under active investigation.

Light-chain (AL) amyloidosis: diagnosis and treatment

Light-chain (AL) amyloidosis is the most common form of systemic amyloidosis and is associated with an underlying plasma cell dyscrasia. The disease often is difficult to recognize because of its broad range of manifestations and what often are vague symptoms. The clinical syndromes at presentation include nephrotic-range proteinuria with or without renal dysfunction, hepatomegaly, congestive heart failure, and autonomic or sensory neuropathy. Recent diagnostic and prognostic advances include the serum free light-chain assay, cardiac magnetic resonance imaging, and serologic cardiac biomarkers. Treatment strategies that have evolved during the past decade are prolonging survival and preserving organ function in patients with this disease. This review outlines approaches to diagnosis, assessment of disease severity, and treatment of AL amyloidosis.

An intriguing case of primary amyloidosis with cardiac involvement: Symptomatic and echocardiographic improvement with thalidomide treatment

Patients with primary amyloidosis (AL) have poor prognosis with a median survival of one to two years. In patients with symptomatic cardiac involvement, prognosis is even worse with the reported median survival of 6 months. One patient, diagnosed as AL amyloidosis with cardiac involvement, was treated with thalidomide and showed remarkable improvement in functional capacity, cardiac function, and various laboratory parameters without any significant adverse effect and, therefore, we report the case with the review of literatures.

The activity of lenalidomide with or without dexamethasone in patients with primary systemic amyloidosis

Primary systemic amyloidosis (AL) is an incurable plasma cell disorder. Lenalidomide, especially in conjunction with dexamethasone, is highly active in patients with multiple myeloma. We studied the toxicity and efficacy of lenalidomide in patients with AL. Patients with symptomatic AL, a measurable plasma cell disorder, and adequate hematologic and renal reserve were eligible. Patients received single-agent lenalidomide. If there was no evidence of progression after 3 months or of hematologic response after 3 cycles, dexamethasone was added. Twenty-three patients were enrolled. Thirteen were previously treated. Organ involvement was cardiac (64%), renal (73%), hepatic (23%), and nerve (14%). Within the first 3 cycles of therapy, 10 patients discontinued treatment: 4 early deaths, 3 adverse events, and 3 other causes. With a median follow-up of 17 months, 10 patients responded to treatment. In these patients, responses included 9 hematologic, 4 renal, 2 cardiac, and 2 hepatic. All but one of the responders had dexamethasone added to their treatment program. The most common grade 3 or 4 adverse events at least possibly attributable to lenalidomide were neutropenia (45%), thrombocytopenia (27%), rash (18%), and fatigue (18%). In AL patients, we saw limited activity of single-agent lenalidomide, but significant activity of the combination with dexamethasone, which warrants further investigation.

Lenalidomide and dexamethasone in the treatment of AL amyloidosis: results of a phase 2 trial

In immunoglobulin light chain (AL) amyloidosis, amyloid fibril deposits derived from immunoglobulin light chains produced by a clonal plasma cell dyscrasia accumulate in tissues and damage vital organs. Treatment regimens used in multiple myeloma can be effective in AL amyloidosis; however, patients with this disease often tolerate these regimens poorly because of multisystem organ dysfunction. Thalidomide and lenalidomide have both been shown to be effective in myeloma. In this report, we describe results of a phase 2 trial of the use of lenalidomide, as a single agent and in combination with dexamethasone, for the treatment of AL amyloidosis. Thirty-four patients with AL amyloidosis, most with prior therapies, were enrolled in the trial. The initial dose of lenalidomide used (25 mg/d) was poorly tolerated; however, a reduced dose of 15 mg/d was generally well tolerated. Of 24 evaluable patients, 7 (29%) achieved a hematologic complete response and 9 (38%) achieved a partial hematologic response, for an overall hematologic response rate of 67%. Hematologic responses were also associated with clinical responses. Fatigue and myelosuppression were the most common treatment-related adverse events (35%), while thromboembolic complications (9%) were the most serious. Findings from this trial indicate that lenalidomide can be effective in treating AL amyloidosis.

[Bullous amyloïdis revealing a light chains lambda myeloma]

INTRODUCTION

Although rare, skin lesions are regularly reported in patients with systemic amyloidosis. The existence of bullous skin lesions however is very rare; only thirty cases have been previously reported. We report a new case of bullous amyloidosis revealing a light chains lambda myeloma, and underline the usual characteristics of this type of systemic amyloidosis.

EXEGESIS

An 85-year-old man was hospitalised for a bullous eruption associated with a general asthenia. Bullous amyloidosis revealing a light chains lambda myeloma was diagnosed and confirmed by histopathological examination of a skin biopsy specimen. The patient died of a severe congestive heart failure, 15 days later, due to cardiac involvement of the amyloidosis.

CONCLUSION

Bullous amyloidosis lesions can be an early manifestation of occult dysglobulinemia. Early diagnosis would allow rapid treatment, before onset of systemic amyloidosis, which is often lethal.

Outcome of autologous stem cell transplantation for AL amyloidosis in the UK

High-dose chemotherapy with autologous stem cell transplantation (SCT) is widely used as a treatment for systemic AL amyloidosis, but its efficacy has not been proved and it has substantial toxicity in this setting. We report here the outcome of 92 patients evaluated at the UK National Amyloidosis Centre who underwent SCT for AL amyloidosis between 1994 and 2004 in various British centres. Median age was 53 years and median of two organs were affected by amyloidosis. All-cause day 100 mortality [treatment-related mortality (TRM)] was 23% for the entire cohort, although this was substantially greater for patients treated from 1994 to 1998 (15/47, 32%) than subsequently (6/45, 13%). Independent factors significantly associated with TRM on multivariate analysis were: number of affected organs, performance status, serum albumin and age. Response of the underlying clonal disease, defined by > or = 50% reduction in the aberrant serum-free light chain concentration, occurred in 83% of evaluable patients. Overall median survival was 5.3 years, and was 8.5 years among patients who survived beyond day 100. Despite recent refinements in patient selection, TRM remains substantial during SCT for systemic AL amyloidosis, and its place in the therapeutic armamentarium for this disease needs to be defined in randomised controlled clinical studies.

Review of randomised trials using the post-randomised consent (Zelen's) design

BACKGROUND

In 1979, Zelen described a trial method of randomising participants before acquiring consent in order to enhance recruitment to clinical trials. The method has been criticised ethically due to lack of consent and scientifically due to high crossover rates. This paper reviews recent published trials using this method and describes the reasons authors gave for using the method, examines the crossover rates, and looks at the quality of identified trials.

METHODS

Literature review searching for all citations to the relevant Zelen's papers of trials published since 1990 plus inclusion of trials from personal knowledge.

RESULTS

We identified 58 relevant trials. The most common justification for the use of Zelen method was to avoid the introduction of bias (e.g., to avoid the Hawthorne effect). Few trialists had explicitly used the design to enhance participant recruitment. Most trials (n=41) experienced some crossover from one group to the other (median crossover=8.9%, mean=13.8%, IQR 2.6% to 15%) although this was usually within acceptable limits.

CONCLUSION

The most important reason stated by authors for using Zelen's method was to limit bias. Zelen's method, if carefully used, can avoid 'resentful demoralisation' and the Hawthorne effect biasing a trial. Unlike a previous review, we found that crossover was not a problem for most trials.

[Cardiomyopathies II. Hypertrophic cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy]

This review focuses on hypertrophic (HCM), restrictive (RCM) and arrhythmogenic right ventricular cardiomyopathies (ARVC). The clinical phenotype of HCM depends not only on the gene mutations involved, but also on "modifier genes". It is characterized by an asymmetrical hypertrophy. Investigations of endomyocardial biopsies (EMBs) typically reveal a disarray of the hypertrophied cardiomyocytes. Percutaneous septum ablation has gained relevance as the treatment of choice in hypertrophic obstructive cardiomyopathy. Myocardial and endomyocardial RCM-forms can be differentiated. Enlargement of the atria in concert with normal dimensions of the ventricles and almost normal systolic contractility as well as the dip-plateau phenomenon are characteristic findings in RCM. EMB diagnostics are pivotal to identify the causes underlying secondary RCM types. Treatment is directed at heart failure and specifically at the underlying disease. With ARVC, apoptosis, viral infection/inflammation and genetic dystrophy result in fibrofatty degeneration primarily of the right, and with further progression also of the left ventricle. The primary treatment goal in ARVC is prevention of sudden cardiac death. As for other cardiomyopathies, there is increasing evidence for the superiority of ICD compared with pharmacological approaches.

Long-term outcome of high-dose melphalan and autologous stem cell transplantation for AL amyloidosis

Light chain (AL) amyloidosis is the result of a clonal plasma cell expansion, in which amyloidogenic monoclonal light chains deposit in various tissues resulting in organ dysfunction and organ failure. The median survival of patients with AL amyloidosis without therapy is 10-14 months. Several phase II studies report haematological and clinical remission in up to 50% of patients after high-dose melphalan and autologous stem cell transplantation. We analysed retrospectively the long-term outcome of 19 patients treated in this way between August/1996 and December/2001. We observed a relatively high treatment-related mortality of 26%, but 12 patients (63%) were high-risk candidates. Eight patients (42%) surviving longer than 100 days achieved haematological remission and long-term survival, whereas 6 (32%) obtained no clear benefit from high-dose therapy. However, 62% of patients survived beyond 2 years and the median survival from transplant was 48 months (range 0-104 months).

Amyloidosis: diagnosis and management

Amyloidosis is a rare plasma cell proliferative disorder. The annual incidence in Olmsted County, Minnesota, is 8 in 1,000,000 patients. This is a difficult disorder to diagnose, because the symptoms at presentation are vague and include dyspnea, paresthesias, edema, weight loss, and fatigue. The clinical syndromes at the time of presentation include nephrotic-range proteinuria with or without renal failure, cardiomyopathy, "atypical multiple myeloma," hepatomegaly, and autonomic or peripheral neuropathy. The serum immunoglobulin free light chain assay has been an important step forward in classifying systemic amyloidosis as an immunoglobulin light chain form and in monitoring therapy. Recently, the importance of serum cardiac biomarkers in assessing outcome has been recognized. New therapies developed over the past 5 years include high-dose chemotherapy with stem cell reconstitution, combinations of alkylating agents with dexamethasone, and, most recently, thalidomide.

Excessive fluid accumulation during stem cell mobilization: a novel prognostic factor of first-year survival after stem cell transplantation in AL amyloidosis patients

High-dose melphalan followed by stem cell transplantation (HDM-SCT) has become the treatment of choice for patients with immunoglobulin light chain amyloidosis (AL). Unfortunately, treatment mortality can be excessive in certain subpopulations. We have noted that patients who gained more than 2% body weight during mobilization had a poorer outcome following HDM-SCT. Excluding 2 patients for lack of weight record and denial of consent, 126 patients between July 1997 and June 2003 were retrospectively studied. Weight increased more than 2.0% during mobilization in 51.6% of the patients. Patients who accumulated more than 2.0% tended to have more proteinuria, more organs involved, lower serum albumin, more diuretic use, and dosage adjustment during mobilization. First-year mortality was significantly higher in those with more than 2% weight gain (33.9% versus 9.8%, P = .002). Multivariate analysis showed weight gain, glomerular filtration rate, and septal thickness to be independent predictors of first-year mortality. The increase in mortality was noted even after the excess weight was diuresed prior to conditioning. The impact on mortality dissipated after the first year. Weight gain during mobilization appears to be a new marker of adverse outcome following HDM-SCT. Better prognostication may improve the treatment mortality rate of these patients.

Clinical aspects of systemic amyloid diseases

Amyloidosis is a protein misfolding disorder in which soluble proteins aggregate as insoluble amyloid fibrils. Protein aggregates and amyloid fibrils cause functional and structural organ damage respectively. To date, at least 24 different proteins have been recognized as causative agents of amyloid diseases, localized or systemic. The two most common forms of systemic amyloidosis are light-chain (AL) amyloidosis and reactive AA amyloidosis due to chronic inflammatory diseases. beta(2)-microglobulin amyloidosis is a common complication associated with long-term hemodialysis. Hereditary systemic amyloidoses are a group of autosomal dominant disorders caused by mutations in the genes of several plasma proteins. Heterogeneity in clinical presentation, pattern of amyloid-related organ toxicity and rate of disease progression is observed among systemic amyloidoses. In particular, beta(2)-microglobulin presents unique clinical features compared to the other systemic forms. The phenotypic features of hereditary systemic amyloidoses may instead overlap those of the two more common forms of acquired amyloidoses mentioned above and therefore a correct diagnosis can not rely only on clinical grounds. Unequivocal identification of the deposited protein is essential in order to avoid misdiagnosis and inappropriate treatment. Amyloid deposits can be reabsorbed and organ dysfunction reversed if the concentration of the amyloidogenic protein is reduced or zeroed. At present, the most effective approach to treatment of the systemic amyloidoses involves shutting down, or substantially reducing the synthesis of the amyloid precursor, or, as in the case of beta(2)-microglobulin, promoting its clearance.

Renal response after high-dose melphalan and stem cell transplantation is a favorable marker in patients with primary systemic amyloidosis

BACKGROUND

Primary systemic (AL) amyloidosis is a rare plasma cell disorder characterized by soft-tissue deposition of monoclonal light chain fragments. High-dose melphalan followed by autologous stem cell transplantation currently has become the treatment of choice. Favorable outcome is ensured with achievement of hematologic response, but little is known about organ response. This study was undertaken to determine the prognostic importance of renal response after high-dose melphalan and stem cell transplantation.

METHODS

All patients with AL amyloidosis who underwent autologous stem cell transplantation between 1996 and December 2002 were selected for study. Renal response is defined as a 50% or greater reduction in proteinuria with less than 25% decline in renal function. Exclusion criteria included pretransplantation dialysis therapy or dialysis dependence posttransplantation, treatment mortality, lack of proteinuria assessment posttransplantation, and baseline proteinuria with protein less than 1 g/d.

RESULTS

Of 105 patients, 47 were excluded for stated reasons. Renal response was achieved in 60.3% of evaluated patients. Proteinuria was reduced by greater than 90% in 37.9% and returned to normal in 15.5%. Median response time was 12 months. Renal response was associated with a greater increase in serum albumin level (P = 0.001), maintenance of renal function (P < 0.001), and better survival (P = 0.0003). Renal responders had better survival regardless of hematologic response (P = 0.01 to 0.05).

CONCLUSION

Currently, high-dose melphalan followed by stem cell transplantation is the most effective treatment for AL amyloidosis for those who are eligible. Our data show that renal response after high-dose melphalan followed by stem cell transplantation is associated with improved survival. Renal response is an independent marker of treatment success and can be used in cases in which determination of hematologic response is difficult.

Amyloidosis

Amyloidosis is an uncommon plasma-cell dyscrasia with an incidence of eight patients per million per year. It is often difficult to recognize because of the myriad symptoms and vague nature of the clinical presentation. Symptoms include fatigue, dyspnea, edema, paresthesias, and weight loss. Clinical syndromes at presentation include nephrotic-range proteinuria with or without renal insufficiency, cardiomyopathy, hepatomegaly, symptomatic peripheral neuropathy, and autonomic failure. Recent advances have occurred in evaluation of patients by using the free light chain assay and new prognostic assessments with cardiac biomarkers. Newly developed therapeutic strategies, involving high-dose and intermediate-dose chemotherapy, have evolved in the last 3 years. This paper reviews a diagnostic pathway clinicians can use to diagnose the disorder, assess a patient's prognosis, and logically plan a therapeutic strategy.

Sequential heart and autologous stem cell transplantation for systemic AL amyloidosis

Extensive cardiac amyloid deposition in systemic AL amyloidosis is associated with a grave prognosis. Heart transplantation is rarely performed because of the systemic and progressive nature of the disease. Patients with severe cardiac amyloid infiltration are ineligible for the preferred treatment of melphalan chemotherapy with stem cell transplantation (SCT) rescue because of the high risk for treatment-related mortality. Heart transplantation followed by SCT was performed in 5 patients with AL amyloidosis and predominant cardiomyopathy. Patients were followed up for a median of 95 months (range, 37-118 months) from diagnosis. At censor, 3 of 5 patients were well without evidence of intracardiac or extracardiac amyloid accumulation, and median overall survival by Kaplan-Meier estimate was not reached. Two patients died of progressive amyloidosis 33 and 90 months after heart transplantation after relapse of their underlying plasma cell dyscrasia. Heart transplantation followed by SCT is feasible in selected patients with cardiac AL amyloidosis and may confer substantial survival benefit.

Autologous transplantation for primary systemic AL amyloidosis is feasible outside a major amyloidosis referral centre: the Calgary BMT Program experience

Recent reports from large amyloidosis referral centers suggest that primary systemic AL amyloidosis patients treated with high-dose melphalan (HDM) and autologous stem cell transplantation (ASCT) survive longer than historical controls treated with less intensive chemotherapy, despite high transplant-related mortality (TRM) rates of >10%. A retrospective review was conducted to determine if the outcome of ASCT for AL amyloidosis at our institution was similar to that reported at major amyloidosis referral centers. Over a 7 year period, we treated a total of 15 AL amyloidosis patients with ASCT, including four with poor prognosis cardiac or multisystem involvement. No TRM was observed. Overall, 10 patients (67%) achieved a complete hematological response and four patients (27%) achieved a complete organ response. The 4-year event-free and overall survival rates were 60% (95% CI 32-89%) and 75% (95% CI 50-100%), respectively. One patient, who presented with cardiac failure and multiorgan involvement with colonic bleeding currently remains in complete remission 62 months post-ASCT. In conclusion, ASCT for primary AL amyloidosis can safely be performed at experienced transplant centers that are not associated with major amyloidosis referral centers, and is feasible for patients who have multisystem involvement, particularly for motivated patients with good performance status.

Predictive factors for hematopoietic engraftment after autologous peripheral blood stem cell transplantation for AL amyloidosis

Treatment of patients with AL amyloidosis with high-dose melphalan and autologous peripheral blood stem cells (PBSC) produces hematologic remissions in approximately 40% of evaluable patients, accompanied by improvements in organ disease and quality of life. These patients, who frequently have amyloid deposits in bone marrow blood vessels and interstitium and impaired function of kidneys, liver, spleen, and heart, represent an unusual population for stem cell transplantation, with unique problems. To identify factors influencing engraftment rates after chemotherapy and autologous granulocyte colony-stimulating factor (G-CSF)-mobilized PBSC reinfusion, we studied a group of 225 patients. The median time to neutrophil engraftment was 10 days (range, 8-17 days). In a multivariate analysis, the factors positively affecting the rate of neutrophil engraftment were CD34+ stem cell dose, female gender, and minimal prior alkylator therapy. The median time to platelet engraftment was 13 days (range, 7-52 days). Factors positively affecting platelet engraftment, in addition to CD34+ cell dose, included preserved renal function and the absence of neutropenic fever. The conditioning dose of intravenous melphalan was not found to be an independent predictive factor for hematopoietic recovery. Thus, in this patient population, organ function and host and hematopoietic factors influence engraftment after PBSC rescue.

Living donor kidney and autologous stem cell transplantation for primary systemic amyloidosis (AL) with predominant renal involvement

Primary systemic amyloidosis (AL) is characterized by multiorgan deposition of monoclonal immunoglobulin light chain. Renal involvement is common and impaired kidney function is associated with reduced median survival. Autologous stem cell transplantation (SCT) for AL achieves superior response rates compared to chemotherapy alone but patients with end-stage renal disease (ESRD) may be excluded from consideration. A treatment approach consisting of living donor kidney transplantation (LDKTx) followed by autologous SCT was developed for AL with ESRD. Eight patients underwent LDKTx with immediate graft function. Two suffered unanticipated complications post-KTx and died 10 and 3 months later. Two cases of subclinical acute cellular rejection (ACR) and one case of clinical ACR occurred--all reversible with corticosteroid. Six patients had successful stem cell harvests performed and five of these underwent SCT with satisfactory trilineage engraftment. Renal function remained stable following SCT in four and was reduced in one due to infectious and bleeding complications. One patient, who has thus far elected not to undergo SCT, has proteinuria and histologic evidence of recurrent renal amyloidosis. This experience supports the feasibility of sequential living donor KTx and autologous SCT for carefully selected patients with ESRD due to AL.

Autonomic peripheral neuropathy

The autonomic neuropathies are a group of disorders in which the small, lightly myelinated and unmyelinated autonomic nerve fibres are selectively targeted. Autonomic features, which involve the cardiovascular, gastrointestinal, urogenital, sudomotor, and pupillomotor systems, occur in varying combination in these disorders. Diabetes is the most common cause of autonomic neuropathy in more developed countries. Autonomic neuropathies can also occur as a result of amyloid deposition, after acute infection, as part of a paraneoplastic syndrome, and after exposure to neurotoxins including therapeutic drugs. Certain antibodies (eg, anti-Hu and those directed against neuronal nicotinic acetylcholine receptor) are associated with autonomic signs and symptoms. There are several familial autonomic neuropathies with autosomal dominant, autosomal recessive, or X-linked patterns of inheritance. Autonomic dysfunction can occur in association with specific infections. The availability of sensitive and reproducible measures of autonomic function has improved physicians' ability to diagnose these disorders.

Management of paraproteinemic renal disease

PURPOSE OF REVIEW

Paraproteinemic renal diseases comprise a group of renal disorders that are difficult to manage, in part because of subtleties in the clinical presentation and confusion regarding diagnosis and appropriate therapy. Often, nephrologists make the diagnosis of the underlying plasma cell dyscrasia following renal biopsy. This review seeks to provide a greater understanding of the mechanism of disease and recent approaches to the management of patients who have AL-amyloidosis, monoclonal light-chain and light and heavy-chain deposition disease [termed ML(H)CDD], and cast nephropathy. All three renal lesions are caused by deposition of immunoglobulin light chains. This review seeks to provide a greater understanding of the mechanism of disease and recent approaches to the management of these patients.

RECENT FINDINGS

The immunoglobulin light chain takes the center stage in the pathogenesis of AL-amyloidosis, ML(H)CDD and cast nephropathy. Modifications in the variable domain are responsible for the affinity of the light chain for a given segment of the nephron and the subsequent toxic manifestations. Therapy aimed at eradicating the offending clone of plasma cells that secrete the monoclonal light chain should be beneficial, but this hypothesis lacks confirmation. Four nonrandomized studies have now demonstrated clinical benefit, including return of renal function, of high-dose chemotherapy with autologous stem cell transplantation (HDT/SCT) in the treatment of patients who have AL-amyloidosis or ML(H)CDD.

SUMMARY

While randomized trials are lacking, the data support the clinical efficacy of more aggressive treatments designed to reduce the plasma cell clone responsible for these renal disorders.

Immunotherapy in systemic primary (AL) amyloidosis using amyloid-reactive monoclonal antibodies

Heretofore, treatment of patients with primary or light chain-associated (AL) amyloidosis has been directed toward reducing the synthesis of the amyloidogenic precursor protein through conventional or high-dose cytotoxic antiplasma cell chemotherapy. Although such efforts have extended survival, most often the prognosis remains exceedingly poor due to the persistence (or progression) of the pathologic deposits. The development of murine amyloid-reactive monoclonal antibodies (mAbs) has provided another therapeutic approach; namely, passive immunotherapy. These reagents, prepared against human light chain-related fibrils, recognize an epitope common to the beta-pleated structure of AL and other types of amyloid proteins and can effect rapid amyloidolysis when administered to mice injected with human AL amyloid extracts. One such prototypic antibody, the IgG1kappa mAb 11-1F4, has now been chimerized and is undergoing GMP production for an eventual phase I and II clinical trial in patients with AL amyloidosis. Demonstration of the therapeutic efficacy of this amyloid-reactive mAb would provide an important proof-of-principle that this form of immunotherapy also could benefit individuals with other types of inherited or acquired amyloid-associated disease.

Acute renal insufficiency after high-dose melphalan in patients with primary systemic amyloidosis during stem cell transplantation

BACKGROUND

Patients with primary systemic amyloidosis (AL) have a poor prognosis. Median survival time from standard treatments is only 17 months. High-dose intravenous melphalan followed by peripheral blood stem cell transplant (PBSCT) appears to be the most promising therapy, but treatment mortality can be high. The authors have noted the development of acute renal insufficiency immediately after melphalan conditioning. This study was undertaken to further examine its risk factors and impact on posttransplant mortality.

METHODS

Consecutive AL patients who underwent PBSCT were studied retrospectively. Acute renal insufficiency (ARI) after high-dose melphalan was defined by a minimum increase of 0.5 mg/dL (44 micromol/L) in the serum creatinine level that is greater than 50% of baseline immediately after conditioning. Urine sediment score was the sum of the individual types of sediment identified on urine microscopy.

RESULTS

Of the 80 patients studied, ARI developed in 18.8% of the patients after high-dose melphalan. Univariate analysis identified age, hypoalbuminemia, heavy proteinuria, diuretic use, and urine sediment score (>3) as risk factors. Age and urine sediment score remained independently significant risk factors in the multivariate analysis. Patients who had ARI after high-dose melphalan underwent dialysis more often (P = 0.007), and had a worse 1-year survival (P = 0.03).

CONCLUSION

The timing of renal injury strongly suggests melphalan as the causative agent. Ongoing tubular injury may be a prerequisite for renal injury by melphalan as evidenced by the active urinary sediment. Development of ARI adversely affected the outcome after PBSCT. Effective preventive measures may help decrease the treatment mortality of PBSCT in AL patients.

High-dose melphalan with autologous stem cell transplantation after VAD induction chemotherapy for treatment of amyloid light chain amyloidosis: a single centre prospective phase II study

Amyloid light chain (AL) amyloidosis is the result of a clonal plasma cell expansion, in which monoclonal light chains transform to amyloid deposit in various tissues and can lead to organ dysfunction and organ failure. The median survival of patients with AL amyloidosis without therapy is 10-14 months. With high-dose melphalan (HDM) and autologous stem cell transplantation (ASCT), haematological and clinical remission rates of up to 50% of treated patients have been reported from phase II studies. HDM followed by ASCT appears to prolong survival in patients, if haematological remission can be reached. In this phase II study, we evaluated vincristine, adriamycin and dexamethasone (VAD) as induction chemotherapy prior to stem cell mobilization and HDM with ASCT. The regimen was, in general, feasible in patients with AL amyloidosis, but VAD chemotherapy had a considerable World Health Organization (WHO) grade III-IV toxicity (25%) and mortality (7%) rate. VAD pretreatment did not interfere with stem cell mobilization and HDM with ASCT was possible in 86% of patients. The overall treatment efficacy was comparable with reported results of HDM and ASCT without preceding chemotherapy. We could not show an additional benefit of VAD induction in terms of increasing haematological response rate; however the 13% mortality rate after HDM and ASCT in our series was lower than the previous report.

Autologous stem cell transplantation in primary systemic amyloidosis: the impact of selection criteria on outcome

Autologous stem cell transplantation (ASCT) for primary systemic amyloidosis (AL) produces high hematologic and organ responses. However, treatment-related mortality remains high and reported series are subject to selection bias. In all, 48 of 80 amyloid patients referred to our center had AL in the absence of myeloma, 26 of these 48 were deemed transplant candidates and 20 actually underwent ASCT. Transplant-related mortality has fallen from 50 to 20% since January 1999 due to better patient selection and prophylactic measures. Intent-to-treat organ responses were renal (46%), cardiac (25%) and liver (50%). Organ responses in patients who survived transplantation were renal (75%), cardiac (40%) and liver (100%). The 3-year OS post-ASCT was 56% with improved outcome predicted by a better performance status (P=0.08), normal ALP (P=0.08), nephrotic syndrome (P=0.01) and the absence of severe hypotension (P=0.01). The 3-year OS for all referred patients was 44% and this was not significantly better for transplant candidates. Patients with significant hypotension (systolic blood pressure < or =90 mmHg) or poor performance status (ECOG >2) have an exceedingly high treatment-related mortality and should not be transplanted. For those undergoing ASCT, organ response rates appear promising, but conclusive evidence of improved survival for this select group of patients is still lacking and will require randomized trials.

A multicenter phase 2 trial of stem cell transplantation for immunoglobulin light-chain amyloidosis (E4A97): an Eastern Cooperative Oncology Group Study

Stem cell transplantation was introduced as a new therapeutic modality for amyloidosis. The purpose of the current study was to determine the feasibility and toxicity of stem cell transplantation for amyloidosis in a cooperative group setting in which most participating institutions would have limited experience in managing the disorder. A total of 30 patients with biopsy-proven amyloidosis shown to be immunoglobulin light-chain type were enrolled on this trial. The protocol required mobilization of a minimum of 6 x 10(8) mononuclear cells/kg or 5 x 10(6) CD34(+) cells/kg ideal body weight. These targets had to be achieved within seven collections. Patients with advanced hepatic, renal, or cardiac failure were excluded. End points included objective response rate and overall survival. The secondary end point of the protocol was nonhematologic toxicity. Accrual to the study was faster than expected. The overall response rate (hematologic and organ) was 64%, with three treatment-related deaths. Another patient died before day 30 of sudden cardiac death not treatment related. The median follow-up of surviving patients is 30.3 months. Median survival has not been reached. Stem cell transplantation for selected patients with amyloidosis is feasible in a cooperative group setting. A multicenter phase 3 trial of high-dose therapy is indicated.

Improvement in quality of life of patients with AL amyloidosis treated with high-dose melphalan and autologous stem cell transplantation

Treatment of AL amyloidosis patients with high-dose melphalan chemotherapy followed by autologous peripheral blood stem cell transplantation (HDM/SCT) can produce hematologic complete responses (CRs) and improvement in organ function. To determine whether these responses are accompanied by improvement in quality of life (QOL), we employed the Medical Outcomes Study (MOS) 36-item Short Form General Health Survey (SF-36) questionnaire for 544 patients evaluated between 1994 and 2002. At baseline, the scores were significantly lower on all 8 SF-36 scales compared with age-matched population norms: the composite physical component summary (PCS) for the AL patients was 34.5 versus the population norm of 46.8, and the mental component summary (MCS) was 45.0 versus the norm of 51.5. All SF-36 scores improved at 1 year, with the MCS reaching the population norm. The PCS, though improved, was still lower than normal but was greater in the subgroup of patients who achieved a hematologic CR; the PCS normalized at 2 years in these patients. Thus, treatment of AL amyloidosis patients with HDM/SCT produces measurable and sustained improvements in quality of life, particularly in those patients who achieve hematologic CR.

Human Amyloidogenic Light Chains Directly Impair Cardiomyocyte Function Through an Increase in Cellular Oxidant Stress

Primary amyloidosis is a systemic disorder characterized by the clonal production and tissue deposition of immunoglobulin light chain (LC) proteins. Congestive heart failure remains the greatest cause of death in primary amyloidosis, due to the development of a rapidly progressive amyloid cardiomyopathy. Amyloid cardiomyopathy is largely unresponsive to current heart failure therapies, and is associated with a median survival of less than 6 months and a 5-year survival of less than 10%. The mechanisms underlying this disorder, however, remain unknown. In this report, we demonstrate that physiological levels of human amyloid LC proteins, isolated from patients with amyloid cardiomyopathy (cardiac-LC), specifically alter cellular redox state in isolated cardiomyocytes, marked by an increase in intracellular reactive oxygen species and upregulation of the redox-sensitive protein, heme oxygenase-1. In contrast, vehicle or control LC proteins isolated from patients without cardiac involvement did not alter cardiomyocyte redox status. Oxidant stress imposed by cardiac-LC proteins further resulted in direct impairment of cardiomyocyte contractility and relaxation, associated with alterations in intracellular calcium handling. Cardiomyocyte dysfunction induced by cardiac-LC proteins was independent of neurohormonal stimulants, vascular factors, or extracellular fibril deposition, and was prevented through treatment with a superoxide dismutase/catalase mimetic. This study suggests that cardiac dysfunction in amyloid cardiomyopathy is directly mediated by LC protein-induced cardiomyocyte oxidant stress and alterations in cellular redox status, independent of fibril deposition. Antioxidant therapies or treatment strategies aimed at eliminating circulating LC proteins may therefore be beneficial in the treatment of this fatal disease.