Peripheral Nerve Sheath Tumor: A Diagnostic and Therapeutic Challenge.

INTRODUCTION: Peripheral nerve tumors are a group of rare soft tissue tumors of neuro-ectodermal origin. Although the majority of them are benign in nature, up to 10% can be malignant. The symptoms depend on the site, size, and structures compressed by the tumor. AIM: To highlight the heterogeneity of signs and symptoms and their presentations, which has often made it difficult for the attending physician to accurately diagnose and direct the patient toward appropriate treatment. METHODS: Eight patients treated at our tertiary care hospital between 2015 and 2022 were included in this study. They were evaluated in detail. Treatment was surgical. The patients underwent complete excision of the tumor under magnification to help preserve the adjacent neurovascular bundle. All patients were followed up post-operatively to document the status of their symptoms. RESULTS: The average duration prior to referral to our hospital was 13 months. Seven subjects had pain at presentation, one had neurological deficit. Seven also complained of swelling. Five of the eight lesions were schwannoma, two neurofibroma and one showed malignant histology. Post-operatively, Hoffman Tinel signs improved in all six subjects. five of the seven subjects were completely pain-free, and the other two had a reduction in symptoms. CONCLUSIONS: Early diagnosis and referral to a specialist center are needed to achieve satisfactory outcomes while treating peripheral nerve tumors. Proliferative lesions should be treated surgically in specialist centers by experienced doctors with appropriate skills and equipment for microsurgical procedures to ensure full recovery.

A Curious Case of Common Peroneal Nerve Schwannoma.

Schwannoma or neurilemmoma is a slow-growing tumor that develops from nerve sheaths. It is mostly benign and only rarely transforms into malignancy. The incidence of schwannoma is very low in the lower limbs. Schwannomas developing from the common peroneal nerve is unlikely. A middle-aged male presented with complaints of left knee pain, which was radiating to the left foot, and a painful swelling at the back of the knee. An intralesional excision was done, and the patient made a full recovery with no postoperative complications. The excised specimen was found to be a schwannoma of the common peroneal nerve of the left leg. At the one-month, three-month, and one-year postoperative follow-ups, the patient had no complaints of pain on passive and active dorsiflexion of the foot. There was complete recovery from paresthesia and intact sensation was present. This report shows that asymptomatic schwannomas can sometimes present with symptoms of pain. In such cases, careful and complete excision of the schwannoma can lead to full recovery.

Gastric Schwannoma-Two Unusual Cases with Usual Presentation and Review of Literature.

Schwannomas, also known as neurilemmomas, are characteristically benign, slow growing neoplasms originating from Schwann cell sheath. Gastrointestinal schwannomas are very rare with stomach being the most affected organ representing approximately 0.2% of all gastric tumours. Malignant transformation is rarely reported in these tumors and complete surgical resection with negative margins is the recommended treatment. Herein, we report our experience of 2 cases of gastric submucosal spindle cell tumour (SMT), which were preoperatively assumed to be as gastrointestinal stromal tumor (GIST), however postoperatively confirmed as schwannoma on immunohistochemical examination.

Schwannoma base of Tongue - Case Report with a Novel Reconstruction Technique.

INTRODUCTION: Schwannomas are benign, slow-growing well-encapsulated neoplasms arising from Schwann cells of nerve sheaths. Oral cavity schwannomas are very rare with an incidence less than 1%. The posterior third of the tongue is not frequently involved. CASE REPORT: We report a rare case of a large tongue base schwannoma in a 44 year old female managed surgically by lateral pharyngotomy approach. A novel reconstruction method involving the use of submental flap is described for the functional reconstruction of the defect. CONCLUSION: Being a rare tumor, schwannoma should not be missed in the differential diagnosis of tongue base tumors. Complete surgical resection is the treatment of choice with recurrence being very rare.

Hybrid peripheral nerve sheath tumours: MRI features with pathological correlation in 24 cases.

OBJECTIVES: To describe the MRI features of histologically proven hybrid peripheral nerve sheath tumours (HPNST). METHODS: A retrospective analysis of the MRI features of 24 histologically proven cases of HPNST over 7 years. Demographic data obtained from clinical records included age, gender, and date of diagnosis. Two readers independently assessed MRI studies and assessed the following features: involvement of a major nerve, intramuscular location, lesion morphology, entering nerve sign, exiting nerve sign, target sign, fascicular sign, split fat sign, and ancient change (cystic change). Inter-observer agreement was assessed with Cohen's kappa coefficient. Histological diagnosis was based on either image-guided needle biopsy or resection histology. RESULTS: The study included 9 males and 15 females with mean age 50 years (range: 24-78 years). Nine tumours (35%) involved a major nerve including spinal roots (5), radial (1), median (1), tibial (1), and axillary (1), while 5 (21%) tumours were intramuscular. The mean tumour size was 4.2 cm (standard deviation of 2.4 cm). The frequency of MRI features was as follows: lobular contour (71%; 17/24), ancient change (38%; 9/24), fascicular sign (17%; 4/24), entering nerve sign (21%; 5/24), exiting nerve sign (13%; 3/24), target sign (13%; 3/24), and split fat sign (8%; 2/24). Inter-observer agreement was high, ranging from 0.7 to 0.83. CONCLUSIONS: HPNST infrequently demonstrate the classical MRI signs of benign peripheral nerve sheath tumours, but commonly have a lobular morphology and can show ancient/cystic change. ADVANCES IN KNOWLEDGE: This is the first study in the literature analysing the MRI features of histologically proven HPNST. HPNST infrequently shows the classical MRI signs that would be expected with benign peripheral nerve sheath tumours although commonly have a lobular morphology and show cystic change.

Nipple Schwannoma: A Case Report and Literature Review on Nipple Mass.

Schwannomas are slow-growing benign tumors originating from the Schwann cells of the peripheral nerve sheaths. Herein, we report the first documented case of a schwannoma presenting as a painful nipple mass in a 32-year-old woman. This mass initially developed six years ago following a period of breastfeeding. Breast magnetic resonance imaging (MRI) scans revealed an iso-intense mass, with an approximate size of 2.2 cm, on a T1-weighted image with internal cystic changes. The mass exhibited heterogeneously delayed enhancement and restricted diffusion. Surgical excision was performed, and the diagnosis of cutaneous plexiform nipple schwannoma was confirmed histopathologically. A literature review revealed that the MRI findings of the nipple mass in our case were consistent with the common features of a schwannoma.

Benign cervical schwannoma with tracheal invasion

ABSTRACT Schwannomas commonly develop in the cervical region, 25% - 45% of cases are diagnosed in this anatomical region. Tracheal neurogenic tumors are exceedingly rare and can be misdiagnosed as invasive thyroid carcinomas or other infiltrating malignancies when present at the level of the thyroid gland. Here, we present a case of synchronous benign cervical schwannoma with tracheal invasion and papillary thyroid carcinoma in a patient who was initially hospitalized for COVID-19. The patient presented with dyspnea that was later found to be caused by tracheal extension of a cervical tumor. Surgical excision was performed, and the surgical team proceeded with segmental tracheal resection, removal of the cervical mass, and total thyroidectomy. The specimen was sent for pathological analysis, which revealed synchronous findings of a benign cervical schwannoma with tracheal invasion and papillary thyroid carcinoma. The literature on this subject, together with the present case report, suggests that neurogenic tumors should be included in the differential diagnosis of obstructing tracheal cervical masses. Surgical excision is the first-line of treatment for benign cervical schwannomas.

Gnathic Schwannomas: A Report of Two Cases and Systematic Review of the Literature.

BACKGROUND: The intraosseous schwannoma (IS) is a benign peripheral nerve sheath tumor postulated to arise de novo or from nerve fibers in preexisting nutrient canals. ISs are uncommon and comprise less than 1% of neoplasms originating in bone. We herein present two cases of mandibular schwannomas-the first case was a 66-year-old female with a four-month history of pain and pressure associated with an anterior mandibular radiolucency, and the second case was an asymptomatic 12-year-old female with separate radiolucencies of her mandibular symphysis and right posterior mandible. Incisional biopsies of all three lesions showed a benign spindle cell neoplasm with histologic features of a schwannoma; the tumor cells were strongly reactive for S-100. The patients underwent complete enucleation of their lesions and are without evidence of disease at ten months and five years, respectively. METHODS: A systematic review was undertaken to evaluate the diagnostic features, treatment, and patient outcomes of gnathic schwannomas. RESULTS: A total of 93 cases were identified with the following demographic findings: predominance in females (57%); average age of occurrence of 37.3 years (8 to 77 years); mean size of 3.6 cm; and involvement of the mandibular body (37.6%), mandibular body and ramus (18.3%), and anterior mandible (18.3%). The predominant clinical sign was swelling (69.9%), and the most common radiographic presentation was a radiolucency (94.6%) with well-defined borders (72%). CONCLUSION: All cases were treated surgically, with an average follow-up interval of 22.9 months and a recurrence rate of 5.4.

Successful management of a giant retroperitoneal ancient schwannoma mimicking malignant tumors: A case report and literature review.

Introduction and Importance: Schwannomas, originating from Schwann cells surrounding nerve sheaths, tend to be slow-growing. Among these, giant ancient schwannomas are remarkable for their rare occurrence and their capacity for substantial growth and regressive changes. Furthermore, the expansiveness and flexibility of the retroperitoneal space often conceal the symptoms of retroperitoneal schwannomas, leading to delayed diagnosis and allowing these tumors to grow significantly and become large and long-standing before detection. Case Presentation: A 24-year-old man presented with left flank pain and a growing abdominal bulge in the left upper quadrant. Computed tomography scan revealed a 15×15×10 cm lytic expansile lesion. Consequently, the encapsulated mass was surgically excised and diagnosed as an ancient retroperitoneal schwannoma through histological and immunohistochemical studies. Clinical Discussion: Comprehensive preoperative planning and a multidisciplinary strategy are imperative for the complete excision of schwannomas. These tumors can present diagnostic complexities, particularly due to nuclear atypia and pleomorphism, which might lead to misinterpretation regarding malignancy. Despite the risks associated with percutaneous biopsies, the low mitotic count is a critical diagnostic factor. Our study underscores the consensus that the definitive diagnosis should rely on postoperative histopathological findings, highlighting the importance of accurate assessment. Conclusion: Rare giant retroperitoneal ancient schwannomas pose diagnostic challenges due to their rarity, lack of distinct symptoms, and atypical locations. This study presents a successful case and management.

A Case of an Uncommon Lower Lip Swelling.

A woman in her fifty-seventh year appeared with a painless swelling on her left lower lip that had been present for three years. The size of the swelling was noticeably increasing in size over time. On examination, there was a lump that was firm, non-tender, and measured 2 cm x 1 cm above the lower lip. The oral cavity, as well as the intraoral mucosa, were normal and unremarkable in appearance. As fine-needle aspiration cytology revealed a spindle cell lesion, she had an excision biopsy performed, followed by bilateral advancement flap closure. Histopathological examination (HPE) revealed a schwannoma in the tissue sample. Schwannomas are rare, benign neural tumors originating from Schwann cells. They are mainly asymptomatic and have a moderate rate of growth. Excision is the recommended treatment for schwannomas. Proper surgical planning and postoperative monitoring are crucial for optimal wound healing and complete recovery.

Painful schwannoma of scalp: A case report.

Schwannoma, also known as neurilemmoma, is a benign neoplasm of Schwann cells of the cranial or peripheral nerve sheath. Scalp involvement has been reported in 25% of patients with extracranial head and neck schwannomas, which can be misdiagnosed clinically as epidermal cyst or lipoma. In this article, we report a 32-year-old male presenting with a slow-growing painful subcutaneous mass on the left occipital scalps without any neurological symptoms. Pathological findings confirmed the diagnosis of schwannoma, and surgical removal resulted in the resolution of pain and lack of recurrence.

Neurilemmoma of Tongue in A Young Female: A Case Report.

Neurilemmomas are benign, slowly growing tumors originating from Schwann cells in peripheral nerves. The precise cause is unclear. They commonly occur in the head and neck region (25-48% of cases) and rarely in the oral cavity (1%). While lingual schwannomas can develop at any age, they are most frequently seen between the ages of 30 and 60 years. In this case, a 19-year-old female was diagnosed with a lingual schwannoma. She had experienced painless swelling along the left side of her tongue for two years. The examination revealed a non-tender, soft to firm, 2x1 cm lump on the left side of the tongue, covered by healthy mucosa, with no signs of cervical lymph node enlargement. The lesion was completely excised under local anesthesia for histopathological evaluation. Histological examination revealed spindle cells with slender, undulating nuclei in Antoni A and B regions. The prominent nuclear palisading feature typical of schwannomas was evident.

Pediatric laryngeal schwannoma: a case report.

Schwannomas are benign tumors originating from Schwann cells in the peripheral nervous system. They mostly occur in the head and neck region but are rare in the larynx, and present with various symptoms. Surgical removal is the recommended treatment. This study presents a 12-year-old female with sudden onset hemoptysis, snoring, difficulty breathing, dysphagia, and voice changes. On examination, she was conscious and had muffled voice while speaking, without signs of respiratory distress. Endoscopic laryngoscopy revealed a large laryngeal mass obstructing the vocal cords. Endoscopic excision and biopsy confirmed the presence of the laryngeal schwannoma. Postoperative recovery was uneventful, with normal vocal cord function and no recurrence at follow-up.

Gastric schwannoma: Two case reports and review of the literature.

Gastric schwannomas are rare, slow-growing tumors whose clinical presentation is nonspecific. These are mostly benign, with a low probability of malignant transformation and an excellent prognosis. We present 2 cases of gastric schwannomas with distinct clinical features and imaging patterns, whose therapeutic approach differed. Case 1 is a 73-year-old woman with a voluminous subepithelial lesion in the greater gastric curvature, with predominantly endoluminal growth. Clinically the patient presented with nonspecific abdominal complaints and underwent complete surgical excision. Case 2 is a 69-year-old woman with an exophytic lesion adjacent to the gastric antrum, diagnosed incidentally and managed conservatively, with imaging follow-up, for the last 5 years and stable ever since. This article aims to focus on this rare disease, illustrating its main imaging findings, particularly in magnetic resonance imaging, along with pathological correlation, as well as reviewing the literature, discussing the differential diagnosis, and exploring clinical management and prognosis.

Intraoral Cellular Schwannoma Involving Maxillary Gingiva: A Rare Case Report.

Oral schwannomas (OSs) are uncommon benign nerve sheath tumors accounting for 1% of all schwannomas and may arise from either soft tissue or bone. Cellular schwannoma is a rare histological variant of schwannoma which is characterized by increased cellularity. The most common intraoral site of occurrence is the tongue followed by the floor of the mouth and palate. Here, we are reporting a rare case of intraoral cellular schwannoma involving both facial and palatal gingiva of the right maxilla in a young Indian male patient.

Ancient schwannoma in the parotid gland: A case report and review of the literature.

Schwannomas are uncommon neoplasms of neurologic origin that are rare in the salivary glands. A schwannoma that persists for a long time is referred to as an ancient schwannoma if it is accompanied by degenerative changes on histology. The case described herein involved a 37-year-old man with an ancient schwannoma that had persisted for 20 years in his right parotid gland. Clinically, the lesion presented with swelling and pain. Computed tomography revealed a well-defined, multilocular enhanced lesion. T2-weighted magnetic resonance images displayed multilocular hyperintensity, while T1-weighted images showed a high signal at the lobulated margin and a homogeneous low signal internally. The preoperative diagnosis, based on the lesion's location and imaging diagnosis, was Warthin's tumor. However, a biopsy conducted after surgical excision identified the lesion as a schwannoma with cystic degeneration. This report also presents a summary of the characteristics of rare cases of schwannoma in the major salivary gland based on this case and a literature review.

Schwannoma retroperitoneal primario. Presentación de un caso

Los schwannoma son tumores de tejidos blandos que se originan en las células de Schwann de la vaina nerviosa en los nervios periféricos, craneales o viscerales, en cualquier parte del cuerpo. Se trata de una entidad extremadamente inusual. En el artículo se describe el caso de un paciente de piel negra, 47 años de edad y con antecedentes de salud, quien acudió a consulta de clasificación, refiriendo que desde hacía un mes había comenzado a presentar dificultad para orinar, hasta llegar a la retención aguda de orina. Al examen físico se constató, mediante tacto rectal, esfínter tónico, ampolla rectal vacía, próstata aumentada de tamaño grado IV con consistencia fibromuscular de superficie lisa y móvil; no dolorosa. Tras realizarle estudios imagenológicos y complementarios, recibió tratamiento quirúrgico en el Hospital Provincial Docente Oncológico María Curie, de Camagüey, Cuba. Se le diagnosticó un schwannoma retroperitoneal, confirmado por el informe de Anatomía Patológica. Actualmente la evolución del paciente es favorable, sin tratamiento médico, pero con seguimiento periódico.

Schwannoma are soft tissue tumors that originate in Schwann cells of the nerve sheath in peripheral, cranial or visceral nerves, anywhere in the body. This is an extremely unusual entity. The article describes the case of a 47-years-old black-skinned patient with a history of health who attended a triage consultation, reporting that one month ago he had started having difficulty urinating, leading to acute urinary retention. The physical examination confirmed, through digital rectal examination, a tonic sphincter, an empty rectal ampulla, a grade IV enlarged prostate with a fibromuscular consistency with a smooth and mobile surface; not painful. After carrying out imaging and complementary studies, he received surgical treatment at the María Curie Provincial Oncological Teaching Hospital, in Camagüey, Cuba. He was diagnosed with a retroperitoneal schwannoma, confirmed by the Pathology report. Currently the evolution of the patient is positive, without medical treatment, but with periodic follow-up.

Diagnostic conundrums of schwannomas: two cases highlighting morphological extremes and diagnostic challenges in biopsy specimens of soft tissue tumors.

Schwannomas are benign, slow-growing peripheral nerve sheath tumors commonly occurring in the head, neck, and flexor regions of the extremities. Although most schwannomas are easily diagnosable, their variable morphology can occasionally create difficulty in diagnosis. Reporting pathologists should be aware that schwannomas can exhibit a broad spectrum of morphological patterns. Clinical and radiological examinations can show correlation and should be performed, in conjunction with ancillary tests, when appropriate. Furthermore, deferring a definitive diagnosis until excision may be necessary for small biopsy specimens and frozen sections. This report underscores these challenges through examination of two unique schwannoma cases, one predominantly cellular and the other myxoid, both of which posed significant challenges in histological interpretation.

A rare histopathological variant of Schwannoma with rosette-like arrangements and epithelioid cells: a case report from a histopathologist's perspective.

Schwannomas exhibit histopathological variation that leads to diagnostic dilemmas, although less frequent in the oral cavity. We describe a case with unique histopathology and no relevant clinical history that adds to the breadth of literature on the diversity presented by Schwannoma. A 60-year-old female patient presented with a small dome-shaped, asymptomatic swelling on the alveolar ridge 6 years in duration. Histopathologically, it showed rich cellular pathology with a unique arrangement of tumor cells forming irregular rosettes. Each rosette presented with a central core of fibrincollagenous material and the tumor cells were arranged on the periphery, exhibiting epithelioid change with evidence of mild cellular and nuclear pleomorphism. On immunohistochemical evaluation, the cells were strongly and diffusely positive for S-100 and negative for Ki-67. A diagnosis of benign Schwannoma with a rosette-like arrangement with epithelioid change was made. The case report emphasizes the risk of misdiagnosis and the importance of awareness regarding rare histopathological variants of Schwannoma.