Whole-Body Positron Emission Tomography with 18F-Fluorodeoxyglucose/Magnetic Resonance Imaging as a Screening Tool for the Detection of Malignant Transformation in Individuals with Neurofibromatosis Type 1.

Malignant peripheral nerve sheath tumors (MPNSTs) are the leading cause of death in patients with neurofibromatosis type 1. They can result from premalignant neurofibromas, including neurofibromas with atypia and atypical neurofibromatous neoplasms of uncertain biologic potential. Some phenotypic characteristics have been described as associated with their development. The aim of this study was to outline our use of whole-body positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging in adults with neurofibromatosis type 1, especially in the screening of asymptomatic individuals with a higher risk of developing an MPNST, and to study its impact on neurofibroma classification (malignant vs premalignant) and MPNST staging over time. Individuals with neurofibromatosis type 1 who underwent a positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging between 2017 and 2021 were included, analyzing separately the screened population. Maximum standard uptake value and diffusion-weighted imaging were assessed. Biopsy/surgery confirmed the diagnosis. In all, 345 positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging were performed in 241 patients, including 149 asymptomatic (62%) but at-risk patients. Eight MPNSTs in 8 screened individuals (5%), 6 neurofibromas with atypia in 4 individuals (3%), and 29 atypical neurofibromatous neoplasms of uncertain biologic potential in 23 individuals (15%) were diagnosed. Over time, the proportion of grade 3 MPNST and the malignant/premalignant ratio in screened individuals significantly decreased (P = .03 and P < .001, respectively). This study emphasizes the diagnostic and screening performances of whole-body positron emission tomography with 18F-fluorodeoxyglucose/magnetic resonance imaging in adults with neurofibromatosis type 1.

A core outcome domain set to assess cutaneous neurofibromas related to neurofibromatosis type 1 in clinical trials.

BACKGROUND: Cutaneous neurofibromas (cNF) are considered one of the highest burdens of neurofibromatosis type 1 (NF1). To date, no medical treatment can cure cNF or prevent their development. In that context, there is an urgent need to prepare and standardize the methodology of future trials targeting cNF. OBJECTIVES: The objective was to develop a core outcome domain set suitable for all clinical trials targeting NF1-associated cNF. METHODS: The validated approach of this work consisted of a three-phase methodology: (i) generating the domains [systematic literature review (SLR) and qualitative studies]; (ii) agreeing (three-round international e-Delphi consensus process and working groups); and (iii) voting. RESULTS: (i) The SLR and the qualitative studies (three types of focus groups and a French e-survey with 234 participants) resulted in a preliminary list of 31 candidate items and their corresponding definitions. (ii) A total of 229 individuals from 29 countries participated in the first round of the e-Delphi process: 71 patients, relatives or representatives (31.0%), 130 healthcare professionals (HCPs, 56.8%) and 28 researchers, representatives of a drug regulatory authority, industry or pharmaceutical company representatives or journal editors (12.2%). The overall participation rate was 74%. After round 2, five candidate items were excluded. Between rounds 2 and 3, international workshops were held to better understand the disagreements among stakeholders. This phase led to the identification of 19 items as outcome subdomains. (iii) The items were fused to create four outcome domains ('clinical assessment', 'daily life impact', 'patient satisfaction' and 'perception of health') and prioritized. The seven items that did not reach consensus were marked for the research agenda. The final core outcome domain set reached 100% of the votes of the steering committee members. CONCLUSIONS: Although numerous outcomes can be explored in studies related to cNF in NF1, the present study offers four outcome domains that should be reported in all trial studies, agreed on by international patients, relatives and representatives of patients; HCPs; researchers, representatives of drug regulatory authorities or pharmaceutical companies and journal editors. The next step will include the development of a set of core outcome measurement instruments to further standardize how these outcomes should be assessed.

Topical delivery of mitogen-activated protein kinase inhibitor binimetinib prevents the development of cutaneous neurofibromas in neurofibromatosis type 1 mutant mice.

Cutaneous neurofibromas (cNFs) are a hallmark of patients with the neurofibromatosis type 1 (NF1) genetic disorder. These benign nerve sheath tumors, which can amount to thousands, develop from puberty onward, often cause pain and are considered by patients to be the primary burden of the disease. Mutations of NF1, encoding a negative regulator of the RAS signaling pathway, in the Schwann cell (SCs) lineage are considered to be at the origin of cNFs. The mechanisms governing cNFs development are poorly understood, and therapeutics to reduce cNFs are missing, mainly due to the lack of appropriate animal models. To address this, we designed the Nf1-KO mouse model that develops cNFs. Using this model, we found that cNFs development is a singular event and goes through 3 successive stages: initiation, progression, and stabilization characterized by changes in the proliferative and MAPK activities of tumor SCs. We found that skin trauma accelerated the development of cNFs and further used this model to explore the efficacy of the MEK inhibitor binimetinib to cure these tumors. We showed that while topically delivered binimetinib has a selective and minor effect on mature cNFs, the same drug prevents their development over long periods.

cNF-Skindex in Adults Living with Neurofibromatosis 1: Severity Strata in France and Validation in United States Adults.

Cutaneous neurofibromas (cNF) contribute to the impairment of QOL in individuals with neurofibromatosis 1. The cNF-Skindex, validated in a French population, specifically assesses the cNF-related QOL. In this study, we first defined severity strata using an anchoring approach on the basis of patient's burden. In total, 209 patients answered the anchor question and the cNF-Skindex. We tested the agreement among the three strata, generated by all potential couples of cut-off values of the cNF-Skindex and the three strata defined in the anchor question. The cut-off values 12 and 49 provided the highest Kappa value (κ = 0.685, 95% confidence interval = 0.604-0.765). Second, we validated the score and the strata in a United States population using the answers provided by 220 French and 148 United States adults. In the multivariable linear regression analysis, the country of origin was not a factor associated with the score (P = 0.297). The number of cNF along the different severity strata was similar between the French and the United States populations. In conclusion, stratification constitutes a powerful tool to better interpret the cNF-Skindex in daily practice and in clinical trials. This study validates its use in two populations that together constitute a large cohort of patients willing to participate in clinical research.

In-Hospital Clinical Features, Morbidity, and Mortality of Patients with Neurofibromatosis 1 in France: A Nationwide, Population-Based Retrospective Cohort Study.

Neurofibromatosis 1 (NF1) is a multisystem disease that can affect nearly every organ system. The aim of our study was to describe the in-hospital population with NF1 in France. We conducted a nationwide retrospective cohort study using the French hospital administrative database. A total of 11,425 patients with NF1 (53.4% female, 19,080 person years) were identified from January 2013 to December 2019. A total of 23% had at least one diagnosis of a comorbidity or NF1-associated complication or disease, and it was highest in the age group of 10-15 years. A total of 2,601 (22.8%) had a diagnosis of cancer. There were 366 (3.2%) in-hospital deaths, and we observed a standardized mortality ratio of 4.14 (95% confidence interval = 3.71-4.56), with a higher standardized mortality ratio in women and in the age group of 10-15 years. The standardized incident ratio (SIR) of cancer was 10.3 (95% confidence interval = 9.6-11.1). We observed high SIR values for cancer in childhood, with a decrease toward that of the general population by age 70 years. We observed high SIRs for NF1-associated cancers: CNS SIR of 195.4 (95% confidence interval = 172.2-220.9) and small intestine SIR of 102.9 (95% confidence interval = 71.7-143.2). The study provides a better understanding of the prognosis in people living with NF1.

Bothnian Palmoplantar Keratoderma: Further Delineation of the Associated Phenotype.

Bothnian palmoplantar keratoderma (PPKB, MIM600231) is an autosomal dominant form of diffuse non-epidermolytic PPK characterized by spontaneous yellowish-white PPK associated with a spongy appearance after water-immersion. It is due to AQP5 heterozygous mutations. We report four patients carrying a novel AQP5 heterozygous mutation (c.125T>A; p.(Ile42Asn)), and belonging to the same French family. Early palmoplantar swelling (before one year of age), pruritus and hyperhidrosis were constant. The PPK was finally characterized as transgrediens, non-progrediens, diffuse PPK with a clear delineation between normal and affected skin. The cutaneous modifications at water-immersion test, "hand-in-the-bucket sign", were significantly evident after 3 to 6 min of immersion in the children and father, respectively. AQP5 protein is expressed in eccrine sweat glands (ESG), salivary and airway submucosal glands. In PPKB, gain of function mutations seem to widen the channel diameter of ESG and increase water movement. Thus, swelling seems to be induced by hypotonicity with water entrance into cells, while hyperhidrosis is the result of an increased cytosolic calcium concentration.

Eosinophilic Pustular Folliculitis of Infancy: A Histologic Assessment of 43 Cases.

ABSTRACT: Eosinophilic pustular folliculitis of infancy is a sterile, inflammatory dermatosis that mainly affects children younger than 36 months. The underlying physiopathologic mechanism is unclear. Clinical diagnosis is challenging, and a skin biopsy may be necessary. The literature data are sometimes contradictory, and a histologic series of eosinophilic pustular folliculitis of infancy cases has not been previously published.

Prior infection by seasonal coronaviruses, as assessed by serology, does not prevent SARS-CoV-2 infection and disease in children, France, April to June 2020.

BackgroundChildren have a low rate of COVID-19 and secondary severe multisystem inflammatory syndrome (MIS) but present a high prevalence of symptomatic seasonal coronavirus infections.AimWe tested if prior infections by seasonal coronaviruses (HCoV) NL63, HKU1, 229E or OC43 as assessed by serology, provide cross-protective immunity against SARS-CoV-2 infection.MethodsWe set a cross-sectional observational multicentric study in pauci- or asymptomatic children hospitalised in Paris during the first wave for reasons other than COVID (hospitalised children (HOS), n = 739) plus children presenting with MIS (n = 36). SARS-CoV-2 antibodies directed against the nucleoprotein (N) and S1 and S2 domains of the spike (S) proteins were monitored by an in-house luciferase immunoprecipitation system assay. We randomly selected 69 SARS-CoV-2-seropositive patients (including 15 with MIS) and 115 matched SARS-CoV-2-seronegative patients (controls (CTL)). We measured antibodies against SARS-CoV-2 and HCoV as evidence for prior corresponding infections and assessed if SARS-CoV-2 prevalence of infection and levels of antibody responses were shaped by prior seasonal coronavirus infections.ResultsPrevalence of HCoV infections were similar in HOS, MIS and CTL groups. Antibody levels against HCoV were not significantly different in the three groups and were not related to the level of SARS-CoV-2 antibodies in the HOS and MIS groups. SARS-CoV-2 antibody profiles were different between HOS and MIS children.ConclusionPrior infection by seasonal coronaviruses, as assessed by serology, does not interfere with SARS-CoV-2 infection and related MIS in children.

Cutaneous melioidosis: a review of the literature.

BACKGROUND: Melioidosis is mainly observed in South-East Asia, where Burkholderia pseudomallei is endemic. Cutaneous melioidosis (CM) has rarely been described and in contrast to systemic forms, there are no therapeutic recommendations to guide management. METHODS: We reviewed the literature published before January 2018, evaluating: dermatological presentation, natural history, diagnostic methods, and treatment options. We also distinguish between primary and secondary CM in which the infection first started in the skin or came from an extracutaneous localization, respectively, and chronic CM when duration exceeded 2 months. The recommended treatment for systemic forms included ceftazidime or meropenem, followed by oral maintenance therapy with cotrimoxazole or amoxicillin - clavulanic acid. RESULTS: Forty-three cases were published in 38 articles. Twenty-nine patients (67.4%) were travelers, including 13 (44.8%) returning from Thailand. Thirty-eight patients (88%) had primary CM, including nine (29.9%) with chronic infection. All cases of secondary CM first presented with acute infection. The median incubation time was 3 weeks. The most common presentation was cutaneous abscesses (58%). The recommended treatment was administered in 62.7% cases with 37.2% for maintenance therapy. Sixteen patients (37.2%) underwent surgery. Death was reported in less than 5%. CONCLUSION: CM should be considered in travelers returning from or residents of endemic countries, particularly Thailand, presenting with cutaneous abscesses, cellulitis, or ulcerations. Surgery may be necessary in a substantial proportion of patients and follow-up of at least 1 year is essential. Therapeutic recommendations need to be established.

KIF7 mutations cause fetal hydrolethalus and acrocallosal syndromes.

KIF7, the human ortholog of Drosophila Costal2, is a key component of the Hedgehog signaling pathway. Here we report mutations in KIF7 in individuals with hydrolethalus and acrocallosal syndromes, two multiple malformation disorders with overlapping features that include polydactyly, brain abnormalities and cleft palate. Consistent with a role of KIF7 in Hedgehog signaling, we show deregulation of most GLI transcription factor targets and impaired GLI3 processing in tissues from individuals with KIF7 mutations. KIF7 is also a likely contributor of alleles across the ciliopathy spectrum, as sequencing of a diverse cohort identified several missense mutations detrimental to protein function. In addition, in vivo genetic interaction studies indicated that knockdown of KIF7 could exacerbate the phenotype induced by knockdown of other ciliopathy transcripts. Our data show the role of KIF7 in human primary cilia, especially in the Hedgehog pathway through the regulation of GLI targets, and expand the clinical spectrum of ciliopathies.