Assessment of BRAFV600E mutation in pulmonary Langerhans cell histiocytosis in tissue biopsies and bronchoalveolar lavages by droplet digital polymerase chain reaction.

The neoplastic nature of pulmonary Langerhans cell histiocytosis (PLCH) is still debated. As the detection of BRAF V600E and MAP2K1 mutations in patients with PCLH is now considered for such assessment, the aim of our study was to evaluate digital droplet polymerase chain reaction (ddPCR) in PCLH diagnosis. We retrospectively analyzed BRAFV600E detection in a cohort of 42 PCLH tissues and 18 bronchoalveolar lavages (BALs) by ddPCR, immunohistochemistry, high-resolution melting PCR (HRM), and next-generation sequencing (NGS). The presence of BRAFV600E mutation was assessed by at least two concordant techniques to further evaluate specificity and sensitivity of each method. The BRAF V600E mutation prevalence was detected in 18 out of 41 cases by ddPCR, 10 out of 36 cases by HRM PCR, and 16 out of 31 cases by NGS. BRAFV600E immunohistochemistry sensitivity was 94%, and specificity was 79%. HRM PCR sensitivity was only 59%, and specificity was 100%. NGS sensitivity and specificity were 100% for interpretable cases (n = 31), but in 11 cases, this technique was non-contributive. The analysis of BAL samples by ddPCR revealed a BRAFV600E mutation both in tissue and in BAL samples in one patient, a wild-type status both in tissue and in BAL samples in two patients, and a wild-type BRAF status in BAL and a BRAFV600E mutation in tissue samples in four patients. The study supports the usefulness of ddPCR for BRAF status assessment in either tissue or BAL samples to increase the accuracy of PLCH diagnosis.

[Sudden death of a young man as late sequelae complicating a pediatric disease: About a case]. / Mort subite d'un homme jeune dans le cadre de séquelles tardives d'une pathologie pédiatrique : à propos d'un cas.

In France, sudden death is responsible every year for 40,000 deaths. The most frequent etiology is cardiac disease. Atheromatous-related pathology is the most common etiology beyond 35, but cardiomyopathies and channelopathies are responsible for a significant number of deaths in young adults. Some acquired disorders can also cause sudden cardiac death. We report the case of a 17-year-old man who died suddenly after sport. Autopsy and pathological study found multiple giant coronary aneurysms. Thrombosis and fibrous scar of myocardial ischemic events were observed. These lesions were in favor of late sequelae of Kawasaki disease. Kawasaki disease is a rare but not exceptional cause of sudden cardiac death in young adults. In the lack of known clinical history, some aspects, even not specific, should evoke this diagnosis. Even in front of apparent good clinical tolerance, these sequelae require appropriate follow-up because of a significant risk of sudden death.

Endoscopic and histologic response to cyclosporine in ulcerative colitis and their impact on disease outcome: A cohort study.

INTRODUCTION: Cyclosporine (CsA) is an effective agent for treating patients with acute steroid-refractory ulcerative colitis (UC). The aim was to assess endoscopic and histologic responses to CsA and to determine their predictive value on UC outcome. PATIENTS AND METHODS: Consecutive UC patients who received intravenous CsA for an acute refractory UC were included when they had endoscopic assessments with biopsies at entry and, at CsA interruption in responders. Mucosal healing (MH) was defined by Mayo endoscopic subscore ≤1 and, histologic response (HR) by the absence of basal plasmocytosis or a Geboes score <3.1. RESULTS: Among 21 patients who responded to CsA, MH was achieved in 81%. Survival rates without relapse at 2 years were 79% and 25% in patients with MH and without MH, respectively (p=0.04). HR was observed in 84% of patients according to basal plasmocytosis and in 68% according to Geboes score. Multivariate analysis revealed that a Mayo endoscopic subscore of 0 was the only prognostic factor associated with absence of relapse (RR=12; 95%CI: 1.05-136.79). CONCLUSION: CsA provides MH and HR in most of UC patients responding to this drug. As suggested with other UC treatments, a complete MH with CsA has a good prognostic value.

Polypoid laryngeal inflammatory myofibroblastic tumors: misleading lesions: description of six cases showing ALK overexpression.

OBJECTIVES: Laryngeal inflammatory myofibroblastic tumors (IMTs) are rarely reported in the literature but may be underrecognized. To better characterize their features, we report a series of six cases. METHODS: The clinicopathologic findings, including immunohistochemistry, fluorescence in situ hybridization (FISH) analysis, and follow-up, were evaluated and a review of the literature was performed. RESULTS: These cases presented as small polypoid vocal cord or ventricular band lesions, with a more advanced mean age at diagnosis (49 years) than typically reported in other localizations. Apart from one secondary revision surgery, no complementary treatment and no recurrences were observed. Histologically, various morphologic features were seen. All tumors were spindle cell proliferations on a myxoid background with more or less atypia and significant inflammatory infiltrate. All six cases showed anaplastic lymphoma kinase (ALK) immunohistochemical expression. FISH rearrangement was present in four of six cases. Only two cases were initially diagnosed as IMT. CONCLUSIONS: According to our series, laryngeal IMTs are easily misdiagnosed. They have a good prognosis, and ALK immunohistochemistry should be carried out to assess this diagnosis when spindle cell proliferations are observed in this localization.