Experience of AL in Latin America Open Access

In the last issue of Blood Global Hematology, Galvez et al¹ reported on the outcomes of 33 patients with confirmed AL treated at a private tertiary care center in Colombia within a 13-year period. Two-thirds of the patients had multiple myeloma. Typing relied on immunohistochemistry, as there was no access to mass spectrometry. In addition, cardiac involvement was evaluated by echocardiography and biomarkers, with limited access to magnetic cardiac resonance. In this low number of patients, Mayo stages III to IV were found in <20%, raising awareness about the misdiagnosis or early death of patients with more severe disease.

The median time from diagnosis to treatment initiation was 11 days, suggesting that AL in patients with concomitant multiple myeloma is probably easier to identify. However, the wide range (up to 323 days) indicates significant delays in certain cases that merit further investigation.

First-line therapy was CyBorD (cyclophosphamide, bortezomib, dexamethasone) in 63% of cases, whereas 18% of patients received daratumumab, lenalidomide, or thalidomide plus bortezomib therapies. This is consistent with the time frame before approval of daratumumab for AL. It would also be interesting to know whether, in the last period, more patients have access to daratumumab, at least in private institutions. The reasons for the low rate of autologous transplantation (24%) in a cohort in which 66% had multiple myeloma merit further details. Were the patients not eligible due to AL or is there a delay or shortage in accessing transplantation?

The median overall survival (OS) was long (66 months; interquartile range [IQR], 30-119). Survival dropped to 35 months (IQR, 10-63) in those with cardiac involvement; as expected, patients who underwent transplantation lived longer than those who did not undergo transplantation, probably influenced by selection criteria and the high incidence of myeloma in the cohort.

Amyloidosis (AL) is a rare disease frequently underdiagnosed due to its subtle symptoms and overlap with other diseases. Since the Andromeda trial,² the standard treatment is a combination of daratumumab, bortezomib, cyclophosphamide, and dexamethasone. However, this regimen is not uniformly accessible across Latin America, a region where diagnosis and treatment are particularly challenging. Regional data are needed to identify care gaps and improve outcomes.

Although limited in number, the studies published about AL in Latin America are important for understanding the reality in the region.^3-7 There are publications from Chile, Argentina, and Brazil. The Chilean study reported 42 patients with a median OS of 19 months.³ The Argentine study reported 90 patients in a 9-year period, 70 of whom received treatment, with a median OS of 5 years.⁴ The Brazilian study reported 97 patients with an OS of 18.5 months and 8.6 months for those with cardiac involvement. In India, a study reported on 13 patients with AL and cardiac involvement, with a median OS of 18 months.⁵ A systematic review conducted in India revealed that this condition is underdiagnosed and that reports are mainly based on retrospective studies.⁸ 

In a report from a Colombian study,⁴ many similarities were found with previous studies carried out both in Latin America and in countries such as India and Turkey,⁹ primarily single-center experiences with a limited number of patients and all being retrospective studies. Furthermore, among the differences, we observe that OS is better for both the entire cohort and patients with cardiac involvement compared with that in all the previously mentioned studies, except for the Argentine study reporting a similar OS for the entire population, although data on patients with cardiac involvement were not available.

These data, although from a small number of patients and with the expected deficiencies of a retrospective and unicentric study, far from being disappointing, leave us with the hope that AL is becoming more visible in the region and with the commitment to new and larger multicentric studies to have a more global perspective. It would be valuable to include detailed response and toxicity data and conduct a prognostic factor analysis. This would not only validate the findings in a larger and more diverse population but also help refine risk stratification and treatment decisions.

Disseminating data on the reality of AL in the region is important as it will allow to identify areas for diagnostic and therapeutic improvement, a pending debt in Latin America.

Conflict-of-interest disclosure: The authors declare no competing financial interests.