Incidence, treatment and outcome of central nervous system relapse in adult acute lymphoblastic leukaemia patients treated front-line with paediatric-inspired regimens: A retrospective multicentre Campus ALL study.

Within the Campus ALL network we analyzed the incidence, characteristics, treatment and outcome of a central nervous system (CNS) relapse in 1035 consecutive adult acute lymphoblastic leukemia (ALL) patients treated frontline with pediatric-inspired protocols between 2009 and 2020. Seventy-one patients (6.8%) experienced a CNS recurrence, more frequently in T- (28/278; 10%) than in B-ALL (43/757; 5.7%) (p = 0.017). An early CNS relapse-< 12 months from diagnosis-was observed in 41 patients. In multivariate analysis, risk factors for early CNS relapse included T-cell phenotype (p = <0.001), hyperleucocytosis >100 × 109 /L (p<0.001) and male gender (p = 0.015). Treatment was heterogeneous, including chemotherapy, radiotherapy, intrathecal therapy and novel agents. A complete remission (CR) was obtained in 39 patients (55%) with no differences among strategies. After CR, 26 patients underwent an allogenic transplant, with a significant overall survival benefit compared to non-transplanted patients (p = 0.012). After a median observation of 8 months from CNS relapse, 23 patients (32%) were alive. In multivariate analysis, the time to CNS relapse was the strongest predictor of a lower 2-year post-relapse survival (p<0.001). In conclusion, in adult ALL the outcome after a CNS relapse remains very poor. Effective CNS prophylaxis remains the best approach and allogenic transplant should be pursued when possible.

Multicenter retrospective analysis of clinical outcome of adult patients with mixed-phenotype acute leukemia treated with acute myeloid leukemia-like or acute lymphoblastic leukemia-like chemotherapy and impact of allogeneic stem cell transplantation: a Campus ALL study.

Mixed-phenotype acute leukemia (MPAL) is a rare disease. Treatment is often similar to that of acute lymphoblastic leukemia (ALL), but the outcome in adults and the role of allogeneic stem cell transplantation (AlloSCT) are not well defined. We report on 77 adult patients diagnosed with MPAL over the last 10 years and treated with a curative intent. Median age was 49 years; 7.6% of cases had a BCR::ABL1 rearrangement. Thirty patients (39%) were treated with an acute myeloid leukemia (AML)-like induction and 47 (61%) with an ALL-like scheme. The complete remission (CR) rate was 67.6% and an ALL-like therapy was associated with a better CR rate (P = 0.048). The median OS was 41.9 months; age ≤ 60 years was associated with a better OS (67 vs 26 months, P = 0.014). An AlloSCT was performed in 50 patients (65%). The 5-year OS of transplanted patients was 54%. The OS post-AlloSCT was better in patients who were minimal residual disease (MRD)-negative prior to transplant (75.8% vs 45.2%, P = 0.06). This study shows that MPAL patients respond better to an ALL-like induction therapy; that consolidation therapy should include, whenever possible, an AlloSCT and that MRD negativity should be a primary endpoint of treatment.

Apoptosis reprogramming triggered by splicing inhibitors sensitizes multiple myeloma cells to Venetoclax treatment.

Identification of novel vulnerabilities in the context of therapeutic resistance is emerging as a key challenge for cancer treatment. Recent studies have detected pervasive aberrant splicing in cancer cells, supporting its targeting for novel therapeutic strategies. Here, we evaluated the expression of several spliceosome machinery components in multiple myeloma (MM) cells and the impact of splicing modulation on tumor cell growth and viability. A comprehensive gene expression analysis confirmed the reported deregulation of spliceosome machinery components in MM cells, compared to normal plasma cells from healthy donors, with its pharmacological and genetic modulation resulting in impaired growth and survival of MM cell lines and patient-derived malignant plasma cells. Consistent with this, transcriptomic analysis revealed deregulation of BCL2 family members, including decrease of anti-apoptotic long form of myeloid cell leukemia-1 (MCL1) expression, as crucial for "priming" MM cells for Venetoclax activity in vitro and in vivo, irrespective of t(11;14) status. Overall, our data provide a rationale for supporting the clinical use of splicing modulators as a strategy to reprogram apoptotic dependencies and make all MM patients more vulnerable to BCL2 inhibitors.

Overall survival of myelodysplastic syndrome patients after azacitidine discontinuation and applicability of the North American MDS Consortium scoring system in clinical practice.

BACKGROUND: Azacitidine (AZA) is the standard treatment for myelodysplastic syndromes (MDS); however, many patients prematurely stop therapy and have a dismal outcome. METHODS: The authors analyzed outcomes after AZA treatment for 402 MDS patients consecutively enrolled in the Italian MDS Registry of the Fondazione Italiana Sindromi Mielodisplastiche, and they evaluated the North American MDS Consortium scoring system in a clinical practice setting. RESULTS: At treatment discontinuation, 20.3% of the patients were still responding to AZA, 35.4% of the cases had primary resistance, and 44.3% developed adaptive resistance. Overall survival (OS) was better for patients who discontinued treatment while in response because of planned allogeneic hematopoietic stem cell transplantation (HSCT; median OS, not reached) in comparison with patients with primary resistance (median OS, 4 months) or adaptive resistance (median OS, 5 months) or patients responsive but noncompliant/intolerant to AZA (median OS, 4 months; P = .004). After AZA discontinuation, 309 patients (77%) received best supportive care (BSC), 60 (15%) received active treatments, and 33 (8%) received HSCT. HSCT was associated with a significant survival advantage, regardless of the response to AZA. The North American MDS Consortium scoring system was evaluable in 278 of the 402 cases: patients at high risk had worse OS than patients at low risk (3 and 7 months, respectively; P < .001). The score was predictive of survival both in patients receiving BSC (median OS, 2 months for high-risk patients vs 5 months for low-risk patients) and in patients being actively treated (median OS, 8 months for high-risk patients vs 16 months for low-risk patients; P < .001), including transplant patients. CONCLUSIONS: Real-life data confirm that this prognostic scoring system for MDS patients failing a hypomethylating agent seems to be a useful tool for optimal prognostic stratification and for choosing a second-line treatment after AZA discontinuation.

Pre-transplant minimal residual disease assessment and transplant-related factors predict the outcome of acute myeloid leukemia patients undergoing allogeneic stem cell transplantation.

We studied pretransplant minimal residual disease (MRD) in 224 patients (median age 44 years; range 17-65) with acute myeloid leukemia (AML) undergoing allogeneic stem cell transplant (HSCT) in complete remission. MRD was evaluated on marrow samples using multicolor flow cytometry and assessment of WT1 gene expression. Both methods showed a strong prognostic value and their combination allowed the identification of three groups of patients with different risk of relapse. In multivariate analysis, combined MRD was the only predictor of cumulative incidence of relapse, regardless of donor type, conditioning regimen, first or second CR at HSCT, HSCT year, and ELN risk group. Multivariate regression model showed that only negative combined MRD status (P < .001) and myeloablative conditioning (P = .004) were independently associated with better OS. Among MRD-positive patients, a reduced incidence of relapse was observed in patients receiving haplo transplant (P < .05) and in patients who showed grade II-IV aGVHD (P < .03). In patients with negative combined MRD, the intensity of conditioning regimen did not affect the overall favorable outcome. We suggest that pretransplant MRD evaluation combined with transplant-related factors can identify AML patients at higher risk for relapse and might help in defining the overall transplant strategy.

Full donor chimerism after allogeneic hematopoietic stem cells transplant for myelofibrosis: The role of the conditioning regimen.

The aim of this retrospective study was to assess the rate of full donor chimerism (F-DC) in patients with myelofibrosis, prepared for an allogeneic stem cell transplant, with one or two alkylating agents. We analyzed 120 patients with myelofibrosis, for whom chimerism data were available on day +30. There were two groups: 42 patients were conditioned with one alkylating agent (ONE-ALK), either thiotepa or busulfan or melphalan, in combination with fludarabine, whereas 78 patients were prepared with two alkylating agents, thiotepa busulfan and fludarabine (TBF). Patients receiving TBF were older (57 vs 52 years), were less frequently splenectomized pre-HSCT (31% vs 59%), had more frequently intermediate-2/high DIPSS scores (90% vs 74%), were grafted more frequently from alternative donors (83% vs 33%) and received more frequently ruxolitinib pre-HSCT (26% vs 7%). The proportion of patients with F-DC on day +30, in the TBF vs the ONE-ALK group, was respectively 87% vs 45% (P < .001). The 5-year cumulative incidence of relapse was 9% in the TBF group, vs 43% for the ONE-ALK group (P < .001). The 5-year actuarial disease-free survival was 63% for TBF and 38% for the ONE-ALK group (P = .004). In conclusion, early full donor chimerism is a prerequisite for long term control of disease in patients with myelofibrosis, undergoing an allogeneic HSCT. The combination of two alkylating agents in the conditioning regimen, provides a higher chance of achieving full donor chimerism on day+30, and thus a higher chance of long term disease free survival.

The new small tyrosine kinase inhibitor ARQ531 targets acute myeloid leukemia cells by disrupting multiple tumor-addicted programs.

Tyrosine kinases have been implicated in promoting tumorigenesis of several human cancers. Exploiting these vulnerabilities has been shown to be an effective anti-tumor strategy as demonstrated for example by the Bruton's tyrosine kinase (BTK) inhibitor, ibrutinib, for treatment of various blood cancers. Here, we characterize a new multiple kinase inhibitor, ARQ531, and evaluate its mechanism of action in preclinical models of acute myeloid leukemia. Treatment with ARQ531, by producing global signaling pathway deregulation, resulted in impaired cell cycle progression and survival in a large panel of leukemia cell lines and patient-derived tumor cells, regardless of the specific genetic background and/or the presence of bone marrow stromal cells. RNA-seq analysis revealed that ARQ531 constrained tumor cell proliferation and survival through Bruton's tyrosine kinase and transcriptional program dysregulation, with proteasome-mediated MYB degradation and depletion of short-lived proteins that are crucial for tumor growth and survival, including ERK, MYC and MCL1. Finally, ARQ531 treatment was effective in a patient-derived leukemia mouse model with significant impairment of tumor progression and survival, at tolerated doses. These data justify the clinical development of ARQ531 as a promising targeted agent for the treatment of patients with acute myeloid leukemia.

Impact of HLA Disparity in Haploidentical Bone Marrow Transplantation Followed by High-Dose Cyclophosphamide.

We studied the impact of HLA mismatching on the outcome of 318 consecutive patients who received an unmanipulated haploidentical bone marrow transplant, followed by post-transplant cyclophosphamide (PTCy). The number of HLA-mismatched antigens was tested for its impact on overall survival (OS) and nonrelapse mortality (NRM), whereas HLA mismatches in the graft-versus-host (GVH) direction were tested for prediction of graft-versus-host disease (GVHD and relapse. Finally, we studied whether graft rejection correlated with the number of HLA mismatched antigens in host-versus-graft (HVG) direction. Two hundred thirty-one donor-recipient pairs (72%) had 4/8 mismatches at the -A, -B, -C, -DRB1 HLA loci. HLA mismatches did not predict the 2-year OS (hazard ratio, .83; P = .58) and NRM (subhazard ratio, 1.08; P = .93). The cumulative incidence of acute GVHD (P = .13), 1-year chronic GVHD (P = .84), and relapse rate (P = .26) did not correlate with univectorial GVH mismatches. Similarly, no correlation was observed between the amount of HLA mismatch in the HVG direction and graft rejection. In multivariate analysis advanced disease at transplant was the strongest predictor of survival, NRM, relapse, and graft rejection. In conclusion, the degree of HLA mismatching should not be used as a criterion to select family haploidentical donors when using bone marrow as stem cell source and PTCy for GVHD prophylaxis.

Depletion of SIRT6 enzymatic activity increases acute myeloid leukemia cells' vulnerability to DNA-damaging agents.

Genomic instability plays a pathological role in various malignancies, including acute myeloid leukemia (AML), and thus represents a potential therapeutic target. Recent studies demonstrate that SIRT6, a NAD+-dependent nuclear deacetylase, functions as genome-guardian by preserving DNA integrity in different tumor cells. Here, we demonstrate that also CD34+ blasts from AML patients show ongoing DNA damage and SIRT6 overexpression. Indeed, we identified a poor-prognostic subset of patients, with widespread instability, which relies on SIRT6 to compensate for DNA-replication stress. As a result, SIRT6 depletion compromises the ability of leukemia cells to repair DNA double-strand breaks that, in turn, increases their sensitivity to daunorubicin and Ara-C, both in vitro and in vivo In contrast, low SIRT6 levels observed in normal CD34+ hematopoietic progenitors explain their weaker sensitivity to genotoxic stress. Intriguingly, we have identified DNA-PKcs and CtIP deacetylation as crucial for SIRT6-mediated DNA repair. Together, our data suggest that inactivation of SIRT6 in leukemia cells leads to disruption of DNA-repair mechanisms, genomic instability and aggressive AML. This synthetic lethal approach, enhancing DNA damage while concomitantly blocking repair responses, provides the rationale for the clinical evaluation of SIRT6 modulators in the treatment of leukemia.

Performance of serum (1,3)-ß-d-glucan screening for the diagnosis of invasive aspergillosis in neutropenic patients with haematological malignancies.

We report our experience with the use of (1,3)-ß-d-glucan (BDG) screening for the diagnosis of invasive aspergillosis (IA) in neutropenic patients with haematological malignancies. The performance of BDG screening was assessed retrospectively in per patient and per sample analyses. Overall, 20 among 167 patients developed IA (12%). In the per patient analysis, BDG showed 60% sensitivity and 78% specificity when the criterion for positivity was the presence of at least one BDG value ≥80 pg/mL. For 2 consecutive positive results, sensitivity decreased to 40%, while specificity increased to 93% and was similar to that of a positive galactomannan (GM; 90%). The highest specificity (97%) was observed for combined positivity of at least one BDG and at least one GM. In the per sample analysis, the specificity of BDG was 100% in the best scenario, 96% in the median scenario and 89% in the worst scenario. BDG became positive before GM in 33% of IA patients with both markers positive (n = 12). Despite good specificity for 2 consecutive positive results, the BDG test offered unsatisfactory performance for the diagnosis of IA due to low sensitivity. The combination of BDG and GM showed the potential for increasing specificity.

Good tolerability of high dose colistin-based therapy in patients with haematological malignancies.

PURPOSE: Colistin is usually the only drug fully active against multi-drug resistant Gram-negative bacteria, but its nephrotoxicity might limit its use. Recent pharmacokinetic/pharmacodynamic data suggest that high dose of colistin, preceded by a loading dose, are needed to maximize its antibacterial effect. The aim of this study was to determine the safety of high doses colistin, in haematology population. METHODS: A retrospective review of haematology patients who received high dose colistin-based therapy in years 2011-2016 was performed. Nephrotoxicity was assessed using RIFLE criteria. RESULTS: Thirty patients who received 38 courses of colistin were included in the study. Colistin was always administered together with other antibiotics. Colistin was well tolerated, with one case of neurological toxicity and one of cutaneous reaction. There were 22 (58%) treatment cycles without any nephrotoxicity, even though during 16 of these cycles other nephrotoxic drugs were administered. Severe (injury or failure) renal toxicity occurred during 6 (16%) treatment courses, requiring colistin discontinuation in 2 patients and colistin dose reduction in 1. Poorer renal function at baseline and younger age were the only variables associated with increased renal toxicity (p = 0.011 and p = 0.031, respectively). Overall mortality was 18% (7/38) and 29% (11/38) at 7 and 30 days after the treatment onset. CONCLUSIONS: In adult haematology population, high dose colistin therapy is safe and efficacious, despite high frequency of concomitant nephrotoxic treatment.

High feasibility and antileukemic efficacy of fludarabine, cytarabine, and idarubicin (FLAI) induction followed by risk-oriented consolidation: A critical review of a 10-year, single-center experience in younger, non M3 AML patients.

About 105 consecutive acute myeloid leukemia (AML) patients treated with the same induction-consolidation program between 2004 and 2013 were retrospectively analyzed. Median age was 47 years. The first induction course included fludarabine (Flu) and high-dose cytarabine (Ara-C) plus idarubicin (Ida), with or without gemtuzumab-ozogamicin (GO) 3 mg/m(2) (FLAI-5). Patients achieving complete remission (CR) received a second course without fludarabine but with higher dose of idarubicin. Patients not achieving CR received an intensified second course. Patients not scheduled for early allogeneic bone marrow transplantation (HSCT) where planned to receive at least two courses of consolidation therapy with Ara-C. Our double induction strategy significantly differs from described fludarabine-containing regimens, as patients achieving CR receive a second course without fludarabine, to avoid excess toxicity, and Ara-C consolidation is administrated at the reduced cumulative dose of 8 g/m(2) per cycle. Toxicity is a major concern in fludarabine containing induction, including the recent Medical Research Council AML15 fludarabine, cytarabine, idaraubicin and G-CSF (FLAG-Ida) arm, and, despite higher anti-leukemic efficacy, only a minority of patients is able to complete the full planned program. In this article, we show that our therapeutic program is generally well tolerated, as most patients were able to receive subsequent therapy at full dose and in a timely manner, with a 30-day mortality of 4.8%. The omission of fludarabine in the second course did not reduce efficacy, as a CR rate of 83% was achieved and 3-year disease-free survival and overall survival (OS) were 49.6% and 50.9%, respectively. Our experience shows that FLAI-5/Ara-C + Ida double induction followed by risk-oriented consolidation therapy can result in good overall outcome with acceptable toxicity. Am. J. Hematol. 91:755-762, 2016. © 2016 Wiley Periodicals, Inc.

Safety and efficacy of (90) yttrium-ibritumomab-tiuxetan for untreated follicular lymphoma patients. An Italian cooperative study.

(90) Yttrium ((90) Y)-Ibritumomab-Tiuxetan combines the targeting advantage of a monoclonal antibody with the radiosensitivity of Follicular Lymphoma (FL). Previous studies showed that 90Y-IT is safe and effective in relapsed/refractory indolent FL, irrespective of prior treatment with rituximab. This multicentre trial aimed to evaluate the safety and the efficacy of "upfront" single-agent ((90) Y)-Ibritumomab-Tiuxetan in advanced-stage FL. The primary objective was the incidence of responses in terms of complete (CR) and partial remission (PR). Fifty patients with stage II "bulky", III or IV FL received a single treatment course with ((90) Y)-Ibritumomab-Tiuxetan as initial therapy. The median age was 60 years. Bone marrow involvement (<25%) was observed in 24 patients (48%) and 7 (14%) had an elevated lactate dehydrogenase level. The overall response (ORR) and CR rates were 94% and 86%, respectively with a median follow-up of 38·8 months. The median progression-free survival (PFS) was not reached, whereas the 3-year estimated PFS and overall survival (OS) rate was 63·4% and 90%, respectively. Grade 3/4 neutropenia and thrombocytopenia occurred in 30% and 26% of patients respectively; none experienced grade 3/4 non-haematological toxicity. No cases of secondary haematological malignancies were observed. ((90) Y)-Ibritumomab-Tiuxetan was demonstrated to be highly effective and safe as first-line treatment for advanced-stage FL.

Liposomal daunorubicin, fludarabine, and cytarabine (FLAD) as bridge therapy to stem cell transplant in relapsed and refractory acute leukemia.

Therapeutic options for patients with relapsed or refractory acute leukemia are still undefined and often unsatisfactory. We report the outcome of 79 patients with relapsed-refractory acute leukemia treated with fludarabine, cytarabine, and liposomal daunorubicin (FLAD regimen) followed by hematopoietic stem cell transplantation (HSCT), when clinically indicated, between May 2000 and January 2013. Forty-one patients had acute myeloid leukemia (AML), and 38 had acute lymphoblastic leukemia (ALL). Two patients with myeloid blast crises of CML and three with lymphoid blast crises were included in the AML and ALL subgroups, respectively. Median age was 48 years (range 13-77). FLAD was well tolerated with negligible, nonhematological toxicity. Six patients (7.5 %) died before response evaluation. Forty-seven patients achieved hematologic complete response (CR). Complete remission rate was 53 and 65 % among AML and ALL patients, respectively. No CR was recorded among 11 refractory AML patients. Twenty-four patients (30 %) underwent HSCT. Nine patients received stem cells from an HLA identical sibling, and 15 from an alternative donor (3 unrelated matched, 12 haploidentical sibling). Median overall survival in AML and ALL patients receiving FLAD therapy was 9 and 8 months, respectively. A 5-year projected OS for patients receiving the whole program (FLAD + HSCT) was 24 % for AML patients (median survival 43 months), 28 % for ALL patients treated in relapse (median survival 15 months), and 0 % for ALL patients treated for refractory disease. In this paper, we show that FLAD seems to be an effective bridge therapy to HSCT for a part of poor prognosis acute leukemia patients. However, prospective studies are needed to confirm our results.

De novo AML patients with favourable-intermediate karyotype may benefit from the addition of low-dose gemtuzumab ozogamicin (GO) to fludarabine, Ara-C and idarubicin (FLAI): a contribution to the reopened "GO question".

We report the final results of a prospective trial testing the combination of fludarabine, Ara-C and idarubicin (FLAI) followed by low-dose gemtuzumab ozogamicin (FLAI-GO) in 85 patients aged 60 years or more with CD33+ acute myeloid leukaemia (AML). Median age was 68 years (60-82); karyotype was unfavourable in 21 patients (24%), intermediate in 63 (74%) and favourable in 1 (2%). There were five therapy-related deaths. Of the 80 evaluable patients, 47 achieved complete response (CR) (58%); CR rates were 65 and 32% in good-intermediate/poor karyotype patients, respectively. Median length of CR was 7 months (3-76). The cumulative incidence of relapse was 84% with an actuarial survival of 50.3% at 1 year and 14.4% at 2 years. The study control population is an unselected consecutive historic cohort of 104 patients treated with the FLAI regimen, who were matched for age and prognostic factors. CR rates after FLAI-GO and FLAI were comparable. However, patients with de novo AML and intermediate-favourable karyotype receiving GO had a significantly lower risk of relapse at 2 years as compared to patients not receiving GO (n = 77) (40 vs 80%, p = 0.01) and significantly better disease-free survival (p = 0.018) and overall survival (p = 0.022).

Donor selection for adoptive immunotherapy with NK cells in AML patients: Comparison between analysis of lytic NK cell clones and phenotypical identification of alloreactive NK cell repertoire.

Natural killer (NK) cell-based adoptive immunotherapy in leukemia patients is an emerging field of interest based on clinical evidence of efficacy and safety. Elderly acute myeloid leukemia (AML) patients have been successfully treated with NK cells from HLA-haploidentical donors, especially when high amounts of alloreactive NK cells were infused. The aim of this study was comparing two approaches to define the size of alloreactive NK cells in haploidentical donors for AML patients recruited in two clinical trials with the acronym "NK-AML" (NCT03955848), and "MRD-NK". The standard methodology was based on the frequency of NK cell clones capable of lysing the related patient-derived cells. The alternative approach consisted of the phenotypic identification of freshly derived NK cells expressing, as inhibitory receptors, only the inhibitory KIR(s) specific for the mismatched KIR-Ligand(s) (HLA-C1, HLA-C2, HLA-Bw4). However, in KIR2DS2+ donors and HLA-C1+ patients, the unavailability of reagents staining only the inhibitory counterpart (KIR2DL2/L3) may lead to an underestimated identification of the alloreactive NK cell subset. Conversely, in the case of HLA-C1 mismatch, the alloreactive NK cell subset could be overestimated due to the ability of KIR2DL2/L3 to recognize with low-affinity also HLA-C2. Especially in this context, the additional exclusion of LIR1-expressing cells might be relevant to refine the size of the alloreactive NK cell subset. We could also associate degranulation assays, using as effector cells IL-2 activated donor peripheral blood mononuclear cells (PBMC) or NK cells upon co-culture with the related patient target cells. The donor alloreactive NK cell subset always displayed the highest functional activity, confirming its identification accuracy by flow cytometry. Despite the phenotypic limitations and considering the proposed corrective actions, a good correlation was shown by the comparison of the two investigated approaches. In addition, the characterization of receptor expression on a fraction of NK cell clones revealed expected but also few unexpected patterns. Thus, in most instances, the quantification of phenotypically defined alloreactive NK cells from PBMC can provide data similar to the analysis of lytic clones, with several advantages, such as a shorter time to achieve the results and, perhaps, higher reproducibility/feasibility in many laboratories.