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Introduction
Imatinib has indeed revolutionized the treatment of chronic myelogenous leukemia (CML) since more than 15 years now, especially in CP. The first patients (pts) in this setting were ...treated with this compound within the IRIS phase III trial from Novartis, started in January 2000. Regular updates of the results of this study have been presented during various meetings until year 7, and academic studies have recently reported the outcomes of IM first-line CP CML pts after 66 months follow-up. However, little is known about the very long-term outcomes (>8 years) of such first-line pts and these data might be of interest while generic forms of IM will be soon launched in this setting.
In this study, we aimed to look at long-term outcomes in terms of efficacy and toxicities in first-line CP CML pts treated with branded form of IM (Glivec®).
Methods
This is a comprehensive retrospective analysis of first-line CP CML pts treated with IM first-line 400 mg daily since diagnosis and followed in 2 university reference centers for CML between 2000 and 2015, inside or outside academic or industrial clinical trials. All living pts have given their agreement for participation in this retrospective analysis. Pts have been analyzed in intention-to-treat, CML was defined according to ELN criteria CP, accelerated phase (AP) and blast crises (BC), Sokal, Euro and EUTOS scores have been calculated as published. Molecular biology tests have been performed according to ELN guidelines and BCR-ABL1/ABL1 were expressed as % on the international scale and 3 ELN conversion factors have been applied successively along time according to material exchanges performed with the central European laboratory in Mannheim. Cytogenetic and molecular responses have been defined according to the ELN criteria. Overall survival (OS) was calculated from the date of IM initiation until death at any time and for any reason; until progression to AP or BC at any time for progression-free survival (PFS); and until death, progression to AP or BC, failure on IM or IM treatment discontinuation for any cause including treatment-free remission (TFR), for event-free survival (EFS). The cut-off date for this analysis was the 20th of July 2,015.
Results
At time of analysis, 120 pts could be analyzed, with a median follow-up of 85.5 (1-194) months, 70 (58%) were males, with a median age of 55 (11-85) at IM initiation. Sokal score was high for 24(20%) pts, intermediate for 58 (49%), low for 34 (30.5%), unknown in 4 (0.5%) pts. Four (3.5%) pts had a variant Ph chromosome, 7 (6%) with additional chromosomal abnormalities, and 2 a masked Ph chromosome, 6 harbored atypical BCR-ABL1 transcripts excluded from analysis. Early molecular response (M3) was achieved in 86 (72%) pts, unreached in 20 (16%) pts, and unknown for 15 (12.5%) pts. It was predictive of Major Molecular Response (MMR) at 12 months (p=0.01, OR 5.35, 95%CI 1.3-31.94), for MR4 rates at 24 months (p=0.03, OR 7.35 95%CI 1-328) and for EFS (p=0.006) but not for OS and PFS in a multivariate Cox model analysis. MMR was achieved in 42% of evaluable pts at 12 months. Eutos, Euro and Sokal scores had no impact on OS, PFS and EFS. Five pts progressed to BC (1 myeloid, 4 lymphoid) within the 5 first years and died after allogeneic stem cell transplantation. The PFS rates were 97.5% at 2 years, 92% at 5 years, 88.6% at 10 and 14 years, EFS rates were 76% at 2 years, 60% at 5 years, 45% at 10 years and 21% at 14 years (figure 1), OS rates were 98% at 2 years, 95% at 5 years, 87% at 10 and 14 years.
Figure 1: PFS and EFS in pts on IM first-line. (Dashed lines represent 95%CI).
MR4.5 was achieved in 58 (48.5%) pts after a median of 46 (3-191) months and TFR strategy (or trial) was proposed in 28 pts (23.5%) and successful in 15 (12.5%) pts. At latest follow-up, after a median of 85.5 (4-180) months, 64 (53.5%) pts are still on IM, and 44 (37%) have switched to an alternative therapy for intolerance (17 pts, 14%) or resistance (16 pts, 13.5%, 7 with a BCR-ABL mutation) to IM and 11 for other causes (pregnancy, secondary tumors…). Overall, at latest follow-up, 10/120 pts died, 5 of CML progression and 5 from other causes.
Conclusions
After a very long median follow-up of more than 85 months, IM still consistently provides high rates of remission and survival, without disease progression and severe long-term toxicities. In addition, half of the pts reached the MR4.5 level, ≥2 years stable in 23.5% of the pts offering the possibility of a treatment-free strategy.
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Nicolini:Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Ariad Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Mahon:Novartis: Consultancy, Honoraria; ARIAD: Consultancy; Pfizer: Consultancy; Bristol-Myers Squibb: Consultancy, Honoraria. Etienne:Novartis: Consultancy, Honoraria; BMS: Honoraria.
Highlights • The prognosis of many patients with AML, especially CN-AML, remains uncertain. • The optimal post-remission therapy for such patients is unclear. • TET2 exon 2 skipping (TET2E2S) has ...been identified in AML cells. • We hypothesize that TET2E2S may serve as biomarker for outcomes in AML. • TET2E2S was found associated with a reduced relapse rate and prolonged survival. • Assessment of TET2 exon 2 splicing status might improve AML risk stratification
The nucleoside analogue cytarabine (AraC) has served as the backbone of acute myeloid leukemia (AML) treatment for nearly forty years. About one-third of expressed genes are abnormally spliced in AML ...yet alternative exon usage (AEU) plays a role in the plasticity of tumor cells and may influence the response to treatment. Here the exon expression profiles of the erythroleukemia K562 cell line were compared to that of its AraC-resistant variant K562/AraC through Affymetrix HTA2 exon arrays. 5140 exon events harbored by 2583 genes distinguished the 2 cell lines. Among these, the skipping of TET2 exon 2 was identified in K562 cells sensitive to AraC whereas TET2 gene expression remained unchanged at the whole transcript level. The results were confirmed by exon-specific RTPCR (ESPCR). Microarray analysis did not evidenced any significant change in mRNA splicing for the 10 remaining exons of the TET2 gene.
TET2 is a dioxygenase that catalyzes the conversion of 5-methylcytosine (5-mC) to 5-hydroxymethylcytosine (5-hmC) and promote DNA demethylation. TET2 somatic mutations occur in about 25% AML, distributing across the whole coding sequence without obvious hot spots. These mutations decrease TET2 enzymatic activity by truncating the protein or affecting its catalytic activity. TET2 exon 2 is spliced in a mutually exclusive manner with exon 1 yet it is used as an alternative promoter (https://fasterdb.lyon.unicancer.fr/). However, TET2 exon 2 is not translated into protein and its role in TET2 regulation is still unknown. Having found that AraC sensitive cells harbor the spliced TET2 isoform, we investigated whether or not skipping of TET2 exon 2 correlate with disease outcome in AML patients treated with AraC-based intensive chemotherapy (AraC-IC).
The discovery cohort included 106 consecutive AML patients treated with AraC-IC (median age 57.91, 64 males). RNA was extracted from bone marrow MNCs and assayed for TET2 exon 2 skipping through real-time quantitative ESRTPCR (qESRTPCR) amplification of E1E3 (spliced) and E2E3 (unspliced) TET2 isoforms. TET2 exon 2 skipping was quantified by calculating the ratio E1E3/E2E3. For statistical analysis, the ratio E1E3/E2E3 was dichotomized using median value as the cutoff value. Skipping of TET2 exon 2 was associated with a significantly lower response rate: 65% vs 92%, p = 0.001 but with a significantly lower relapse rate: 39% vs 85%: p<10-4. Univariate analysis (27 months median follow-up) showed that in addition to age and cytogenetic risk, TET2 exon 2 skipping significantly influenced DFS; the higher the level of E1E3 isoform expression, the better the outcome HR=0.27 (95% confidence interval (CI):0.13-0.53), p<10-4. The favorable effect of TET2 exon 2 skipping on DFS remained in the 49 patients with normal karyotype: HR=0.31 (CI: 0.12-0.84), p=0.022. Multivariate analysis showed that age HR=1.83 (CI:1.03-3.24), p=0.039, cytogenetics HR=3.03 (CI:1.55-5.96), p=0.001, and TET2 exon 2 skipping HR=0.38 (CI:0.19-0.77), p=0.007 were independent prognostic factors for DFS. The validation cohort included 103 patients with normal karyotype treated with AraC-IC (median age 61.12, 63 males). Skipping of TET2 exon 2 was associated with a lower response rate: 87.5% vs 91.1% (NS) and a significantly lower relapse rate: 3% vs 66%: p<10-4. Univariate analysis showed that in addition to age, FLT3 internal tandem duplication (FLT3-ITD), nucleophosmin (NPM1) exon-12 gene mutation, TET2 exon 2 skipping significantly influenced DFS, EFS, and OS. In multivariate analysis, TET2 exon 2 skipping was the sole prognostic factor for DFS HR=0.07 (CI: 0.02-0.3), p<10-4, EFS HR=0.32 (CI: 0.14-0.74), p=0.008, and OS HR=0.42 (CI: 0.19-0.90), p=0.025. As an additional control, the prognostic effect of TET2 exon 2 skipping was evaluated in a series of 36 AML unfit for IC and treated with hydroxyurea, azacitidine, decitabine, low dose AraC, or supportive care only. TET2 exon 2 skipping possessed no significant impact on the response rate, the relapse rate, OS, DFS, and EFS in this population.
In conclusion TET2 exon 2 skipping is associated with a low relapse rate and possesses a strong favorable prognostic impact in AML treated with AraC-CTI. The mechanism linking this alternative exon usage with resistances to AraC are currently investigated while our results suggest that the determination of TET2 exon 2 splicing status might assist risk stratification.
Nicolini:Novartis: Consultancy.
•Adult allogeneic hematopoietic stem cell transplantation recipients should be reimmunized following a primary vaccination schedule.•The pediatric diphtheria, tetanus, acellular pertussis, hepatitis ...B virus, inactivated polio virus, and Haemophilus influenzae type b vaccine induces high (>90%) and sustained response rates.•Side effects of vaccination are rare and mild.•Hematologic and transplant-related characteristics affect antibody levels.
Data on immunogenicity and safety of the recommended revaccination schedule against diphtheria, tetanus, poliomyelitis, pertussis, Haemophilus influenzae type b (Hib), and hepatitis B in adult allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients are limited. This prospective single-center cohort study (April 2014 to March 2018) included adult allo-HSCT recipients referred to a dedicated vaccinology consultation and vaccinated with the pediatric combined diphtheria, tetanus, acellular pertussis, hepatitis B virus, inactivated poliovirus, and Haemophilus influenzae type b (DTaP(±HB)-IPV-Hib) vaccine (3 doses 1 month apart, booster dose 1 year later). The proportion of responders to tetanus, diphtheria, Hib, and hepatitis B vaccine and geometric mean concentrations (GMCs) of antibodies were assessed before and up to 24 months after vaccination. A total of 106 patients were vaccinated at a median (interquartile range) time of 12.4 (10 to 18.4) months post-transplant. At 5.3 (4.8 to 6.6) and 23.1 (21.1 to 25.1) months after vaccine initiation, high and sustained rates of protective antibody titers were achieved for tetanus (97.8% 95% confidence interval (95% CI), 92.4% to 99.7%, n = 91/93 and 100% 95% CI, 92% to 100%, n = 44/44), diphtheria (94.6% 95% CI, 87.9% to 98.2%, n = 88/93 and 90.9% 95% CI, 78.3% to 97.5%, n = 40/44), Hib (96.6% 95% CI, 90.4% to 99.3%, n = 85/88 and 93% 95% CI, 80.9% to 98.5%, n = 40/43), and hepatitis B (83.5% 95% CI, 73.5% to 90.9%, n = 66/79 and 81.1% 95% CI, 64.8% to 92%, n = 30/37). Underlying disease, stem cell source, chronic graft-versus-host-disease, and extracorporeal photopheresis differentially influenced GMCs of tetanus, diphtheria, and hepatitis B antibodies after 3 doses but not in the long term (24 months). Six (5.7%) patients experienced mild side effects. The pediatric DTaP(±HB)-IPV-Hib vaccine was safe and effective in eliciting a sustained protective humoral response in adult allo-HSCT recipients. Hepatitis B revaccination might be optimized by using higher antigen doses.
Hairy cell leukemia is a rare chronic lymphoproliferative disorder. Its diagnosis remains difficult due to different variant forms and differential diagnosis that are splenic marginal zone lymphoma ...and b-prolymphocytic leukemia. The prognosis of this malignancy has been transformed by purine nucleoside analogs, interferon, monoclonal antibodies and recombinant immunotoxins usually used in refractory or relapsed disease. The discovery of BRAF V600E mutation has become the milestone in the disease's history since it was uniformly identified in a HCL series in 2011. This mutation, commonly identified in melanoma, involves the protooncogene BRAF, a MAP3Kinase belonging to the RAF-MEK-ERK signaling pathway, which is the central key in several oncogenic processes. This mutation suggests disease-specific oncogene dependence. The detection of this mutation provides an additional diagnosis marker (because not found in variant forms), a best for monitoring minimal residual disease and a therapeutic target with the BRAF inhibitors in specific subgroups of patients, already tested in melanoma. This review aims to summarize the clinical and biological aspects and treatment of hairy cell leukemia and discusses the perspectives provided by the discovery of BRAF mutation in this disease.
The development of new lymphatic vessels occurs in many cancerous and inflammatory diseases through the binding of VEGF-C to its receptors, VEGFR-2 and VEGFR-3. The regulation of VEGFR-2/VEGFR-3 ...heterodimerisation and its downstream signaling in lymphatic endothelial cells (LECs) remain poorly understood. Here, we identify the endocytic receptor, uPARAP, as a partner of VEGFR-2 and VEGFR-3 that regulates their heterodimerisation. Genetic ablation of uPARAP leads to hyperbranched lymphatic vasculatures in pathological conditions without affecting concomitant angiogenesis. In vitro, uPARAP controls LEC migration in response to VEGF-C but not VEGF-A or VEGF-CCys156Ser. uPARAP restricts VEGFR-2/VEGFR-3 heterodimerisation and subsequent VEGFR-2-mediated phosphorylation and inactivation of Crk-II adaptor. uPARAP promotes VEGFR-3 signaling through the Crk-II/JNK/paxillin/Rac1 pathway. Pharmacological Rac1 inhibition in uPARAP knockout mice restores the wild-type phenotype. In summary, our study identifies a molecular regulator of lymphangiogenesis, and uncovers novel molecular features of VEGFR-2/VEGFR-3 crosstalk and downstream signaling during VEGF-C-driven LEC sprouting in pathological conditions.
Outcomes of allogeneic hematopoietic cell transplantation (allo‐HCT) for adult acute lymphoblastic leukemia (ALL) have improved over time. Studies have shown that total body irradiation (TBI) is the ...preferable type of myeloablative conditioning (MAC). However, outcomes based on central nervous system (CNS) involvement, namely CNS‐positive versus CNS‐negative, have not been compared. Here, we evaluated outcomes of 547 patients (CNS‐positive = 96, CNS‐negative = 451) who were allografted in the first complete remission (CR1) between 2009 and 2019. Primary endpoint was leukemia‐free survival (LFS). Median follow‐up was not different between the CNS‐positive and CNS‐negative groups (79 versus 67.2 months, P = 0.58). The CNS‐positive group were younger (median age 31.3 versus 39.7 years, P = 0.004) and were allografted more recently (median year 2012 versus 2010, P = 0.003). In both groups, MAC was the preferred approach (82.3% versus 85.6%, P = 0.41). On multivariate analysis, the CNS‐positive group had higher incidence of relapse (RI) (hazard ratio HR = 1.58 95% confidence interval (CI) = 1.06‐2.35, P = 0.025), but no adverse effect on LFS (HR = 1.38 95% CI = 0.99‐1.92, P = 0.057) or overall survival (OS) (HR = 1.28 95% CI = 0.89‐1.85, P = 0.18). A subgroup multivariate analysis limited to CNS‐positive patients showed that a TBI‐based MAC regimen resulted in better LFS (HR = 0.43 95% CI = 0.22‐0.83, P = 0.01) and OS (HR = 0.44 95% CI = 0.21‐0.92, P = 0.03) and lower RI (HR = 0.35 95% CI = 0.15‐0.79, P = 0.01). Another subgroup analysis in CNS‐negative patients showed that MAC‐TBI preparative regimens also showed a lower RI without a benefit in LFS or OS. While a MAC‐TBI allo‐HCT regimen may not be suitable to all, particularly for older patients with comorbidities, this approach should be considered for patients who are deemed fit and able to tolerate.