Characterization and prognostic implication of delayed complete response in AL amyloidosis

State-of-the-art review on AL amyloidosis in Western Countries: Epidemiology, health economics, risk assessment and therapeutic management of a rare disease

Amyloidosis is the term to define a broad array of rare protein misfolding syndromes. Among them, light chain (AL) amyloidosis is the most common, affecting roughly 10 people per million/year. The core purpose of the present literature review is to shed light on the academic and clinical knowledge on the condition, encompassing its i) epidemiology, ii) economic burden, and iii) quality of life consequences. The areas of interest are Europe and North America. Literature search was primarily performed on Embase® and finally integrated with additional, deemed eligible, sources. Pre-defined PICOS criteria were employed for the inclusion and exclusion processes. A total of 64 studies were comprehensively included in the current literature review as compliant with the inclusion criteria. The results were presented according to the outcomes of interest and eventually triangulated and compared to available literature studies. A broad picture on the main aspects of AL amyloidosis is delivered.

Fixed duration vs. prolonged duration treatment after first line therapy in patients with systemic light chain amyloidosis

BACKGROUND

The main objective of treatment in systemic light chain amyloidosis (AL amyloidosis) is to achieve the best hematological response. Deeper responses are associated with better organ responses and survival. In this study, we analysed the efficacy of prolonged duration treatment after first line in patients with AL amyloidosis.

METHODS

Retrospective analysis that included patients older than 18 years with AL amyloidosis. We excluded patients with more than 30% marrow plasmacytosis or concurrent multiple myeloma. Two cohorts identified accordingly if they received or not prolonged treatment after the first line. Survival analysis regarding progression free survival (PFS) and overall survival (OS) estimated with Kaplan-Meier and comparisons between groups with log-rank.

RESULTS

Thirty-eight patients were included in the analysis with a median age of 55 years. Twenty-one patients received prolonged duration treatment and 17 did not. In the prolonged duration group, after a median duration of 12 months, the median PFS was 58.8 months. In the fixed duration treatment group, PFS was 30.6 months. The difference was significant with p = .0045 favouring prolonged duration treatment. Organ response was sustained for a longer period in the prolonged duration treatment group. For OS, the difference was not significant.

CONCLUSIONS

Prolonged duration treatment in patients with systemic light chain amyloidosis correlated with better PFS and deeper organ responses. Prospective studies are needed to analyse this further.

Dealing With High-Risk AL Amyloidosis Patients: A Single Hematologic Center Experience

PURPOSE

To assess the feasibility and the results of Bortezomib-based treatment of "high-risk" AL-amyloidosis patients in a hematology ward.

METHODS

We report on 52 high-risk amyloidosis patients treated with first-line bortezomib-based chemotherapy.

RESULTS

At day 30 from the beginning of the therapy, 23 patients (44%) achieved a hematological response (complete response plus very good partial response); 14 patients (27%) achieved a partial response; 15 patients (29%) were non-responders. After a median follow-up of 28.5 months, the survival rates were 18/23 (78%) for responders; 9/14 (64%) for partial responders and 3/15 (20%) for nonresponders with a median overall survival of 43, 24 and 11 months, respectively (log-rank test: P < .001). NHYA class I-II, NTproBNP < 6500 ng/L, the hematologic response, and the partial hematological response at day 30 independently predicted the survival. There has been no significant difference (P = .173) in survival between revised Mayo stage III and IV patients although there was a trend toward a better prognosis for Mayo stage III. A suboptimal hematological response at day 30 allowed a later organ response in 12/14 patients (85%) even without therapy change and no modification of the hematological status.

CONCLUSIONS

These results show that high-risk AL-amyloidosis patients can be managed safely and effectively in a hematology ward. A partial hematologic response may herald a later better response, organ response, and can allow a subsequent second-line therapy and a good survival.