Excision of Solitary Non-syndromic Oral Plexiform Neurofibroma Utilizing a Diode Laser: A Case Report.

Plexiform neurofibroma is a benign peripheral nerve sheath tumor known to be pathognomonic for neurofibromatosis type 1. However, solitary plexiform neurofibroma in the oral cavity is extremely rare. Herein, we presented a 73-year-old Saudi male with solitary plexiform neurofibroma located on the maxillary alveolar ridge, which was excised successfully using a 940 nm diode laser. Microscopic examination revealed a multinodular arrangement of benign spindle cells in a haphazard pattern. Immunohistochemical analysis showed positive staining for S100 and CD34 in the tumor cells.

Case report: Remarkable efficacy of negative-pressure wound therapy in giant lower extremity elephantiasis neuromatosa for vascularization, skin grafting, and fluid control.

INTRODUCTION AND IMPORTANCE: Neurofibromatosis type 1 is a benign peripheral nerve tumor, often manifests as plexiform neurofibroma that may cause severe dysfunction, pain, and disfigurement. Bleeding has been reported as a complication of plexiform neurofibroma due to vascular fragility and vasculopathy that may develop into life-threatening bleeding especially after excision procedure. Consequently, post excision complications also include dehiscence and infection. CASE PRESENTATION: We report a 23-year-old male with elephantiasis of the left lower extremity due to giant plexiform neurofibroma who underwent preoperative embolization followed by serial surgical mass reduction. There were postoperative complications consisting of hematoma, wound dehiscence, and infection. CLINICAL DISCUSSION: Negative pressure wound therapy is often used to accelerate wound healing, including infected wounds. However, negative pressure wound therapy has been a debatable modality for wound care of neurofibroma due to reported risks of profuse bleeding during its use. CONCLUSION: In this case, despite the size, negative-pressure wound therapy has shown good results for infected neurofibroma wounds and as an adjunct as wound dressing for defect closure of neurofibroma with split-thickness skin graft.

Silver Nanoparticles Selectively Treat Neurofibromatosis Type 1-Associated Plexiform Neurofibroma Cells at Doses That Do Not Affect Patient-Matched Schwann Cells.

Neurofibromatosis Type 1 (NF1) is a common neurogenic condition characterized by heterozygous loss of function mutations in the neurofibromin gene. NF1 patients are susceptible to the development of neurofibromas, including plexiform neurofibromas (pNFs), which occurs in about half of all cases. Plexiform neurofibroma are benign peripheral nerve sheath tumors originating from Schwann cells after complete loss of neurofibromin; they can be debilitating and also transform into deadly malignant peripheral nerve sheath tumors (MPNSTs). Here, our data indicates that silver nanoparticles (AgNPs) may be useful in the treatment of pNFs. We assessed the cytotoxicity of AgNPs using pNF cells and Schwann cells derived from the same NF1 patient. We found that AgNPs are selectively cytotoxic to pNF cells relative to isogenic Schwann cells. We then examined the role of neurofibromin expression on AgNP-mediated cytotoxicity; restoration of neurofibromin expression in pNF cells decreased sensitivity to AgNP, and knockdown of neurofibromin in isogenic Schwann cells increased sensitivity to AgNP, outlining a correlation between neurofibromin expression and AgNP-mediated cytotoxicity. AgNP was able to selectively remove pNF cells from a co-culture with patient-matched Schwann cells. Therefore, AgNPs represent a new approach for clinical management of NF1-associated pNF to address significant clinical need.

The NF1+/- Immune Microenvironment: Dueling Roles in Neurofibroma Development and Malignant Transformation.

Neurofibromatosis type 1 (NF1) is a common genetic disorder resulting in the development of both benign and malignant tumors of the peripheral nervous system. NF1 is caused by germline pathogenic variants or deletions of the NF1 tumor suppressor gene, which encodes the protein neurofibromin that functions as negative regulator of p21 RAS. Loss of NF1 heterozygosity in Schwann cells (SCs), the cells of origin for these nerve sheath-derived tumors, leads to the formation of plexiform neurofibromas (PNF)-benign yet complex neoplasms involving multiple nerve fascicles and comprised of a myriad of infiltrating stromal and immune cells. PNF development and progression are shaped by dynamic interactions between SCs and immune cells, including mast cells, macrophages, and T cells. In this review, we explore the current state of the field and critical knowledge gaps regarding the role of NF1(Nf1) haploinsufficiency on immune cell function, as well as the putative impact of Schwann cell lineage states on immune cell recruitment and function within the tumor field. Furthermore, we review emerging evidence suggesting a dueling role of Nf1+/- immune cells along the neurofibroma to MPNST continuum, on one hand propitiating PNF initiation, while on the other, potentially impeding the malignant transformation of plexiform and atypical neurofibroma precursor lesions. Finally, we underscore the potential implications of these discoveries and advocate for further research directed at illuminating the contributions of various immune cells subsets in discrete stages of tumor initiation, progression, and malignant transformation to facilitate the discovery and translation of innovative diagnostic and therapeutic approaches to transform risk-adapted care.

The PlexiQoL, a patient-reported outcome measure on quality of life in neurofibromatosis type 1-associated plexiform neurofibroma: translation, cultural adaptation and validation into the Dutch language for the Netherlands.

BACKGROUND: Half of the patients with Neurofibromatosis type 1 (NF1) develop one or more tumours called plexiform neurofibromas, which can have a significant impact on Quality of Life (QoL). The PlexiQoL questionnaire is a disease-specific QoL measure for adults with NF1-associated plexiform neurofibromas. The aim of this study was to adapt and validate a Dutch version of the PlexiQoL for the Netherlands. METHODS: The PlexiQoL was translated using the dual-panel methodology, followed by cognitive debriefing interviews to assess face and content validity. The psychometric properties were evaluated by administering the questionnaire on two separate occasions to a sample of adults with NF1 and plexiform neurofibromas. Feasibility was evaluated by the presence of floor/ceiling effects. Reliability was assessed by evaluating Cronbach's alpha coefficient and test-retest reliability, using Spearman's rank correlation coefficients. Mann-Whitney U tests were used to check for known group validity. The Nottingham Health Profile (NHP) questionnaire was used as comparator questionnaire to evaluate convergent validity. RESULTS: The translation and cognitive debriefing interviews resulted in a Dutch version of the PlexiQoL that reflected the original concept and underlying semantic meanings of the UK English version. Forty participants completed the validation survey. The Dutch PlexiQoL demonstrated excellent internal consistency (Cronbach's α 0.825) and test-retest reliability (Spearman correlation coefficient 0.928). The questionnaire detected differences in PlexiQoL scores between participants based on self-reported general health and disease severity. Convergent validity was confirmed for relevant NHP subsections. CONCLUSIONS: The Dutch PlexiQoL demonstrated excellent psychometric properties and can be reliably used to measure plexiform neurofibroma-related QoL in adults with NF1 in the Netherlands.

Use of the subfascial plane in debulking an extensive lower extremity plexiform neurofibroma: A case report.

INTRODUCTION: Plexiform neurofibromas (PNs) are characterized by their diffuse masses with tortuous expansion along nerve branches. While surgery is the primary management for PNs, the optimal surgical approach remains unestablished. CASE PRESENTATION: A 35-year-old lady presented with a large hanging mass covering the medial aspect of the thigh and the leg. It caused discomfort, disfigurement, and occasional pain. The patient was planned for the debulking surgery under spinal anesthesia. Incisions were given on the normal-looking skin adjacent to the mass, through the skin layers, subcutaneous tissue and deep fascia until the muscles were seen. The mass was then approached and elevated in the subfascial plane (relatively avascular). Large, dilated, dense tortuous vessels could be seen in the suprafascial and subcutaneous planes. Maximum area that could be removed was marked and excised. The normal contour of the left lower extremity was restored close to achieving a thigh and a leg lift. DISCUSSION: PNs pose surgical challenges due to their vascularity and difficult locations. The subfascial debulking approach presented in the case aims to reduce intraoperative hemorrhage by avoiding highly vascular areas and preventing entry into blood sinuses within the neurofibromatous tissue. This technique also minimizes the risk of inadvertent injury to nearby neurovascular structures. CONCLUSION: The proposed subfascial approach, significantly reduces intraoperative hemorrhage during the debulking of a PN.

The management of neurofibromatosis type 1 (NF1) in children and adolescents.

INTRODUCTION: Neurofibromatosis type 1 (NF1) is a rare neurogenetic disorder characterized by multiple organ system involvement and a predisposition to benign and malignant tumor development. With revised NF1 clinical criteria and the availability of germline genetic testing, there is now an opportunity to render an early diagnosis, expedite medical surveillance, and initiate treatment in a prompt and targeted manner. AREAS COVERED: The authors review the spectrum of medical problems associated with NF1, focusing specifically on children and young adults. The age-dependent appearance of NF1-associated features is highlighted, and the currently accepted medical treatments are discussed. Additionally, future directions for optimizing the care of this unique population of children are outlined. EXPERT OPINION: The appearance of NF1-related medical problems is age dependent, requiring surveillance for those features most likely to occur at any given age during childhood. As such, we advocate a life stage-focused screening approach beginning in infancy and continuing through the transition to adult care. With early detection, it becomes possible to promptly institute therapies and reduce patient morbidity. Importantly, with continued advancement in our understanding of disease pathogenesis, future improvements in the care of children with NF1 might incorporate improved risk assessments and more personalized molecularly targeted treatments.

Written language achievement in children and adolescents with neurofibromatosis type 1 and Plexiform Neurofibromas.

Neurofibromatosis type 1 (NF1) is associated with below average writing achievement. However, little is known about specific aspects of written language impacted by NF1, changes in writing over time, and associations between cognitive aspects of the NF1 phenotype and writing. At three timepoints over six years, children with NF1 and plexiform neurofibromas (PNs) completed Woodcock-Johnson tests of writing mechanics (Spelling, Punctuation & Capitalization, handwriting), written expression of ideas (Writing Samples), writing speed (Writing Fluency), and tests of general cognitive ability, executive function, memory, and attention. Children (N = 76, mean age = 12.8 ± 3.4 years) completed at least one baseline writing subtest. Overall writing scores were in the Average range (M = 93.4, SD = 17.4), but lower than population norms (p = 0.002). Scores were highest on Writing Samples (M = 95.2, SD = 17.3), and lowest for Punctuation & Capitalization (M = 87.9, SD = 18.8, p = 0.034). Writing scores were mostly stable over time. Nonverbal reasoning was related to some tests of writing mechanics and written expression of ideas. Short-term memory and inattention explained additional variance in Writing Samples and Spelling. Poor handwriting was associated with writing content beyond the impact of cognitive factors. Children with NF1 and PNs may benefit from early screening and writing support. Interventions should address the contribution of both cognitive and handwriting difficulties in written language.

Isolated Sacrococcygeal Plexiform Neurofibroma in a Child.

This case report describes a 4-year-old girl with an isolated neurofibroma in the sacrococcygeal region. Although initially resembling sacrococcygeal teratoma, histopathology revealed a benign nerve sheath tumor. Wide local excision was performed, and the final diagnosis was plexiform neurofibroma. Diagnostic challenges in rare childhood tumors require stepwise evaluation and multidisciplinary team discussions.

Development of a semi-automatic segmentation technique based on mean magnetic resonance imaging intensity thresholding for volumetric quantification of plexiform neurofibromas.

Rationale and objectives: Plexiform neurofibromas (PNs) are peripheral nerve tumors that occur in 25-50 % of patients with neurofibromatosis type 1. PNs may have complex, diffused, and irregular shapes. The objective of this work was to develop a volumetric quantification method for PNs as clinical assessment is currently based on unidimensional measurement. Materials and methods: A semi-automatic segmentation technique based on mean magnetic resonance imaging (MRI) intensity thresholding (SSTMean) was developed and compared to a similar and previously published technique based on minimum image intensity thresholding (SSTMini). The performance (volume and computation time) of the two techniques was compared to manual tracings of 15 tumors of different locations, shapes, and sizes. Performance was also assessed using different MRI sequences. Reproducibility was assessed by inter-observer analysis. Results: When compared to manual tracing, quantification performed with SSTMean was not significantly different (mean difference: 1.2 %), while volumes computed by SSTMini were significantly different (p < .0001, mean difference: 13.4 %). Volumes quantified by SSTMean were also significantly different than the ones assessed by SSTMini (p < .0001). Using SSTMean, volumes quantified with short TI inversion recovery, T1-, and T2-weighted imaging were not significantly different. Computation times used by SSTMean and SSTMini were significantly lower than for manual segmentation (p < .0001). The highest difference measured by two users was 8 cm3. Conclusion: Our method showed accuracy compared to a current gold standard (manual tracing) and reproducibility between users. The refined segmentation threshold and the possibility to define multiple regions-of-interest to initiate segmentation may have contributed to its performance. The versatility and speed of our method may prove useful to better monitor volumetric changes in lesions of patients enrolled in clinical trials to assessing response to therapy.

Giant gluteal and vesical plexiform neurofibromas in a patient with neurofibromatosis type 1: a case report.

BACKGROUND: Neurofibromatosis type 1 is a neurocutaneous genetic disorder caused by mutations in the NF1 gene, resulting in the formation of benign tumors called neurofibromas. The most common type of tumor seen in patients with neurofibromatosis type 1 is the slow-growing and benign neurofibroma, with a subtype called plexiform neurofibroma being particularly common and causing pain, functional impairment, and cosmetic disfigurement. CASE PRESENTATION: We report the case of a 20-year-old North African female patient with a history of neurofibromatosis type 1 who presented with a growing mass in her right gluteal region, which was later diagnosed as a giant cutaneous neurofibroma. Imaging studies revealed infiltration in several regions, including the urinary bladder wall, resulting in significant bilateral hydronephrosis. The patient is currently being monitored, and no excisional procedures are planned. CONCLUSIONS: Neurofibromatosis type 1 can cause a variety of clinical symptoms, including the development of large plexiform neurofibromas. It is important to closely monitor patients with neurofibromatosis type 1 for the early detection of neurofibromas. Early detection and prompt surgical intervention are essential for preventing complications.

Neurofibromatosis type 1-associated plexiform neurofibromas of the neck: topography of lesions and surgical treatment data of 69 patients.

PURPOSE: Plexiform neurofibromas (PNF) are rare tumors arising from peripheral nerve sheath cells. PNF are a hallmark in patients with neurofibromatosis type 1 (NF1), a tumor predisposition syndrome. PNF often grow invasively and destructively, what may complicate surgical treatment. Data on frequency, location, and surgical procedures of patients with NF1-associated FPNF are scarce. This study provides treatment data of NF1 patients. METHODS: Localization and treatment data of 69 NF1 patients with neck PNF were analyzed. Frequency of lesions was recorded in coded colors on schematic neck drawings. RESULTS: The tumors showed no side preference, were located in the entire area under investigation, and did not respect anatomical units/dermatomes. However, the sternocleidomastoid region was particularly frequently affected. The mean number of surgical measures per patient was 1.33. Complications were extensive swelling, hematoma, and bleeding. Histological assessment usually confirmed the clinical assessment of neoplasm. However, histologic differentiation of PNST reveals differences in between tumors that have been unified in clinical assessment as PNF. CONCLUSION: The color-coded, schematic overview of the frequency distribution of surgical neck interventions in NF1 patients with PNF proved a useful tool to gain assessment of preferred treatment needs. The imaging procedure may be suitable for controlling the external aspect of natural tumor development (growth, effects of aging) in the same way as the documentation of the post-surgical course. Treatment plans for patients with these tumors should consider that repeated interventions may be necessary to achieve a longer-term stable result.

Association of plexiform and diffuse neurofibromas with malignant peripheral nerve sheath tumor in NF I patients: a whole-body MRI assessment.

OBJECTIVE: The aim of this study is to evaluate neurofibromatosis type 1 (NF1) patients with whole-body MRI (WBMRI) to investigate the frequency of plexiform neurofibromas (pNFs), diffuse neurofibromas (dNFs), and malignant peripheral nerve sheath tumors (MPNSTs). MATERIALS AND METHODS: In this retrospective cross-sectional study, between the years 2015 and 2023, 83 consecutive patients with known NF1 underwent a total of 110 WBMRI screenings for MPNST using a standardized institutional protocol. The lesions are categorized as discrete lesions, pNFs, dNFs, and MPNSTs. Histopathology served as the reference standard for all MPNSTs. RESULTS: Among the 83 patients analyzed, 53 (64%) were women and 30 were men (36%) of ages 36.94±14.43 years (range, 15-66 years). Of the 83 patients, 33 have a positive family history of NF1 and positive genetic studies. Seven of 83 (8%) have only dNF, 20/83 (24%) have pNF, 28/83 (34%) have both dNF and pNF, and 28/83 (34%) have neither. Of the 83 patients, eight (9.6%) were diagnosed with nine total MPNSTs. Age range for patients with MPNSTs at time of diagnosis was 22-51, with an average age of 33.4 years. Only one MPNST (11%) developed from underlying pNF 4 years after WBMRI along the right bronchial tree. Three of eight (37.5%) patients with MPNST died within 5 years of pathologic diagnosis. CONCLUSION: This study suggests the absence of a predisposition for development of MPNST from pNFs and dNFs in the setting of NF1. As such, these lesions may not need special surveillance compared to discrete peripheral nerve sheath tumors.

A simplified technique for correction of complete ptosis secondary to palpebral neurofibromatosis.

PURPOSE: To present a simplified technique in management of complete ptosis secondary to neurofibromatosis. METHODS: This prospective, non-comparative, clinical interventional study included 13 patients with complete ptosis secondary to histologically proved plexiform neurofibromas. It was conducted at the Orbital Unit of Assiut University Hospital, the referral center of Upper Egypt in the period between June 2013 and October 2021. In all cases, a simplified technique of 5 surgical steps was applied: (A) Division of the involved eyelid surgically into three parts by drawing 2 curvilinear lines, the superior line 11 mm below and parallel to the lower eyebrow hairline and the inferior one 10 mm above the lid margin, (B) Resection (full-thickness) of the large middle part which involves the main pathology and lies between the 2 lines, (C) Preservation of the upper part with identification, dissection and clamping of the levator muscle, (D) Refinement of the lower part by removal of any tissue between the skin and the debulked tarsus and (E) Re-suturing of the upper and lower parts in layers; conjunctiva to conjunctiva, levator to tarsus (after resection of a part that corrects the ptosis) and skin to skin. RESULTS: Ptosis was completely corrected in 8 cases (61.5%) and residual mild ptosis occurred in 5 patients (38.5%). No exposure keratopathy or tumor growth was reported during the follow-up period of minimum 1 year. CONCLUSIONS: This simplified technique could be considered as a surgical basis for correction of complete ptosis in neurofibromatosis.

Recommendations for assessing appearance concerns related to plexiform and cutaneous neurofibromas in neurofibromatosis 1 clinical trials.

BACKGROUND/AIMS: Individuals with neurofibromatosis 1 may experience changes in their appearance due to physical manifestations of the disorders and/or treatment sequelae. Appearance concerns related to these physical changes can lead to psychological distress and poorer quality of life. While many neurofibromatosis 1 clinical trials focus on assessing changes in tumor volume, evaluating patients' perspectives on corresponding changes in symptoms such as physical appearance can be key secondary outcomes. We aimed to determine whether any existing patient-reported outcome measures are appropriate for evaluating changes in appearance concerns within neurofibromatosis 1 clinical trials. METHODS: After updating our previously published systematic review process, we used it to identify and rate existing patient-reported outcome measures related to disfigurement and appearance. Using a systematic literature search and initial triage process, we focused on identifying patient-reported outcome measures that could be used to evaluate changes in appearance concerns in plexiform or cutaneous neurofibroma clinical trials in neurofibromatosis 1. Our revised Patient-Reported Outcome Rating and Acceptance Tool for Endpoints then was used to evaluate each published patient-reported outcome measures in five domains, including (1) respondent characteristics, (2) content validity, (3) scoring format and interpretability, (4) psychometric data, and (5) feasibility. The highest-rated patient-reported outcome measures were then re-reviewed in a side-by-side comparison to generate a final consensus recommendation. RESULTS: Eleven measures assessing appearance concerns were reviewed and rated; no measures were explicitly designed to assess appearance concerns related to neurofibromatosis 1. The FACE-Q Craniofacial Module-Appearance Distress scale was the top-rated measure for potential use in neurofibromatosis 1 clinical trials. Strengths of the measure included that it was rigorously developed, included individuals with neurofibromatosis 1 in the validation sample, was applicable to children and adults, covered item topics deemed important by neurofibromatosis 1 patient representatives, exhibited good psychometric properties, and was feasible for use in neurofibromatosis 1 trials. Limitations included a lack of validation in older adults, no published information regarding sensitivity to change in clinical trials, and limited availability in languages other than English. CONCLUSION: The Response Evaluation in Neurofibromatosis and Schwannomatosis patient-reported outcome working group currently recommends the FACE-Q Craniofacial Module Appearance Distress scale to evaluate patient-reported changes in appearance concerns in clinical trials for neurofibromatosis 1-related plexiform or cutaneous neurofibromas. Additional research is needed to validate this measure in people with neurofibromatosis 1, including older adults and those with tumors in various body locations, and explore the effects of nontumor manifestations on appearance concerns in people with neurofibromatosis 1 and schwannomatosis.

Mandibular symmetry on posterior-anterior cephalograms of neurofibromatosis type 1 patients with facial plexiform neurofibroma.

Introduction: Neurofibromatosis type 1 (NF1) is an is an autosomal dominant heritable tumor predisposition syndrome.. Peripheral nerve sheath tumors (PNST) are a hallmark of NF1. Plexiform neurofibromas (PNF) are neoplasms that are characteristic of NF1, often causing disfiguring effects (e.g., on the face), and are considered precancerous lesions. Previous studies have shown that facial PNF (FPNF) have an impact on the shape of facial bones. This study examines deviations of mandibular symmetry from cephalometric reference planes considering the topography of FPNF. Material and methods: The posterior-anterior (PA) cephalograms of 168 patients with NF1 were examined. We compared three groups: patients with FPNF (n=74), with disseminated cutaneous neurofibroma (DNF (n=94)), and control subjects without NF1 (n=23). The PNF group was subtyped with respect to facial PNST type and location. Typical mandibular cephalometric reference points were determined (condyle, antegonion, and menton). Results: The skeletal measurement points of the mandible in FPNF patients often differ significantly from those of the DNF group. It has been proven that typical asymmetries of the median-sagittal measurement points are indicators of PNF. Differences within the trigeminal tumor spread patterns are indicated in the measured values. A local tumor effect (PNF) on the relation of the measurement points to the reference planes is made plausible by the study results. The investigations prove that tumor type (FPNF) and the number of FPNF affected branches of the trigeminal nerve may correlate with significant deviations of mandible from symmetry on PA projections. Conclusion: The presented study shows that characteristic patterns of mandibular deformity can be measured on standardized radiographs in NF1 patients with FPNF. Mandibular deformities imaged on standardized radiographs may be initial indicators of a previously unrecognized NF1. Tumor-associated alterations of the mandible should be considered in the classification systems of pathognomonic, diagnostically pioneering osseous findings in NF1. The radiological findings provide clues for planning mandibular osteotomies in NF1 patients, especially for assessing facial regions typically highly vascularized by tumor spread. Furthermore, the radiological findings are an indication of a tumor potentially invading and destroying adjacent masticatory and mimic muscle, findings that may have an influence on surgical measures (function, aesthetics, and wound healing).

Plexiform Schwannoma of Digital Nerve.

Plexiform schwannoma is an uncommon benign tumour that grows in a plexiform pattern. We report a 47-year-old man with a mass on the palmar aspect of the metacarpophalangeal joint of the right index finger that had been growing gradually for more than 10 years. The mass was palpated from the distal carpal tunnel to the ulnar aspect of the proximal interphalangeal joint of the index finger, with tingling and numbness sensation. The tumour was a multinodular tumour involving the first common palmar digital nerve to the ulnar proper palmar digital nerve. It was resected and reconstructed with a sural nerve graft. Plexiform schwannoma is rare in the digital nerve, with only six cases reported. Generally, classic schwannomas can be enucleated without causing neurologic deficits; however, plexiform schwannoma may require nerve resection. There have been reports of recurrence of plexiform schwannoma; definitive resection and long-term follow-up are necessary. Level of Evidence: Level V (Therapeutic).

Management of Central and Peripheral Nervous System Tumors in Patients with Neurofibromatosis.

Neurofibromatosis type I (NF1), neurofibromatosis type 2 (NF2), and schwannomatosis represent a diverse group of genetic tumor predisposition syndromes with a shared feature of tumors affecting the peripheral nerve sheaths. PURPOSE OF REVIEW: Many advancements have been made in understanding the biologic underpinnings of these conditions, and in 2016 the first drug was approved by the FDA to treat pediatric symptomatic unresectable plexiform neurofibromas. RECENT FINDINGS: Mek inhibitors have provided a much-needed therapeutic avenue for NF1 patients with unresectable plexiform neurofibromas (PN), both for reduction of tumor bulk and for improvement in symptoms. Selumetinib is the first FDA approved drug for PN, but is only approved for children. Some research suggests that alternative Mek inhibitors and other mixed tyrosine kinase inhibitors may have better efficacy in adults. Vascular endothelial growth factor (VEGF) inhibitor bevacizumab can prolong hearing and delay the need for surgery in NF2 patients with bilateral vestibular schwannomas. This article provides an update regarding considerations and approaches when treating the tumors associated with the neurofibromatoses (NF), including risk and prognosis metrics, clinical trial results, surgical techniques, and radiation therapy recommendations.

Development and pilot validation of a novel disfigurement severity scale for plexiform neurofibromas in children with neurofibromatosis type 1.

BACKGROUND/AIMS: We developed an observer disfigurement severity scale for neurofibroma-related plexiform neurofibromas to assess change in plexiform neurofibroma-related disfigurement and evaluated its feasibility, reliability, and validity. METHODS: Twenty-eight raters, divided into four cohorts based on neurofibromatosis type 1 familiarity and clinical experience, were shown photographs of children in a clinical trial (NCT01362803) at baseline and 1 year on selumetinib treatment for plexiform neurofibromas (n = 20) and of untreated participants with plexiform neurofibromas (n = 4). Raters, blinded to treatment and timepoint, completed the 0-10 disfigurement severity score for plexiform neurofibroma on each image (0 = not at all disfigured, 10 = very disfigured). Raters evaluated the ease of completing the scale, and a subset repeated the procedure to assess intra-rater reliability. RESULTS: Mean baseline disfigurement severity score for plexiform neurofibroma ratings were similar for the selumetinib group (6.23) and controls (6.38). Mean paired differences between pre- and on-treatment ratings was -1.01 (less disfigurement) in the selumetinib group and 0.09 in the control (p = 0.005). For the disfigurement severity score for plexiform neurofibroma ratings, there was moderate-to-substantial agreement within rater cohorts (weighted kappa range = 0.46-0.66) and agreement between scores of the same raters at repeat sessions (p > 0.05). In the selumetinib group, change in disfigurement severity score for plexiform neurofibroma ratings was moderately correlated with change in plexiform neurofibroma volume with treatment (r = 0.60). CONCLUSION: This study demonstrates that our observer-rated disfigurement severity score for plexiform neurofibroma was feasible, reliable, and documented improvement in disfigurement in participants with plexiform neurofibroma shrinkage. Prospective studies in larger samples are needed to validate this scale further.