Malignant peripheral nerve sheath tumours in the head and neck region: retrospective analysis of clinicopathological features and treatment outcomes

Malignant peripheral nerve sheath tumour of the cerebellopontine angle in a cat

Malignant peripheral nerve sheath tumour is an uncommon tumour in cats. The current case report aims to present the diagnosis, treatment and histopathology of a malignant peripheral nerve sheath tumour that developed in the cerebellopontine angle region of a cat. A 4-year-old 4.2-kg female calico cat was brought to the animal hospital with the complaints of loss of balance, leaning against the wall and behavioural changes. During the neurological examination, the patient was observed to have a right-sided head tilt accompanied by ipsilateral ventral strabismus. On magnetic resonance imaging scan, a mass was identified at the right cerebellopontine angle. The surgical removal of the mass was carried out using a caudo-tentorial approach. The histopathological analysis revealed the presence of a malignant peripheral nerve sheath tumour. This case report contributes to the existing knowledge in the field presenting the characteristics of a malignant peripheral nerve tumour that was not associated with any nerve in the cerebellopontine angle in a cat.

Clinicopathological study of malignant peripheral nerve sheath tumors in the head and neck: Case reports and review of literature

BACKGROUND

Malignant peripheral nerve sheath tumor (MPNST) is a rare and aggressive soft tissue sarcoma that poses a major diagnostic and therapeutic challenge.

CASE SUMMARY

We retrospectively reviewed patients with head and neck MPNSTs treated in our hospital from 2000 to 2021. The clinical features, pathological manifestations, treatments, and prognoses were summarized. We also reviewed the literature, focusing on MPNST in the mandible and maxilla. The study population consisted of five women and five men aged 22-75 years (mean age, 49 years). Of the 10 patients, 7 were initial cases and 3 were recurrent cases. All lesions were sporadic. The most common site was the mandible. The most frequently encountered symptoms were a progressive mass and local swelling. Complete or partial loss of trimethylation at lysine 27 of histone H3 (H3K27me3) was evident on staining in four of nine cases (one case was excluded due to lack of tissue for evaluation of loss of H3K27me3). The 2- and 5-year disease-specific survival rates were 86% and 43%, respectively. The average survival time was 64 mo.

CONCLUSION

MPNST is a highly malignant tumor with a poor prognosis, prone to a high risk of recurrence and distant metastasis. Complete surgical resection is the main treatment.

Malignant peripheral nerve sheath tumour of the oral and maxillofacial region-A systematic review

To integrate the available data published on malignant peripheral nerve sheath tumours (MPNST) of the oral and maxillofacial region. Searches in Embase, PubMed, Web of Science and Scopus were conducted for the identification of case reports/case series in English language. The risk of bias was assessed using the Joanna Briggs Institute tool. Outcomes were evaluated by Cox regression and Kaplan-Meier methods. A total of 306 articles were retrieved, 50 of which reporting 57 MPNST were included. The lesion showed a predilection for the mandible (n = 18/31.57%) of middle-aged adults (~40.5 years) with a male/female ratio of 1.1:1. The individuals were mostly symptomatic with a mean evolution time of 9.6 months. Surgical removal plus adjuvant therapy (especially radiotherapy) was the main approach (51.86%). Recurrence was reported in 39.62% of cases. Nodal and distant metastases were identified in 28.26% and 26.66% of cases, respectively. The 2-year cumulative survival rate was 55%. Independent predictors of poor survival were the presence of neurofibromatosis type 1 (p = 0.04) and distant metastases (p = 0.004). The diagnosis of MPNST is challenging due to the variety of its clinical and histopathological presentations. Local aggressiveness and the potential for metastases are common outcomes of this neoplasm.

Incidence and prognosis of distant metastasis in malignant peripheral nerve sheath tumors

BACKGROUND

Malignant peripheral nerve sheath tumors (MPNSTs) are a type of soft tissue sarcomas (STS) with recurrence and metastatic potential. We aimed to investigate the risk factors for developing distant metastases (DM) and to identify the prognostic factors in patients with DM.

METHODS

Based on the Surveillance, Epidemiology, and End Result (SEER) database, MPNST patients diagnosed between 2010 and 2016 were extracted in our study. The logistic regression model was performed for predicting DM development while the Cox proportional hazard regression model was conducted for revealing the prognostic factors.

RESULTS

Eventually, 764 patients diagnosed with MPNSTs were included with 109 cases presenting with metastases at initial diagnosis. Larger tumor size and lymph node metastases were independent risk factors for developing DM. The median overall survival (OS) for patients with metastases was 8.0 (95% CI: 6.1-9.9) months. Multiple metastatic sites and no surgical treatment were prognostic factors for worse survival. Tumors located in non-head and neck region were related with better survival.

CONCLUSIONS

The incidence of DM was 14.3% with a dismal median OS of 8.0 months for metastatic MPNSTs. More evaluation should be applied for patients with large tumor size and lymph metastases. Tumors located in head and neck region and the presence of multiple metastases predicted worse survival outcome. Surgical treatment can significantly improve the survival of MPNST patients with distant metastasis.

Embryonic stem cell-like subpopulations are present within Schwannoma

BACKGROUND

There is accumulating evidence of the presence of embryonic stem cell (ESC)-like cells in benign tumors.

AIM

This study aimed to identify ESC-like cells in Schwannoma using the induced-pluripotent stem cell (iPSC) markers OCT4, SOX2, NANOG, KLF4 and c-MYC.

METHODS

Immunohistochemical (IHC) staining (n = 20) and RT-qPCR (n = 6) were performed on Schwannoma tissue samples (STS) to investigate protein and mRNA expression of these iPSC markers, respectively. Immunofluorescence (IF) staining was performed to investigate co-localization of the iPSC markers with CD34, α-SMA and CD133.

RESULTS

IHC staining and RT-qPCR demonstrated protein and mRNA expression of all five iPSC markers, respectively. IF staining showed expression of SOX2, KLF4 and c-MYC on the tumor cells and the endothelium of the tumor microvessels which also expressed OCT4, while NANOG was exclusively expressed on the endothelium of the tumor microvessels. The OCT4+/CD34+ endothelium expressed CD133.

CONCLUSION

We have identified a putative OCT4+/SOX2+/NANOG+/KLF4+/c-MYC+/CD133+ ESC-like subpopulation on the endothelium of tumor microvessels and an OCT4-/SOX2+/NANOG-/KLF4+/c-MYC+/CD133+ ESC-like subpopulation, within Schwannoma.

Prognosis and risk factors for malignant peripheral nerve sheath tumor: a systematic review and meta-analysis

Background

No available meta-analysis was printed to systematically introduce the MPNST clinic outcome and risk factors based on largely pooled data. This systematic review and meta-analysis aimed to investigate 5-year OS rate, 5-year EFS rate, and LR rate for MPNST, and to assess potential risk factors for prognosis.

Methods

Electronic articles published between January 1, 1966 and February 29, 2020 were searched and critically evaluated. The authors independently reviewed the abstracts and extracted data for 5-year OS rate, 5-year EFS rate, LR rate, and potential risk factors for prognosis.

Results

Twenty-eight literatures were finally included for meta-analysis. The pooled 5-year OS rate, 5-year EFS rate, and LR rate were 49%, 37%, and 38%, respectively. The significant prognostic factors for survival were NF1 status, tumor size, depth, location, malignant grade, margin status, chemotherapy, and radiotherapy. Age and sex were not associated with survival.

Conclusion

Survival and local recurrence of MPNST are poor. Worse prognosis is mainly associated with NF 1, large size, deep to fascia, high grade, metastases, and location (trunk and head and neck). Complete resection with adequate surgical margins is the mainstay protective factor of MPNST patients, following necessary adjuvant therapies.

Giant Malignant Peripheral Nerve Sheath Tumor of the Scalp: Case Report and Review of the Literature

BACKGROUND

Malignant peripheral nerve sheath tumors (MPNSTs) are rare nervous system tumors that rarely appear on the scalp. About half of the scalp MPNSTs described in the literature have reached giant dimensions at the time of diagnosis. The surgical treatment is the gold standard for this type of tumor. Some authors suggest adjuvant radiotherapy for local tumor control, although there is uncertainty about its advantages and its use is not without risks.

CASE DESCRIPTION

We present the case of a 31-year-old man who presented with a large necrotic scalp tumor of the left frontoparietal convexity. magnetic resonance imaging showed a large extra-axial tumor, measuring 17 x 17 x 8 cm, centered on the soft tissues, with skull erosion and signs of dural invasion, although with no intradural component. The tumor was surgically removed and the osteocutaneous defect was reconstructed with a latissimus dorsi muscle free flap. The anatomopathologic diagnosis was MPNST. The patient then underwent adjuvant radiotherapy. After 7 months he developed a progressive right hemiparesis and magnetic resonance imaging showed results compatible with cerebral radiation necrosis. This motor deficit improved with corticotherapy. After 9 months the patient went back to his home country and was subsequently lost to follow-up.

CONCLUSIONS

Giant MPNSTs of the scalp are highly aggressive lesions that should primarily be treated in a surgical fashion. Although adjuvant radiotherapy has been used routinely for local tumor control, there is uncertainty about its advantages.

An unusual presentation of intraosseous malignant peripheral nerve sheath tumour of mandible

Malignant peripheral nerve sheath tumour (MPNST) is a rare mesenchymal tumour which usually presents high grade malignancy. We report an atypical case of intraosseous malignant peripheral nerve sheath tumour on mandible in a 36-year-old male. Patient presented with an incidentally discovered radiolucency on the left anterior mandible and did not complain of any symptoms. Panoramic radiograph and computed tomography showed enlargement of inferior alveolar nerve canal, thinning of the cortex and calcified foci within an expansile mass. Magnetic resonance images revealed heterogeneous hyperintense signal intensity with a well-defined margin on T₂ weighted images, heterogeneous enhancement on contrast-enhanced T₁ weighted images and intermediate signal intensity and inferior alveolar nerve canal enlargement on T₁ weighted images. In spite of benign radiologic characteristics as mentioned above, histopathologic examination of biopsied specimen otherwise revealed a low-grade malignancy. Wide excision of mandible was performed and there has been no loco-regional recurrence or distant metastasis over 1 year following surgery. This case indicates that, even when imaging modalities clearly demonstrate benign nature of intraosseous neurogenic tumour, care must be taken to establish proper treatment plan for assumed malignancy with a definitive histopathological analysis.

Comprehensive Analyses of Intraoral Benign and Malignant Nerve Sheath Tumors: The Rare Disease Entities Revisited

INTRODUCTION

Intraoral benign and malignant nerve sheath tumors (BNST and MNST) are rare tumors with non-specific clinical presentations and represent diagnostic and therapeutic challenges. Current knowledge regarding their demographic, clinicopathological features and treatments remains fragmented.

MATERIALS AND METHODS

The original data about patients diagnosed as intraoral BNST and MNST were retrieved from our disease registry (2005-2017). Comprehensive reviews of English and Chinese literature were performed to collect and analyze the epidemiological, clinicopathological data and treatment outcomes about those published cases.

RESULTS

Thirty-four intraoral BNSTs were found at our institution in the past 13 years. Literature reviews identified 354 intraoral BNSTs in 223 articles and 60 intraoral MNSTs in 50 articles. Most intraoral BNSTs and MNSTs were presented in the second to fifth decade of life. Males outnumbered females in MNSTs, while BNSTs displayed a slight female preponderance. The common sites for intraoral BNSTs were parapharyngeal space followed by tongue, whereas mandible was the most common site for MNSTs. Most intraoral BNSTs were presented as slow-growing, painless mass or swelling, while MNSTs usually appeared as painful and invasive mass with discomfort. Surgical excision was preferred for intraoral BNSTs with excellent prognosis. Complete resection was indicated for intraoral MNST with dismal prognosis as evidenced by much recurrence, metastasis, and death.

CONCLUSION

Intraoral BNST and MNST are rare diseases which should not be ignored when intraoral painless or painful mass/swelling is found. Surgical excision is indicated for intraoral BNST with favorable outcomes. However, further investigations are warranted to optimize the treatment for intraoral MNST to improve its prognosis.

Tumour stem cells in schwannoma: A review

Schwannoma is a peripheral nerve tumour, accounting for 5% of benign soft tissue tumours, with vestibular schwannoma comprising 6% of all intracranial tumours. The tumour stem cell concept is rapidly gaining traction underscoring the understanding of tumourigenesis. It proposes a small subpopulation of primitive cells as the origin of the tumour and these cells account for treatment resistance, local recurrence and distant metastasis in malignant tumours. This review outlines the stem cell markers used to identify and characterise stem cells and progenitor cells in tumours and examines current evidence of the presence of tumour stem cells in schwannoma.

Treatment and survival differences across tumor sites in malignant peripheral nerve sheath tumors: a SEER database analysis and review of the literature

Background

Currently, literature is scarce on differences across all possible tumor sites in malignant peripheral nerve sheath tumors (MPNSTs). To determine differences in treatment and survival across tumor sites and assess possible predictors for survival, we used the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

MPNST cases were obtained from the SEER database. Tumor sites were recoded into: intracranial, spinal, head and neck (H&N), limbs, core (thorax/abdomen/pelvis), and unknown site of origin. Patient and tumor characteristics, treatment modalities, and survival were extracted. Overall survival (OS) was assessed using univariable and multivariable Cox regression hazard models. Kaplan-Meier survival curves were constructed per tumor site for OS and disease-specific survival (DSS).

Results

A total of 3267 MPNST patients were registered from 1973 to 2013; 167 intracranial (5.1%), 119 spinal (3.6%), 449 H&N (13.7%), 1022 limb (31.3%), 1307 core (40.0%), and 203 unknown (6.2%). The largest tumors were found in core sites (80.0 mm, interquartile range [IQR]: 60.0-115.0 mm) and the smallest were intracranial (37.4 mm, IQR: 17.3-43.5 mm). Intracranial tumors were least frequently resected (58.1%), whereas spinal tumors were most often resected (83.0%). Radiation was administered in 35.5% to 41.8%. Independent factors associated with decreased survival were: older age, male sex, black race, no surgery, partial resection, large tumor size, high tumor grade, H&N site, and core site (all P < .05). Intracranial and pediatric tumors show superior survival (both P < .05). Intracranial tumors show superior OS and DSS curves, whereas core tumors have the worst (P < .001).

Conclusion

Superior survival is seen in intracranial and pediatric MPNSTs. Core and H&N tumors have a worse prognosis.

CT, MRI, and 18F-FDG PET/CT findings of malignant peripheral nerve sheath tumor of the head and neck

Background Malignant peripheral nerve sheath tumor (MPNST) is a highly malignant tumor and rarely occurs in the head and neck. Purpose To describe the imaging features of MPNST of the head and neck. Material and Methods We retrospectively analyzed computed tomography (CT; n = 14), magnetic resonance imaging (MRI; n = 16), and ¹⁸F-FDG PET/CT (n = 5) imaging features of 18 MPNSTs of the head and neck in 17 patients. Special attention was paid to determine the nerve of origin from which the tumor might have arisen. Results All lesions were well-defined (n = 3) or ill-defined (n = 15) masses (mean, 6.1 cm). Lesions were at various locations but most commonly the neck (n = 8), followed by the intracranial cavity (n = 3), paranasal sinus (n = 2), and orbit (n = 2). The nerve of origin was inferred for 11 lesions: seven in the neck, two in the orbit, one in the cerebellopontine angle, and one on the parietal scalp. Attenuation, signal intensity, and enhancement pattern of the lesions on CT and MRI were non-specific. Necrosis/hemorrhage/cystic change within the lesion was considered to be present on images in 13 and bone change in nine. On ¹⁸F-FDG PET/CT images, all five lesions demonstrated various hypermetabolic foci with maximum standard uptake value (SUV_max) from 3.2 to 14.6 (mean, 7.16 ± 4.57). Conclusion MPNSTs can arise from various locations in the head and neck. Though non-specific, a mass with an ill-defined margin along the presumed course of the cranial nerves may aid the diagnosis of MPSNT in the head and neck.

A Clinicopathologic Study of Head and Neck Malignant Peripheral Nerve Sheath Tumors

Head and neck high grade malignant peripheral nerve sheath tumors (HN-MPNSTs) are rare highly aggressive soft tissue sarcomas that show overlapping morphologic and immunophenotypic features with melanoma and other high grade sarcomas, resulting in diagnostic challenges, particularly in sporadic settings. Recent discoveries have implicated loss of function mutations in the polycomb repressive complex 2 (PRC2) components, including EED or SUZ12 genes, as one of the leading pathogenetic mechanisms in high grade MPNST. MPNSTs with PRC2 loss are associated with complete loss of trimethylation at lysine 27 of histone H3 (H3K27me3), which emerged as a reliable immunohistochemical marker in the diagnosis of sporadic and radiation induced MPNST. As the diagnosis of MPNST in the HN is particularly challenging to distinguish from melanoma and other sarcoma types, we carried out a clinicopathologic analysis on HN-MPNST patients managed at our institution over a 20-year period (1997-2016), using the latest diagnostic criteria including H3K27me3 staining and other molecular investigations. The overall survival of HN-MPNST was compared with other HN soft tissue sarcomas. The diagnosis of HN-MPNST was confirmed in 13 patients (seven males and six females), with a mean age of 31 years; with 3 (23%) patients being of pediatric age. The most common site was the neck soft tissue (77%). Two-thirds of patients (n = 9) had stigmata of NF1, three had prior radiotherapy and only one developed a de novo MPNST. All except one tumor (86%) tested showed loss of H3K27me3 expression, including all non-NF1 patients. The 2 and 5-year DSS rates were 50 and 30%. The 2-year DFS rate was 21%. Adverse predictors on DSS included adult age (p = 0.011), prior-history of RT (p = 0.003) and recurrence (p = 0.003). Compared to other molecularly confirmed subsets of HN sarcomas (Ewing and Ewing-like sarcoma, rhabdomyosarcoma and synovial sarcoma), HN-MPNST had the worst overall survival (p < 0.0001). We conclude that HN-MPNSTs are highly aggressive sarcomas associated with an unfavorable outcome and the utility of H3K27me3 IHC stains in the evaluation of MPNST is a reliable ancillary diagnostic adjunct.

Clinicopathological features and prognosis of malignant peripheral nerve sheath tumor: a retrospective study of 159 cases from 1999 to 2016

Objective

To investigate the clinicopathological features and prognosis of malignant peripheral nerve sheath tumors (MPNST).

Results

A total of 159 patients with MPNST were enrolled in the study. The ratio of male to female was 1.04 to 1. The median age was 40 (range: 5–76) years at the time of diagnosis. The 3- and 5-year overall survival rates were 50.0% and 43.0%, respectively. The median follow-up period was 31.0 (range: 2.0–199.0) months. Multivariate analysis showed that AJCC stage and S-100 were independent factors affecting overall survival (p < 0.05 for both). 3- and 5-year tumor-free survival rates for 140 completely resected patients were 40.0% and 34.0%, respectively. Multivariate analysis showed that AJCC stage, S-100 and Ki67 staining were independent factors of tumor-free survival (p < 0.05 for all).

Materials and Methods

The clinical data of MPNST patients who were treated at Cancer Institute and Hospital, Chinese Academy of Medical Science from January 1999 to January 2016 was retrospectively reviewed.

Conclusions

MPSNT is a highly aggressive tumor with poor prognosis and this study may be useful for prognostic assessment and management decisions. This had been largest documented retrospective study of MPSNT among Chinese populations. Some characteristics were different from those of foreign populations which may suggest the specificity of Chinese patients.

Malignant peripheral nerve sheath tumors of the head and neck: Demographics, clinicopathologic features, management, and treatment outcomes

OBJECTIVES

To determine the epidemiology and prognostic indicators in patients with malignant peripheral nerve sheath tumors (MPNST) of the head and neck.

MATERIALS AND METHODS

The surveillance, epidemiology, and end results registry was reviewed for patients with head and neck MPNST from 1973 to 2011. Study variables included age, sex, race, tumor size, stage at presentation, and treatment modality.

RESULTS

There were 374 cases of head and neck MPNST identified. Mean age at diagnosis was 50.7 y ears; 60.2% of patients were male and 82.6% were white. After diagnosis, 38.8% of patients underwent surgery and radiation therapy and 48.1% underwent surgery alone. Kaplan-Meier analysis demonstrated overall (OS) and disease-specific survival (DSS) of 51% and 67% at 5 years. Multivariate Cox regression analysis showed that age (p=0.030), stage (p=0.002), surgery (p=0.037), and size (p<0.001) were predictors of OS, while stage (p<0.001) and size (p<0.001) were predictors of DSS. For stage I/II cancers, surgery (p=0.011) and size (p=0.010) were predictors of OS, and size (p=0.001) predicted DSS. For stage III/IV cancers, both radiotherapy (p=0.024, p=0.009) and size (p=0.001, p=0.001) predicted OS and DSS. For tumors ⩽5 cm, stage (p=0.031) predicted DSS. For tumors >5 cm, male gender (p=0.005), stage (p=0.001), surgery (p=0.003), and radiotherapy (p=0.050) were determinants of OS, and male gender (p=0.022), stage (p<0.001), and radiotherapy (p=0.002) were determinants of DSS.

CONCLUSION

Surgical resection confers survival benefit in patients with early stage MPNST, while radiotherapy improves survival in cases with metastatic disease. Surgery and radiotherapy are prognostically important in patients with tumors >5 cm.

Comparative Analysis of Head and Neck and Non–Head and Neck Malignant Peripheral Nerve Sheath Tumors

Objectives

Malignant peripheral nerve sheath tumors (MPNSTs) are a group of tumors that arise from peripheral nerves or from the various elements of the nerve sheath, including Schwann cells and perineural fibroblasts. Head and neck MPNSTs (HN-MPNSTs) are rare, accounting for 8% to 16% of all soft tissue sarcomas. This study analyzes the demographic, clinicopathologic, and survival characteristics of HN-MPNSTs and establishes comparisons with MPNSTs at other body sites (other-MPNSTs).

Study Design

Analysis of population-based tumor registry.

Setting

Academic medical center.

Subjects and Methods

The SEER database (Surveillance, Epidemiology, and End Results; 1973-2012) was queried for HN-MPNSTs (324 cases) and other-MPNSTs (1680 cases). Data were analyzed comparatively with respect to various demographic and clinicopathologic factors. Disease-specific survival was analyzed with the Kaplan-Meier model.

Results

Mean age at diagnosis for HN-MPNST was 49.1 years, compared with 46.1 years for other-MPNSTs ( P = .0169). There was a sex predilection for males in HN-MPNSTs (60.2%) versus a female predilection for other-MPNSTs (54.2%; P < .0001). Average tumor size for HN-MPNSTs was 4.9 cm, compared with 8.7 cm for other-MPNSTs ( P < .0001). HN-MPNSTs were more commonly of low histologic grade types, whereas other-MPNSTs were mostly of high histologic grade ( P = .0073). HN-MPNSTs had a higher 5-year disease-specific survival than other-MPNSTs (65.1% vs 57.4%; P = .0209).

Conclusions

HN-MPNSTs are rare entities. This study represents the largest series of HN-MPNSTs to date. Although HN-MPNSTs and other-MPNSTs share a common histology, there are important clinical differences between the 2 groups.

Malignant peripheral nerve sheath tumor (MPNST) in the spine: a retrospective analysis of clinical and molecular prognostic factors

Spinal malignant peripheral nerve sheath tumors (MPNSTs) are relatively rare. There is little information published in the literature regarding this subject. The aim of this retrospective study was to evaluate factors that may affect the outcomes of patients with spinal MPNSTs by reviewing 43 patients with spinal MPNST who were treated in our hospital between 2001 and 2012. Univariate and multivariate analyses were performed to identify prognostic variables relative to patient and tumor characteristics, treatment modality and molecules. All 43 MPNST patients (25 men and 18 women; median age 49 years) underwent surgical resection, of whom 15 patients also underwent postoperative radiotherapy. Local recurrence was found in 21 (48.8 %) patients. Twenty-two (51.2 %) patients died during the follow-up periods with a median survival time of 49 months. The 5-year recurrence and survival rate was 53 and 44 % respectively. The statistical analyses suggested that high-grade malignancy and osteolytic destruction were closely associated with recurrence and death. A total of 38 cases accepted postoperative immunohistochemisty examine. S-100 was identified as an independent factor related to both recurrence and survival, adjusting for clinical factors. In conclusion, we confirmed that malignant grade and osteolytic destruction were the two independent factors for both recurrence and survival, while patients with S-100 protein negative had a higher recurrence rate and a lower survival rate.