In-depth characterization of NK cell markers from CML patients who discontinued tyrosine kinase inhibitor therapy.

Introduction: Treatment-free remission (TFR) in patients with chronic myeloid leukemia in chronic phase is considered a safe option if suitable molecular monitoring is available. However, the question arises as to which factors can contribute to the maintenance of TFR, and immunologic surveillance of the remaining leukemic cells is believed to be one of them. Argentina Stop Trial is an open-label, single-arm, multicenter trial assessing TFR after tyrosine kinase inhibitors interruption, that after more than 4 years showed a successful TFR rate of 63%. Methods: In this context, we set up an immunological study by flow cytometry in order to analyze specific NK cell subsets from peripheral blood patient samples both at the time of discontinuation as well as during the subsequent months. Results: At the time of discontinuation, patients show a mature NK cell phenotype, probably associated to TKI treatment. However, 3 months after discontinuation, significant changes in several NK cell receptors occurred. Patients with a higher proportion of CD56dim NK and PD-1+ NK cells showed better chances of survival. More interestingly, non-relapsing patients also presented a subpopulation of NK cells with features associated with the expansion after cytomegalovirus infection (expression of CD57+NKG2C+), and higher proportion of NKp30 and NKp46 natural cytotoxicity receptors, which resulted in greater degranulation and associated with better survival (p<0.0001). Discussion: This NK cell subset could have a protective role in patients who do not relapse, thus further characterization could be useful for patients in sustained deep molecular response.

Elevated plasma levels of IL-6 and MCP-1 selectively identify CML patients who better sustain molecular remission after TKI withdrawal.

Treatment-free remission (TFR) in chronic myeloid leukemia (CML) is safe under adequate molecular monitoring, but questions remain regarding which factors may be considered predictive for TFR. Argentina Stop Trial (AST) is a multicenter TFR trial showing that 65% of patients sustain molecular remission, and the prior time in deep molecular response (DMR) was associated with successful TFR. Luminex technology was used to characterize cytokines in plasma samples. Using machine learning algorithms, MCP-1 and IL-6 were identified as novel biomarkers and MCP-1low/IL-6low patients showed eightfold higher risk of relapse. These findings support the feasibility of TFR for patients in DMR and MCP-1/IL-6 plasma levels are strong predictive biomarkers.

Real-world outcomes for the treatment of relapsed/refractory multiple myeloma patients with lenalidomide-dexamethasone combinations in a Latin American country. A retrospective cohort study from grupo argentino de mieloma múltiple.

OBJECTIVES: We compared the efficacy of lenalidomide-dexamethasone (Rd) based treatments for relapsed/refractory multiple myeloma patients (pts), in a real-world setting. In addition, we evaluated adverse events (AE), progression-free survival (PFS) and overall survival (OS). METHODS: In our retrospective, multicentric study, 156 pts with RRMM were included. 74/156 pts (47%) were refractory to bortezomib (V) and 43/156 (27%) pts to lenalidomide (R), with 24/156 (15%) of pts double refractory. Eighty-six pts (55%) received Rd with carfilzomib (KRd), 30 pts (19%) bortezomib (VRd), 30 pts (19%) daratumumab (DRd), and 10 pts (6%) ixazomib (IRd). RESULTS: The overall response (ORR) (≥ partial response) for the entire cohort was 71%, with a very good partial response rate or better (≥VGPR) of 35%. We found no significant differences in CR or ≥VGRP rates between treatments (p:0.229). Regardless of the combination received, those patients who achieved CR had significantly improved PFS (p: 0.007). The most frequent cause of treatment discontinuation was disease progression in 55/156 pts (35%). 8 pts (5%) discontinued treatment due to treatment-related adverse events (AE). CONCLUSION: This is the first report of Rd combinations for the treatment of RRMM in Latin America. All combinations proved to be effective with an acceptable toxicity.

Comparison of matched sibling, unrelated and haploidentical donors in hematopoietic stem cell transplantation. A real world experience from the Argentine Group For Bone Marrow Transplantation And Cell Therapy (GATMO-TC) / Comparación de donantes relacionados, no relacionados y haploidénticos en trasplante de progenitores hematopoyéticos. Experiencia del Grupo Argentino de Trasplante de Médula Ósea y Terapia Celular (GATMO-TC)

Abstract We retrospectively analyzed 570 adult patients who received allogeneic stem cell transplantation for malignant diseases. The outcomes were compared according to donor type. Most of the patients (60%) were transplanted for acute leukemia. Median follow-up was 1.6 years. Haploidentical allogeneic stem cell transplantation was more frequently performed for acute myeloid leukemia and in late stages than any other donor type. Non-relapse mortality at 100 days and one year for unrelated and haploidentical donors were similar, 19%-29% vs. 17%-28%, respectively. A significant better non-relapse mortality was observed for matched sibling donors (7%-15%; p < 0.001). Relapse rate was higher in haploidentical donors compared to matched sibling and unrelated donors (three year relapse rate 46%, 39%, 28%; respectively p < 0.001). Haploidentical donors resulted in lower three year progression-free survival and worse 3 year overall survival (32%; p < 0.001 and 42%; p < 0.001) compared with other donors (44% and 55% MSD, 40% and 42% UD, respectively). The incidence of grade II-IV acute graft-versus-host disease was higher in unrelated donors (51% unrelated, 35% haploidentical, 36% matched sibling; respectively; p = 0.001), with no difference in grades III-IV (p = 0.73) or in chronic graft-versus-host disease (p = 0.2) between groups. After multivariate analysis, haploidentical and unrelated donors remained negatively associated with non-relapse mortality (HR 1.95; 95% CI 1.10-3.20 and HR 2.70; 95% CI 1.63-4.46, respectively). Haploidentical donors were associated with a higher risk of relapse and worse overall survival. This analysis shows that haploidentical donors were associated with similar non-relpase mortality and higher relapse rates than unrelated donors. Better results in non-relapse mortality were observed for matched sibling donors.

Resumen Se efectuó un análisis retrospectivo de 570 pacientes adultos que recibieron un trasplante alogénico de precursores hematopoyéticos, comparando los resultados según el tipo de donante. La mediana de seguimiento fue de 1.6 años. El 60% de la población se trasplantó por leucemias agudas. Los trasplantes haploidénticos se hicieron en su mayoría en leucemia mieloide aguda y en estadios tardíos en comparación a otros donantes. La mortalidad libre de enfermedad al día +100 y a 1 año fue similar para los donantes no emparentados y haploidénticos (19% y 29% vs. 17% y 28%, respectivamente). Se obtuvieron mejores resultados con donantes relacionados idénticos (7% y 15%; p < 0.001). La recaída fue mayor en los donantes haploidénticos (tres años 46% haploidénticos, 39% relacionados idénticos, 28% no emparentados; p < 0.003). El trasplante con donante haploidéntico presentó una menor supervivencia libre de progresión y menor supervivencia global a tres años (32%; p < 0.001 y 42%; p < 0.001). La incidencia de enfermedad injerto contra huésped aguda fue mayor en no emparentados (51%, 35% haploidénticos, 36% relacionados idénticos; p = 0.001), sin diferencias en grados III-IV (p = 0.73) o en EICH crónica (p = 0.2). Los trasplantes con donante haploidéntico y no emparentado mantuvieron su asociación negativa con mortalidad libre de enfermedad (HR 1.95; 95%IC 1.10-3.20 y HR 2.70; 95%IC 1.63-4.46), en análisis multivariado. El trasplante haploidéntico se asoció a mayor recaída y a menor supervivencia global. Esta experiencia mostró similar mortalidad libre de enfermedad entre trasplantes con donantes haploidénticos y no emparentados. Los trasplantes relacionados idénticos mostraron menores tasas de mortalidad libre de enfermedad.

Comparison of matched sibling, unrelated and haploidentical donors in hematopoietic stem cell transplantation. A real-world experience from the Argentine Group for Bone Marrow Transplantation and Cell Therapy (GATMO-TC).

We retrospectively analyzed 570 adult patients who received allogeneic stem cell transplantation for malignant diseases. The outcomes were compared according to donor type. Most of the patients (60%) were transplanted for acute leukemia. Median follow-up was 1.6 years. Haploidentical allogeneic stem cell transplantation was more frequently performed for acute myeloid leukemia and in late stages than any other donor type. Non-relapse mortality at 100 days and one year for unrelated and haploidentical donors were similar, 19%-29% vs. 17%-28%, respectively. A significant better non-relapse mortality was observed for matched sibling donors (7%-15%; p < 0.001). Relapse rate was higher in haploidentical donors compared to matched sibling and unrelated donors (three year relapse rate 46%, 39%, 28%; respectively p < 0.001). Haploidentical donors resulted in lower three year progression-free survival and worse 3 year overall survival (32%; p < 0.001 and 42%; p < 0.001) compared with other donors (44% and 55% MSD, 40% and 42% UD, respectively). The incidence of grade II-IV acute graft-versus-host disease was higher in unrelated donors (51% unrelated, 35% haploidentical, 36% matched sibling; respectively; p = 0.001), with no difference in grades III-IV (p = 0.73) or in chronic graft-versus-host disease (p = 0.2) between groups. After multivariate analysis, haploidentical and unrelated donors remained negatively associated with non-relapse mortality (HR 1.95; 95% CI 1.10-3.20 and HR 2.70; 95% CI 1.63-4.46, respectively). Haploidentical donors were associated with a higher risk of relapse and worse overall survival. This analysis shows that haploidentical donors were associated with similar non-relpase mortality and higher relapse rates than unrelated donors. Better results in non-relapse mortality were observed for matched sibling donors.

Se efectuó un análisis retrospectivo de 570 pacientes adultos que recibieron un trasplante alogénico de precursores hematopoyéticos, comparando los resultados según el tipo de donante. La mediana de seguimiento fue de 1.6 años. El 60% de la población se trasplantó por leucemias agudas. Los trasplantes haploidénticos se hicieron en su mayoría en leucemia mieloide aguda y en estadios tardíos en comparación a otros donantes. La mortalidad libre de enfermedad al día +100 y a 1 año fue similar para los donantes no emparentados y haploidénticos (19% y 29% vs. 17% y 28%, respectivamente). Se obtuvieron mejores resultados con donantes relacionados idénticos (7% y 15%; p < 0.001). La recaída fue mayor en los donantes haploidénticos (tres años 46% haploidénticos, 39% relacionados idénticos, 28% no emparentados; p < 0.003). El trasplante con donante haploidéntico presentó una menor supervivencia libre de progresión y menor supervivencia global a tres años (32%; p < 0.001 y 42%; p < 0.001). La incidencia de enfermedad injerto contra huésped aguda fue mayor en no emparentados (51%, 35% haploidénticos, 36% relacionados idénticos; p = 0.001), sin diferencias en grados III-IV (p = 0.73) o en EICH crónica (p = 0.2). Los trasplantes con donante haploidéntico y no emparentado mantuvieron su asociación negativa con mortalidad libre de enfermedad (HR 1.95; 95%IC 1.10-3.20 y HR 2.70; 95%IC 1.63-4.46), en análisis multivariado. El trasplante haploidéntico se asoció a mayor recaída y a menor supervivencia global. Esta experiencia mostró similar mortalidad libre de enfermedad entre trasplantes con donantes haploidénticos y no emparentados. Los trasplantes relacionados idénticos mostraron menores tasas de mortalidad libre de enfermedad.

Allogeneic stem cell transplantation improves survival in relapsed Hodgkin lymphoma patients achieving complete remission after salvage treatment.

Allogeneic stem cell transplant (alloSCT) is a current treatment option for patients with refractory/relapsed classic Hodgkin lymphoma (CHL), including those who have failed an autologous transplantation. We performed a retrospective multicenter analysis of 113 patients (median age 28 years; range 14-56; 54% males) with refractory/relapsed (R/R) CHL who had undergone alloSCT in Argentina. Kaplan-Meier was used to estimate overall (OS) and progression-free survival (PFS). Relapse rate (RR) and non-relapse mortality (NRM) were estimated with cumulative incidence analysis. Disease status at transplant was complete remission (CR) in 39%, partial remission (PR) in 44%, and stable/progressed disease (S/PD) in 17% of the patients. Donor type was matched related (MRD) in 60%, unrelated (URD) in 19%, and haploidentical (HID) in 21% of the patients. OS and PFS at 2 years were 43% and 27%, respectively, for all the cohort. In the univariate analysis, patients in CR showed better OS (p ≤ 0.001) and PFS (p ≤ 0.001), and lower NRM (p = 0.04). HID had better PFS (p = 0.04) and lower RR (p = 0.02). In the multivariate analysis, CR showed a significant impact on OS and PFS, and HID on PFS. AlloSCT is a feasible procedure in patients with CHL. Those in CR at the time of the transplant had better outcomes. Haploidentical transplantation is associated with better PFS in these patients with poor prognosis.

Evaluation of the primitive fraction by functional in vitro assays at the RNA and DNA level represents a novel tool for complementing molecular monitoring in chronic myeloid leukemia.

Quantification of BCR-ABL1 mRNA levels in peripheral blood of chronic myeloid leukemia patients is a strong indicator of response to tyrosine-kinase inhibitors (TKI) treatment. However, additional prognostic markers are needed in order to better classify patients. The hypothesis of leukemic stem cells (LSCs) heterogeneity and persistence, suggests that their functional evaluation could be of clinical interest. In this work, we assessed the primitive and progenitor fractions in patients at diagnosis and during TKI treatment using functional in vitro assays, defining a "functional leukemic burden" (FLB). We observed that the FLB was reduced in vivo in both fractions upon treatment. However, different FLB levels were observed among patients according to their response to treatment, suggesting that quantification of the FLB could complement early molecular monitoring. Given that FLB assessment is limited by BCR-ABL1 mRNA expression levels, we developed a novel detection method of primitive cells at the DNA level, using patient-specific primers and direct nested PCR in colonies obtained from functional in vitro assays. We believe that this method could be useful in the context of discontinuation trials, given that it is unknown whether the persistent leukemic clone represents LSCs, able to resume the leukemia upon TKI removal.

Hematopoietic Cell Transplantation-Specific Comorbidity Index Predicts Morbidity and Mortality in Autologous Stem Cell Transplantation.

The hematopoietic cell transplantation-specific comorbidity index (HCT-CI) score is a useful tool to assess the risk for nonrelapse mortality (NRM) after allogeneic hematopoietic stem cell transplantation. Although the HCT-CI has been investigated in autologous stem cell transplantation (ASCT), its use is limited. To improve on the current use of the HCT-CI score on the morbidity and mortality after ASCT, we assessed the 100-day morbidity defined as orotracheal intubation (OTI), dialysis or shock (vasopressors need), 100-day NRM, early composite morbidity-mortality (combined endpoint that included any previous endpoints), and long-term NRM. We retrospectively reviewed a cohort of 1730 records of adult patients who received an ASCT in Argentinean center's between October 2002 and August 2016. Median follow-up was 1.15 years, and median age was 53 years. Diseases were multiple myeloma (48%), non-Hodgkin lymphoma (27%), and Hodgkin lymphoma (17%); 51% were in complete or partial remission; and 13% received ≥ 3 chemotherapy lines before transplant (heavily pretreated). Early NRM (100-day) was 2.7%, 5.4% required OTI, 4.5% required vasopressors, and 2.1% dialysis, with an early composite morbidity-mortality of 6.8%. Long-term (1 and 3 years) NRM was 4% and 5.2% and overall survival 89% and 77%, respectively. High-risk HCT-CI patients had a significant increase in 100-day NRM compared with intermediate and low risk (6.1% versus 3.4% versus 1.8%, respectively; P = .002), OTI (11% versus 6% versus 4%, P = .001), shock (8.7% versus 5.8% versus 3%, P = .001), early composite morbidity-mortality (13% versus 9 % versus 4.7%, P < .001), and long-term NRM (1 year, 7.7% versus 4% versus 3.3%; and 3 years, 10.8% versus 4% versus 4.8%, respectively; P = .002). After multivariate analysis these outcomes remained significant: early composite morbidity-mortality (odds ratio [95% confidence interval] compared with low risk: intermediate risk 2.1 [1.3 to 3.5] and high risk 3.3 [1.9 to 5.9]) and NRM (hazard ratio [95% confidence interval] compared with low risk: intermediate risk .97 [.8 to 2.4] and high risk 3.05 [1.3 to 4.5]). No significant impact was observed in overall survival. Other than comorbidities, significant impact was observed for heavily pretreated patients, age ≥ 55 years, non-Hodgkin lymphoma, and bendamustine-etoposide-citarabine-melphalan conditioning. We confirmed that the HCT-CI had a significant impact on NRM after ASCT, and these findings are mainly due to early toxicity express as 100-day NRM and the 3 main morbidity outcomes as well as the composite endpoint.