No evidence that FLT3 status should be considered as an indicator for transplantation in acute myeloid leukemia (AML): an analysis of 1135 patients, excluding acute promyelocytic leukemia, from the UK MRC AML 10 and 12 trials

Fetal liver tyrosine kinase 3 (FLT3) internal tandem duplications (ITDs) are powerful adverse prognostic indicators for relapse in acute myelold leukemia (AML) but the most efficacious therapy for FLT3/ ITD+ patients is currently unknown. We evaluated outcome according to FLT3/ITD status in 1135 adult patients treated according to United Kingdom Medical Research Council (UK MRC) AML protocols: 141 received an autograft, and 170 received a matched sibling allograft in first complete remission (CR). An FLT3/ITD was detected in 25% of patients and was an independent predictor for relapse (P < .001). It remained prognostic for increased relapse in patients who received a transplant (odds ratio [OR] = 1.91; 95% confidence intervals [CIs] 1.13-3.21; P = .02), with no evidence of a difference in effect between patients who received an autograft (OR = 2.39; CIs = 1.24-4.62) and patients who received an allograft (OR = 1.31; CIs = 0.56-3.06) (test for interaction, P = .3) or between patients who did or did not receive a transplant (P = .4). These results were confirmed in an analysis of 186 patients randomized to receive or not receive an autograft in first CR and in a donor-versus-no donor analysis of 683 patients to assess the role of allograft (for latter, FLT3/ITD- OR = 0.70, CIs = 0.53-0.92; FLT3/ITD+ OR = 0.59, CIs = 0.40-0.87; test for interaction, P = .5). These results suggest that at present there is no strong evidence that FLT3 status should influence the decision to proceed to transplantation

Analysis of the clinical impact of NPM1 mutant allele burden in a large cohort of younger adult patients with acute myeloid leukaemia

Although an NPM1 mutation is generally considered to be a good prognostic marker in acute myeloid leukaemia, it has recently been suggested that a higher level of NPM1 mutant (NPM1MUT) alleles relative to wild‐type alleles is associated with poor clinical outcome. We therefore sought to confirm this finding in a larger study of 876 NPM1MUT cases entered into UK national trials. In univariate analysis, the higher NPM1MUT allele burden was associated with a lower complete remission (CR) rate, higher relapse rate and reduced overall survival, but this was largely attributable to the association of the higher NPM1MUT allele burden with other known poor risk factors, particularly the presence of a concomitant FLT3 internal tandem duplication. In multivariate analysis, there was no significant impact of the NPM1MUT allele burden on CR rates, and the impact on relapse and overall survival, whilst still significant, was greatly reduced. This impact was similar in patients who did or did not receive an allogeneic transplant in first CR. We conclude that the binary presence or absence of an NPM1 mutation, combined with minimal residual disease levels following induction therapy, should continue to be used in therapeutic management rather than stratification according to the NPM1MUT level

Therapy for isocitrate dehydrogenase 2 (IDH2)(R172)-mutant acute myeloid leukaemia

Although we earlier reported a very poor outcome for younger adult patients with isocitrate dehydrogenase 2 (IDH2)R172-mutated acute myeloid leukaemia (AML) entered into UK trials compared to IDH2WT and IDH2R140-mutated patients, this was not corroborated by a study from the German-Austrian AML Study Group. We have therefore investigated a later cohort of IDH2-mutated patients to identify any changes in outcome and whether this could inform the optimal treatment for IDH2R172 AML. We found an improved outcome for IDH2R172-mutated AML in the later trials and the data suggests that this may be due to the increased use of allogeneic transplantation to consolidate first remission

Impact of PTEN abnormalities on outcome in pediatric patients with T-cell acute lymphoblastic leukemia treated on the MRC UKALL2003 trial.

PTEN gene inactivation by mutation or deletion is common in pediatric T-cell acute lymphoblastic leukemia (T-ALL), but the impact on outcome is unclear, particularly in patients with NOTCH1/FBXW7 mutations. We screened samples from 145 patients treated on the MRC UKALL2003 trial for PTEN mutations using heteroduplex analysis and gene deletions using single nucleotide polymorphism arrays, and related genotype to response to therapy and long-term outcome. PTEN loss-of-function mutations/gene deletions were detected in 22% (PTEN(ABN)). Quantification of mutant level indicated that 67% of mutated cases harbored more than one mutant, with up to four mutants detected, consistent with the presence of multiple leukemic sub-clones. Overall, 41% of PTEN(ABN) cases were considered to have biallelic abnormalities (mutation and/or deletion) with complete loss of PTEN in a proportion of cells. In addition, 9% of cases had N- or K-RAS mutations. Neither PTEN nor RAS genotype significantly impacted on response to therapy or long-term outcome, irrespective of mutant level, and there was no evidence that they changed the highly favorable outcome of patients with double NOTCH1/FBXW7 mutations. These results indicate that, for pediatric patients treated according to current protocols, routine screening for PTEN or RAS abnormalities at diagnosis is not warranted to further refine risk stratification.Leukemia advance online publication, 21 August 2015; doi:10.1038/leu.2015.206

Additional impact of mutational genotype on prognostic determination in resistant and relapsed acute myeloid leukaemia

Outcome after failure of initial therapy in younger adult patients with acute myeloid leukaemia (AML) is highly variable. Cytogenetics, length of first remission (CR1) before relapse, and allogeneic transplantation are known prognostic factors, but the contribution of leukaemic genotype is less clear, particularly in resistant disease. Of 5,651 younger adult patients entered into UK MRC/NCRI AML trials between 1988 and 2014 with available FLT3ITD and NPM1 genotype, 326 (6%) had resistant disease and 2338 (41 %) relapsed after achieving CR1. Overall survival (OS) was significantly higher in relapsed compared to resistant disease (p = 0·03). Independent favourable prognostic factors for OS in resistant disease included lower blast cell percentage after two courses of induction therapy (p = 0.0006) and NPM1 mutant (NPM1MUT) (p = 0.04). In relapsed disease, longer CR1 was a favourable independent factor for attainment of CR2 (p < 0.0001) and OS from time of relapse (p < 0.0001), but CR2 rate and OS from relapse were significantly worse in those who had received an allograft in CR1 (respectively p < 0.05, p < 0·002). NPM1MUT was marginally beneficial for OS (p = 0.04). FLT3ITD and DNMT3AMUT were adverse factors for OS (respectively p < 0.0001, p = 0.02). Mutational analysis adds additional independent prognostic information to demographic features and previous therapy in patients with resistant and relapsed disease

Frailty: A global measure of the multisystem impact of COPD

Chronic obstructive pulmonary disease (COPD) is a multisystem disease that resembles the accumulation of multiple impairments seen in aging. A comprehensive geriatric assessment (CGA) captures multisystem deficits, from which a frailty index (FI) can be derived. We hypothesized that patients with COPD would be frailer than a comparator group free from respiratory disease. In this cross-sectional analysis, the CGA questionnaire was completed and used to derive an FI in 520 patients diagnosed with COPD and 150 comparators. All subjects were assessed for lung function, body composition, 6-minute walking distance (6MWD), and handgrip strength. Patients completed validated questionnaires on health-related quality of life and respiratory symptoms. Patients and comparators were similar in age, gender, and body mass index, but patients had a greater mean ± SD FI 0.16 ± 0.08 than comparators 0.05 ± 0.03. In patients, a stepwise linear regression 6MWD (β = −0.43), number of comorbidities (β = −0.38), handgrip (β = −0.11), and number of exacerbations (β = 0.11) were predictors of frailty (all p < 0.01). This large study suggests patients with COPD are frailer than comparators. The FI derived from the CGA captures the deterioration of multiple systems in COPD and provides an overview of impairments, which may identify individuals at increased risk of morbidity and mortality in COPD

Determinants of postnatal spleen tissue regeneration and organogenesis

Abstract The spleen is an organ that filters the blood and is responsible for generating blood-borne immune responses. It is also an organ with a remarkable capacity to regenerate. Techniques for splenic auto-transplantation have emerged to take advantage of this characteristic and rebuild spleen tissue in individuals undergoing splenectomy. While this procedure has been performed for decades, the underlying mechanisms controlling spleen regeneration have remained elusive. Insights into secondary lymphoid organogenesis and the roles of stromal organiser cells and lymphotoxin signalling in lymph node development have helped reveal similar requirements for spleen regeneration. These factors are now considered in the regulation of embryonic and postnatal spleen formation, and in the establishment of mature white pulp and marginal zone compartments which are essential for spleen-mediated immunity. A greater understanding of the cellular and molecular mechanisms which control spleen development will assist in the design of more precise and efficient tissue grafting methods for spleen regeneration on demand. Regeneration of organs which harbour functional white pulp tissue will also offer novel opportunities for effective immunotherapy against cancer as well as infectious diseases