Relevance of treatment-free remission recommendations in chronic phase chronic leukemia patients treated with frontline tyrosine kinase inhibitors.

BACKGROUND: Tyrosine kinase inhibitors (TKI) can be safely discontinued in chronic phase chronic myeloid leukemia (CP-CML) patients who had achieved a sustained deep molecular response. Based on the results of discontinuation trials, recommendations regarding patient selection for a treatment-free remission (TFR) attempt had been proposed. The aims of this study were to evaluate the rate of patients eligible for TKI discontinuation and molecular recurrence-free survival (MRFS) after stop according to recommendations. METHODS: Over a 10-year period, newly diagnosed CP-CML patients and treated with first-line TKI in the nine French participating centers were included. Eligibility to treatment discontinuation and MRFS were analyzed and compared according to selection criteria defined by recommendations and first-line treatments. RESULTS: From January 2006 to December 2015, 398 patients were considered. Among them, 73% and 27% of patients received imatinib or either second or third generation tyrosine kinase inhibitors as frontline treatment, respectively. Considering the selection criteria defined by recommendations, up to 55% of the patients were selected as optimal candidates for treatment discontinuation. Overall 95/398 (24%) discontinued treatment. MRFS was 51.8% [95% CI 41.41-62.19] at 2 years and 43.8% [31.45-56.15] at 5 years. Patients receiving frontline second-generation TKI and fulfilling the eligibility criteria suggested by recommendations had the lowest probability of molecular relapse after TKI stop when compare to others. CONCLUSION: One third of CP-CML patients treated with TKI frontline fulfilled the selection criteria suggested by European LeukemiaNet TFR recommendations. Meeting selection criteria and second-generation TKI frontline were associated with the highest MRFS.

Prospective Comparison of 18-FDG PET/CT and Whole-Body MRI with Diffusion-Weighted Imaging in the Evaluation of Treatment Response of Multiple Myeloma Patients Eligible for Autologous Stem Cell Transplant.

To compare the prognostic values of 18-FDG PET/CT (FDG-PET) and Whole-Body MRI with Diffusion-Weighted Imaging (WB-DW-MRI) in the evaluation of treatment response of Multiple Myeloma (MM) patients eligible for ASCT. Thirty patients with newly diagnosed MM prospectively underwent FDG-PET and WB-DW-MRI at baseline, after induction chemotherapy and after ASCT. Response on WB-DW-MRI was evaluated with the MY-RADS criteria. FDG-PET was considered positive if residual uptake was superior to liver uptake. Imaging results were not used for treatment modification. The impact of imaging results on PFS was analyzed. After a median follow-up of 32 months, 10 patients relapsed. With WB-DW-MRI, post-induction examination was positive in 3/25 and post-ASCT examination was positive in 3/27 patients. However, neither study showed prognostic impact on PFS. FDG-PET was positive in 5/22 post-induction and 3/26 patients post-ASCT, respectively. Positivity of FDG-PET, post-induction or post-ASCT, was associated with a shorter PFS (post-induction: median PFS 19 months vs. not reached, log-rank p = 0.0089; post-ASCT: median PFS 18 months vs. not reached, log-rank p = 0.0005). Preliminary results from this small, single-center, prospective study show that, whether performed post-induction or post-ASCT, FDG-PET has a higher prognostic value than WB-DW-MRI for treatment response evaluation of newly diagnosed MM.

Incidences of Deep Molecular Responses and Treatment-Free Remission in de Novo CP-CML Patients.

Background: Tyrosine Kinase Inhibitors (TKIs) discontinuation in patients who had achieved a deep molecular response (DMR) offer now the opportunity of prolonged treatment-free remission (TFR). Patients and Methods: Aims of this study were to evaluate the proportion of de novo chronic-phase chronic myeloid leukemia (CP-CML) patients who achieved a sustained DMR and to identify predictive factors of DMR and molecular recurrence-free survival (MRFS) after TKI discontinuation. Results: Over a period of 10 years, 398 CP-CML patients treated with first-line TKIs were included. Median age at diagnosis was 61 years, 291 (73%) and 107 (27%) patients were treated with frontline imatinib (IMA) or second- or third-generation TKIs (2-3G TKI), respectively. With a median follow-up of seven years (range, 0.6 to 13.8 years), 182 (46%) patients achieved a sustained DMR at least 24 months. Gender, BCR-ABL1 transcript type, and Sokal and ELTS risk scores were significantly associated with a higher probability of sustained DMR while TKI first-line (IMA vs. 2-3G TKI) was not. We estimate that 28% of CML-CP would have been an optimal candidate for TKI discontinuation according to recent recommendations. Finally, 95 (24%) patients have entered in a TFR program. MRFS rates at 12 and 48 months were 55.1% (95% CI, 44.3% to 65.9%) and 46.9% (95% CI, 34.9% to 58.9%), respectively. In multivariate analyses, first-line 2-3G TKIs compared to IMA and TKI duration were the most significant factors of MRFS. Conclusions: Our results suggest that frontline TKIs have a significant impact on TFR in patients who fulfill the selection criteria for TKI discontinuation.

Prospective comparison of 18-FDG PET/CT and whole-body diffusion-weighted MRI in the assessment of multiple myeloma.

Magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18FDG 18F-FDG PET-CT) are standard procedures for staging multiple myeloma (MM). Diffusion-weighted sequences applied to whole-body MRI (WB-DWI) improve its sensitivity. We compared the number of MM bone focal lesions (FLs) detected by 18F-FDG PET-CT and WB-DWI and evaluated the diagnostic performance of 18F-FDG PET-CT for diffuse infiltration. Thirty newly diagnosed MM patients prospectively underwent 18F-FDG PET-CT and WB-DWI. The criteria for skeletal region positivity were ≥ 1 focal bone lesions (FLs) and/or diffuse disease. MRI with the MY-RADS criteria was used as a reference standard for the diagnosis of diffuse infiltration. 18F-FDG PET-CT and WB-DWI were both interpreted as positive in 28/30 patients with an agreement of 1.00 (95% CI 0.77-1.00) between the two methods. The mean numbers of FLs were 16.7 detected by 18F-FDG PET-CT and 23.9 detected by WB-DWI (P = 0.028). WB-DWI detected more FLs in the skull (P = 0.001) and spine (P = 0.006). Agreement assessed using the prevalence and bias-corrected kappa index was moderate (0.40-0.60) for the spine, sternum-ribs and upper limbs and substantial (0.60-0.80) for the pelvis and lower limbs. As regards the diagnosis of diffuse bone marrow infiltration, the sensitivity, specificity and accuracy of 18F-FDG PET-CT were 0.75, 0.79 and 0.77, respectively. Although WB-DWI detected more FLs than did 18F-FDG PET-CT, there was no difference in the detection of bone disease on a per-patient basis. 18F-FDG PET-CT showed high performance, including for evaluation of diffuse infiltration.

Choline PET/CT in Multiple Myeloma.

The field of multiple myeloma (MM) imaging has evolved. The International Myeloma Working Group recently recommended performing 18F-fluorodeoxyglucose glucose (18FDG) positron emission tomography/computed tomography (PET/CT) with the aim of staging MM patients at baseline and evaluating response to therapy. Novel oncological radiotracers such as 11C-Choline and 18F-Fluorocholine, have been studied in comparison with 18FDG, mostly in MM patients presenting with refractory disease or suspected relapse. Choline-based tracers may overcome some limitations of 18FDG, which include a lack of sensitivity in depicting skull lesions and the fact that 10% of MM patients are FDG-negative. The majority of MM lesions display a higher uptake of Choline than FDG. Also, in many situations, Choline may offer better lesion visualization, with a higher tumor to background ratio; however, various patterns of Choline and FDG uptake have been observed in MM and some limitations, notably as regards liver lesions, should be recognized. Overall, Choline may provide additional detection of up to 75% more lesions. This article aims to provide a comprehensive review of the potential role of Choline in multiple myeloma, as compared to FDG, encompassing Choline physiopathology as well as data from clinical studies.

Nilotinib efficacy, safety, adherence and impact on quality of life in newly diagnosed patients with chronic myeloid leukaemia in chronic phase: a prospective observational study in daily clinical practice.

This observational, prospective study assessed, in a daily clinical practice, the molecular response, safety, quality of life (QoL) and treatment adherence in 183 patients with chronic myeloid leukaemia in chronic phase (CML-CP), receiving nilotinib as first-line treatment. Premature study termination before 24 months of follow-up occurred in 61 patients (33·3%), and was essentially due to nilotinib treatment discontinuation (n = 53; 29%), motivated by treatment intolerance (n = 29; 15·8%) and inefficacy (n = 19; 10·4%). After 24 months of treatment, 112/122 patients (91·8%) had a molecular assessment, 95·5% of whom achieved a major molecular response (MMR), 32·1% achieved uMR4 , defined as an undetectable molecular disease with 4-log molecular response sensitivity (≥10 000 ABL1 transcripts). The Morisky Green Levine Medication Adherence Scale was completed by 94/122 patients (77·0%), and 89·4% of these patients obtained a satisfactory level of treatment adherence, defined as a score ≥3. Patients' QoL was good at baseline and stable during the follow-up period. The two most common nilotinib-related adverse events (AEs) were pruritus (14·8%) and asthenia (13·7%). Seven patients (3·8%) experienced at least one cardiovascular ischaemic AE. This French nationwide cohort study provides relevant information in daily clinical practice indicating that nilotinib is a valuable first-line treatment option for CML-CP patients.

Incidence and outcome of BCR-ABL mutated chronic myeloid leukemia patients who failed to tyrosine kinase inhibitors.

PURPOSE: To assess the incidence of BCR-ABL kinase domain (KD) mutation detection and its prognostic significance in chronic phase chronic myeloid leukemia (CP-CML) patients treated with tyrosine kinase inhibitors (TKIs). PATIENTS AND METHODS: We analyzed characteristics and outcome of 253 CP-CML patients who had at least one mutation analysis performed using direct sequencing. Of them, 187 patients were early CP (ECP) and 66 were late CP late chronic phase (LCP) and 88% were treated with Imatinib as first-line TKI. RESULTS: Overall, 80 (32%) patients harbored BCR-ABL KD mutations. A BCR-ABL KD mutation was identified in 57% of patients, who progressed to accelerated or blastic phases (AP-BP), and 47%, 29%, 35%, 16% and 26% in patients in CP-CML at the time of mutation analysis who lost a complete hematologic response, failed to achieve or loss of a prior complete cytogenetic and major molecular response, respectively. Overall survival and cumulative incidence of CML-related death were significantly correlated with the disease phase whatever the absence or presence of a mutation was and for the latter the mutation subgroup (T315I vs P-loop vs non-T315I non-P-loop) (P<.001). Considering patients who were in CP at the time of mutation analysis, LCP mutated patients had a significantly worse outcome than ECP-mutated patients despite a lower incidence of T315I and P-loop mutations (P<.001). With a median follow-up from mutation analysis to last follow-up of 5 years, T315I and P-loop mutations were not associated with a worse outcome in ECP patients (P = .817). CONCLUSION: Our results suggest that early mutation detection together with accessibility to 2nd and 3rd generation TKIs have reversed the worst outcome associated with BCR-ABL KD mutations whatever the mutation subgroup in CP-CML patients.

Risk Factors for Steroid-Refractory Acute Graft-versus-Host Disease after Allogeneic Stem Cell Transplantation from Matched Related or Unrelated Donors.

We performed a retrospective study to identify pretransplantation risk factors for steroid-refractory (SR) acute graft-versus host disease (aGVHD) after allogeneic stem cell transplantation from matched donors in 630 adult patients who underwent transplantation at our center between 2000 and 2012. The cumulative incidence (CI) of SR aGVHD was 11.3% ± 2.3%. The identified independent risk factors were matched unrelated donor (hazard ratio [HR], 2.52; P = .001), female donor for male recipient (HR, 1.84; P = .023) and absence of antithymocyte globulin (HR, 2.02; P = .005). Three risk groups were defined according to the presence of these risk factors. In the whole cohort, the CI of SR aGVHD was 3.5% ± 1.7% in the low-risk group (0 risk factor, n = 115), 9.3% ± 1.6% in the intermediate-risk group (1 risk factor, n = 323), and 19.3% ± 2.9% in the high-risk group (2 or 3 risk factors, n = 192). Our study suggests that pretransplantation characteristics might help identify patients at high risk for SR aGVHD. A risk adapted first-line treatment of aGVHD could be evaluated in those patients.

ELN 2013 response status criteria: relevance for de novo imatinib chronic phase chronic myeloid leukemia patients?

The response definitions proposed by the European Leukemia Net (ELN) have been recently modified. We evaluated the new criteria for de novo imatinib (400 mg/d) chronic phase chronic myeloid leukemia (CP-CML) patients. Response status according to the 2009 and 2013 criteria were determined in 180 unselected patients. Outcome of the subgroups of patients were then compared. The 180 patients were classified as optimal responders (OR2009; n = 113, 62.7%), suboptimal responders (SOR2009; n = 47, 26.1%) and failures (FAIL2009; n = 20, 11.1%) according to the 2009 ELN criteria and optimal responders (OR2013; n = 77, 42.7%), warnings (WAR2013; n = 59, 32.7%), and failures (FAIL2013; n = 44, 24.4%) according to the 2013 ELN criteria. No difference in terms of outcome was observed between OR2009 patients who became WAR2013 when compared with OR2013 patients. When compared with FAIL2009 patients, SOR2009 patients who became WAR2013 had better EFS, FFS, PFS, and OS. No difference was observed in PFS or OS in SOR2009 patients who became FAIL2013. The 2013 ELN response status criteria have improved patients classification in terms of response status. However, in our patient population this improvement is related to a better definition of failure rather than that of optimal response for CP-CML patients treated with IM frontline therapy.

Identification of methylguanine methyltransferase polymorphisms as genetic markers of individual susceptibility to therapy-related myeloid neoplasms.

PURPOSE: Myelodysplastic syndromes (MDS) are pre-leukaemic haematopoietic stem cell disorders. Among them, 10-20% occur after chemotherapy and/or radiotherapy, and are called 'therapy-related MDS' (t-MDS). The aim of this study was to identify genetic markers in t-MDS. METHODS: A prospective cohort of 59 MDS patients (39 de novo MDS, 20 t-MDS) was studied. A total of 384 single nucleotide polymorphisms (SNP) selected among genes involved in DNA repair, drug metabolism and transport, signal transduction and oncogenesis, were genotyped using a custom-made SNP chip. RESULTS: Two non-synonymous SNPs present in the methylguanine methyltransferase (MGMT) gene, in complete linkage disequilibrium, were significantly associated with t-MDS: rs2308321 and rs2308327, with a raw p value of 7.4 × 10(-5) and a corrected p value after Benjamini-Hochberg correction of 0.014. Other associations tested between clinical and cytogenetic features and SNP chip gene variants gave corrected p values above 0.05. A validation cohort was separately constituted of 43 patients (24 de novo MDS, 19 t-MDS) and the two MGMT SNPs were genotyped; it confirmed a significant association between the variant allele of MGMT and t-MDS (p=0.038). CONCLUSION: We thus identified a putative marker of the risk to develop MDS after cancer treatment.

Potent graft-versus-leukemia effect after reduced-intensity allogeneic SCT for intermediate-risk AML with FLT3-ITD or wild-type NPM1 and CEBPA without FLT3-ITD.

To investigate the role of reduced-intensity allogeneic (RIC-allo) stem cell transplant (SCT) as postremission therapy in adult intermediate-risk patients with acute myelogenous leukemia (AML) with FLT3-ITD or wild-type NPM1 and CEBPA without FLT3-ITD, we conducted a single-center retrospective study between January 2001 and December 2010. Sixty-six patients were included: 37 treated with RIC-alloSCT and 29 with nonallogeneic SCT therapies. Both groups were comparable concerning age, WBC count at diagnosis, gender, karyotype, genotype, and number of courses of chemotherapy to reach complete remission (CR1). Median follow-up after CR1 was 37 months (range, 11-112 months) and 48 months (range, 9-83 months) in the allo and no-allo groups, respectively. In the allo versus no-allo groups, the 3-year cumulative incidence of relapse (CIR) rates were 25% ± 8% versus 61% ± 9%; P = .005. The 3-year nonrelapse mortality (NRM), overall survival (OS), and relapse-free survival (RFS) were 22% ± 7% versus 4% ± 4% (P = .005), 52% ± 9% versus 44% ± 10% (P = .75), and 53% ± 9% versus 35% ± 9% (P = .28), respectively. Multivariate analysis indicated that CIR was reduced by allo (hazard ratio [HR], 0.32; P = .01). A landmark analysis performed at day 185 after CR1 confirmed a lower CIR after allo. RIC-allo reduces the risk of relapse, suggesting a potent graft-versus-leukemia (GVL) effect in these patients at a high risk of relapse.

Missense SLC25A38 variations play an important role in autosomal recessive inherited sideroblastic anemia.

BACKGROUND: Congenital sideroblastic anemias are rare disorders with several genetic causes; they are characterized by erythroblast mitochondrial iron overload, differ greatly in severity and some occur within a syndrome. The most common cause of non-syndromic, microcytic sideroblastic anemia is a defect in the X-linked 5-aminolevulinate synthase 2 gene but this is not always present. Recently, variations in the gene for the mitochondrial carrier SLC25A38 were reported to cause a non-syndromic, severe type of autosomal-recessive sideroblastic anemia. Further evaluation of the importance of this gene was required to estimate the proportion of patients affected and to gain further insight into the range and types of variations involved. DESIGN AND METHODS: In three European diagnostic laboratories sequence analysis of SLC25A38 was performed on DNA from patients affected by congenital sideroblastic anemia of a non-syndromic nature not caused by variations in the 5-aminolevulinate synthase 2 gene. RESULTS: Eleven patients whose ancestral origins spread across several continents were homozygous or compound heterozygous for ten different SLC25A38 variations causing premature termination of translation (p.Arg117X, p.Tyr109LeufsX43), predicted splicing alteration (c.625G>C; p.Asp209His) or missense substitution (p.Gln56Lys, p.Arg134Cys, p.Ile147Asn, p.Arg187Gln, p.Pro190Arg, p.Gly228Val, p.Arg278Gly). Only three of these variations have been described previously (p.Arg117X, p.Tyr109LeufsX43 and p.Asp209His). All new variants reported here are missense and affect conserved amino acids. Structure modeling suggests that these variants may influence different aspects of transport as described for mutations in other mitochondrial carrier disorders. CONCLUSIONS: Mutations in the SLC25A38 gene cause severe, non-syndromic, microcytic/hypochromic sideroblastic anemia in many populations. Missense mutations are shown to be of importance as are mutations that affect protein production. Further investigation of these mutations should shed light on structure-function relationships in this protein.