Lococo, Filippo

Abstract Rationale: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a pulmonary condition characterised by neuroendocrine cell proliferation along respiratory bronchioles resulting in tumourlet formation which may progress to pulmonary carcinoid. DIPNECH is a rare and under-recognised condition that predominantly affects females, with an estimated worldwide incidence of 5-6 people per million population. Given it's rarity and the poor understanding around the pathogenesis and treatment of this condition, we undertook the largest international case series to date of DIPNECH patients. We aim to further characterise this patient cohort to better understand the clinical features, identify common pulmonary function test (PFT) patterns and radiographic findings and describe current treatment practices. Methods: We collated data from 17 centres across 8 different countries comprising a total of 258 patients. Data collected included patient demographics, smoking history, symptoms, co-morbidities, pathological diagnosis, imaging findings, PFT pattern and therapies. Results: In total 258 patients were identified. The median age was 65 (SD+/- 10.6). 241 (93%) were female. 39% (n= 94/243) were ex-smokers. 79% (n=186/234) of patients reported pulmonary symptoms with cough being the most common symptom reported in 81% (n=151/186) of patients. Many patients were polysymptomatic, with cough and dyspnoea being the most common combination of symptoms described. (50.54%; n=94/186). Complete spirometry pattern was documented for 180 patients (69.78%) with an obstructive pattern being the most commonly observed (n=76/180; 42%). 27.5% (n=41/139) had clinically significant FEV1 reversibility post bronchodilator administration. Pathology specimens were available in 219 cases. Most common pathological features were neuroendocrine hyperplasia which was observed in 75% (n=165/219) and tumourlets in 74% (n=162/219) of cases. Carcinoid, either typical or atypical, was observed in 64% (n=141/219) of samples. 252 patients had computed tomography (CT) imaging performed. Pulmonary nodules were the most common feature identified in 99.60% of cases (248/250). Mosaic attenuation (69.30%; n=50/173) and airway dilatation (28.90%; n=50/173) were also frequently reported. There was no significant correlation between symptoms (cough, dyspnoea, wheeze) and airway dilatation (p=0.496), mosaic attenuation (p=0.496) and PFT pattern (p=0.837). There was a significant association between presence of symptoms and mosaic attenuation on CT (p=0.003). Conclusions: DIPNECH, while a rare disorder, is understudied. This international case series is the largest performed to date and highlights the complexity in management of these patients.

Background:Mutations localized in the tyrosine kinase domain activation loop of FLT3 (FLT3‐TKD), induce constitutive tyrosine phosphorylation, and activation of the receptor tyrosine kinase similarly to FLT3 internal tandem duplication (ITD) mutations. However, the prognostic role of FLT3‐TKD in AML is not well established. In the phase 3 RATIFY trial [CALGB 10603/Alliance; NCT00651261; Stone et al. N Engl J Med. 2017] midostaurin, in combination with standard chemotherapy, improved survival outcomes across all three FLT3 stratification subgroups (ITD high allelic ratio (AR) [≥ 0.7], ITD low AR [< 0.7] and TKD) vs placebo.Aims:Here, a post hoc analysis was used to establish the efficacy of midostaurin in patients (pts) in the RATIFY trial stratified by FLT3‐TKD AR and NPM1 mutational status.Methods:In RATIFY, newly diagnosed pts with AML 18–60 years (y) old were randomly assigned to receive midostaurin or placebo together with standard induction and consolidation therapy followed by twelve 28‐day cycles of maintenance therapy with midostaurin or placebo. FLT3‐TKD mutation was detected by PCR and capillary electrophoresis at nine reference laboratories. The FLT3‐TKD AR was calculated as the ratio between the areas under the curve of mutant to wild‐type allele. Pts were categorized as NPM1 mutated (mut) or NPM1 wild‐type (WT) using PCR. Efficacy outcomes included complete remission (CR), overall survival (OS), event‐free survival (EFS) and disease‐free survival (DFS). EFS and DFS analyses were performed considering CR within a 60‐day window. P values presented were not adjusted for multiplicity.Results:Of 163 FLT3‐TKD pts, 134 with available NPM1 data had consented for exploratory analysis and were included in this study. Overall, 58.9% of pts had NPM1‐mut, 47.8% were male and the median age was 49 y (range: 19.3–59.9 y). The median white blood cell (WBC) count was higher in pts with NPM1‐mut than in pts with NPM1‐WT (34.1 vs 15.5 × 109 /L). The median FLT3‐TKD AR was 0.4 (range: 0–2.7). Overall CR rate (regardless of NPM1 genotype) was 64% for midostaurin and 56% for placebo in FLT3‐TKD pts. Pts with FLT3‐TKD AR ≥ 0.4 treated with midostaurin showed a trend towards improved OS and reduced cumulative incidence of relapse (CIR) (Figure). In FLT3‐TKD AR ≥ 0.4 pts, the presence of a NPM1 mutation had a significant prognostic effect for all endpoints consistently with hazard ratios (HRs) around 0.50 or lower. Regardless of treatment OS, EFS, and DFS estimates at 3 y were 73% vs 52%, 48% vs 25%, and 74% vs 47%, respectively, for the 45 pts with FLT3‐TKD/NPM1‐mut vs the 25 pts with FLT3‐TKD/NPM1‐WT. It should be noted that the number of pts in each subgroup was small. Multivariate analyses in these FLT3‐TKD pts revealed that NPM1 genotype was an independent prognostic factor for OS and EFS (2‐sided P < 0.05), whereas study drug, age, sex, TKD AR, WBC at baseline and stem cell transplantation (SCT) (no/yes) did not reach this level of significance in the Cox model.Summary/Conclusion:This post hoc analysis of the subset of FLT3‐TKD pts in the RATIFY trial showed the high prognostic value of NPM1 mutational status. Midostaurin showed an overall benefit in the FLT3‐TKD pts for OS, EFS, CR and DFS, with the impact of treatment on outcome for NPM1‐mut pts being greatest in those with higher FLT3‐TKD allelic burden. U10CA180821, U10CA180882, U24CA196171, U10CA180861; Novartis; htt∗∗∗ps://acknowledgments.alliancefound.orgimage

AimErdheim–Chester disease represents a clonal systemic proliferation of histiocytes. Bone is the most common site of involvement, although almost any organ, including the lungs, can be affected.Methods and resultsThe diagnosis of Erdheim–Chester disease can be difficult, owing to its rarity and protean presentation. Correlation between clinical, radiological and histological findings is mandatory for identification of the disease. Foamy histiocytes, lacking Langerhans cell markers, represent the typical histological findings, although their absence does not rule out Erdheim–Chester disease. Identification of BRAF mutation can be helpful in making the diagnosis, and allows for the development and application of targeted therapies in this setting.ConclusionsHerein, we describe two cases presenting with lung involvement and vertebral lesions, lacking the more typical long‐bone involvement. One case histologically mimicked Rosai–Dorfman disease. However, both cases harboured the pathognomonic BRAFV600E mutation.

The diagnostic criteria of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) are not well defined, and DIPNECH can be mistaken for carcinoids associated with neuroendocrine cell hyperplasia (NECH). In this study, we compared clinical, radiologic, histologic, immunohistochemical, and molecular features of DIPNECH and isolated carcinoids with/without NECH. The study population included 151 cases (77 female patients and 74 male patients), 19 with DIPNECH and 132 with carcinoids with/without NECH. None of the cases displayed molecular alterations or anaplastic lymphoma kinase expression. Compared with individuals with carcinoids with/without NECH, patients with DIPNECH were more likely to be female individuals ( P <0.0001), nonsmokers ( P =0.021), and symptomatic, and to have an obstructive/mixed respiratory defect, peripheral location of the lesions, and air trapping ( P <0.0001) on chest computed tomography, and constrictive bronchiolitis on histology ( P <0.0001). Among immunohistochemical markers, DIPNECH was associated with higher expression of thyroid transcription factor-1, CD10, and gastrin-releasing peptide/bombesin-like peptide ( P <0.0001). Yet, when a purely histopathologic definition of DIPNECH was applied, 40% of isolated carcinoids also met the diagnostic criteria for DIPNECH, even in the absence of symptoms and/or radiologic abnormalities. Therefore, as DIPNECH represents a distinct clinical syndrome, we suggest the term DIPNECH be limited to cases presenting with respiratory symptoms, functional and/or radiologic abnormalities, and constrictive bronchiolitis on histology.