Combined use of bortezomib, cyclophosphamide, and dexamethasone induces favorable hematological and organ responses in Japanese patients with amyloid light-chain amyloidosis: a single-institution retrospective study

Waldenström macroglobulinemia treatment algorithm 2018

Waldenström macroglobulinemia is often an indolent disorder, and many patients are candidates for observation with careful monitoring. For symptomatic patients, one must distinguish between those patients whose symptoms are related to immunologic manifestations associated with the IgM monoclonal protein and those that have symptoms related to progressive marrow and nodal infiltration with lymphoplasmacytic lymphoma. In Waldenström macroglobulinemia, the driver for therapy in the majority of patients is progressive anemia, secondary to bone marrow replacement by lymphoplasmacytic lymphoma. Recent introduction of MYD88 mutational analysis has been very useful for diagnostic purposes but is unclear what effect it might have on the prognosis or response rate to therapy. An algorithm is provided on the management of asymptomatic individuals and the sequence used for chemotherapeutic intervention of symptomatic patients.

Direct Factor X sequestration by systemic amyloid light-chain amyloidosis

We present a lymphoplasmacytic lymphoma patient with Factor X (FX) deficiency. Despite the absence of FX inhibitor, the administration of fresh frozen plasma and anti‐inhibitor coagulant complex did not increase the FX level. The autopsy showed that massive amyloid depositions to multiple organs and FX existed in union with amyloidosis.

Nationwide Survey of 741 Patients with Systemic Amyloid Light-chain Amyloidosis in Japan

Objective To retrospectively investigate the clinical manifestations of systemic amyloid light-chain (AL) amyloidosis in Japanese patients and the treatment strategy for the condition. Methods We conducted a survey of Japanese AL amyloidosis patients, who were treated between January 1, 2012, and December 31, 2014. Results A total of 741 AL amyloidosis patients were included in this study (436 men and 305 women; median age: 65 years old, range: 31-93). The most frequently affected organ was the kidneys (n=542), followed by the heart (n=252), gastrointestinal (GI) tract (n=164), autonomic nervous system (n=131), liver (n=71), and peripheral nervous system (n=71). Diagnostic findings were most commonly detected in the GI tract (upper GI tract: 350 cases, lower GI tract: 167 cases), followed by the bone marrow and kidneys. An abdominal fat-pad biopsy was only conducted in 128 patients. Autologous stem cell transplants (ASCTs) and bortezomib were used to treat 126 and 276 patients, respectively. Conclusion The clinical features of Japanese patients with systemic AL amyloidosis are similar to those reported previously for cases in the US and Europe. Regarding treatment, a significant number of ASCTs were performed in Japan as well as in Western countries. Surprisingly, a marked number of patients received bortezomib as a treatment for AL amyloidosis.

Stem cell transplantation compared with melphalan plus dexamethasone in the treatment of immunoglobulin light-chain amyloidosis

BACKGROUND

Autologous stem cell transplantation (SCT) is a common management strategy for select patients with immunoglobulin light-chain amyloidosis, but no trials have documented improved overall survival.

METHODS

Eighty-nine patients with biopsy-proven immunoglobulin light-chain amyloidosis were allowed to select treatment with melphalan plus dexamethasone (n = 34) or SCT (n = 55); all patients were transplant eligible. Treatment preference resulted in imbalanced study arms. Patients who selected SCT were younger, more frequently had an Eastern Cooperative Oncology Group performance status score less than 2, had lower-stage amyloidosis, and had a lower incidence of cardiac amyloidosis.

RESULTS

Patients receiving melphalan plus dexamethasone had a 3-year progression-free survival rate of 29.1% and an overall survival rate of 58.8%. Patients undergoing SCT had a 3-year progression-free survival rate of 51.7% and an overall survival rate of 83.6%. An attempt to match patients between the 2 arms in terms of risk produced 24 matched triplet sets (2 SCT patients for each melphalan-dexamethasone patient); there was no difference in hematologic response, but there was better survival after autologous SCT. A propensity score-matched analysis of the cohorts (melphalan plus dexamethasone vs SCT) showed an overall mortality hazard ratio of 2.56 (P < .01).

CONCLUSIONS

Although the study had limitations, similar hematologic responses and improved survival were observed after SCT versus melphalan plus dexamethasone. Cancer 2016;122:2197-205. © 2016 American Cancer Society.

Successful Treatment of Amyloid Light-chain Amyloidosis in a Charcot-Marie-Tooth Disease Patient with Lenalidomide, Cyclophosphamide, and Dexamethasone

A 70-year-old woman with Charcot-Marie-Tooth disease (CMT) suffered from nephrotic syndrome and a renal biopsy revealed non-AA amyloid depositions that contained immunoglobulin light chain λ. Her serum λ free LC was elevated to 80.8 mg/L and she was diagnosed with primary amyloid light-chain (AL) amyloidosis. She was subsequently treated with lenalidomide, cyclophosphamide, and dexamethasone (RCD). After 14 cycles of RCD, she achieved complete remission. Her serum albumin levels gradually normalized to 3.1 g/dL. No exacerbation of neurologic symptoms related to CMT was observed. Thus, RCD may be a well-tolerated and effective regimen for treating AL amyloidosis in patients with CMT disease.

Immunoglobulin Light Chain Systemic Amyloidosis

Immunoglobulin light chain amyloidosis (AL) is a rare, complex disease caused by misfolded free light chains produced by a usually small, indolent plasma cell clone. Effective treatments exist that can alter the natural history, provided that they are started before irreversible organ damage has occurred. The cornerstones of the management of AL amyloidosis are early diagnosis, accurate typing, appropriate risk-adapted therapy, tight follow-up, and effective supportive treatment. The suppression of the amyloidogenic light chains using the cardiac biomarkers as guide to choose chemotherapy is still the mainstay of therapy. There are exciting possibilities ahead, including the study of oral proteasome inhibitors, antibodies directed at plasma cell clone, and finally antibodies attacking the amyloid deposits are entering the clinic, offering unprecedented opportunities for radically improving the care of this disease.

Phase 1 study of bortezomib in combination with melphalan and dexamethasone in Japanese patients with relapsed AL amyloidosis

We performed a phase 1 study to evaluate the safety and feasibility of bortezomib (BOR) with melphalan and dexamethasone (BMD) in patients with light chain amyloidosis (AL) without severe cardiac failure. Patients received BOR on a twice-weekly schedule (days 1, 4, 8, and 11 of 28-day treatment cycles) at planned doses of 1.0 (dose level 1) and 1.3 (dose level 2) mg/m(2) in combination with melphalan 8 mg/m(2) on days 1-4 and dexamethasone 20 mg on days 1, 2, 4, 5, 8, 9, 11, and 12. Dose-limiting toxicity (DLT) was evaluated at the end of cycle one, and treatment was continued for four cycles. Six patients were enrolled at dose level 1, and one showed DLT (grade 3: herpes zoster). Further 3 patients were enrolled at dose level 2, and none experienced DLT. Thus, the maximum tolerated dose was defined as BOR doses of 1.3 mg/m(2) for the twice-weekly schedule. A total of 32 cycles of BMD therapy were given, and the most common hematologic toxicity was thrombocytopenia (47%). Peripheral neuropathy was the most common non-hematologic toxicity (16%). We demonstrated that BMD is safe and tolerable for Japanese AL patients without severe cardiac damage.

CLINICAL TRIAL REGISTRATION

UMIN000006604.

Treatment of Immunoglobulin Light Chain Amyloidosis: Mayo Stratification of Myeloma and Risk-Adapted Therapy (mSMART) Consensus Statement

Immunoglobulin light chain amyloidosis (AL amyloidosis) has an incidence of approximately 1 case per 100,000 person-years in Western countries. The rarity of the condition not only poses a challenge for making a prompt diagnosis but also makes evidenced decision making about treatment even more challenging. Physicians caring for patients with AL amyloidosis have been borrowing and customizing the therapies used for patients with multiple myeloma with varying degrees of success. One of the biggest failings in the science of the treatment of AL amyloidosis is the paucity of prospective trials, especially phase 3 trials. Herein, we present an extensive review of the literature with an aim of making recommendations in the context of the best evidence and expert opinion.

A mouse model recapitulating human monoclonal heavy chain deposition disease evidences the relevance of proteasome inhibitor therapy

Randall-type heavy chain deposition disease (HCDD) is a rare disorder characterized by glomerular and peritubular amorphous deposits of a truncated monoclonal immunoglobulin heavy chain (HC) bearing a deletion of the first constant domain (CH1). We created a transgenic mouse model of HCDD using targeted insertion in the immunoglobulin κ locus of a human HC extracted from a HCDD patient. Our strategy allows the efficient expression of the human HC in mouse B and plasma cells, and conditional deletion of the CH1 domain reproduces the major event underlying HCDD. We show that the deletion of the CH1 domain dramatically reduced serum HC levels. Strikingly, even with very low serum level of truncated monoclonal HC, histologic studies revealed typical Randall-type renal lesions that were absent in mice expressing the complete human HC. Bortezomib-based treatment resulted in a strong decrease of renal deposits. We further demonstrated that this efficient response to proteasome inhibitors mostly relies on the presence of the isolated truncated HC that sensitizes plasma cells to bortezomib through an elevated unfolded protein response (UPR). This new transgenic model of HCDD efficiently recapitulates the pathophysiologic features of the disease and demonstrates that the renal damage in HCDD relies on the production of an isolated truncated HC, which, in the absence of a LC partner, displays a high propensity to aggregate even at very low concentration. It also brings new insights into the efficacy of proteasome inhibitor-based therapy in this pathology.