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

Ten-year follow-up after autologous stem cell transplantation of a patient with immunoglobulin light-chain (AL) amyloidosis with deposits in the heart, liver and gastrointestinal tract

The prognosis in amyloid light chain (AL)-amyloidosis and multiorgan involvement is poor, with a high-treatment-related mortality after high-dose melphalan and autologous stem cell transplantation (HDM/SCT). Some patients, however, might benefit from the therapy. We report a case of cardiac AL-amyloidosis with multiorgan involvement where the progressive cardiomyopathy was halted after successful treatment with HDM/SCT in 2001. The patient is in an excellent cardiac condition with a good quality of life, receiving treatment with angiotensinogen receptor blockers and a flexible diuretics regimen at follow-up after 10 years.

[52 year-old patient with severe heart failure due to multiple myeloma]

Cardiac amyloidosis represents a prognostically relevant comorbidity in multiple myeloma. We report the case of a patient in whom severe heart failure symptoms as a consequence of cardiac AL-amyloidosis resolved after tandem high-dose melphalan therapy followed by autologous blood-stem cell transplantation. Partial regression of cardiac amyloid deposits and improvement of cardiac function were objectified.

Early intensification and autologous stem cell transplantation in patients with systemic AL amyloidosis: a single-centre experience

Primary systemic amyloidosis (AL amyloidosis) continues to have a very poor prognosis. Most therapeutic strategies remain unsatisfactory. Conventional chemotherapy is known to offer at best only moderate efficacy. Several studies have yielded higher complete response rates after high-dose chemotherapy and autologous stem cell transplantation (ASCT) in addition to improving outcomes in a subgroup of patients. However, the superiority of an intensive approach in AL amyloidosis has not been confirmed in a randomised trial. The precise role of ASCT remains unclear. We report our experience in 16 patients diagnosed with AL amyloidosis and treated in a multidisciplinary approach with high-dose melphalan and ASCT. Median age was 59 (39-71) years. The kidneys were predominantly affected in 75% of cases; two or more organs were affected in 38%. Median time from diagnosis to transplantation was 2 (1-4) months. Three patients (19%) developed acute renal failure and required transient dialysis. Transplant-related mortality was 6% after 100 days. Haematological complete response (CR) was obtained in nine (56%) and organ response in six (38%) patients. Nine out of 12 patients (75%) with kidney involvement exhibited a sustained clinical benefit at 12 months. Half of all the patients (n = 8) were alive after a median follow-up of 33 months, including two in continuous CR. This suggests that high-dose chemotherapy and ASCT are still valid treatment options in AL amyloidosis and that a significant number of patients with renal involvement might benefit from this approach.

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.

Multiple myeloma-associated AL amyloidosis: is a distinctive therapeutic approach warranted?

The natural history of multiple myeloma (MM) was revolutionized by the introduction of haematopoietic stem cell transplantation to the treatment armamentarium of this disease. Defined subgroups of MM patients (such as the elderly or dialysis-dependent) have required an individualized approach in order to minimize the transplant-related mortality. Little, however, is known about the management of 12-30% of MM patients with coexistent AL amyloidosis as the amyloidopathy is often overlooked and when recognized these patients commonly are excluded from clinical trials. While occult amyloidosis appears to have no impact on the toxicity and outcome of MM patients, the presence of symptomatic amyloidopathy clearly worsens their prognosis. Use of induction chemotherapy drugs that can cause further damage to the heart (Adriamycin), nervous system (Vincristine) or kidneys should be avoided as should lengthy delays in proceeding to autograft. Further, refining the transplant eligibility criteria for this subgroup of patients with co-existent amyloidopathy to include the number of organs involved and the degree of cardiac involvement (NYHA class, Troponins and NT-pro-BNP levels) along with melphalan dose-adjustment will minimize the treatment-related toxicity and mortality and possibly allow a reversal of the organ damage induced by the amyloidogenic light chain.