Perineurioma (PN) is an uncommon benign tumor originating from the peripheral nerve sheath and composed solely of perineurial cells. Most PNs occur sporadically and are typically described as painless masses. This report presents an atypical case of extraneural or soft tissue PN (ESTP) in a 37-year-old Filipino female with a history of trauma. The patient presented with a 5-month history of a gradually enlarging nodule on her right thumb accompanied by localized dull pain. Physical examination revealed the presence of an ill-defined, slightly erythematous, firm, movable, and tender nodule. Histopathological analysis demonstrated characteristic features of ESTP, including spindled cells arranged in a whorled pattern. Immunohistochemical staining for epithelial membrane antigen was positive, while S-100 staining was negative, which confirmed the diagnosis. The nodule was successfully excised without any complication. There was no recurrence observed during the 4thmonth postexcision. This case highlights the importance of considering ESTP as a potential diagnosis for painful masses following trauma and suggests a possible association between ESTP and trauma. Surgical excision remains the preferred treatment option for ESTP, and recurrences are infrequent.

Human ; Female ; Adolescent: 13-18 Yrs Old ; Nerve Sheath Neoplasms ; Peripheral Nerves ; Neoplasms

Malignant peripheral nerve sheath tumor (MPNST) is a rare neurogenic malignant tumor. MPNST has aty-pical clinical symptoms and imaging presentations, difficult diagnosis, a high degree of malignancy, and poor prognosis. It usually occurs in the trunk, approximately 20% in the head and neck, and rarely in the mouth. This paper reports a case of MPNST of the tongue. A summary of the clinical features, diagnosis, and treatment of MPNST is presented in combination with a literature review to provide a reference for the diagnosis and treatment of this disease.
Humans ; Nerve Sheath Neoplasms/pathology* ; Neurofibrosarcoma ; Tongue/pathology*

Objective: To investigate the clinicopathological, immunophenotypic, and genetic features of malignant peripheral nerve sheath tumor (MPNST). Methods: Twenty-three cases of MPNST were diagnosed at the Jiangsu Province Hospital (the First Affiliated Hospital of Nanjing Medical University), China, between January 2012 and December 2022 and thus included in the study. EnVision immunostaining and next-generation sequencing (NGS) were used to examine their immunophenotypical characteristics and genomic aberrations, respectively. Results: There were 10 males and 13 females, with an age range of 11 to 79 years (median 36 years), including 14 cases of neurofibromatosis type I-associated MPNST and 9 cases of sporadic MPNST. The tumors were located in extremities (7 cases), trunk (4 cases), neck and shoulder (3 cases), chest cavity (3 cases), paraspinal area (2 cases), abdominal cavity (2 cases), retroperitoneum (1 case), and pelvic cavity (1 case). Morphologically, the tumors were composed of dense spindle cells arranged in fascicles. Periphery neurofibroma-like pattern was found in 73.9% (17/23) of the cases. Under low magnification, alternating hypercellular and hypocellular areas resembled marbled appearance. Under high power, the tumor cell nuclei were irregular, presenting with oval, conical, comma-like, bullet-like or wavy contour. In 7 cases, the tumor cells demonstrated marked cytological pleomorphism and rare giant tumor cells. The mitotic figures were commonly not less than 3/10 HPF, and geographic necrosis was often noted. Immunohistochemically, tumor cells were positive for S-100 (14/23, 60.9%) and SOX10 (11/23, 47.8%). The loss of the CD34-positive fibroblastic network encountered in neurofibromas was observed in 14/17 of the MPNST cases. The loss of H3K27me3 expression was observed in 82.6% (19/23) of the cases. Moreover, SDHA and SDHB losses were presented in one case. NGS revealed that NF1 gene loss of function (germline or somatic) were found in all 5 cases tested. Furthermore, four cases accompanied with somatic mutations of SUZ12 gene and half of them had somatic mutations of TP53 gene, while one case with germline mutation in SDHA gene and somatic mutations in FAT1, BRAF, and KRAS genes. Available clinical follow-up was obtained in 19 cases and ranged from 1 to 67 months. Four patients died of the disease, all of whom had the clinical history of neurofibromatosis type Ⅰ. Conclusions: MPNST is difficult to be differentiated from a variety of spindle cell tumors due to its wide spectrum of histological morphology and complex genetic changes. H3K27me3 is a useful diagnostic marker, while the loss of CD34 positive fibroblastic network can also be a diagnostic feature of MPNST. NF1 gene inactivation mutations and complete loss of PRC2 activity are the common molecular diagnostic features, but other less commonly recurred genomic aberrations might also contribute to the MPNST pathogenesis.
Female ; Male ; Humans ; Child ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged ; Neurofibrosarcoma ; Neurofibromatosis 1 ; Histones ; Genes, p53 ; Nerve Sheath Neoplasms

Malignant peripheral nerve sheath tumor (MPNST) is rare, accounting for 5-10% of all soft tissue sarcomas. MPNST is characteristically aggressive and has a poor prognosis. Fifty percent of patients with MPNST have neurofibromatosis type 1 (NF1). NF-associated MPNST occurs more often at younger ages than sporadic MPNST, but the survival difference is controversial. Superficial MPNST from a recurrent neurofibroma is extremely rare and only a limited number of cases have been reported in the literature. Herein, we report an unusual case of superficial MPNST from a recurrent neurofibroma in a patient without NF1.
Abdominal Wall ; Humans ; Nerve Sheath Neoplasms ; Neurilemmoma ; Neurofibroma ; Neurofibromatoses ; Neurofibromatosis 1 ; Neurofibrosarcoma ; Peripheral Nerves ; Prognosis ; Sarcoma

Schwannoma or neurilemmoma is a benign peripheral nerve sheath tumor that arises from Schwann cells. Approximately 25–45% of all schwannomas occur in the head and neck regions, and the intraoral presentation of these is only 1%. We report a rare case of a patient presenting tongue base schwannoma with characteristic imaging features on computed tomography and magnetic resonance imaging.
Diagnosis, Differential ; Head ; Humans ; Magnetic Resonance Imaging ; Neck ; Nerve Sheath Neoplasms ; Neurilemmoma ; Peripheral Nerves ; Schwann Cells ; Tongue

Schwannomas are neurogenic tumors, which are among the most varied tumors with respect to morphology, clinical associations, and presentations; they occur in a wide variety of sites. The uterine cervix is a rare site of occurrence and only 15 cases of schwannomas of the uterine cervix, including 5 benign and 10 malignant cases, have been reported to date. Thus, schwannomas of the uterine cervix may pose diagnostic difficulty. Here, we report a case of benign schwannoma of the uterine cervix in a 37-year-old female, who presented with vaginal spotting.
Adult ; Cervix Uteri ; Female ; Humans ; Metrorrhagia ; Nerve Sheath Neoplasms ; Neurilemmoma ; Polyps ; Schwann Cells

Biopsy ; Humans ; Male ; Middle Aged ; Muscle Neoplasms ; diagnosis ; pathology ; Neoplasm Metastasis ; Nerve Sheath Neoplasms ; diagnosis ; pathology ; Recurrence ; Sciatic Nerve ; pathology ; Tomography, X-Ray Computed

OBJECTIVE: Because the anatomical structure of the brachial plexus is very complex, surgical treatment of tumors in this region is challenging. Therefore, a lot of clinical and surgical experience is required for successful treatment; however, many neurosurgeons have difficulty accumulating this experience owing to the rarity of brachial plexus tumors. The purpose of this report is to share our surgical experience with brachial plexus tumor with other neurosurgeons.METHODS: The records of 18 consecutive patients with brachial plexus tumors who underwent surgical treatment between January 2010 and December 2017 in a single institution were retrospectively reviewed. The surgical approach was determined according to the tumor location and size, and intraoperative neurophysiological monitoring (IONM) was used in most of cases to prevent iatrogenic nerve injury during surgery. In addition, to evaluate the differences in tumor characteristics according to pathologic diagnosis, the tumors were divided twice into two groups, based on two separate classifications, and statistical analysis was performed.RESULTS: The 18 brachial plexus tumors comprised 15 (83.3%) benign peripheral nerve sheath tumors including schwannoma and neurofibroma, one (5.6%) malignant peripheral nerve sheath tumor, one (5.6%) benign tumor of non-neural sheath origin (neurogenic cyst), and one (5.6%) metastatic tumor (papillary carcinoma). The authors analyzed relationship between tumor size/location and tumor characteristic parameters such as age, size, right-left, and pathology. There were no statistically significant differences except a tendency of bigger tumor size in young age.CONCLUSION: For a successful surgical outcome, an appropriate surgical approach is essential, and the appropriate surgical approach is determined by the location and size of the tumor. Furthermore, applying IONM may prevent postoperative complications and it is favorable option for brachial plexus tumors surgery.
Brachial Plexus Neuropathies ; Brachial Plexus ; Classification ; Diagnosis ; Humans ; Intraoperative Neurophysiological Monitoring ; Monitoring, Intraoperative ; Nerve Sheath Neoplasms ; Neurilemmoma ; Neurofibroma ; Neurosurgeons ; Pathology ; Peripheral Nerves ; Postoperative Complications ; Retrospective Studies

Schwannomas are benign nerve sheath tumors that are typically located in soft tissue. Occasionally, schwannomas involve osseous structures. These intraosseous schwannomas are generally benign neoplasms that account for less than 0.2% of primary bone tumors. Schwannomas are very rarely observed in long bones. We present a case of a schwannoma affecting the proximal femur with a coincident subchondral fracture of the femoral head. A 38-year-old-male presented with left hip pain without deteriorating locomotor function. Plain film radiographs displayed a lobulating contoured lesion within the intertrochanteric portion of the femur. The magnetic resonance imaging (MRI) scans showed a tumor occupying the intertrochanteric region. Diffuse bone marrow edema, especially in the subchondral and head portions of the femur that was possibly due to the subchondral insufficiency fracture was also noted. The lesion was surgically excised and bone grafting was performed. Histologically, there was diffuse infiltrative growth of the elongated, wavy, and tapered cells with collagen fibers, which are findings that are characteristic of intraosseous schwannoma. Although very rare, intraosseous schwannoma should be included in the differential diagnosis of radiographically benign-appearing, non-aggressive lesions arising in the femur. The concomitant subchondral fracture of the femoral head confounded the correct diagnosis of intraosseous schwannoma in this case.
Bone Marrow ; Bone Transplantation ; Collagen ; Diagnosis ; Diagnosis, Differential ; Edema ; Femur ; Fractures, Stress ; Head* ; Hip ; Magnetic Resonance Imaging ; Nerve Sheath Neoplasms ; Neurilemmoma*