Malignant Intracerebral Nerve Sheath Tumor Research Articles

First documented case of intracranial falcine malignant peripheral nerve sheath tumor: illustrative case.

BACKGROUNDThe authors reported the first documented case of intracranial extraaxial nonneurofibromatosis type 1–related nontriton malignant peripheral nerve sheath tumor (MPNST) originating from the falx cerebri.OBSERVATIONSA 34-year-old man with headache, short-term memory deficit, postural instability, and blurred vision presented with a large heterogenous contrast-enhanced intraventricular cystic lesion originating from the free margin of the falx cerebri. The patient received surgery using the right posterior interhemispheric approach. Gross total resection was performed, and the inferior border of the falx cerebri was resected. The postoperative course was uneventful. Histological examination revealed hypercellular foci of neoplastic spindle cells with hyperchromatic and wavy nuclei. Hence, a diagnosis of MPNST was made based on concomitant immunochemistry findings, including mouse double minute 2 homolog focal positivity and geographic loss of H3K27me3. The patient received adjuvant radiotherapy, and recurrence was not observed.LESSONSIntracranial MPNSTs are extremely rare tumors, typically originating from the cranial nerves in the posterior cranial fossa. An even rarer variant of these tumors, referred to as malignant intracerebral nerve sheath tumors, may directly arise from the brain parenchyma. The authors reported the first case of an intracranial MPNST originating from the dura mater of the falx cerebri, acting as an extraaxial lesion with prevalent expansion in the right ventricle.

When “Peripheral” Becomes “Central”: Primary and Secondary Malignant Intracerebral Nerve Sheath Tumor: A Case Report and a Systematic Review

The intracerebral occurrence of malignant peripheral nerve sheath tumors (MPNSTs) is exceedingly rare, and despite aggressive treatments, local recurrence and poor prognosis are very frequent. Like other brain tumors, these tumors could be primary or secondary, making the term "peripheral" an imprecise term for a primary brain tumor. To analyze the reported cases of primary and secondary cerebral MPSNTs in terms of diagnosis, treatment, and overall survival. Additionally, we present a case of malignant intracerebral nerve sheath tumor (MINST) treated with radical surgery and radiotherapy. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, one database (PubMed) and crossed references were queried for MPNST with brain metastasis and primary MINSTs from 1971 to 2020. Data regarding demographic features, primary tumor site, risk factors, brain location of the lesion, treatment applied, and overall survival were extracted. A total of 55 patients were selected (including the reported case): 29 patients were secondary brain MPNST and 26 patients were primary MINST. The mean age was 41.8± 22 and 31.2± 23 yr, respectively. All brain metastases of MPNST (100%) had a primary tumor elsewhere in the body at the time of diagnosis. The overall survival was significantly shorter in patients with a secondary brain MPNST compared to MINST (P=.002). We present a comprehensive analysis of every reported primary and secondary intracerebral MPNST. The prognosis in terms of survival is worst in the last one despite aggressive treatment. The lack of a primary MPNST in screening tests is sufficient to confirm a MINST at time of diagnosis.

Epithelioid Malignant Intracerebral Nerve Sheath Tumor: A Case Report and a Comparison with Conventional Type

Epithelioid Malignant Intracerebral Nerve Sheath Tumor: A Case Report and a Comparison with Conventional Type

Malignant Intracerebral Nerve Sheath Tumors: A Case Report with Review of the Literature

The occurrence of benign nerve sheath tumors within the neuroaxis is uncommon. Even rarer is the finding within brain parenchyma, termed malignant intracerebral nerve sheath tumors (MINST). We present a case of MINST which occurred in the frontal lobe of an 18-year-old male that recurred almost 4 years later. Imaging demonstrated a 4.0 cm lesion with an associated mass effect. He underwent a right fronto-parietal craniotomy for gross total resection. Pathology was inconclusive with a Glioblastoma Multiforme (GBM) as the most likely diagnosis, though gliosarcoma and MINST were also highly considered. Postoperatively, he was treated with chemotherapy and radiation and followed for almost 4 years, when an MRI indicated a recurrence. Resection of the recurrence was highly suggestive of MINST. Surgery was followed by radiation and chemotherapy, but, less than 7 months later, he was readmitted for a surgical-site infection, and, after multiple surgeries, and his family terminated care. Recognizing this unusual tumor in the differential diagnosis of a heterogeneously enhancing intracerebral mass can help surgeons diagnose and treat it. This report also exhaustively reviews the literature and presents diagnostic and treatment strategies.

A Long-Term Survival Case of a Primary Malignant Intracerebral Nerve Sheath Tumor

We report a long-term survival case of a primary malignant intracerebral nerve sheath tumor (MINST) occurring in the right frontal lobe of a 13-year old boy. After the gross total resection (GTR), we have performed radiation therapy but it recurred 50 months after the surgery, so the second GTR was performed. Later, second tumor recurrence was found 4 months after the second surgery. Subsequently the third GTR, radiotherapy, and chemotherapy were carried out. At present, the patient has been remaining alive for 77 months without evidence of tumor recurrence. According to the previous reports, the primary MINST is very rare : there are only 8 cases reported. It is also a fast-growing, invasive tumor with poor outcome. This is the first case that had no recurrence for 50 months after the surgery among the reported cases that had been followed up for more than 5 years. It is supposed that a period of recurrence free survival after GTR and low mitotic activity are associated with the patient's prognosis. A GTR followed by adjuvant radiation therapy and chemotherapy will be recommended to patients of MINST.

Sporadic primary malignant intracerebral nerve sheath tumors: case report and literature review

We report the case of a seventy-five year old woman with a sporadic primary malignant intracerebral nerve sheath tumor (MINST). These tumors fall within the spectrum of malignant peripheral nerve sheath tumors (MPNST) but confirming the diagnosis of a MINST can be difficult due to its rarity and unusual intraparenchymal location. Radiographically, MINST's mimic malignant glioma and should be considered in the differential diagnosis of enhancing cerebral lesions. In this report, we present a comprehensive panel of histological, immunohistochemical, ultrastructural, and genetic considerations that may be used to diagnosis MINST based on their similarities to MPNSTs and brain parenchyma location.

Malignant pediatric intracerebral nerve sheath tumor in neurofibromatosis type 1

Dear Editor: We read with interest the article by Oztanir et al., published in Child's Nervous System, describing a supratentorial malignant intracerebral nerve sheath tumor (MINST) in a 14-month-old girl with neurofibromatosis type 1 (NF-1) [1]. We wanted to bring attention to some points in regard to this article about this very rare tumor. The authors propose that MINST may have a propensity to be located infratentorially in adults and supratentorially in children and teenagers. However, three of the previous 11 reported cases of MINST (the authors had found six in their literature review) were located supratentorially in adults. De Cauwer et al. described a case of MINST in a 57year-old male in the right parietofrontal lobe [2]. Furthermore, there are two case reports of MINST of the lateral ventricles in 57and 40-year-old patients [3, 4]. The authors also state that this is the first report of the occurrence of MINST in the context of NF-1. However, there are three previous cases of this association in the literature, in both adults and children [2, 3, 5], granted these three other cases with NF-1 association have been reported with the triton variant of MINST. The imaging features of all previously described cases of MINST were nonspecific, mixed intensity-enhancing lesions, with presence of calcification in a minority of cases, features which did not allow differentiation from more commonly encountered tumors. However, there is a recent report on magnetic resonance spectroscopy (MRS) features in an intracerebral pontine malignant nerve sheath tumor in which Kozic et al. describe the presence of very high choline concentration associated with complete lack of creatine and NAA, suggesting the non-glial origin of the mass [6]. The actual usefulness of this finding in differentiating these tumors from other glial and non-glial tumors using MRS remains to be determined.

Malignant intracerebral giant nerve sheath tumor in a 14-month-old girl with neurofibromatosis type 1: a case report

Malignant intracerebral nerve sheath tumor (MINST) is extremely rare and the origin is still unclear. The authors present the clinical, radiological, and pathological features of a malignant intracerebral giant nerve sheath tumor. A giant tumor in the right frontotemporoparietal lobes causing a midline shift was detected in a 14-month-old girl who presented with developmental delay, vomiting, and lethargy. The physical examination was consistent with neurofibromatosis type 1 (NF-1). Subtotal resection was performed and the histopathological examination revealed the diagnosis of MINST. There are only six cases of malignant intracerebral nerve sheath tumor in the literature. The presented case is the youngest and the occurrence of MINST in a 14-month-old girl may support the hypothesis of multipotent mesenchymal stem cell origin; however, the tumors which arise from multipotent mesenchymal stem cells may be seen in later stages of life. Another important feature of the presented case is the occurrence of MINST in NF-1. MINSTs are extremely rare tumors with unknown origin. The location, the degree, and the size of the tumor and the general condition of the patient are prognostic factors in MINSTs, like in other malignant tumors.

Malignant intracerebral nerve sheath tumor

Intraparenchymal nerve sheath tumors of the central nervous system are rare, usually benign tumors. Three cases with tumor recurrences have previously been reported in the literature. The authors report a case of a malignant intracerebral nerve sheath tumor in a girl age 8 years and analyze the biologic characteristics of this tumor. The tumor was analyzed by histologic, immunohistochemical, and ultrastructural techniques. Magnetic resonance imaging revealed a mixed, attenuating, contrast-enhancing mass in the right posterior temporal lobe. Histopathology of the resected specimen revealed a uniformly S-100 positive and reticulin rich biphasic tumor with a characteristic distribution of spindle and epithelioid cells, with the latter almost entirely confined to the invading edge of the tumor. There was extensive brain infiltration in the form of lobules and fingerlike processes with a targetoid appearance. The spindle cells showed palisading and had elongated, wavy nuclei. Electron microscopy demonstrated basal lamina around both cell types with scattered Luse bodies in between. The patient is perfectly healthy and recurrence free 17 months after surgery. This represents the fourth and the youngest case in the literature of a malignant intracerebral nerve sheath tumor and highlights the distinctive clinicopathologic features of these tumors. First, these tumors have very great infiltrative potential, as observed histopathologically and reflected in their frequent recurrences. Second, epithelioid cells confined to the infiltrative edge suggest their aggressive role. Epithelioid cells have been shown to represent a malignant component of systemic schwannomas with malignant transformation; however, this case does not have any evidence of origin from a preexisting benign schwannoma. Third, despite histologic similarities to neuraxial desmoplastic neuroepithelial tumors, none of the malignant schwannomas had any evidence of divergent differentiation towards astrocytic or neuronal lineage, and had a much worse prognosis. Fourth, the event free survival after initial resection appears to be an important predictor of overall survival in the reviewed cases. Chemotherapy and radiation therapy have not been successful in the treatment of this rare entity. Hence, an accurate diagnosis and planned extensive resection appear to be the key elements in its management.