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

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.

No regression of renal AL amyloid in monoclonal gammopathy after successful autologous blood stem cell transplantation and significant clinical improvement

BACKGROUND

High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown.

METHODS

In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow.

RESULTS

In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy.

CONCLUSION

Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress.

Prognostication of survival using cardiac troponins and N-terminal pro-brain natriuretic peptide in patients with primary systemic amyloidosis undergoing peripheral blood stem cell transplantation

Primary systemic amyloidosis (AL) is a fatal plasma cell disorder. Pilot data suggest survival is better in patients undergoing peripheral blood stem cell transplantation (PBSCT), but the selection process makes the apparent benefit suspect. We have reported that circulating cardiac biomarkers are the best predictors of survival outside of the transplantation setting. We now test whether cardiac troponins (cTnT and cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) are prognostic in transplant recipients. In 98 patients with AL undergoing PBSCT, serum cardiac biomarkers were measured (cTnT, 98 patients; cTnI, 65 patients; and NT-proBNP, 63 patients). Elevated levels of cTnT, cTnI, and NT-proBNP were present in 14%, 43%, and 48% of patients, respectively. At 20 months median follow-up, median survival has not been reached for patients with values below the thresholds; in patients with values above the thresholds, median survival is 26.1 months, 66.1 months, and 66.1 months, respectively. Our previously reported risk systems incorporating these markers were also prognostic, notably the cTnT/NT-proBNP staging. Using this system, 49%, 38%, and 13% of patients were in stage I, stage II, and stage III, respectively. Determining levels of circulating biomarkers may be the most powerful tool for staging patients with AL undergoing PBSCT.

Therapy for immunoglobulin light chain amyloidosis: the new and the old

An accurate diagnosis of amyloidosis and its subtype classification are essential for disease prognostication and treatment. In primary amyloidosis, overall median survival is approximately 2 years and may be less in patients with cardiomyopathy. Current therapy for primary amyloidosis is suboptimal. Controlled studies suggest that treatment with melphalan and prednisone may provide marginal survival benefit. A more aggressive approach such as autologous hematopoietic stem cell transplantation may offer potential for long-term benefit. Although patients undergoing autologous hematopoietic stem cell transplantation are highly selected, response rates can approach 60%, and patients with amyloidosis who respond to treatment have potential for long-term survival. New treatment modalities that were shown to have antitumor activity in multiple myeloma (high-dose dexamethasone and thalidomide) may also be of therapeutic value in primary amyloidosis. Systemic chemotherapy would not be expected to have any beneficial effect on other forms of amyloid and carries significant risk.

Successful treatment of systemic amyloidosis with hepatic involvement and factor X deficiency by high dose melphalan chemotherapy and autologous stem cell reinfusion

Systemic amyloidosis with hepatic involvement is a rare disorder, which is characterized by the deposits of amyloid fibrils in the liver. The prognosis is poor and the median survival is 13 months. Bleeding problems resulting from coagulopathy frequently complicates systemic amyloidosis. We present two patients with a severe factor X deficiency and hepatomegaly as the presenting abnormalities of systemic amyloidosis. One of the patients was treated with high dose melphalan chemotherapy and autologous stem cell reinfusion, resulting in a normalization of the liver enzyme tests and the factor X level. The diagnosis and treatment of systemic amyloidosis with hepatic involvement and the management of the multifactorial coagulopathy in these cases is discussed.

Superior survival in primary systemic amyloidosis patients undergoing peripheral blood stem cell transplantation: a case-control study

Primary systemic amyloidosis (AL) is a plasma cell dyscrasia resulting in multisystem failure and death. High-dose chemotherapy with peripheral blood stem cell transplantation (PBSCT) has been associated with higher response rates and seemingly higher overall survival than standard chemotherapy. Selection bias, however, confounds interpretation of these results. We performed a case-match-control study comparing overall survival of 63 AL patients undergoing transplantation with 63 patients not undergoing transplantation. Matching criteria included age, sex, time to presentation, left ventricular ejection fraction, serum creatinine, septal thickness, nerve involvement, 24-hour urine protein, and serum alkaline phosphatase. According to design, there was no difference between the groups with respect to sex (57% males), age (median, 53 years), left ventricular ejection fraction (65%), number of patients with peripheral nerve involvement (17%), cardiac interventricular septal wall thickness (12 mm), serum creatinine (1.1 mg/dL [97.24 micromol/L]), and bone marrow plasmacytosis (8%). Sixty-six patients have died (16 cases and 50 controls). For PBSCT and control groups, respectively, the 1-, 2-, and 4-year overall survival rates are 89% and 71%; 81% and 55%; and 71% and 41%. Outside a randomized clinical trial, these results present the strongest data supporting the role of PBSCT in selected patients with AL.

Out-of-hospital cardiac arrest in patients with cardiac amyloidosis: presenting rhythms, management and outcomes in four patients

Primary systemic amyloidosis (AL) is a well-recognized systemic disease, and cardiac amyloidosis accounts for 10% of all nonischemic cardiomyopathies [J S C Med Assoc 97 (2001) 201-206]. The median survival of patients with symptomatic congestive heart failure secondary to cardiac amyloidosis is 4 months [New Engl J Med 336 (1997) 1202-1207; Am J Med 100 (1996) 290-298]. The cause of death in most patients is refractory congestive heart failure or sudden arrhythmic [Mayo Clin Proc 59 (1984) 589-597]. While there are reports of in-hospital arrhythmic deaths in these patients, there are no detailed reports that describe the presentation and management of patients with cardiac amyloidosis who have experienced an out-of-hospital cardiac arrest (OHCA). We describe here our experience with four patients with AL who had an OHCA, including presenting rhythms, interventions, and outcomes.

Fine-needle aspiration of abdominal fat pad for amyloid detection: A clinically useful test?

Fine-needle aspiration of abdominal fat pad (FNAFP) is commonly employed for the diagnosis of systemic amyloidosis, a disease with highly variable clinical manifestations, often presenting difficult patient management problems. We evaluated the role of FNAFP particularly in reference to its clinical usefulness. Pathology reports and clinical histories of 91 consecutive cases of FNAFP with Congo red (CR) staining at The Johns Hopkins Hospital (1999-2000) were reviewed. Major emphases were assessment of the clinical utility of the test, correlation with concurrent or subsequent biopsies, and treatment strategies. The primary indications for FNAFP were monoclonal gammopathy (34%), cardiomyopathy (22%), renal insufficiency (20%), neuropathy (8%), plasma cell dyscrasia (6%), and other conditions (10%). Of the 91 patients who underwent FNAFP, the results were as follows; 20 cases (22%) positive; 62 cases (68%) negative; eight cases (9%) insufficient for diagnosis; and one case (1%) equivocal. Of the 20 positive cases, follow-up biopsies were performed on 11 cases, of which six were positive and five were negative for amyloid by CR. Of the 62 negative cases, follow-up biopsies were performed on 19 cases, 14 of which were negative and five positive for amyloid by CR. A follow-up biopsy on the single equivocal case was positive for amyloid by CR. Twenty-one patients positive for amyloid, based on initial or follow-up biopsies, were managed symptomatically without any specific treatment for amyloidosis. One patient, who was specifically treated for amyloidosis by melphalan and dexamethasone, died 1 wk after therapy. Three patients with multiple myeloma and amyloidosis underwent chemotherapy. We conclude that primary clinical indications for FNAFP for amyloidosis are highly variable. An FNAFP result is often not considered clinically conclusive and is followed by further invasive procedures to detect amyloid (55% of our positive and 31% of our negative FNAFP cases were rebiopsied). The estimated sensitivity and specificity of FNAFP were 75% and 92%, respectively. Overall, the reliance on the results of FNAFP depended on the degree of clinical suspicion of the treating physician. Although in the majority of cases diagnosis of amyloidosis did not alter the treatment strategies, a conclusive positive result helped in ruling out other underlying conditions as the cause of patients' symptoms.

High-dose intravenous melphalan and autologous stem cell transplantation as initial therapy or following two cycles of oral chemotherapy for the treatment of AL amyloidosis: results of a prospective randomized trial

SUMMARY

A prospective randomized trial was conducted to study the timing of high-dose intravenous melphalan and autologous stem cell transplantation (HDM/SCT) in AL amyloidosis. In all, 100 newly diagnosed patients were randomized to receive HDM/SCT, either as initial therapy (Arm-1) or following two cycles of oral melphalan and prednisone (Arm-2). The objectives of the trial were to compare survival and hematologic and clinical responses. With a median follow-up of 45 months (range 24-70), the overall survival was not significantly different between the two treatment arms (P=0.39). The hematologic response and organ system improvements after treatment did not differ between the two groups. Fewer patients received HDM/SCT in Arm-2 because of disease progression during the oral chemotherapy phase of the study, rendering them ineligible for subsequent high-dose therapy. This affected patients with cardiac involvement particularly, and led to a trend for an early survival disadvantage in Arm-2. Hence, newly diagnosed patients with AL amyloidosis eligible for HDM/SCT did not benefit from initial treatment with oral melphalan and prednisone, and there was a survival disadvantage for patients with cardiac involvement if HDM/SCT was delayed by initial oral chemotherapy.

Evaluation of intensive chemotherapy in AL amyloidosis: usefulness of flow cytometric analysis of plasma cells in bone marrow

To investigate whether monoclonal plasma cells in the bone marrow are useful as a therapeutic marker in AL amyloidosis, serial flow cytometry was performed in five patients with this disorder before and after chemotherapy. Four patients were treated with 2 or 3 courses of VAD (vincristine, doxorubicin and dexamethazone) and subsequently with high-dose melphalan followed by auto-PBSCT. The remaining one patient was treated with two courses of VAD alone. Before treatment all patients exhibited a CD19- CD56+ subpopulation, which indicated monoclonal plasma cells, in varying degrees. After treatment all patients showed a decrease in monoclonal plasma cells in accordance with the disappearance of M-protein in serum and/or urine. In two patients treated with VAD followed by auto-PBSCT, polyclonal (CD19+ CD56-) and total plasma cells gradually increased in the follow-up study, while monoclonal plasma cells stayed at less than 0.3% nine months after treatment. No apparent correlation was found between altered maturation of plasma cells and disappearance of M-protein. With respect to easy detection of monoclonal plasma cells producing amyloidogenic M-protein, flow cytometry of bone marrow aspirates is useful and reliable in the follow-up of patients with AL amyloidosis and in the evaluation of the effects of chemotherapy.

Plasma cell dyscrasias and amyloidosis

The plasma cell dyscrasias and amyloidosis are distinct clinical entities that may co-exist. Both disease processes may present with manifestations in the head and neck, making familiarity with these conditions by otolaryngologists essential. Prompt diagnosis and evaluation for systemic disease are crucial in proper treatment planning.

Primary (AL) hepatic amyloidosis: clinical features and natural history in 98 patients

The liver is a common site of amyloid deposition in primary systemic amyloidosis. We reviewed the clinical features and natural history of patients with primary systemic amyloidosis and biopsy-proven hepatic involvement who were evaluated at Mayo Clinic from January 1, 1975, to December 31, 1997. The median age of the study group (68 men; 30 women) was 58.5 years. Seventy-one patients (72%) had involuntary weight loss. Hepatomegaly was found in 79 patients (81%). Eighty-two patients (89%) had proteinuria, and 81 patients (86%) had elevated serum alkaline phosphatase levels. Seventy-six patients (83%) had either a serum or urine monoclonal protein. Before liver biopsy, clinicians considered amyloidosis in the differential diagnosis for only 14 patients (26%). None of our patients experienced hepatic rupture or death due to liver biopsy, and only 4 (4%) bled after liver biopsy. The median survival of the 98 patients was 8.5 months. Predictors of a poor prognosis were congestive heart failure, elevated concentrations of bilirubin, and a platelet count greater than 500 x 109/L. In conclusion, clinicians should consider the diagnosis of primary hepatic amyloidosis in patients who present with involuntary weight loss or hepatomegaly. Other clues to the diagnosis include an unexplained elevated serum alkaline phosphatase level, proteinuria, and evidence for hyposplenism (for example, Howell-Jolly bodies on peripheral blood smear). Liver biopsy was safe. Some patients benefit from systemic chemotherapy.

Amyloid deposition in the oral cavity: a retrospective study and review of the literature

OBJECTIVE

A retrospective study was conducted to investigate the anatomic location and characteristics of amyloid deposition in the oral cavity.

STUDY DESIGN

Seventeen biopsy specimens that were conclusive for a diagnosis of amyloidosis were assessed in terms of their anatomic location and histopathologic characteristics.

RESULTS

Biopsy specimens were received from 13 patients-9 females and 4 males. Six specimens were taken from the buccal mucosa, 4 from the tongue, 3 from the palate, 2 from the gingiva, and 2 from the floor of the mouth. Fifteen of 17 specimens (88%) had amyloid deposition in the subepithelial connective tissue in all locations.

CONCLUSION

On the basis of our pilot data, a previously overlooked intraoral anatomic location, the buccal mucosa, may prove to be of higher diagnostic value than others previously reported in terms of obtaining a diagnosis of amyloidosis. In addition, the manner in which tissue biopsies are conducted for amyloid detection may be altered to create less morbidity.

Immunoglobulin light chain variable (V) region genes influence clinical presentation and outcome in light chain-associated amyloidosis (AL)

Light chain-associated amyloidosis (AL) is a plasma cell dyscrasia in which the secreted monoclonal immunoglobulin (Ig) light chains form amyloid fibrils. There is considerable heterogeneity in clinical presentation, and prognosis of the disease relates to the severity of organ dysfunction induced by amyloid deposits. The mechanisms by which the amyloid fibrils are deposited as well as the predilection for specific organ sites have not been clearly elucidated. This study characterizes the repertoire of immunoglobulin light chain variable genes used by the clonal B cell in AL amyloid patients, and the association of light chain variable region (VL) genes with clinical presentation and outcome is assessed in 58 (32 lambda and 26 kappa) patients. A preferential use of VL germ-line genes was noted for both AL kappa and lambda patients. There was a significant correlation between the use of the Vlambda VI germ-line donor, 6a, and renal involvement as well as the Vlambda III gene, 3r, with soft-tissue AL. The use of a biased VL gene repertoire also correlated with clinical outcome, revealing important trends for predicting prognosis. The use of Vlambda II germ-line genes was associated with cardiac amyloidosis and affected survival adversely. The presence of multiple myeloma also correlated with a poor prognosis. The presence of renal disease, on the other hand, was associated with improved survival. Therefore, identification of the clonal VL gene in AL has important implications in determining clinical outcome.

Incidence and outcome of acute renal failure complicating autologous stem cell transplantation for AL amyloidosis

BACKGROUND

High-dose intravenous melphalan and autologous peripheral blood stem cell transplantation (HDM/SCT) is an effective treatment for AL amyloidosis but is associated with significant toxicity, including the development of acute renal failure (ARF). The incidence and outcome of ARF as a complication of such treatment is not known.

METHODS

All AL amyloidosis patients treated with HDM/SCT at a single institution between July 1, 1994 and May 31, 2000 were included in the analysis unless they were dialysis-dependent prior to treatment. Baseline data were collected prospectively. Treatment-related data were obtained from a prospectively maintained database and medical record review. ARF was defined as either a >/=1 mg/dL increase in serum creatinine or a doubling of serum creatinine to >/=1.5 mg/dL for at least 2 days. Recovery of renal function was defined as a return of serum creatinine to less than or within 0.5 mg/dL of the pretreatment value or the ability to discontinue dialysis initiated as a result of ARF.

RESULTS

ARF occurred in 37 of 173 patients (21%). Initiation of dialysis was required in nine patients (5%). Forty-six percent of patients with ARF, including four of nine who required dialysis, had recovery of renal function. Baseline clinical variables that were independent predictors of transplant-associated ARF included creatinine clearance, proteinuria, and cardiac amyloidosis. Treatment-related variables associated with ARF included melphalan dose and bacteremia. ARF was associated with reduced survival at 90 days but did not have an impact on overall survival at a median follow-up of 2.9 years.

CONCLUSION

ARF is a frequent but often reversible complication of HDM/SCT for AL amyloidosis. Specific clinical and treatment-related factors are associated with the development of this complication.

High-dose intravenous melphalan with autologous stem cell transplantation in AL amyloidosis-associated end-stage renal disease

BACKGROUND

The development of end-stage renal disease (ESRD) is common among patients with amyloid light-chain AL amyloidosis-associated renal disease and survival of these patients is poor. High-dose intravenous melphalan and autologous stem cell transplantation induce remission of the plasma cell dyscrasia in a significant proportion of patients with AL amyloidosis. The efficacy and tolerability of such treatment for patients with AL amyloidosis-associated ESRD are unknown.

METHODS

Between June 1994 and June 2000, 15 patients with AL amyloidosis-associated ESRD were treated with intravenous melphalan (70 to 200 mg/m2) and autologous peripheral blood stem cell transplantation. Clinical and laboratory data were prospectively collected prior to treatment, during the peritransplant period, and at 3 months, 12 months, and annually thereafter. Treatment outcomes and toxicities were compared with 180 non-ESRD patients treated during the study period.

RESULTS

Eight of 15 patients (53%) had a hematologic complete response following treatment. Two patients (13%) died during the peritransplant period. Transfusion requirements were greater and there was a trend toward increased severity of mucositis in the ESRD patients compared with the non-ESRD patients. Median survival for the ESRD patients with a hematologic complete response was 4.5 years. Five patients with hematologic complete response have either undergone or are awaiting renal transplantation.

CONCLUSION

High-dose intravenous melphalan with stem cell transplantation is an effective treatment in selected patients with AL amyloidosis-associated ESRD. Although the toxicity profile is greater in ESRD patients, the treatment offers the possibility of successful renal transplantation if hematologic remission is achieved. This treatment should be considered for patients with AL amyloidosis-associated ESRD.

Tolerability and efficacy of thalidomide for the treatment of patients with light chain-associated (AL) amyloidosis

Thalidomide is an effective therapy for multiple myeloma, although its mechanisms of action remain unclear. Light chain-associated (AL) amyloidosis is a plasma cell disorder related to multiple myeloma, but in AL amyloidosis, fibrillar tissue deposits of clonal immunoglobulin light chains produce organ dysfunction. To test the toxicity and efficacy of thalidomide in AL amyloidosis we initiated a phase I/II trial for patients with AL amyloidosis, most of whom had failed prior therapy with high-dose melphalan and autologous stem cell transplantation. This trial was designed as an individualized 6-month dose-escalation study with reevaluation of bone marrow plasmacytosis and serum and urine monoclonal proteins after 3 and 6 months. Sixteen patients were enrolled in the study with a median age of 62 years (range, 37-70 years). Fourteen patients had renal involvement, 4 had cardiac involvement, 4 had liver involvement, and 2 had predominant soft tissue or lymph node involvement. The median maximum tolerated dose was 300 mg, with fatigue and other central nervous system side effects being the major dose-limiting toxicities. Side effects not frequently reported for other patient populations included exacerbation of peripheral and pulmonary edema and worsening azotemia. In all, 50% of patients experienced grade 3/4 toxicity, and 25% had to discontinue the study drug. No complete hematologic responses were seen, but 25% of patients had a significant reduction in Bence-Jones proteinuria. Thus, while thalidomide has activity in AL amyloidosis, it also has significant toxicity in this patient population.

Beta 2 microglobulin serum levels and prediction of survival in AL amyloidosis

To study the relation between beta 2 microglobulin (beta 2M) and survival in AL amyloidosis, we measured the serum level of beta 2M in 80 patients with AL amyloidosis diagnosed within 1 year of evaluation, who had received no therapy. Patients had a median age of 61 years and 52% were male. Major clinical manifestations were renal disease in 25 patients (31%), cardiomyopathy in 23 patients (29%), and neuropathy or other organ involvement in 32 patients (41%). The beta 2M level, measured by an ELISA assay in serum samples collected at the time of evaluation, ranged from 1.69 to 10 mg/ml (mean = 4.57); in 56% of the patients beta 2M > 4 mg/ml. The patients with a beta 2M < or = 4 mg/ml had serum creatinine levels lower than those with beta 2M > 4 (1.43 vs 2.67 mg/dl; p = 0.02). Survival from study entry was analyzed overall by the level of beta 2M, adjusting for creatinine level and clinical stratum. We found the beta 2M level to be predictive of survival (median survival 16.1 months for beta 2M < or = 4 mg/ml vs 8.0 months for beta 2M > 4 mg/ml, p = 0.044). Thus a beta 2M level less than 4 mg/ml indicated a longer time of survival.

The antisense approach in amyloid light chain amyloidosis: identification of monoclonal Ig and inhibition of its production by antisense oligonucleotides in in vitro and in vivo models

Primary amyloid L chain (AL) amyloidosis is a plasma cell disorder in which depositions of AL cause progressive organ failure. The lack of effective therapies for this fatal disease prompts exploration of newer treatment avenues. We have investigated the application of antisense oligonucleotides (AS) for the inhibition of monoclonal Ig production. The monoclonal L chain was identified by using primers designed for amplifying the human lambda Ig V (Vlambda) region. We demonstrated that AS against L chain complementarity-determining regions inhibited the production of L chain in vitro. RPMI 8226 myeloma cells injected in SCID mice developed s.c. tumors. RT-PCR analysis showed Vlambda mRNA expression in the tumors. In addition, the presence of human Ig in the sera of mice given injection of RPMI 8226 cells was confirmed by ELISA. Administration of AS inhibited the expression of Vlambda mRNA in the s.c. tumors and decreased the concentration of L chain in serum. Therefore, we have shown that it is possible to determine the sequence of Vlambda mRNA and design specific complementary oligonucleotides, suggesting that treatment with Vlambda antisense could represent a rational novel approach to improve treatment outcome in AL amyloidosis.

Toxic megacolon: a life-threatening complication of high-dose therapy and autologous stem cell transplantation among patients with AL amyloidosis

AL amyloidosis is a plasma cell disorder in which tissue deposition of immunoglobulin light chains leads to organ dysfunction. Recent reports of high-dose therapy with autologous stem cell transplantation for amyloidosis suggest higher response rates and extended survival compared to those seen with conventional chemotherapy. However, substantial treatment-related toxicity has been observed. This case series describes our institutional experience with autologous transplantation in four patients with amyloidosis with an emphasis on unique gastrointestinal toxicities, including toxic megacolon.

AL amyloidosis treated with induction chemotherapy with VAD followed by high dose melphalan and autologous stem cell transplantation

High dose melphalan (HDM) followed by reinfusion of autologous blood stem cells (ASCT) has been applied in AL amyloidosis. Vincristine, doxorubicin, and dexamethasone (VAD) rapidly decrease light chain production in multiple myeloma. In a Phase I/II study of VAD followed by HDM and ASCT in AL amyloidosis, toxicity, feasibility, and response to this regimen were evaluated. Over a 5-year period 38 patients with AL amyloidosis were seen of which 12 out of 18 eligible patients participated in the study. VAD induced a distinct clonal response in 50% (6/12) of the patients, but without clinical improvement. In 11 patients HDM and ASCT was applied. Six months after ASCT 78% (7/9) of the surviving patients showed partial clonal response and none responded completely. Clinical condition evidently improved in 67% (6/9) of survivors, whereby clonal response, clinical response, performance score, and SAP scintigraphs were concordant. Therefore a complete clonal response is not a prerequisite for clinical improvement. With median follow-up after ASCT of 25 months, 75% of the study group patients were alive. Mortality was strongly depending on the number of organs involved Patients treated with HDM and ASCT had better survival than those not eligible (P < 0.0005).

Autologous stem cell transplantation for primary systemic amyloidosis

High-dose melphalan with autologous blood stem cell transplantation (SCT) can reverse the disease process in selected patients with primary systemic amyloidosis (AL); however, SCT for AL remains controversial because of the treatment-related mortality in patients with cardiac and multisystem organ involvement. In this review, we briefly discuss recent advances in AL, such as the free light-chain assay and the role of immunoglobulin light-chain variable region germline genes in the disease, and then we discuss the current status of SCT for AL with emphases on patient selection, approaches to stem cell mobilization, and peri-SCT management. It is clear that patients with AL who have advanced amyloid cardiomyopathy or more than 2 major viscera involved with disease are poor candidates for SCT. Therefore, the importance of patient selection cannot be overemphasized, and patients with 1 or 2 involved organs or with early cardiac involvement are usually appropriate candidates for SCT. Because the toxicity of melphalan is dose-related and survival with AL may be age-related, patient age and the extent of organ involvement can provide a basis for patient stratification. We discuss such a risk-adapted approach to melphalan dosing in detail and conclude with a brief overview of current research using SCT to treat patients with AL.

Primary systemic amyloidosis

Primary amyloidosis is a plasma cell dyscrasia in which insoluble immunoglobulin light chain fragments are produced and polymerize into fibrils that deposit extracellularly, causing visceral organ dysfunction and death. The disorder is rare. Its recognition requires understanding the association between nephrotic syndrome, cardiomyopathy, peripheral neuropathy, and hepatomegaly with amyloidosis. The most important screening test for amyloidosis is immunofixation of the serum and urine to detect a monoclonal immunoglobulin light chain. All patients need the diagnosis confirmed histologically. The least invasive source of tissue for amyloid detection is the subcutaneous fat. The most important prognostic factor is whether there is cardiac involvement, which is best assessed by echocardiography with Doppler studies. Therapies used include oral melphalan/prednisone and high-dose corticosteroids. High-dose chemotherapy followed by stem cell reconstitution seems to provide the highest reported response rates. Transplant is associated with unique morbidities not seen in the transplantation of patients with other hematologic malignancies.

Low-dose continuous oral melphalan for the treatment of primary systemic (AL) amyloidosis

Median survival of patients with AL amyloidosis with clinically significant cardiac involvement is 5 months when treated with cyclic melphalan and prednisone. We investigated a regimen of continuous oral melphalan as a single agent for patients with cardiac amyloidosis who were unable to tolerate prednisone or more aggressive chemotherapy. Thirty patients with amyloid cardiomyopathy were treated with continuous oral melphalan. Seven of 13 patients, evaluable after 3-4 months of treatment, achieved a partial haematological response and three achieved a complete haematological response; six patients have survived for > 1 year. This regimen appeared to be effective in inducing haematological responses in patients who received total doses of melphalan > 300 mg.

Bone marrow transplantation for nonmalignant diseases

Bone marrow transplantation (BMT) has emerged as a major therapeutic option for a number of nonmalignant disorders affecting the bone marrow and leading to clinical manifestations most likely affecting distant organs. Disorders such as autoimmune diseases, metabolic disorders, hemoglobinopathies, immunodeficiencies, and others have been the target of high-dose therapy and autologous or allogeneic bone marrow, stem cell, or cord blood transplantation. Successful results have been reported in a large number of these disorders. In most instances the goal of transplantation is to provide sufficient degree of marrow engraftment to allow long-term amelioration of disease phenotype. For many of these disorders, early diagnosis is crucial in achieving the desired results as transplantation becomes difficult when significant end-organ damage sets in. Major unsolved problems, including toxicity of conditioning regimens, graft-versus-host disease, and donor availability, need to be addressed. We attempt to provide a comprehensive review of BMT and discuss unique features of this modality for treatment of nonmalignant disorders.

A multicenter phase II trial of 4'-iodo-4'deoxydoxorubicin (IDOX) in primary amyloidosis (AL)

INTRODUCTION

4'-Iodo-4'-deoxydoxorubicin (IDOX) has been reported to bind to and lead to the catabolism of amyloid deposits. A multicenter study attempted to develop a dosing schedule to confirm those results.

METHODS

Patients with biopsy-proven amyloidosis were required to have a cardiac ejection fraction > 50%, ventricular septal thickness < 20 mm, serum creatinine < 2.5 mg per dL, bilirubin < or = 2.0 mg per dL, neutrophils > 1,500 per microL, and platelets > 100,000 per microL. IDOX was administered intravenously over 1 hour at a dose of 15 mg per m2 once a week for 4 consecutive weeks. This therapy was repeated every 3 months up to 4 times.

RESULTS

Twenty-five previously treated and 15 untreated patients with primary amyloidosis (AL) received therapy. Fifteen patients had > 3 g of protein per day in the urine. Eleven patients had an ejection fraction < 60%. One, 2, 3, 4, and 5 organ systems were involved in 22, 10, 4, 3, and 1 patient, respectively. The median time between diagnosis and initiation of IDOX was 17.4 months. There were 6 responses (15%). Twelve of the patients have died

CONCLUSION

IDOX administered in this protocol was insufficiently active at the current dose.

Immunoglobulin light chain amyloidosis and the kidney

Immunoglobulin light chain amyloidosis and the kidney. Amyloidosis (AL) is a common cause of nephrotic syndrome in nondiabetic, nonhypertensive adults. All adult patients with nephrotic syndrome should have immunofixation of serum and urine as a screen. The finding of a monoclonal protein, particularly of lambda type, should lead to a subcutaneous fat aspirate or bone marrow biopsy to search for amyloid deposits. When the result of either test is positive, a kidney biopsy is unnecessary. The prognosis of patients who have renal amyloidosis depends on the concentration of serum creatinine at presentation and whether an echocardiographic evaluation demonstrates infiltrative cardiomyopathy. Most therapies are directed against the plasma cell dyscrasia present in all patients with AL and can include melphalan and prednisone, high-dose dexamethasone, and, most recently, peripheral blood stem cell transplantation.

Amyloidosis

Amyloidosis is not a single disease but a series of diseases in which there is extracellular deposition of a protein which, although it may be derived from different and unrelated sources, folds into a beta pleated sheet. There have recently been significant advances in elucidating the pathogenesis and in the treatment of this group of disorders. By identifying the source of precursor protein, treatment is aimed at eliminating or reducing the extent of deposition and is tailored for each patient. Early diagnosis is required for the optimal effect of treatment on patient survival and quality of life. An increased awareness among physicians of the spectrum of the disease and tools to aid its diagnosis is of increasing importance.

An overview of the use of high-dose melphalan with autologous stem cell transplantation for the treatment of AL amyloidosis

Primary or AL amyloidosis results from a plasma cell dyscrasia in which fibrillar light chain protein deposition leads to organ failure and death. Standard treatment for AL amyloidosis has been oral melphalan and prednisone. However, this form of treatment modifies the natural history of this lethal disease only marginally, extending median survival from 13 months following diagnosis to 17 months. At Boston University Medical Center, we have developed treatment protocols using high-dose intravenous melphalan with autologous peripheral blood stem cell transplantation (HDM/SCT) to treat AL amyloidosis, and we have treated over 200 patients with HDM/SCT during the past six years. This extensive experience has shown that patients with AL amyloidosis, despite multisystem involvement and compromised organ function can tolerate this aggressive form of treatment. Furthermore, HDM/SCT results in durable hematologic responses in a substantial proportion of patients, and such responses are associated with clinical improvement, decreased amyloid-related organ dysfunction, and prolonged survival. However, toxicity from treatment is high (overall peri-transplant mortality, 14%), particularly for those patients with clinically significant cardiac involvement. For this reason, we believe a multidisciplinary management approach is essential when using HDM/SCT for treatment of AL amyloidosis. Based on our experience, we believe that HDM/SCT is the treatment of choice for patients with AL amyloidosis who have a good performance status and limited cardiac involvement at the time of diagnosis. HDM/SCT offers the best chance for hematologic remission, prolongation of survival, and reversal of amyloid-related disease. At the same time, we believe that HDM/SCT should continue to be examined in the context of clinical trials, directed at developing approaches to broaden the applicability of this therapy by minimizing toxicity and to increase the likelihood of complete hematologic responses.

External-beam radiation therapy in the treatment of diffuse tracheobronchial amyloidosis

Tracheobronchial amyloidosis is characterized by deposits of amyloid in airway walls. No effective treatment is known. We describe a 59-year-old woman who presented with increasing symptoms of airway obstruction due to diffuse deposition of amyloid throughout her tracheobronchial tree. She was treated with external-beam radiation therapy (20 Gy) with marked improvement in her symptoms, effort tolerance, bronchoscopic appearance, and forced expiratory volume in 1 second (1.39 L to 1.97 L [42%]). This improvement was maintained during 21 months of follow-up.

Inhibition of the second phase of amyloidogenesis in a mouse model by a single-dose colchicine regimen

Amyloidogenesis consists of two stages. In the first, amyloid enhancing factor (AEF) is generated, and in the second, deposition of amyloid fibrils occurs. Colchicine is a known inhibitor of amyloidosis of familial Mediterranean fever (FMF) and of mouse experimental amyloidosis, but the timing and mechanism of its effect are still unclear. The aim of this study is to determine whether colchicine inhibits the second phase of amyloidogenesis and to study the time correlate of such an effect. To that end, amyloid was induced in Swiss male mice with AEF and AgNO(3) (an inflammatory stimulus), a method that skips the first phase of amyloidogenesis. Two amyloid induction protocols were used: a standard protocol, in which AEF and AgNO(3) were administered concurrently, and a prolonged protocol, in which the administration of AgNO(3) was delayed by 24 hours or 7 days. To study the inhibitory effect of colchicine on the second phase of amyloidogenesis, a single dose of colchicine (30 microg) was injected intravenously before, during, or after administration of AgNO(3) in both the standard and prolonged amyloid induction protocols. The amount of amyloid deposition in the spleens was determined with the crush-and-smear technique and a 5-grade scale. Colchicine was found to inhibit the second phase of amyloidogenesis. Its best effect was achieved when administered 48 hours after initiation of AgNO(3) injections. The pattern of colchicine-inhibition-in-time in the standard and the prolonged amyloid induction protocols was similar, indicating that colchicine exerts inhibition through its effect on the inflammatory stimulus (AgNO(3)). These findings suggest that (1) colchicine suppresses amyloidogenesis in the late (second) stage and that (2) this suppression is possibly related to the anti-inflammatory effect of colchicine.

The tropism of organ involvement in primary systemic amyloidosis: contributions of Ig V(L) germ line gene use and clonal plasma cell burden

Primary systemic amyloidosis (AL) is a protein conformation disorder in which monoclonal immunoglobulin light chains produced by clonal plasma cells are deposited as amyloid in the kidneys, heart, liver, or other organs. Why patients with AL present with amyloid disease that displays such organ tropism is unknown. This study tested the hypothesis that both the light-chain variable region (Ig V(L)) germ line genes used by AL clones and the plasma cell burden influenced AL organ tropism. To assess the renal tropism of some light chains, an in vitro renal mesangial cell model of amyloid formation was used. With reverse transcription-polymerase chain reaction, Ig V(L) genes were sequenced from 60 AL patients whose dominant involved organs were renal (52%), cardiac (25%), hepatic (8%), peripheral nervous system (8%), and soft tissue and other (7%). Patients with clones derived from the 6a V(lambdaVI) germ line gene were more likely to present with dominant renal involvement, whereas those with clones derived from the 1c, 2a2, and 3r V(lambda) genes were more likely to present with dominant cardiac and multisystem disease. Patients with V(kappa) clones were more likely to have dominant hepatic involvement and patients who met the Durie criteria for myeloma (38%, 23 of 60) were more likely to present with dominant cardiac involvement independent of germ line gene use. In the in vitro model, unlike all other AL light chains tested, lambdaVI light chains formed amyloid rapidly both with and without amyloid-enhancing factor. These data support the hypothesis that germ line gene use and plasma cell burden influence the organ tropism of AL. (Blood. 2001;98:714-720)

High incidence of gastrointestinal tract bleeding after autologous stem cell transplant for primary systemic amyloidosis

Peripheral blood stem cell transplants have been associated with better response rates than conventional chemotherapy in patients with primary systemic amyloidosis. A higher incidence of gastrointestinal (GI) tract bleeding has been observed among amyloidosis patients undergoing peripheral stem cell transplantation. We retrospectively reviewed the medical records of such patients to identify those who had GI tract bleeding in the post-transplant period. Forty-five patients were studied. Nine patients had GI tract bleeding in the post-transplant period. The median post-transplant duration to onset of bleeding was 9.5 days (range 1 to 48 days). Three patients had lower GI tract bleeding, two had upper GI tract bleeding, and four had both. Diffuse esophagitis and gastritis were the most common findings on endoscopy. There were no correlations among the age, platelet nadir, or CD34 count of the graft and the risk of bleeding. Women were more likely to have GI tract bleeding (P = 0.015), as were patients with slow platelet engraftment (P = 0.02). Patients with multiorgan involvement and those on hemodialysis appeared to be at a higher risk of GI tract bleeding. The mean post-transplant hospital stay for those with GI tract bleeding was 37 days compared with 14.5 days for those who did not have GI tract bleeding (P = 0.0047).

Eligibility for hematopoietic stem-cell transplantation for primary systemic amyloidosis is a favorable prognostic factor for survival

PURPOSE

Based on the success of hematopoietic stem-cell transplantation (HSCT) for multiple myeloma, HSCT is being used to treat patients with primary systemic amyloidosis (AL). This article addresses the extent to which eligibility to undergo HSCT is a favorable prognostic feature and explores prognostic factors within the subset of eligible patients.

PATIENTS AND METHODS

The Mayo Clinic amyloid database was queried for all patients with AL seen at the Mayo Clinic from 1983 through 1997 who would have been eligible for peripheral-blood stem-cell transplantation. Inclusion criteria included biopsy-proven amyloid, symptomatic disease, absence of a clinical diagnosis of multiple myeloma, age < or = 70 years, cardiac interventricular septal thickness < or = 15 mm, cardiac ejection fraction more than 55%, serum creatinine < or = 2 mg/dL, and direct bilirubin < or = 2.0 mg/dL.

RESULTS

Median age was 56 years (range, 25 to 70) with 79 (34%) older than 60 years. One hundred patients had early cardiac involvement; 41, hepatic involvement; 167, renal involvement; and 39, nerve involvement. The 229 patients have had a median follow-up of 52 months, and 151 have died. The median survival was 42 months with 5- and 10-year survival rates of 36% and 15%, respectively. Important predictors of survival were size of M-component in 24-hour urine, number of involved organs, alkaline phosphatase, performance score, and weight loss.

CONCLUSION

The same patients who are eligible for HSCT are a good-risk population who do relatively well with chemotherapy (median survival, 42 months), substantially better than the expected median survival of 18 months for all patients with AL. A randomized trial is needed to assess the true effect of HSCT.

Blood stem cell transplantation as therapy for primary systemic amyloidosis (AL)

This study investigated the response rate and toxicity of blood cell transplantation as treatment for primary amyloidosis (AL). Twenty-three patients had stem cells collected between November 1995 and September 1998. Conditioning included melphalan and total body irradiation in 16 and melphalan alone in 4. Three patients did not undergo stem cell infusion because of poor performance status. Two died of progressive amyloid at 1 and 3 months. One patient is alive on hemodialysis. Fourteen males and six females (median age, 57 years) underwent transplantation. Renal, cardiac (by echocardiography), peripheral neuropathy or liver amyloidosis occurred in 14, 12, 3, and 1, respectively. Echocardiography demonstrated an interventricular septal thickness > or = 15 mm in six patients, five of whom died post transplantation. Three patients died of progressive amyloidosis at 7, 7, and 21 months. Thirteen patients are alive with a follow-up of 3 to 26 months. Twelve (60%) fulfilled the criteria of a hematologic or organ response. Severe gastrointestinal tract toxicity was seen in five (25%). We conclude that blood cell transplantation for amyloidosis had a much higher morbidity and mortality compared with transplantation for myeloma. The best results appear to occur in patients with nephrotic syndrome as the only manifestation of their disease.

Restrictive Cardiomyopathy

Of the three major functional categories of cardiomyopathies (dilated, hypertrophic, and restrictive), the restrictive cardiomyopathies (RCMs) are the least common in the Western world, but unfortunately often are associated with the greatest morbidity and mortality. Infiltrative disease of the myocardium (often caused by amyloidosis) is a common cause of RCMs and has a significantly lower long-term survival rate when compared to cardiomyopathies of various other causes. Treatment of the RCM is, in general, difficult and often ineffective. Because of the abnormalities of diastolic filling that are characteristic of this condition, general measures to reduce venous and systemic congestion such as with the use of diuretics, are desirable but often result in an attendant reduction in stroke volume and cardiac output. Digoxin, calcium channel blocking drugs, and beta-adrenergic blocking agents are of limited value, although they may be used with benefit to control the heart rate response in the subgroup of patients with atrial fibrillation. Angiotensin-converting enzyme inhibitors are generally ineffective in RCM. Targeted therapy directed against specific causal entities (such as the use of somatostatin analogues in carcinoid syndrome or iron chelation with desferrioxamine in hemochromatosis) may be more effective than simple symptomatic therapy. Differentiation of RCM from constrictive pericarditis is crucial, since constriction may be treated effectively by surgical removal of the thickened pericardium. A limited number of patients appear to have benefited from novel treatment strategies, such as autologous stem cell transplant in amyloidosis, balloon valvuloplasty of stenotic tricuspid or pulmonary valves in cardiac carcinoid syndrome, and cardiac transplantation. Truly effective therapy for RCM is generally lacking, and the best chance for optimizing the clinical outcome is early detection and aggressive medical treatment in an attempt to maintain the highest possible level of patient function for as long as possible.

Novel approaches to the treatment of primary amyloidosis

Primary (AL, amyloid light-chain) amyloidosis is a plasma cell disorder in which deposits of amyloid light-chain protein cause progressive organ failure. It is important to recognise that amyloidosis is a dynamic process and chemotherapy-induced reduction of the activity of the plasma cell clone reduces the supply of the amyloid precursor protein and can result in a major regression of the deposits. The most common target organ is the kidney and renal amyloidosis manifests as proteinuria or nephrotic syndrome. Proteinuria is seen in three quarters of patients. Amyloid related nephrotic syndrome and renal failure are potentially reversible. Fatigue, congestive heart failure, hepatomegaly, peripheral neuropathy, orthostatic hypotension, carpal tunnel syndrome and macroglossia are other common features. The median survival is one to two years. Conventional-dose melphalan as standard treatment can prolong the median duration of survival by about ten months, but the clinical response rates with improvement of impaired organ function are low. Up-front high-dose chemotherapy with autologous peripheral blood stem cell transplantation is much more effective and can result in a major improvement in the clinical condition of patients. However, the toxicity related to this treatment can be relevant due to impaired organ function. Conventional-dose chemotherapy consisting of vincristine, doxorubicin and dexamethasone or high-dose dexamethasone or interferon-alpha are other possible approaches to treatment. The improvement of patient condition with an effective conventional-dose chemotherapy may increase the tolerability of high-dose chemotherapy and reduce transplantation related problems.

Secondary and Infiltrative Cardiomyopathies

Secondary and infiltrative cardiomyopathies are the least common forms of cardiomyopathy and often are the most difficult to treat. In all cases, efforts should be made to establish a specific diagnosis because the removal or avoidance of the causative agent (eg, alcohol, cocaine, persistent tachycardia) holds the best promise for reversal of ventricular dysfunction. Patients who present with a dilated cardiomyopathy (DCM) should be treated with standard heart failure therapy. However, the "standard" is changing and clinicians need to take heed of results of recent trials establishing the role of beta-blockers, aldosterone, and angiotensin receptor antagonists in addition to the regimen of digoxin, diuretics and angiotensin-converting enzyme (ACE) inhibitors. In contrast, patients who present with a more infiltrative clinical picture often manifest more diastolic dysfunction and need strict volume control to maintain euvolemia. For patients with biopsy-proven myocarditis, immunosuppressive therapy generally should be considered in an effort to maintain and potentially improve ventricular function. Patients with sarcoid heart disease have shown the greatest response to high-dose corticosteroids. Patients with hemochromatosis related cardiomyopathy should be treated with iron chelation therapy and phlebotomy. The role of cardiac transplantation is limited, as most of the secondary and infiltrative causes of cardiomyopathy are associated with an adverse posttransplant outcome. Other surgical options, such as left ventricular assist devices, may offer hope to patients who would otherwise be ineligible for cardiac transplantation. On the horizon, biventricular pacing and treatments targeted at cytokines and hormonal receptors hold the promise of improving symptoms and prolonging survival by counteracting the deleterious effects of these secondary mediators.

Antibody-mediated resolution of light chain-associated amyloid deposits

Primary light-chain-associated (AL) amyloidosis is characterized by the deposition in tissue of monoclonal light chains as fibrils. With rare exception, this process is seemingly irreversible and results in progressive organ dysfunction and eventually death. To determine whether immune factors can effect amyloid removal, we developed an experimental model in which mice were injected with amyloid proteins extracted from the spleens or livers of patients with AL amyloidosis. Notably, the resultant amyloidomas were rapidly resolved, as compared to controls, when animals received injections of an anti-light-chain monoclonal antibody having specificity for an amyloid-related epitope. The reactivity of this monoclonal antibody was not dependent on the V(L) or C(L) isotype of the fibril, but rather seemed to be directed toward a beta-pleated sheet conformational epitope expressed by AL and other amyloid proteins. The amyloidolytic response was associated with a pronounced infiltration of the amyloidoma with neutrophils and putatively involved opsonization of fibrils by the antibody, leading to cellular activation and release of proteolytic factors. The demonstration that AL amyloid resolution can be induced by passive administration of an amyloid-reactive antibody has potential clinical benefit in the treatment of patients with primary amyloidosis and other acquired or inherited amyloid-associated disorders.

Overview of autologous stem cell transplantation

There has been a dramatic increase in the number of autologous peripheral blood stem cell transplants over the last decade. Faster recovery of cell counts, lesser transplant morbidity, shorter hospital stay and reduced cost compared with marrow autografts have been the main advantages of autologous peripheral blood cell over marrow transplants. In this paper we attempt to review the advances in the biology and mobilization of stem cells, and focus on clinical results of autologous peripheral stem cell and marrow transplants for disease specific sites such as breast cancer, myeloma, autoimmune diseases, germ cell tumors, the acute and chronic leukemias, the non-Hodgkin's lymphomas and Hodgkin's disease. We also discuss transplant related complications, gene therapy and the different methods of purging. This review was intended for autologous peripheral stem cell transplants, however, unavoidably, it also discusses autologous marrow transplantation and aspects common to both procedures.

AL-amyloidosis of the kidney initially presenting as minimal change glomerulonephritis

Small amounts of amyloid in kidney biopsy specimens may be missed on routine examination unless specifically targeted. Occasionally, this oversight results in a diagnosis of minimal change glomerulonephritis (MCGN). This misdiagnosis may be facilitated by the fact that typical "minimal changes" with flattening and effacement of the epithelial foot processes can be found in capillary loops directly affected by amyloid deposition as well as in capillary loops of glomeruli with only mild amyloid deposition in the mesangium. Repeatedly, the diagnosis of MCGN had to be corrected to renal amyloidosis when re-examination by special techniques succeeded in detecting even small amounts of amyloid fibrils. We present the case of a previously healthy 49-year-old man who suddenly developed nephrotic syndrome. A first renal biopsy showed MCGN. Proteinuria remained refractory to immunosuppressive treatments, and creatinine clearance deteriorated rapidly. Two years later, a repeat renal biopsy showed AL-amyloidosis. In this case, re-examination of the first biopsy in the light of the final diagnosis again did not show any deposition of amyloid fibrils. We suspect that proteinuria and epithelial podocyte changes in amyloidosis are caused by factors other than deposition of amyloid fibrils itself. Possibly a cytokine release during the early fibril formation leads to abnormalities even before the typical structural changes of renal amyloidosis can be detected. This is analogous to the hypothesis of a circulating factor that leads to proteinuria in focal segmental glomerulosclerosis or the speculation of altered lymphokine expression associated with the development of MCGN in Hodgkin's disease.

Symptomatic ischemic heart disease resulting from obstructive intramural coronary amyloidosis

PURPOSE

Obstructive intramural coronary amyloidosis is an unusual complication of systemic amyloidosis.

SUBJECTS AND METHODS

We review the characteristics of 11 patients seen at the Mayo Clinic (Rochester, Minnesota) from January 1, 1960, to June 1, 1999, with intramural cardiac amyloidosis diagnosed at autopsy or after examination of an explanted heart.

RESULTS

Symptomatic ischemic heart disease resulting from obstructive intramural coronary amyloidosis was found in 11 patients (8 men, 3 women). The mean (+/-SD) age at the diagnosis of primary amyloidosis was 62 +/- 12 years. All patients had angina pectoris; angina was the presenting symptom of primary amyloidosis in 6 patients. Unstable coronary syndromes occurred in 7 patients and congestive heart failure in 8. New electrocardiographic abnormalities after the development of angina were common and included ischemic changes, bundle branch block, and dysrhythmias. Low voltage was seen in only 2 patients. All 7 patients who underwent coronary angiography had normal or clinically insignificant findings. Endomyocardial biopsy was performed on 4 patients; amyloid was found in 3 patients, none of whom had obstructive intramural coronary amyloidosis. The diagnosis of obstructive intramural coronary amyloidosis with associated myocardial injury was established only at autopsy or after examination of the explanted heart after cardiac transplantation. The mean time to death or cardiac transplantation after symptoms of cardiac ischemia developed was 18 +/- 20 months.

CONCLUSIONS

The diagnosis of ischemic heart disease resulting from obstructive intramural coronary amyloidosis is difficult to establish before death or cardiac transplantation. Although the condition has a poor prognosis, its accurate recognition may have therapeutic implications, because some patients may benefit from treatment, including systemic chemotherapy or cardiac transplantation.

Hematopoietic cell transplantation for primary systemic amyloidosis: what have we learned

Dose-intensive therapy with hematopoietic cell transplantation is effective at reversing AL amyloidosis but is not without risk. Guidelines have been developed for patient selection in order to maximize benefit and minimize treatment-related mortality. Identification of a patient's clonal germline light chain variable region gene may become relevant to patient selection, and development of less morbid approaches to stem cell mobilization and collection would be helpful. While there is room for discussion regarding the design of future therapeutic trials, it is reasonable to attempt to improve the complete response rate for good risk patients by continuing efforts on the phase II level. Attempts to improve outcomes for patients with symptomatic cardiac or advanced multisystem disease may require serial solid organ and stem cell transplantation as well as the development of less toxic approaches using lower doses of melphalan, improved supportive care measures and specific organ-system prophylaxis. If outcomes can be improved, issues related to clonotypic contamination of stem cells will need to be revisited.