SMOLDERING MULTIPLE MYELOMA IN LATIN AMERICA

Introduction: Smoldering multiple myeloma (SMM) is an asymptomatic clonal plasma cell disorder with a prevalence of 0.5% in the > 40 yrs population. Effort has been made to characterize these patients in the real world. There is scarce data about SMM in Latin America (LA) and we aimed to characterize SMM in this region. Methods: A consortium between the Brazilian and Latin America myeloma study groups (GBRAM-GELAMM) were stablished to conduct a retrospective cohort study of SMM cases diagnosed from 2015 to 2023. Data collected included demographics, diagnostic and prognostic tools. We also captured data of progression to MM and SMM management. Progression-free survival (PFS) and overall survival (OS) were calculated. Results: A total of 247 pts had been included, from 35 different institutions belonging to eight different countries. Ninety-five (38.5%) of pts were followed in the public health sector (PS). The median age at diagnosis was 64 (34-90) yrs and 158 (64%) patients were female. The immunoglobulin isotype were IgG, IgA and light chains in 158 (64%), 70 (28.3%) and 14 (5.7%), respectively. Regarding exams availability, 210 (85%) pts had FLC analysis, 111 (44.9%) pts had a total body MRI or PET-CT and 106 (42.9%) pts had low radiation total body CT. A total of 191 (77.3%) pts had all the 20-2-20 criteria available from whom 74 (38.7) were low risk, 61 (32.9%) were intermediate risk, 56 (29.3) were higk risk. From the total of patients included 59 (23.9%) progressed, from whom 10 (4%), 14 (5,7%),18 (7.3%) and 17 (28.9%) were low, intermediate, high risk and unknow data, respectively. Median time to progression was 34 (3-136) months, and 11 patients had progressed over 12 months from diagnosis. Chance to progression considering the risk factors from 20-2-20 criteria was identified but not significant (p = 0.08). Thirteen (5%) pts died or lost follow-up. The median follow-up was 42.2 months. Discussion/Conclusion: This is the first cohort with representation of patients with SMM in LA. Although the majority of MM patients in LA are followed in the public sector, only 40% of the SMM cases in the present study belong to this sector, reveling the access difficult to diagnosis tools for SMM cases in the public sector. The majority of pts did have access to CT, MRI, PET, FLC assay and bone marrow study, which we interpret as a correct identification of SMM criteria in our cases. The 20-2-20 criteria works for the study population stratification although no statistical difference was observed, possibly due to the number of cases and/or shot follow-up

CENTRAL NERVOUS SYSTEM INVOLVEMENT IN AGGRESSIVE ATLL: CAN WE PREDICT THE RISK IN A DEVASTATING COMPLICATION? EPIDEMIOLOGY AND CLINICAL FEATURES FROM LATIN AMERICA. A COLLABORATIVE STUDY FROM GRUPO DE ESTUDIO LATINO-AMERICANO DE LINFOPROLIFERATIVO (GELL) & T-CELL BRAZIL PROJECT (TCBP)

Introduction: Adult T-cell leukemia/lymphoma (ATLL) is a mature, peripheral T-cell neoplasm caused by HTLV-1 and its lifetime risk is estimated as 4-7% among HTLV-1 carriers. Acute and lymphoma subtypes are highly aggressive diseases, characterized by shorter survival rates and a high risk of central nervous system involvement (iCNS) compared to other peripheral T-cell lymphomas. Currently, the treatment of ATLL remains a challenging. Our recent study on PTCL epidemiology and outcomes in Latin America (Thais et al. 2023 ASH Meeting) highlighted ATLL (18%) as the second most frequent subtype of PTCL, likely influenced by our distinct viral epidemiology. Objective: It is to assess the prevalence, clinical features, risk factors, and outcomes of iCNS in ATLL in Latin America. Methodology: Patients (pts) aged ≥18 years with newly diagnosed ATLL from GELL (n = 208, 2000-2023, retrospective) and TCBP (n = 83, 2015-2022, ambispective). Overall survival (OS) and progression free survival (PFS) were our endpoints. REDcap Platform (by Vanderbilt) was used to collect and store data, whereas for statistical analysis IBM-SPSS v.24. This trial is registered at Clinical trials (NCT03207789). Results: It was enrolled 291 pts, the prevalence of iCNS in ATLL was 7.9% (23/291), considering only aggressive forms (acute 40% and 60% lymphomatous). Pts'characteristics were similar between those without and with iCNS. There was a high frequency of advanced stage (90% vs 82%); ECOG ≥ 2 (45% vs 43%); B symptoms (74% vs 56%); elevated LDH (84% vs 78%); and IPI ≥3 (82% vs 65%) in the iCNS group. Treatment was heterogeneous including: IFN+AZT (74%) for acute subtypes, and CHOP (52%), CHOEP (26%) and EPOCH (2%), for lymphoma subtypes. Less than 30% of both groups achieved complete response at end of first treatment. Two clinical features were identified as possibly associated to iCNS: median age at diagnosis (55 [20-95] vs 44 [23-65]; p < 0.0001) and extra nodal involvement ≥ 2 (32% vs 65%, p = 0.005). The entire cohort of ATLL had 60- month OS and PFS of 16% [95% CI: 12-20%] and 9% [95% CI: 5-13%]; with median time of OS and PFS of 7 months (6-9) and 5 months (4-6). iCNS did not have an impact on survival outcomes (60 months OS 14% iCNS (n = 23) vs 16% no iCNS (n = 254), p = 0.91; PFS 12% vs 9% no iCNS, p = 0.61;) despite being a devastating complication. Outcomes in pts with lymphoma subtypes were slightly better than acute (60 months OS 19% vs 10%, p < 0.0001; PFS 12% vs 5%, p < 0.0001, respectively). Conclusion: Unlike other lymphoma subtypes, iCNS in ATLL does not appear to significantly impact outcomes. This paradoxical finding underscores the complexity of ATLL and may reflect the limitations of existing treatment options and the absence of standardized therapeutic protocols for this aggressive malignancy. The lack of significant survival difference, despite the severity of iCNS, points to an urgent need for innovative therapies and more effective treatment strategies. Our analysis identified median age at diagnosis and extranodal involvement as potential risk factors for iCNS, suggesting avenues for future prospective studies to further elucidate their role in disease progression. Given the high prevalence of ATLL in Latin America, there is a unique opportunity to advance our understanding of this disease through region-specific research. Collaborative efforts in this region could pave the way for breakthroughs in the management of ATLL and potentially offer insights applicable on a global scale