Raman difference spectroscopy and U-Net convolutional neural network for molecular analysis of cutaneous neurofibroma.

In Neurofibromatosis type 1 (NF1), peripheral nerve sheaths tumors are common, with cutaneous neurofibromas resulting in significant aesthetic, painful and functional problems requiring surgical removal. To date, determination of adequate surgical resection margins-complete tumor removal while attempting to preserve viable tissue-remains largely subjective. Thus, residual tumor extension beyond surgical margins or recurrence of the disease may frequently be observed. Here, we introduce Shifted-Excitation Raman Spectroscopy in combination with deep neural networks for the future perspective of objective, real-time diagnosis, and guided surgical ablation. The obtained results are validated through established histological methods. In this study, we evaluated the discrimination between cutaneous neurofibroma (n = 9) and adjacent physiological tissues (n = 25) in 34 surgical pathological specimens ex vivo at a total of 82 distinct measurement loci. Based on a convolutional neural network (U-Net), the mean raw Raman spectra (n = 8,200) were processed and refined, and afterwards the spectral peaks were assigned to their respective molecular origin. Principal component and linear discriminant analysis was used to discriminate cutaneous neurofibromas from physiological tissues with a sensitivity of 100%, specificity of 97.3%, and overall classification accuracy of 97.6%. The results enable the presented optical, non-invasive technique in combination with artificial intelligence as a promising candidate to ameliorate both, diagnosis and treatment of patients affected by cutaneous neurofibroma and NF1.

Myxoid neurofibroma masquerading as lymphatic-venous malformation and poses a diagnostic challenge on fine needle aspiration biopsy.

BACKGROUND: Myxoid neurofibromas (NF) are uncommon, benign spindle cell tumors that originate from peripheral nerve sheaths, often posing a diagnostic challenge due to their hypocellularity on cytology specimens. Distinguishing myxoid spindle cell lesions can be challenging, given the broad range of potential differential diagnoses. CASE PRESENTATION: A 26-year-old female with a past medical history of embolized inguinal, flank, and retroperitoneal venolymphatic malformation presented with a left pelvic pain causing significant disability. CT scan showed an extensive 8.7 cm × 6.6 cm retroperitoneal mass. FNA was performed and alcohol-fixed papanicolaou-stained smears showed a hypocellular specimen with loosely arranged clusters of bland spindle cell proliferation in the background of a mucoid matrix. Spindle cells showed scant cytoplasm and elongated oval-shaped regular nuclei. Prominent nucleoli were not seen. An excisional biopsy revealed a bland spindle cell proliferation in a myxoid background associated with shredded collagen bundles. Immunohistochemical staining showed diffuse positivity for S100 and CD34. Based on the overall findings, a definitive diagnosis of myxoid neurofibroma was rendered. DISCUSSION: Cytological features of myxoid neurofibroma include the presence of hypocellular spindle-shaped cells arranged in small, loosely organized groups within a myxoid matrix background. Cells exhibit scant cytoplasm with regular oval and elongated nuclei. Nucleoli are typically not identified. The differential diagnosis includes myxoid neurofibroma, myxoma, myxoid liposarcoma, myxoid chondrosarcoma, myxoid dermatofibrosarcoma protuberans, low-grade fibromyxoid sarcoma, and low-grade myxo-fibrosarcoma. CONCLUSION: We aim to highlight the importance of considering myxoid neurofibroma in the differential diagnosis of hypocellular myxoid spindle cell lesions encountered on fine-needle aspiration cytology.

A Giant Scrotal Neurofibroma in a Child Masquerading as Filariasis: Uncommon Presentation of a Common Disease.

Neurofibroma of the scrotum is a very uncommon benign neoplasm, specifically when it affects teenagers and is not associated with neurofibromatosis type I. To the best of our knowledge, only a couple of cases of neurofibroma in children have been documented. Here, we report a case study of a 17-year-old boy who had a giant scrotal lump for ten years masquerading clinically as filariasis. A provisional diagnosis of benign nerve sheath neoplasm was made based on cytology findings. The lump was surgically removed from the patient, and a histopathological and immunohistochemistry examination established the diagnosis of neurofibroma. The combined clinical, preoperative cytological, histological, and immunohistochemistry findings were not presented in the literature in any of the formerly documented cases of scrotal neurofibroma. The current case expands the spectrum of differential diagnoses for scrotal tumours that clinicians have previously observed.

Neurofibroma: Case Series with Clinical Features and Recommendations.

Neurofibroma is an autosomal benign disorder. It can be localized, diffuse or invasive like plexiform neurofibroma that involves the nerves, muscle, tissues, skeleton. It represents itself as a destructive variant of neurofibroma, mostly present as orbital or periorbital neurofibroma or may be associated with autosomal dominant disease. Clinical diagnosis of neurofibromatosis (NF) according to National Institutes of Health (NIH) criteria should have more than two of the seven features including lisch nodules, cafe'- au-lait spots, plexiform neurofibroma, optic glioma, freckling, first degree relative with NF or dysplasia of cortical bones. However, proper early diagnosis is still crucial due to its various presentation such as cheek mass, painless swelling on skin, chalazion, intratracheal tumor, genital swelling or ptosis. It is reported that neurofibroma often represents as ocular or facial swelling. Here we are presenting features of neurofibroma of eight cases of patients from Civil Hospital, Karachi. These cases had main complain of overhanging skin mass mainly on orbital or periorbital region that damage the area and with poor daily activities. Multiple nodules on face and body along with them Cafe'-au-lait spots and lisch nodules were main signs. While, other signs i.e. ptosis, pterygium, telecanthus and muddy discoloration of conjunctiva need further evaluation for correlation with neurofibromatosis. Debulking surgery was planned for most of the cases but the huge disfigurement caused by overhanging skin mass and nodules made it a challenge for plastic surgeons to provide good outcomes with minimum damage. Keywords: neurofibroma; lisch nodules; ptosis; Cafe'-au-lait spot; periorbital; overhanging skin.

Intratemporal facial nerve neurofibroma causing facial paralysis in an infant: Case report and review of the literature.

This article describes the first recorded case of intratemporal neurofibroma in an infant. A literature review of all other existing cases of intratemporal neurofibroma is performed, finding that the majority of cases involve multiple segments and can be found in the mastoid segment most often. Most common symptoms described included facial paralysis, otalgia, and conductive hearing loss, respectively.

[Application of peroral endoscopic-assisted laryngeal microsurgery in children with laryngeal neurofibromas].

Objective:To investigate the clinical manifestations and the effect of peroral endoscopic-assisted laryngeal microsurgery for children with laryngeal neurofibroma, and to provide clinical reference for the diagnosis and treatment of this disease. Methods:The clinical data of 4 children with laryngeal tumors admitted to the Department of Otorhinolaryngology, Children's Hospital of Chongqing Medical University from January 2021 to June 2023 were retrospectively analyzed. Laryngeal tumors were removed by peroral endoscopic-assisted laryngeal microsurgery. One case underwent tracheotomy at the same time, and one case was simultaneously performed with laryngeal T tube placement and tracheotomy. Results:Surgical resection is the best treatment for laryngeal neurofibroma, and laryngeal microsurgery should be actively used for patients with surgical indications.This surgical method has the advantages of good efficacy, minimal invasion, aesthetics and preservation of laryngeal function, which not only ensures safety, but also improves the quality of life after surgery, and has the value of development and promotion.

Subcutaneous Nasal Schwannoma in a Pediatric Patient: A Rare Case Report with Emphasis on Histopathology's Role in Differential Diagnosis.

BACKGROUND Schwannomas are rare and benign tumors of the nerve sheath, composed of Schwann cells, and they are extremely rare in the nasal area. Here, we report a case that presented to our clinic as a growing nasal mass and was found to be a unilateral subcutaneous schwannoma. There have been a few previous cases reported of such patients having nasal obstruction, epistaxis, or other symptoms, but our patient did not. We stress the importance of considering schwannoma in the differential diagnosis of nasal masses, even in pediatric patients, and the role of histopathology differentiating it from other diagnoses such as neurofibroma. CASE REPORT Our patient was a 9-year-old girl with a painless nasal swelling on the nasal bridge that she first noticed 2 years ago, which started growing gradually and began to become firm. She was otherwise asymptomatic and had no relevant family history. Histopathology revealed an encapsulated spindle cell tumor with both hypo- and hyper-cellular areas, and immunohistochemistry showed that the tumor was strongly positive for S-100 and negative for both desmin and CD34, with blood vessels marking. A final diagnosis of schwannoma was made. CONCLUSIONS We presented a case of nasal septal schwannoma, emphasizing the importance of considering schwannoma in the differential diagnosis of nasal masses, and the role of histopathology to rule out other possible diagnoses.

Imaging in gynecological disease (26): clinical and ultrasound characteristics of benign retroperitoneal pelvic peripheral-nerve-sheath tumors.

OBJECTIVE: To describe the clinical and sonographic characteristics of benign, retroperitoneal, pelvic peripheral-nerve-sheath tumors (PNSTs). METHODS: This was a retrospective study of patients with a benign, retroperitoneal, pelvic PNST who had undergone preoperative ultrasound examination at a single gynecologic oncology center between 1 January 2018 and 31 August 2022. All ultrasound images, videoclips and final histological specimens of benign PNSTs were reviewed side-by-side in order to: describe the ultrasound appearance of the tumors, using the terminology of the International Ovarian Tumor Analysis (IOTA), Morphological Uterus Sonographic Assessment (MUSA) and Vulvar International Tumor Analysis (VITA) groups, following a predefined ultrasound assessment form; describe their origin in relation to nerves and pelvic anatomy; and assess the association between their ultrasound features and histotopography. A review of the literature reporting benign, retroperitoneal, pelvic PNSTs with preoperative ultrasound examination was performed. RESULTS: Five women (mean age, 53 years) with a benign, retroperitoneal, pelvic PNST were identified, four with a schwannoma and one with a neurofibroma, of which all were sporadic and solitary. All patients had good-quality ultrasound images and videoclips and final biopsy of surgically excised tumors, except one patient managed conservatively who had only a core needle biopsy. In all cases, the findings were incidental. The five PNSTs ranged in maximum diameter from 31 to 50 mm. All five PNSTs were solid, moderately vascular tumors, with non-uniform echogenicity, well-circumscribed by hyperechogenic epineurium and with no acoustic shadowing. Most of the masses were round (n = 4 (80%)), and contained small, irregular, anechoic, cystic areas (n = 3 (60%)) and hyperechogenic foci (n = 5 (100%)). In the woman with a schwannoma in whom surgery was not performed, follow-up over a 3-year period showed minimal growth (1.5 mm/year) of the mass. We also summarize the findings of 47 cases of benign retroperitoneal schwannoma and neurofibroma identified in a literature search. CONCLUSIONS: On ultrasound examination, no imaging characteristics differentiate reliably between benign schwannomas and neurofibromas. Moreover, benign PNSTs show some similar features to malignant retroperitoneal tumors. They are solid lesions with intralesional blood vessels and show degenerative changes such as cystic areas and hyperechogenic foci. Therefore, ultrasound-guided biopsy may play a pivotal role in their diagnosis. If confirmed to be benign PNSTs, these tumors can be managed conservatively, with ultrasound surveillance. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Extracranial hypoglossal neurofibroma with a variant ansa cervicalis: a case report.

PURPOSE: This case report aims to explore a rare combination of findings in a cadaver donor: variant ansa cervicalis, vagus (CN X) and hypoglossal (CN XII) nerve fusion, and extracranial hypoglossal neurofibroma. BACKGROUND: The type of ansa cervicalis variation presented in this report has been documented in less than 1% of described cases. The CN X-CN XII fusion has been reported in one prior study. Additionally, hypoglossal neurofibromas are benign neoplasms of the peripheral nerve sheath. There are only two known cases of extracranial hypoglossal neurofibroma described in the literature. CASE REPORT: The study investigated a swelling of the right CN XII in a 90-year-old female cadaver donor. Detailed dissection, examination of the region, and histopathological analysis of the mass followed. The entire course of CN XII and other cranial nerves were examined to exclude concurrent pathology. A fusiform enlargement of the right CN XII was observed in the submandibular region, measuring ~ 1.27 × 1.27 cm. The superior portion of the right CN XII was fused to the right CN X, exiting the jugular foramen. The superior root of ansa cervicalis, normally a branch of CN XII, was found to arise from CN X on the right side. The left CN XII and CN X were unremarkable. Histopathological examination revealed benign neurofibroma. CONCLUSION: The anatomical variation and rare location of the tumor necessitate further investigation to better understand pathogenesis, clinical correlation, and surgical implications. This study furthers knowledge of this condition and contributes to the currently limited body of research.

Diagnostic Significance of Ki67 Staining Pattern in Benign Peripheral Nerve Sheath Tumors: An Additional Diagnostic Tool.

Introduction. Benign peripheral nerve sheath tumors involve mainly neurofibromas, schwannomas, and their variants. Ki67 is a widely used immunohistochemical marker that predicts the proliferation rate of tumors including the nerve sheath-derived neoplasms and it is helpful to differentiate them from their malignant counterparts. However, Ki67 score is not used in distinction of the benign peripheral nerve sheath tumors types from each other. Our aim is to contribute to the literature by identifying the hypothesized specific Ki67 staining patterns of benign peripheral nerve sheath tumors. Methods. Fifty-three tumors (distributed as follows: 26 schwannomas, 24 neurofibromas, and 3 hybrid schwannoma-neurofibroma tumors) from 49 patients were included in the study. Two researchers analyzed the slides independently. Tumors were classified according to their Ki67 staining patterns in 3 different groups: zonal (Z-Ki67), focal zonal or mixed (M-Ki67), and scattered Ki67 (S-Ki67). Results. There was a significant correlation among the types of benign peripheral nerve sheath tumor and the Ki67 staining patterns (P < .01). Level of inter-rater reliability was calculated as good (>0.7) and excellent (>0.8) according to 2 different calculations of kappa score. Conclusions. In conclusion, our study demonstrates that the Ki67 staining pattern may be used as an additional diagnostic tool in the diagnosis of benign peripheral nerve sheath tumors.

Hybrid Neurofibroma/Schwannoma of the Oral Cavity: A Rare Case Report and Literature Review.

Hybrid peripheral nerve sheath tumors show combined features of more than one type of conventional benign peripheral nerve sheath tumors. There are few cases reported of hybrid peripheral nerve sheath tumors in the head and neck region. A 68-year-old female patient was referred for evaluation of an oral swelling lasting five years. Intraoral examination revealed a small mobile nodule located in the lower vestibule. The patient underwent excisional biopsy and microscopic evaluation showed typical features of neurofibroma enclosing areas with palisading nuclei compatible with Antoni A pattern, which are seen in schwannomas. These regions showed strong and diffuse immunoreactivity for S100 protein and moderate positivity in the neurofibroma area. CD34 was positive in the neurofibroma area and entrapped axons were positive for neurofilament. The final diagnosis was oral hybrid neurofibroma-schwannoma tumor. Hybrid peripheral nerve sheath tumors, although extremely rare, may arise within the oral cavity. To the best of our knowledge, this is the first neurofibroma-schwannoma tumor reported in the oral cavity. Recognizing hybrid peripheral nerve sheath tumors as a distinct clinicopathological entity is important because they may also be associated with syndromic disorders.

Intraoral neurofibroma: A case report with emphasis on immunohistochemical markers.

ABSTRACT: A neurofibroma is a benign peripheral nerve sheath tumor. They occur in combination with neurofibromatosis or as a solitary mass. Intraoral neurofibromas pose diagnostic difficulties, suggesting the appropriate use of diagnostic markers and clinical knowledge. Here, we report a case of intraoral neurofibroma in a 57-year-old female who reported with the complaint of painless growth in the lower left back tooth region for the past three years. Based on the clinical features, provisional diagnosis of traumatic fibroma was made. However, histopathology proved it to be a benign spindle cell lesion; upon further investigation by immunohistochemistry, it was diagnosed to be a case of neurofibroma.

Benign Neurogenic Tumors.

Neurogenic tumors arise from cells of the nervous system. These tumors can be found anywhere along the distribution of the sympathetic and parasympathetic nervous system and are categorized based on cell of origin: ganglion cell, paraganglion cell, and nerve sheath cells. Ganglion cell-derived tumors include neuroblastomas, ganglioneuroblastomas, and ganglioneuromas. Paraganglion cell-derived tumors include paragangliomas and pheochromocytomas. Nerve sheath cell-derived tumors include schwannomas (neurilemmomas), neurofibromas, and neurofibromatosis. Most of these are benign; however, they can cause local compressive symptoms. Surgery is the mainstay of treatment, if clinically indicated. Nonetheless, a thorough preoperative workup is essential, especially for catecholamine-secreting tumors.

Diagnostic utility of PRAME, p53 and 5-hmC immunostaining for distinguishing melanomas from naevi, neurofibromas, scars and other histological mimics.

High expression of PRAME (PReferentially expressed Antigen in MElanoma) and p53 (a proposed marker of desmoplastic melanoma) and low expression of 5-hydroxymethylcytosine (5-hmC) have each been reported in melanoma. However, their combined diagnostic utility for distinguishing melanomas, including uncommon variants, from histological mimics is unknown. This study sought to determine the utility of PRAME, p53 and 5-hmC immunostains for diagnosing melanocytic tumours. A total of 333 cutaneous melanocytic tumours (melanoma n=280, naevi n=53), 20 cutaneous neurofibromas, and 15 scars were evaluated using multiplex immunofluorescence (n=313) or single-plex chromogenic immunohistochemical staining (n=55). Immunostaining for PRAME and 5-hmC were each scored using a previously described semiquantitative scale 0 (absent) to 4+ (diffuse). p53 was scored using a previously described immunoreactive score (range 0-300). PRAME expression was significantly higher in melanomas than in naevi (p<0.0001), with the lowest PRAME expression found in low-grade desmoplastic melanomas compared to the other melanoma subtypes. In non-desmoplastic melanomas, 38% showed 4+ staining (>75% positive tumour cells) and 70% showed 3+ or 4+(>50% positive tumour cells). Conversely, 96% of naevi showed 0, 1+ or 2+ expression. 5-hmC expression was significantly lower in melanomas than in naevi (p<0.0001). However, acral melanomas were not significantly associated with loss of 5-hmC expression (p=0.84). Compared with using PRAME in isolation, combining PRAME and 5-hmC scores increased sensitivity (64%-84%) for detecting melanoma. With respect to desmoplastic melanoma compared to scar or neurofibroma, strong PRAME or p53 staining were almost exclusively found in high-grade desmoplastic melanomas; low-grade desmoplastic melanomas, neurofibromas and scars were negative. 5-hmC was not useful in distinguishing desmoplastic melanomas from neurofibromas or scars. Our data support the use of PRAME as a highly specific ancillary investigation in the diagnosis of melanoma, however PRAME should be considered 'positive' if there is 3+ or 4+ staining (rather than the widely recommended 4+ threshold). 5-hmC, PRAME and p53 appear to have a limited role in the diagnosis of low-grade desmoplastic melanomas.

A case report of a 4-year-old girl with neurofibromatosis type 1.

Neurofibromatosis type 1 is a rare genetic disorder, which is a benign nerve tumor resulting from aberrant growth of the cells of nerve sheath. NF1 patients were associated with multisystem involvement, characterized by neurofibroma, of which 50% were associated with plexus neurofibroma. Characteristically benign plexiform neurofibromas can cause pain, disfigurement, compression and functional changes. Although plexiform neurofibroma is common in the head and neck, the orbital plexiform neurofibroma is rare and easily confused with other orbital tumors. There is no consensus with regard to the treatment strategy of plexiform neurofibromas, current treatment has remained largely surgical, but comes with a high recurrence rate after partial removal. We describe a case of a 4-year-old patient with orbital plexiform neurofibroma who has a 3-year history of ptosis in the right eye. At the begining, we misdiagnosed it as hemangioma. After surgical resection, it was confirmed as plexiform neurofibroma by histopathological examination. One year after surgery, the tumor recurred, so surgical resection was performed again, and the ptosis was corrected. After that, the patients were followed up and examined annually, and no recurrence was found so far. This case shows that an infant or a child present with unilateral eye swelling and ptosis of the upper eyelid should be evaluated for orbital neurofibroma.

How to Distinguish Solitary Neurofibroma From Neurofibromatosis Type 1.

ABSTRACT: Neurofibroma is a benign tumor originating from Schwann cells. It is diagnosed as a symptom of neurofibromatosis type 1 (NF1) or solitary neurofibroma. Neurofibromatosis type 1 belongs to a class of hereditary diseases, whereas solitary neurofibroma is not. Presence of germline NF1 gene mutations can be used to distinguish the 2 conditions. However, due to false negative results in gene tests, NF1 may be misdiagnosed as solitary neurofibroma. This calls for development of more accurate diagnostic methods. The authors report 2 patients with neurofibroma who required surgery and fertility consulting. using primary cell culture and next-generation sequencing experiments, the authors found NF1 mutation in neurofibroma Schwann cells. But this mutation was not exit in peripheral blood, hence demonstrate this NF1 mutation was somatic rather than germline. These results confirmed the diagnosis of solitary neurofibroma rather than NF1. The presented method is, therefore, suitable for fertility consultation and diagnosis of solitary neurofibroma patient.