Primary peripheral nerve lymphoma: a case report and literature review.

Neurolymphomatosis (NL) is an uncommon malignant lymphoma characterized by selective infiltration of the central and peripheral nervous system. In this case report, we present a patient diagnosed with diffuse large B-cell lymphoma who initially manifested with peripheral neuropathy, primarily characterized by weakness of the left lower limb. By exploring its clinical manifestations, ancillary tests, and reviewing the relevant literature, we aim to deepen our understanding, diagnosis, and treatment of this disease. A 48-year-old male patient presented to the Department of Neurology, Hematology, and Neurosurgery with complaint of left lower limb weakness that had persisted for over 11 months. Initial laboratory tests and cerebrospinal fluid analysis yielded negative results. Electromyography examination indicated damage to the left lumbar plexus and iliac plexus nerves raising suspicions of nerve root involvement. Enhanced MRI of the lumbosacral plexus nerves revealed thickening and enhanced signals in left nerve roots at T12-L1, L1-2, and L3-4 levels. Additionally, local thickening and enhancement of signals were observed in the left erector spine muscle, psoas major, and iliopsoas muscles compared to the contralateral side. PEC/CT imaging displayed multiple soft tissue density shadows in the left foraminal area at the T12-1 and L1-2 levels. Bone marrow examination excluded hematological disease. Subsequent biopsy of the left foraminal nerve root at T12-L1 and the vertebral muscle at L3 level confirmed a diagnosis of diffuse large B-cell malignant lymphoma, indicating PNSL due to the involvement of multiple nerve roots. Following diagnosis, the patient underwent chemotherapy, resulting in the alleviation of his symptoms. Diagnosing PNSL can be challenging due to the nonspecific clinical manifestations and often inconclusive laboratory test results. Misdiagnosis and delayed diagnosis are common pitfalls. Electromyography may reveal damage to the affected peripheral nerves, while MR imaging might show nerve root thickening, and PET/CT can demonstrate increased lesion uptake. However, the definitive diagnosis relies on a biopsy of the lesion. Treatment for PNSL typically involves chemotherapy.

Rapidly Growing Leiomyoma Mimicking Schwannoma of the Saphenous Nerve in the Lower Extremity: An Unusual Case Report.

Leiomyomas and schwannomas are both types of rare benign soft tissue tumours. Leiomyomas are more commonly found in the lower limbs than in the upper extremities, while schwannomas are rare peripheral nerve sheath tumours that can occur in different anatomical regions. However, they rarely occur in the saphenous nerve. This case study presents a 41-year-old female patient with a solitary mass lesion located deep in the soft tissue of the anteromedial lower extremity. The physical examination revealed a palpable, elastic-hard, mobile and non-tender mass. Magnetic resonance imaging (MRI) showed an oval-shaped subcutaneous mass on contrast-enhanced T1-weighted sections. The initial MRI images suggested a schwannoma, but the tumour was later confirmed to be a leiomyoma after total enucleation. An immunohistochemical study was performed for differential diagnosis. Solitary mass lesions in the lower extremities can be mistaken for various types of tumours and misdiagnosed and require histopathological examination and good radiological imaging for differential diagnosis. Complete surgical excision is usually a safe and effective treatment for leiomyomas.

Giant Common Peroneal Nerve Schwannoma Mimicking Synovial Sarcoma: An Unusual Case Report.

Schwannoma, also known as neurilemmoma or Schwann cell tumor, is one of the most common neoplasms of the nerve sheath which usually appears at the head, neck, or upper extremity. Schwannoma occurrence in the lower extremity originating from the common peroneal nerve is rarely reported according to literary findings. We report a case of a 32-year-old man who presented with a 6-month history of a growing lump in the left knee. MRT revealed a well-defined 9.6 cm × 7.8 cm × 6.5 cm multilobular mass of heterogeneous consistency with areas of necroses with a likely diagnosis of synovial sarcoma. After surgery, a final histopathological assessment of the tumor demonstrated Antoni A and B patterns with nuclear palisading, hallmarks of a schwannoma. Postoperatively the patient suffered a neurological complication-impaired dorsiflexion of the left foot. The patient started immediate physiotherapy in the Department of Rehabilitation. Three weeks after the operation, gradual improvement in neurological function was observed. To date, complete tumor excision combined with microscopic analysis and immunohistochemical staining remains the gold standard in diagnosing and treating a peripheral nerve schwannoma. Moreover, the use of additional nerve monitoring tools during surgery could help to prevent complications.

Differentiation of Peripheral Nerve Tumors in the Brachial Plexus.

Schwannomas are benign extracranial nerve sheath tumors that can rarely affect the brachial plexus. Due to the relative rarity of these tumors and the complexity of the anatomy of the neck and shoulder, these tumors are a challenging diagnosis for clinicians. We present a case report of a 51-year-old male with a brachial plexus schwannoma definitively treated with surgical resection. It is our hope that this case serves as a reminder to consider schwannomas in the differential diagnosis for infraclavicular tumors.

Paraganglioma of the cauda equina: a tertiary centre experience and scoping review of the current literature.

Cauda equina paragangliomas are rare benign extra-adrenal neuroendocrine tumours arising from the neural crest cells associated with autonomic ganglia. These tumours are often mistaken preoperatively for ependymomas or schwannomas. Patients present with axial or radicular pain with or without neurological deficits. Recurrence, secretory features and length of follow-up are controversial. We conducted a retrospective cohort study of paraganglioma through searching a prospectively maintained histopathology database. Patient demographics, presentation, surgery, complications, recurrence, follow-up and outcome between 2004 and 2016 were studied. The primary aim was to collate and describe the current evidence base for recurrence and secretory features of the tumour. The secondary objective was to report outcome and follow-up strategy. A scoping review was performed in accordance with the PRISMA-ScR Checklist. Ten patients were diagnosed (M:F 7:3) with a mean age of 53.6 ± 5.1 (range 34-71 years). MRI scans revealed intradural lumbar enhancing lesions. All patients had complete microsurgical excisions without adjuvant therapy with no recurrence with a mean follow-up of 5.1 ± 1.4 years. Tumours were attached to the filum terminale. Electron microscopic images demonstrated abundant neurosecretory granules with no evidence of catecholamine production. A total of 620 articles were screened and 65 papers (including ours) combining 121 patients (mean age 48.8 and M:F 71:50) were included. The mean follow-up was 3.48 ± 0.46 (range 0.15-23 years). Back pain was the most common symptom (94%). Cure following surgery was achieved in 93% of the patients whilst 7% had recurrence. Total resection likely results in cure without the need for adjuvant therapy or prolonged follow-up. However, in certain situations, the length of follow-up should be determined by the treating surgeon.

Paraganglioma of the cauda equina: A clinicopathologic study of 12 cases with demonstration of cytokeratin positivity.

Paragangliomas are rare neuroendocrine tumors originating from neural crest-derived paraganglion cells. Primary cauda equina paraganglioma (CEP) pose both diagnostic and surgical challenges. We report 12 cases of CEP to characterize the diagnostic and operative approach to these rare tumors. 12 cases with primary CEP were studied; 5 patients were male (41.7%) and 7 were female (56.3%). The median age was 44 years (range: 15-64 years). The most common symptom was lower back pain of variable duration. Radiologically, the lesions were intradural and extramedullary with well-defined margins, and ranged from 1 to 4.5 cm. in diameter (mean: 1.65 cm). 9 tumors were composed of sheets and nests of cells with a neuroendocrine pattern and intense vascularity and displayed a characteristic Zellballen pattern. Interestingly, CAM 5.2 was diffusely or focally positive with a dot-like or membrane pattern in 8/11 cases (72.7%). Similarly, CK was diffusely or focally positive with membrane and cytoplasmic staining or with a dot-like pattern in 7/11 (63.6%) and 2/11 cases (18.2%). None of the cases showed deletion of SDHB nor expression of GATA3. CEP can display aberrant keratin positivity, and this should be considered in the differential diagnosis of these lesions. This finding also raises the possibility that CEP may be an entirely different entity than non-spinal paragangliomas.

Saphenous nerve schwannoma as a cause of vascular claudication - case report and review of the literature.

Schwannomas are peripheral nerve tumours that are uncommon. They typical present with a palpable mass, pain or neurological changes. We describe a saphenous nerve schwannoma compressing the superficial femoral artery and causing vascular claudication. We also review the literature.

Peripheral nerve sheath tumor: differentiation of malignant from benign tumors with conventional and diffusion-weighted MRI.

OBJECTIVES: To evaluate potential of conventional MRI and diffusion-weighted imaging (DWI) for differentiating malignant from benign peripheral nerve sheath tumors (PNSTs). METHODS: Eighty-seven cases of malignant or benign PNSTs in the trunk or extremities that underwent conventional MRI with contrast enhancement, DWI, and pathologic confirmation between Sep. 2014 and Dec. 2017 were identified. Of these, 55 tumors of uncertain nature on MRI were included. Tumor size, signal, and morphology were reviewed on conventional MRI, and apparent diffusion coefficient (ADC) values of solid enhancing portions were measured from DWI. Patient demographics, MRI features, and ADC values were compared between benign and malignant tumors, and robust imaging findings for malignant peripheral nerve sheath tumors (MPNSTs) were identified using multivariable models. RESULTS: A total of 55 uncertain tumors consisted of 18 malignant and 37 benign PNSTs. On MRI, tumor size, margin, perilesional edema, and presence of split fat, fascicular, and target signs were significantly different between groups (p < 0.05), as were mean and minimum ADC values (p = 0.002, p < 0.0001). Most inter-reader agreement was moderate to excellent (κ value, 0.45-1.0). The mean ADC value and absence of a split fat sign were identified as being associated with MPNSTs (odds ratios = 13.19 and 25.67 for reader 1; 49.05 and 117.91 for reader 2, respectively). The C-indices obtained by combining these two findings were 0.90 and 0.95, respectively. CONCLUSIONS: Benign and malignant PNSTs showed different features on MRI and DWI. A combination of mean ADC value and absence of split fat was excellent for discriminating malignant from benign PNSTs. KEY POINTS: • It is important to distinguish between malignant peripheral nerve sheath tumors (MPNSTs) and benign peripheral nerve sheath tumors (BPNSTs) to ensure an appropriate treatment plan. • On conventional MRI and diffusion-weighted imaging (DWI), MPNSTs and BPNSTs showed significant differences in tumor size, margin, presence of perilesional edema, and absence of split fat, fascicular, and target signs. • Absence of a split fat sign and mean apparent diffusion coefficient (ADC) values were robust imaging findings distinguishing MPNSTs from BPNSTs, with a C-index of > 0.9.

Lymphomatosis cerebri with cauda equina lymphoma.

PURPOSE/AIM: Lymphomatosis cerebri (LC) and cauda equina lymphoma are both rare forms of primary central nervous system lymphoma (PCNSL). LC is characterized by diffuse bilateral non-enhancing (or partially enhancing) inltrative lesions without mass effect, which can be easily confused with other forms of leukoencephalopathy and, thus, lead to delays in diagnosis. CASE REPORT: For the first time, a case of LC concomitant with cauda equina involvement confirmed by brain stereotactic biopsy is presented. CONCLUSIONS: This case highlights the necessity of using a multimodal strategy in diagnosing PCNSL, including multimodal magnetic resonance, cerebral spinal fluid cytology, flow cytometry and fluorodeoxyglucose positron emission tomography/computed tomography.

Peripheral nerve neurolymphomatosis: Clinical features, treatment, and outcomes.

This series characterises nine patients with neurohistopathologically proven peripheral nerve neurolymphomatosis. A search of the hospital neuropathology database from 2002 to 2019 identified biopsy proven cases. Clinical data, investigation modalities, treatments, and outcomes were collated. Median age at neuropathy onset was 47 y, the neuropathy commonly as the initial lymphoma disease manifestation. Most (8/9) presented with painful asymmetrical sensory disturbance, with additional cranial nerve involvement in three. Neurophysiology typically demonstrated multiple axonal mononeuropathies. Cerebrospinal fluid protein was often raised (6/8). Magnetic resonance imaging suggested peripheral nerve infiltration in 6/9 and positron emission tomography CT in 4/9. Bone marrow biopsy was abnormal in 6/8. Treatment involved systemic or intrathecal chemotherapy and radiotherapy. Median survival was 23 mo. Neurolymphomatosis is a rare but important cause of neuropathy, particularly in those lacking systemic evidence of lymphoma as correct aggressive treatment can prolong survival. Nerve biopsy is essential to classify lymphoma type and rule out alternatives.

High mitotic activity in a capillary hemangioma of the cauda equina: Case report and review of the literature.

BACKGROUND: Capillary hemangiomas of the skin and soft tissue are a common entity, while capillary hemangiomas of the central nervous system are an extremely rare pathology. There are less than 20 published cases of intradural lesions involving the cauda equina. CASE PRESENTATION: Herein, we describe a young patient with a capillary hemangioma of the cauda equina that underwent successful surgical resection. CONCLUSION: Natural history and post-operative follow-up for patients with spinal intradural capillary hemangioma are uncertain. This is the sole case to have not recurred at 12 months which underwent gross total resection and had a high proliferative index.

Primary peripheral nerve tumors associated with nerve-territory herpes zoster.

Herpes viruses have been described as markers of occult cancer and have also been implicated in oncogenesis. This group of viruses includes varicella-zoster virus (VZV) which is well-known for its ability to evade the immune response by lying dormant in the dorsal root ganglion of peripheral nerves. Although it is common knowledge that VZV reactivation causes herpes zoster (shingles), there have been no reports in literature of herpes zoster manifesting in the dermatomal territory of peripheral nerves involved by either benign or malignant tumors. We report two cases of patients with peripheral nerve tumors who presented with herpes zoster in the dermatomal distribution of the involved nerves. One patient had primary neurolymphomatosis, whereas the other had a sacral schwannoma. We believe these are the first cases to be reported that demonstrate herpes zoster at clinical presentation in patients with peripheral nerve tumors. This suggests that VZV may have the potential to cause peripheral nerve tumors via a complex interplay of viral oncogenes and alterations in host immunological responses.

Filum Terminale Ependymoma in an Infant with Meningocele.

This report describes a case of an ependymoma found in the setting of tethered cord syndrome. We present a 3-month-old girl with prenatal diagnosis of lumbar meningocele who later underwent tethered cord release. After birth, she was neurologically intact and only found to have a skin-covered meningocele. An MRI was obtained and significant for low-lying conus terminating at L5, a focal syrinx, and Chiari II malformation. She underwent an elective meningocele repair and resection of thickened filum for tethered cord release at 3 months of age. Unexpectedly, microscopic evaluation of the filum was consistent with a small focus of ependymoma in addition to the filum tissue. Previous case reports have suggested a link between thickened filum in the setting of spinal dysraphism and myxopapillary ependymoma, but to our knowledge, this is the first report of ependymoma in the setting of tethered cord syndrome.

[Paraganglioma of the cauda equina region: Report of 9 cases]. / Paragangliome de la queue de cheval : à propos d'une série de 9 cas.

INTRODUCTION: The paraganglioma of the cauda equina is a rare tumor, the diagnosis is morphological and the immunohistochemistry provides a definite diagnosis. The objective of our study is to specify the clinical signs, radiological and associated pathological criteria and to compare our data with those of the literature. PATIENTS AND METHOD: This is a retrospective study of nine cases of paragangliomas of the cauda equina diagnosed in our department from 2003 to 2018. The median age of the patients was 50 years-old with a male predominance (sex ratio: 3,5/1). All patients had preoperative magnetic resonance imaging (MRI) and surgery to remove the tumor. The diagnosis was performed after HES (Hematoxylin Eosin Saffron) and immunohistochemical sections examination. RESULTS: Radiculalgia was the chief symptom of these tumors. MRI showed an oval lesion uniformly enhanced by Gadolinium in the eight patients whose records were available. Histologically, the tumors had a lobular and trabecular pattern with neuroendocrine-like cells and a rich vascularization. By immunohistochemistry, the cells expressed chromogranin, synaptophysin and CD56. DISCUSSION AND CONCLUSION: Paragangliomas of the cauda equina are rare, benign tumors. Except for cases of secreting tumors, the preoperative diagnosis is difficult. MRI is useful and may reveal radiological features suggestive of these tumors. However, it is rare for the diagnosis to be made before surgery. The diagnosis is established by histological examination and immunohistochemical techniques must be used to confirm the diagnosis. The paragangliomas of the cauda equina are well encapsulated tumors whose complete excision is curative. When the excision is incomplete, treatment with radiotherapy is recommended. Long-term clinical and radiological monitoring is recommended because of the slow evolution of the tumor and the potential for recurrence.

[Hereditary predisposition to tumors of the central and peripheral nervous systems]. / Prédisposition héréditaire aux tumeurs des systèmes nerveux central et périphérique.

Some tumors of the central and peripheral nervous system may be associated with a cancer predisposition syndrome, either hereditary or occurring de novo. Such a syndrome is usually associated with multiple tumors occurring early in life. Patients with neurofibromatosis type 1 present with multiple neurofibromas, especially of the plexiform type (which may transform into malignant peripheral nerve sheath tumor), and pilocytic astrocytomas of the optic pathways. Neurofibromatosis type 2 patients present with multiple schwannomas (typically bilateral vestibular schwannomas), meningiomas, and ependymomas. Li-Fraumeni syndrome (germline TP53 mutation) is associated with choroid plexus tumors (carcinomas), medulloblastomas, and diffuse astrocytomas. Multiple hemangioblastomas are characteristic of von Hippel-Lindau syndrome while subependymal giant cell astrocytomas are pathognomonic of tuberous sclerosis complex. Dysplastic cerebellar gangliocytomas of adult patients occur in Cowden syndrome. Turcot syndrome overlaps with constitutional mismatch repair deficiency syndrome (CMMRD), which is associated with giant cell glioblastomas. Rhabdoid tumor predisposition syndrome (germline mutation of SMARCB1/INI1) is associated with atypical teratoid/rhabdoid tumors. Tumors arising in the setting of a cancer predisposition syndrome develop along specific genetic pathways. Some histopathological and immunohistochemical characteristics of these tumors may point toward such a syndrome. The diagnosis of a cancer predisposition syndrome is of tremendous importance to the patients and their families who require genetic counseling and long-term follow-up.

Ganglioneuroblastoma in children.

INTRODUCTION: Neuroblastoma ranks third among pediatric malignancies. CASE REPORT: The case of a 3-year-old child is presented, who suddenly had frequent, unproductive, emetic cough; fever; and weight loss. Lung X-ray showed an opacity situated in the posterior superior mediastinum. Thoracic ultrasound revealed a slightly inhomogeneous, hypoechoic mass located in the posterior superior mediastinum. Computed tomography evidenced a tumor mass with homogeneous appearance in the costo-vertebral groove. Histological examination confirmed the diagnosis of ganglioneuroblastoma. CONCLUSION: Although history and clinical examination provided few elements, diagnosis was made based on imaging and histopathological examination.

Pediatric peripheral nerve tumors: clinical and surgical aspects.

PURPOSE: Pediatric peripheral nerve tumors (PNTs) are rare. Most are related to neurofibromatosis type 1 (NF1) with the potential for malignancy. An ongoing debate occurs about the best approach to such patients. This study describes a cohort of pediatric patients with PNTs and discusses clinical characteristics and surgical treatment. METHODS: We retrospectively reviewed the charts of seven pediatric patients with eight PNTs surgically treated from 2007 to 2018. Information concerning patient demographics, clinical presentation, PNTs characteristics, treatment choice, and outcome were recorded. RESULTS: All children presented with intense pain and a palpable mass. Three of the eight tumors were associated with a neurological deficit. Among the four patients with NF1, two had a neurofibroma and two a malignant peripheral nerve sheath tumor (MPNST). Histologically, three of the lesions were a benign peripheral nerve sheath tumor (BPNST), three a MPNST, and one each a desmoid tumor and Ewing's sarcoma. Two of the eight tumors underwent partial tumor excision and six gross total excisions. CONCLUSIONS: Intense pain at rest, day, and/or night, preventing normal activities; a palpable, hard, immobile mass; an intense Tinel's sign related to the lump; clinical evidence of NF1; and high-speed growth of a tumor in the trajectory of the nerve or plexus should alert the clinician to the potential for malignancy. Preoperative biopsy is not indicated when clinical and imaging findings suggest a benign tumor. The surgical management of PNTs must be to achieve total resection, including wide margins with malignant tumors, though this is not always possible.

Diagnostic Criteria for Symptomatic Neuroma.

INTRODUCTION: After nerve injury, disorganized or incomplete nerve regeneration may result in a neuroma. The true incidence of symptomatic neuroma is unknown, and the diagnosis has traditionally been made based on patient history, symptoms, physical examination, and the anatomic location of pain, along with response to diagnostic injection. There are no formally accepted criteria for a diagnosis of neuroma. MATERIALS AND METHODS: A literature search was performed to identify articles related to neuroma: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed and Pubmed, Embase, and the Cochrane Library were searched for all relevant articles pertaining to neuroma. Articles were screened by title and abstract for relevance. If an article was considered potentially relevant, the full article was reviewed. After consideration, 50 articles were included in this systematic review. RESULTS: No previous articles directly addressed diagnostic criteria for symptomatic neuroma. Factors related to neuroma diagnosis gleaned from previous studies include pain and cold intolerance (patient history), positive Tinel sign or diminished 2-point discrimination (physical examination findings), response to diagnostic nerve block, and presence of neuroma on diagnostic imaging (ultrasound or magnetic resonance imaging). Based on literature review, the importance and number of references, as well as clinical experience, we propose criteria for diagnosis of symptomatic neuroma. To receive a diagnosis of symptomatic neuroma, patients must have (1) pain with at least 3 qualifying "neuropathic" characteristics, (2) symptoms in a defined neural anatomic distribution, and (3) a history of a nerve injury or suspected nerve injury. In addition, patients must have at least 2 of the following 4 findings: (1) positive Tinel sign on examination at/along suspected nerve injury site, (2) tenderness/pain on examination at/along suspected nerve injury site, (3) positive response to a diagnostic local anesthetic injection, and (4) ultrasound or magnetic resonance imaging confirmation of neuroma. CONCLUSIONS: The diagnosis of neuroma is based on a careful history and physical examination and should rely on the proposed criteria for confirmation. These criteria will be helpful in more precisely defining the diagnosis for clinical and research purposes.

Myxopapillary ependymoma of cauda equina presented with communicating hydrocephalus and papilloedema: A case report.

We reported a case of cauda equina myxopapillary ependymoma in a patient who presented with atypical history of progressive blurring of vision. Ophthalmology examination revealed relative afferent pupillary defect, binasal hemianopia and papilloedema. This case report serves as a reminder that the intraspinal tumour could be a cause of papilloedema, despite rare, should be considered in a hydrocephalus patient who presented with no intracranial pathology and minimal spinal symptoms.

Bilateral Nonsynchronous Pacinian Corpuscle Neuroma.

Pacinian corpuscles are rapidly adapting mechanoreceptors distributed in the dermis of the fingers and palm of the hand. A neuroma of the pacinian corpuscle is rare and extremely painful, with only a few cases reported in the literature. A 71-year-old man with pain and swelling on his left index finger, initially diagnosed as tenosynovitis resistant to nonsurgical treatment, was referred to our center. During surgery, a cluster of spherical, gray lesions close to the digital nerve was found and excised. The pathological diagnosis was neuroma of the pacinian corpuscles. Two years later, he reported the same clinical findings on his right index finger with no improvement after nonsurgical treatment. During surgery, the same lesions were found and also identified as pacinian corpuscle neuromas.