Validity and interexaminer reliability of a new method to quantify skin neurofibromas of neurofibromatosis 1 using paper frames

Current and Emerging Imaging Techniques for Neurofibromatosis Type 1-Associated Cutaneous Neurofibromas

A consistent set of measurement techniques must be applied to reliably and reproducibly evaluate the efficacy of treatments for cutaneous neurofibromas (cNFs) in people with neurofibromatosis type 1 (NF1). cNFs are neurocutaneous tumors that are the most common tumor in people with NF1 and represent an area of unmet clinical need. This review presents the available data regarding approaches in use or development to identify, measure, and track cNFs, including calipers, digital imaging, and high-frequency ultrasound sonography. We also describe emerging technologies such as spatial frequency domain imaging and the application of imaging modalities such as optical coherence tomography that may enable the detection of early cNFs and prevention of tumor-associated morbidity.

Head circumference and anthropometric changes and their relation to plexiform and skin neurofibromas in sporadic and familial neurofibromatosis 1 Brazilian adults: a cross-sectional study

Background

Neurofibromatosis 1 (NF1) is a common autosomal dominant syndrome with complete penetrance and highly variable expressivity. The cutaneous neurofibroma (Cnf) and plexiform neurofibroma (Pnf), café-au-lait spots, and freckle-like lesions are common in NF1, but many other manifestations can occur. We aimed to evaluate head circumference, height, weight, body mass index (BMI), head circumference-to-height ratio (HCHR) and waist–hip ratio (WHR) in adult NF1 Brazilian individuals versus a paired control group and investigate their correlation with the presence of clinically visible Pnfs, and number of “skin neurofibromas” (Snf), which include both cutaneous and subcutaneous neurofibromas.

Methods

A case–control study was conducted with 168 individuals, 84 with NF1 and 84 without NF1, paired by sex and age. Head circumference and anthropometric measurements, Snf quantification, evaluation of clinically visible Pnf and familial inheritance were accessed.

Results

Prevalence of macrocephaly was significantly higher in NF1 women. Height and weight were significantly lower in both males and females with NF1. HCHR was higher in the NF1 group than in the control group for both sexes. BMI was significantly lower in men with NF1. Waist and hip circumferences were significantly reduced in NF compared with the controls, but the mean WHR was significantly lower only in NF1 women. No correlation was found between the Snf and head circumference and anthropometric measurements, sex or family history. The presence and larger size of clinically visible plexiform neurofibromas were associated with normal stature (p = 0.037 and p = 0.003, respectively).

Conclusions

NF1 individuals have increased prevalence of macrocephaly, short stature, low BMI, and reduced abdominal fat. There is no relation between head circumference and anthropometric data with family history, or neurofibromas.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02482-8.

Estimated Mask Use and Temporal Relationship to COVID-19 Epidemiology of Black Lives Matter Protests in 12 Cities

There is an increased risk of SARS-CoV-2 transmission during mass gatherings and a risk of asymptomatic infection. We aimed to estimate the use of masks during Black Lives Matter (BLM) protests and whether these protests increased the risk of COVID-19. Two reviewers screened 496 protest images for mask use, with high inter-rater reliability. Protest intensity, use of tear gas, government control measures, and testing rates were estimated in 12 cities. A correlation analysis was conducted to assess the potential effect of mask use and other measures, adjusting for testing rates, on COVID-19 epidemiology 4 weeks (two incubation periods) post-protests. Mask use ranged from 69 to 96% across protests. There was no increase in the incidence of COVID-19 post-protest in 11 cities. After adjusting for testing rates, only Miami, which involved use of tear gas and had high protest intensity, showed a clear increase in COVID-19 after one incubation period post-protest. No significant correlation was found between incidence and protest factors. Our study showed that protests in most cities studied did not increase COVID-19 incidence in 2020, and a high level of mask use was seen. The absence of an epidemic surge within two incubation periods of a protest is indicative that the protests did not have a major influence on epidemic activity, except in Miami. With the globally circulating highly transmissible Alpha, Delta, and Omicron variants, layered interventions such as mandated mask use, physical distancing, testing, and vaccination should be applied for mass gatherings in the future.

A Clinicopathologic Study on the Role of Estrogen, Progesterone, and Their Classical and Nonclassical Receptors in Cutaneous Neurofibromas of Individuals With Neurofibromatosis 1

OBJECTIVES

To evaluate the expression of progesterone receptor (PR), estrogen receptor (ER), and G protein-coupled estrogen receptor 1 (GPER-1) in cutaneous neurofibromas (cNFs) and their correlation with demographic, clinical, and laboratory data of individuals with neurofibromatosis 1 (NF1). The association of PROGINS polymorphism and PR expression in cNFs, as well as the serum steroidal hormones and the number of cNFs, was investigated.

METHODS

The sample comprised 80 large and 80 small cNFs from 80 individuals with NF1. PR, ER, GPER-1, and Ki-67 expression were investigated by immunohistochemistry in tissue micro- and macroarrays and quantified using a digital computer-assisted method. The number of cNFs, the levels of serum 17β estradiol and progesterone, and the PROGINS polymorphism were identified.

RESULTS

Twelve (8.5%) small cNFs were weakly positive for ER, 131 (92.3%) cNFs expressed PR, and all (100%) cNFs expressed GPER-1. Large cNFs showed a higher expression of PR (P < .0001) and GPER-1 (P = .019) and had a higher intensity of staining for these receptors (P < .0001). The cell proliferation index was positively correlated with PR (P = .001). Persons with more cNFs had higher serum levels of progesterone (P = .001).

CONCLUSIONS

These findings emphasize the role of estrogen and progesterone in cNF development and suggest that these hormones may act on cNF cells via a noncanonical pathway through GPER-1.

Clinical trial design for cutaneous neurofibromas

OBJECTIVE

Several clinical trials targeting cutaneous neurofibromas (cNF) have been conducted; however, none has resulted in meaningful changes to care. The Clinical Trial Design and Development subgroup's goals were to (1) define key considerations in the design of clinical trials for cNF, (2) summarize existing data in relation to these considerations, and (3) provide consensus recommendations about key elements of trial design to accelerate the clinical development of therapies for cNF.

METHODS

The subgroup, with experts from genetics, dermatology, neurology, oncology, and basic science, spanning academia, government research, and regulatory programs, and industry, reviewed published and unpublished data on clinical trials for cNF and other diseases in the skin. Discussions of these data resulted in formulation of a list of priority issues to address in order to develop efficient and effective clinical trials for cNF.

RESULTS

The subgroup identified 2 natural history studies of cNF, 4 priority outcome measures, and 6 patient-reported outcome tools for potential use in efficacy trials of cNF. Time to initiate intervention, patient eligibility, mechanism of action, route of administration, safety monitoring, and regulatory agency interactions were identified as key factors to consider when designing clinical trials for cNF.

CONCLUSIONS

Alignment on endpoints and methods for the measurement and quantification of cNF represent a priority for therapeutic development for cNF. Advances in technological methods and outcome tools utilized in other skin diseases may be applicable to cNF studies. Patient age is an important factor guiding trial design and clinical development path.

Cutaneous neurofibromas in Neurofibromatosis type I: a quantitative natural history study

Background

Neurofibromatosis type 1 (NF1) is a genetic disorder characterized by a predisposition to develop multiple benign tumors. A major feature of NF1 is the development of localized cutaneous neurofibromas. Cutaneous neurofibromas manifest in > 99% of adults with NF1 and are responsible for major negative effects on quality of life. Previous reports have correlated increased burden of cutaneous neurofibromas with age and pregnancy, but longitudinal data are not available to establish a quantitative natural history of these lesions. The purpose of this study is to conduct a prospective natural history study of 22 adults with NF1 over an 8-year period to quantify cutaneous neurofibroma number and size.

Results

The average monthly increase in volume for cutaneous neurofibromas was 0.37 mm³ in the back region (95% CI (0.23, 0.51), p < 0.0001), 0.28 mm³ in the abdominal region (95% CI (0.16, 0.41), p < 0.0001), and 0.21 mm³ in the arm/leg region (95% CI (0.08, 0.34), p = 0.0022). The number of cutaneous neurofibromas significantly increased in the back (slope = 0.032, p = 0.011) and abdominal (slope = 0.018, p = 0.026) regions, while the leg/arm regions retained a positive trend (slope = 0.004, p = 0.055).

Conclusions

The number and volume of cutaneous neurofibromas significantly increased over an 8-year timespan; however, the rate of increase is variable by individual and body region. These findings may provide insight into cutaneous neurofibroma development and benefit researchers considering clinical trials targeting cutaneous neurofibromas.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0772-z) contains supplementary material, which is available to authorized users.

Emerging genotype-phenotype relationships in patients with large NF1 deletions

The most frequent recurring mutations in neurofibromatosis type 1 (NF1) are large deletions encompassing the NF1 gene and its flanking regions (NF1 microdeletions). The majority of these deletions encompass 1.4-Mb and are associated with the loss of 14 protein-coding genes and four microRNA genes. Patients with germline type-1 NF1 microdeletions frequently exhibit dysmorphic facial features, overgrowth/tall-for-age stature, significant delay in cognitive development, large hands and feet, hyperflexibility of joints and muscular hypotonia. Such patients also display significantly more cardiovascular anomalies as compared with patients without large deletions and often exhibit increased numbers of subcutaneous, plexiform and spinal neurofibromas as compared with the general NF1 population. Further, an extremely high burden of internal neurofibromas, characterised by >3000 ml tumour volume, is encountered significantly, more frequently, in non-mosaic NF1 microdeletion patients than in NF1 patients lacking such deletions. NF1 microdeletion patients also have an increased risk of malignant peripheral nerve sheath tumours (MPNSTs); their lifetime MPNST risk is 16–26%, rather higher than that of NF1 patients with intragenic NF1 mutations (8–13%). NF1 microdeletion patients, therefore, represent a high-risk group for the development of MPNSTs, tumours which are very aggressive and difficult to treat. Co-deletion of the SUZ12 gene in addition to NF1 further increases the MPNST risk in NF1 microdeletion patients. Here, we summarise current knowledge about genotype–phenotype relationships in NF1 microdeletion patients and discuss the potential role of the genes located within the NF1 microdeletion interval whose haploinsufficiency may contribute to the more severe clinical phenotype.