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

Malignant Transformation of Plexiform Neurofibroma Due to Neglected Giant Soft Tissue Swelling of the Back: A Case Report

Neurofibromatosis type 1 can be severe and associated with malignant transformation. Proper follow-up and monitoring are very important in preventing the malignant transformation of neurofibromatosis. We encountered a case of malignant transformation of plexiform neurofibroma into neurofibrosarcoma (also known as malignant peripheral nerve sheath tumor). She had been presenting with a large mass on her back for a few years, which was also associated with an ulcer. She underwent a wide-excision biopsy of her back, and the histopathology examination (HPE) came back with a malignant peripheral nerve sheath tumor. This case concludes that any patient with a known case of neurofibromatosis should undergo follow-up to detect any malignant transformation of the disease. Early detection of the malignant transformation of neurofibromatosis can help prevent the disease's progression. The main treatment is surgical resection; however, the risk of local recurrence is higher, especially in patients with neurofibromatosis type 1.

Integrated Epigenetic and Transcriptomic Analysis Identifies Interleukin 17 DNA Methylation Signature of Malignant Peripheral Nerve Sheath Tumor Progression and Metastasis

PURPOSE

Sarcomas are a complex group of highly aggressive and metastatic tumors with over 100 distinct subtypes. Because of their diversity and rarity, it is challenging to generate multisarcoma signatures that are predictive of patient outcomes.

MATERIALS AND METHODS

Here, we identify a DNA methylation signature for progression and metastasis of numerous sarcoma subtypes using multiple epigenetic and genomic patient data sets. Malignant Peripheral Nerve Sheath Tumors (MPNSTs) are highly metastatic sarcomas with frequent loss of the histone methyltransferase, PRC2. Loss of PRC2 is associated with MPNST metastasis and plays a critical noncanonical role in DNA methylation.

RESULTS

We found that over 900 5'-C-phosphate-G-3' (CpGs) were hypermethylated in MPNSTs with PRC2 loss. Furthermore, we identified eight differentially methylated CpGs in the IL17D/RD family that correlate with the progression and metastasis of MPNSTs in two independent patient data sets. Similar trends were identified in other sarcoma subtypes, including osteosarcoma, rhabdomyosarcoma, and synovial sarcoma. Analysis of scRNAseq data sets determined that IL17D/RD expression occurs in both the tumor cells and the surrounding stromal populations.

CONCLUSION

These results might have broad implications for the clinical management and surveillance of sarcoma.

Local recurrence in malignant peripheral nerve sheath tumours: multicentre cohort study

BACKGROUND

Malignant peripheral nerve sheath tumours (MPNSTs) have high local recurrence (LR) rates. Literature varies on LR risk factors and treatment. This study aimed to elucidate treatment options and risk factors for first and second LRs (LR1 and LR2) in a large multicentre cohort.

METHOD

Surgically treated primary MPNSTs between 1988 and 2019 in the MONACO multicentre cohort were included. Cox regression analysed LR1 and LR2 risk factors and overall survival (OS) after LR1. Treatment of LR1 and LR2 was evaluated.

RESULTS

Among 507 patients, 28% developed LR1. Median follow-up was 66.9 months, and for survivors 111.1 months. Independent LR1 risk factors included high-grade tumours (HR 2.63; 95% c.i. 1.15 to 5.99), microscopically positive margins (HR 2.19; 95% c.i. 1.51 to 3.16) and large tumour size (HR 2.14; 95% c.i. 1.21 to 3.78). Perioperative radiotherapy (HR 0.62; 95% c.i. 0.43 to 0.89) reduced the risk. LR1 patients had poorer OS. Synchronous metastasis worsened OS (HR 1.79; 95% c.i. 1.02 to 3.14) post-LR1, while surgically treated LR was associated with better OS (HR 0.38; 95% c.i. 0.22 to 0.64) compared to non-surgical cases. Two-year survival after surgical treatment was 71% (95% c.i. 63 to 82%) versus 28% (95% c.i. 18 to 44%) for non-surgical LR1 patients. Most LR1 (75.4%) and LR2 (73.7%) patients received curative-intent treatment, often surgery alone (64.9% versus 47.4%). Radiotherapy combined with surgery was given to 11.3% of LR1 and 7.9% of LR2 patients.

CONCLUSION

Large, high-grade MPNSTs with R1 resections are at higher LR1 risk, potentially reduced by radiotherapy. Surgically treated recurrences may provide improved survival in highly selected cases.

Survival outcomes of malignant peripheral nerve sheath tumors (MPNSTs) with and without neurofibromatosis type I (NF1): a meta-analysis

INTRODUCTION

Malignant peripheral nerve sheath tumors (MPNSTs) are malignancies that demonstrate nerve sheath differentiation in the peripheral nervous system. They can occur sporadically or be associated with neurofibromatosis type 1 (NF1), an autosomal dominant neurocutaneous disorder, with up to 13% of patients developing MPNSTs in their lifetimes. Previous studies have suggested conflicting findings regarding the prognosis of NF1 for patients with MPNSTs. The elucidation of NF1 as an independent prognostic factor on mortality has implications for clinical management. We aim to investigate the role of NF1 status as an independent prognostic factor of overall survival (OS) and disease-specific survival (DSS) in MPNSTs.

METHODS

An electronic literature search of PubMed and MEDLINE was performed on studies reporting OS or DSS outcomes of MPNSTs with and without NF1. A grey literature search by reviewing bibliographies of included studies and review articles was performed to find pertinent studies. Data was extracted and assessed in accordance with the PRISMA guidelines. A meta-analysis was performed to calculate hazard ratios (HRs) using a random-effects model. The primary and secondary outcomes were all-cause and disease-specific mortality, respectively, with NF1 as an independent prognostic factor of interest.

RESULTS

A total of 59 retrospective studies involving 3602 patients fulfilled the inclusion criteria for OS analysis, and 23 studies involving 704 MPNST patients were included to evaluate DSS outcomes. There was a significant increase in the hazard of all-cause mortality (HR 1.63, 95% CI 1.45 to 1.84) and disease-specific mortality (HR 1.52, 95% CI 1.24 to 1.88) among NF1 as compared to sporadic cases. Subgroup analyses and meta-regression showed that this result was consistent regardless of the quality of the study and year of publication.

CONCLUSION

NF1 is associated with a substantially higher risk of all-cause and disease-specific mortality. This finding suggests that closer surveillance is required for NF1 patients at risk of developing MPNSTs.

The role of radiotherapy in the management of malignant peripheral nerve sheath tumors: a single-center retrospective cohort study

PURPOSE

This study sought to investigate the role of radiotherapy (RT) in addition to surgery for oncological outcomes in patients with malignant peripheral nerve sheath tumors (MPNST).

METHODS

In this single-center, retrospective cohort study, histopathologically confirmed MPNST were analyzed. Local control (LC), overall survival (OS), and distant metastasis-free survival (DMFS) were assessed using the Kaplan-Meier estimator. Multivariable Cox regression analysis was performed to identify factors associated with LC, OS, and DMFS.

RESULTS

We included 57 patients with a median follow-up of 20.0 months. Most MPNSTs were located deeply (87.5%), were larger than 5 cm (55.8%), and had high-grade histology (78.7%). Seventeen patients received surgery only, and 25 patients received surgery and pre- or postoperative RT. Median LC, OS, and DMFS after surgery only were 8.7, 25.5, and 22.0 months; after surgery with RT, the median LC was not reached, while the median OS and DMFS were 111.5 and 69.9 months. Multivariable Cox regression of LC revealed a negative influence of patients presenting with local disease recurrence compared to patients presenting with an initial primary diagnosis of localized MPNST (hazard ratio: 8.86, p = 0.003).

CONCLUSIONS

The addition of RT to wide surgical excision appears to have a beneficial effect on LC. Local disease recurrence at presentation is an adverse prognostic factor for developing subsequent local recurrences. Future clinical and translational studies are warranted to identify molecular targets and find effective perioperative combination therapies with RT to improve patient outcomes.

Malignant peripheral nerve sheath tumor in the pelvis: a case report

BACKGROUND

Malignant peripheral nerve sheath tumors (MPNSTs) are malignancies that arise or differentiate from or infiltrate peripheral nerves and account for approximately 5% of soft-tissue malignancies. Approximately half of MPNSTs develop in patients with neurofibromatosis type 1 (NF1), a hereditary disease. MPNSTs occur mainly in the trunk, proximal extremities, and neck, but can on rare occasion arise in or near the gastrointestinal tract, and intestinal complications have been reported. We describe herein a case with resection of an MPNST arising in the pelvic region.

CASE PRESENTATION

A 51-year-old woman had undergone repeated resections for systemic neurofibrosis associated with NF1. This time, a pelvic tumor was noted on follow-up positron emission tomography computed tomography (CT). She presented with slowly progressive radiating pain in the lower extremities and was referred to our hospital for tumor resection. Contrast-enhanced CT showed a 75 × 58-mm mass in the right greater sciatic foramen directly below a 24 × 28-mm mass. Open pelvic tumor resection was performed for pelvic neurofibroma. The obturator nerve was identified lateral to the main tumor and the sciatic nerve was identified dorsally, then dissection was performed. The closed nerve was spared, while the sciatic nerve was partially dissected and the two tumors were removed. Both tumors were elastic and hard. Pathologic findings were MPNST for the large specimen and neurofibroma with atypia for the small specimen. The patient developed temporary postoperative ileus, but is generally doing well and is currently free of recurrence or radiating pain. The patient is at high risk of recurrence and close monitoring should be continued.

CONCLUSIONS

We encountered a rare case of MPNST. Due to the high risk of recurrence, surgery with adequate margins was performed, with a requirement for appropriate follow-up.

Clinicopathological Assessment of Cancer/Testis Antigens NY-ESO-1 and MAGE-A4 in Highly Aggressive Soft Tissue Sarcomas

We aimed to investigate the clinical significance of the expression of NY-ESO-1 and MAGE-A4 in soft tissue sarcoma (STS). Immunostaining for NY-ESO-1, MAGE-A4, and Ki67 was performed using pathological specimens harvested from 10 undifferentiated pleomorphic sarcoma (UPS), nine myxofibrosarcoma (MFS), and three malignant peripheral nerve sheath tumor (MPNST) patients treated at our hospital. We examined the correlation of NY-ESO-1 and MAGE-A4 expression levels with tumor size, histological grade, and SUVmax values. Positive cell rates of various markers were also compared between patients in remission and those who were not in remission. The rates of cases positive for NY-ESO, MAGE-A4, and Ki67 were 50%, 63.6%, and 90.9%, respectively. The average rates of cells positive for NY-ESO, MAGE-A4, and Ki67 in all STS types were 18.2%, 39.4%, and 16.8%, respectively. A positive correlation was observed between rates of cells positive for NY-ESO-1 and MAGE-A4 and between NY-ESO-1 and MAGE-A4 expression levels and clinical features. There was no significant difference in the positive cell rate of NY-ESO-1 or MAGE-A4 between remission and non-remission cases. Our results suggest that NY-ESO-1 and MAGE-A4 expression may be useful for the diagnosis and prognostication of UPS, MFS, and MPNST.

Clinical Outcomes and Prognostic Factors for Patients with Malignant Peripheral Nerve Sheath Tumour

Introduction

Few studies have described the characteristics and prognostic factors of patients with malignant peripheral nerve sheath tumour (MPNST). In this study, we retrospectively investigated the clinicopathological features, clinical outcomes, and prognostic factors of these patients. Patients and Methods. We recruited patients with MPNST who were treated at our institutions from 1991 to 2020. We collected and statistically analysed information on patient-, tumour-, and treatment-related factors. The median follow-up period was 61 months (range, 1-335.8 months).

Results

A total of 60 patients (31 males, 29 females) with a median age of 55 years (range, 8-84 years) at initial diagnosis were included. The median tumour size was 7 cm (range, 1.6-30 cm) in the greatest dimension. The 5-year overall survival (OS) rate of all patients was 69.5%. Univariate analysis revealed that large-sized tumour, metastasis at diagnosis, and no surgery of the primary tumour were significantly associated with patients with worse OS. Multivariate analysis identified surgery of the primary tumour as an independent prognostic factor for improved OS. Among patients with localised disease at diagnosis who underwent surgery of the primary tumour at our institutions, the 5-year OS, local recurrence-free survival (LRFS), and metastasis-free survival (MFS) rates were 81.1%, 78.2%, and 70.3%, respectively. Univariate analysis revealed that positive surgical margin was significantly correlated with unfavourable OS and LRFS, and high grade was a poor prognostic indicator for MFS.

Conclusion

Complete surgical resection with negative surgical margins is necessary for a successful MPNST treatment. Multidisciplinary management of MPNST with aggressive features is important for optimising patient outcomes.

Surgical management and oncological outcome of non-squamous cell carcinoma of the larynx: a bicentric study

Purpose

Non-squamous cell carcinoma (non-SCC) accounts for about 5% of laryngeal malignancies. Survival data are limited, and consensus on management principles is lacking. The present study reviews our experience in the surgical treatment of non-metastatic non-SCC of the larynx and compares oncological and functional outcomes in a cohort of patients affected by traditional SCC.

Methods

We collected data on 592 patients affected by laryngeal neoplasms. Univariate and multivariable survival analyses were performed using Cox proportional-hazards models; survival estimates were reported by hazard ratios (HR) with 95% confidence intervals (CI), and survival curves were established with the Kaplan–Meier method.

Results

We identified 326 patients affected by untreated SCC, while 21 had non-SCC histotypes. The non-SCC cohort was composed of 5 soft tissue sarcomas, 8 chondrosarcomas, 2 adenoid cystic carcinomas, 2 neuroendocrine carcinomas, 2 solitary fibrous tumors, 1 Kaposi’s sarcoma, and 1 malignant peripheral nerve sheath tumor. Overall survival and disease-specific survival were not significantly different according to histology (p = 0.6 and p = 0.349, respectively). The non-SCC group showed an increased risk of recurrence (HR 5.87; CI₉₅ 2.15–16.06; p < 0.001). Nonetheless, no significant difference (p = 0.31) was found at multivariable analysis between the two groups in total laryngectomy-free survival with an organ preservation rate over 5 years of 81% for the non-SCC histologies.

Conclusion

Non-SCC is a broad spectrum pathology, but generalized laryngeal surgical management principles are still feasible and it is possible to identify patients amenable to conservative surgical treatment without affecting survival.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00405-021-07076-x.

Parotid Neurogenic Tumors: MPNST Sarcoma to Schwannoma-Review of Literature and Guidelines in Management

Objective

To delineate a distinct clinical, pathological, cytoimmunohistochemical distinguishing features of extracranial parotid neurogenic tumors. Pleomorphic adenoma, the most common parotid neoplasm by itself can mimic a neurogenic tumor, i.e., schwannoma. We have reported such rare entity in earlier publications. This is a systematic review with a case discussion of the third only documented malignant peripheral nerve sheath tumor (MPNST) arising in the parotid in a noncontiguous fashion. We review the management, diagnostic immunohistochemistry of this low-grade sarcoma, which has not been documented thus far.

Purpose

Significant diagnostic and management pitfalls may occur even with fine-needle aspiration or biopsy, as they will not be ideal in diagnosis of parotid neurogenic neoplasms preoperatively. Ultrasound as well as magnetic resonance imaging may not offer a specific facial nerve course in association to the neoplastic lesion. Majority of the neurogenic tumors can be misdiagnosed and hence, improperly managed leading to facial nerve injury and tumor morbidity. Due to the lack of ideal diagnostic modality and morbidity of facial nerve injury, a thorough review of differential diagnosis inclusive of neurogenic tumors of the parotid is to be considered in indications of surgical approaches. We retrospectively review successful resection with preservation of facial nerve function in our parotid neurogenic tumors.

Conclusion

The objective of this paper is to review the guidelines and treatment planning of parotid neurogenic tumors.

Surgical Management of Symptomatic Lumbar, Sacral, and Lumbosacral Plexus Tumors: a Peripheral Nerve Unit Experience

OBJECTIVE

Data concerning the surgical treatment of lumbosacral plexus tumors (LSPTs) is scarce. This study aims to present our experience with a series of 19 patients surgically treated for symptomatic LSPTs at our institution.

METHODS

This is a retrospective study of 19 patients surgically treated for symptomatic LSPTs from 2011 to 2019. Clinical data were retrieved from medical records and consisted of age, gender, clinical presentation, location of the lesion, surgical approach, final histopathologic diagnosis, follow-up time, outcomes, and complications.

RESULTS

Nineteen surgical procedures were conducted. Thirteen patients were female and six, male. The median age of patients was 45 years (range 20 to 63 years). No patients harbored genetic syndromes. Surgical treatment appears to be correlated to the reduction of pain in patients with peripheral nerve sheath tumors (PNSTs), as assessed by visual analog scale (VAS). Sixteen patients did not present with new-onset deficits during follow-up (84.2%), two of whom recovered from their preoperative deficit. Four patients presented with postoperative weakness. The histopathological diagnoses were 11 schwannomas, four neurofibromas, three metastases, and one lymphoma.

CONCLUSIONS

LSPTs are rare. When surgical treatment is indicated, it usually requires multidisciplinary management. Surgery appears to be effective concerning the reduction of pain in PNSTs and may also recover neurological deficits. Iatrogenic neurological deficits are an evident risk, such that intraoperative multimodal monitoring should always be performed if available. In lesions involving the sacral plexus, we found it to be indispensable.

Malignant Peripheral Nerve Sheath Tumor in an Army Reservist With Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is an autosomal dominant condition affecting 1 in 3,500 people resulting from an NF1 gene mutation that encodes the nonfunctional protein neurofibromin mutant. Neurofibromin is a negative regulator of RAS signaling involved in cell survival and proliferation. NF1 typically presents at birth or in early childhood with multiple light brown (café au lait) spots and axillary freckling. With age, patients may develop scattered neurofibromas as well as additional neurological and malignant abnormalities. Additionally, the nonfunctional protein neurofibromin mutant may be involved in the pathogenesis of peripheral malignant nerve sheath tumors, which is a rare and life-threatening complication of NF1. While a disqualifying condition for military duty, it may not initially be clinically apparent until complications develop. Here, we present a case of malignant peripheral sheath in an U.S. Army African American reservist with NF1 in whom cutaneous manifestations of NF1 such as café au lait spots and axillary freckling were not identified on the initial military entrance processing examination.

Diagnostic Accuracy of MRI for the Detection of Malignant Peripheral Nerve Sheath Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE. This systematic review and meta-analysis evaluates the diagnostic accuracy of MRI for differentiating malignant (MPNSTs) from benign peripheral nerve sheath tumors (BPNSTs). MATERIALS AND METHODS. A systematic review of MEDLINE, Embase, Scopus, the Cochrane Library, and the gray literature from inception to December 2019 was performed. Original articles that involved at least 10 patients and that evaluated the accuracy of MRI for detecting MPNSTs were included. Two reviewers independently extracted clinical and radiologic data from included articles to calculate sensitivity, specificity, PPV, NPV, and accuracy. A meta-analysis was performed using a bivariate mixed-effects regression model. Risk of bias was evaluated using QUADAS-2. RESULTS. Fifteen studies involving 798 lesions (252 MPNSTs and 546 BPNSTs) were included in the analysis. Pooled and weighted sensitivity, specificity, and AUC values for MRI in detecting MPNSTs were 68% (95% CI, 52-80%), 93% (95% CI, 85-97%), and 0.89 (95% CI, 0.86-0.92) when using feature combination and 88% (95% CI, 74-95%), 94% (95% CI, 89-96%), and 0.97 (95% CI, 0.95-0.98) using diffusion restriction with or without feature combination. Subgroup analysis, such as patients with neurofibromatosis type 1 (NF1) versus those without NF1, could not be performed because of insufficient data. Risk of bias was predominantly high or unclear for patient selection, mixed for index test, low for reference standard, and unclear for flow and timing. CONCLUSION. Combining features such as diffusion restriction optimizes the diagnostic accuracy of MRI for detecting MPNSTs. However, limitations in the literature, including variability and risk of bias, necessitate additional methodologically rigorous studies to allow subgroup analysis and further evaluate the combination of clinical and MRI features for MPNST diagnosis.

Prognostic Significance of Immunohistochemical Markers and Genetic Alterations in Malignant Peripheral Nerve Sheath Tumors: A Systematic Review

Background

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas with dismal prognosis. Pathological and genetic markers may predict more aggressive behavior in MPNSTs but have uncommonly been investigated, and few are used in daily practice. This study reviews the prognostic value of immunohistochemical markers and genetic alterations in MPNST.

Methods

A systematic search was performed in PubMed and Embase databases according to the PRISMA guidelines. Search terms related to ‘MPNST’ and ‘prognostic’ were used. Studies investigating the association of immunohistochemical markers or genetic alterations with prognosis were included. Qualitative synthesis was performed on all studies. A distinction was made between univariable and multivariable associations.

Results

Forty-six studies were included after full-text screening. Sixty-seven different immunohistochemical markers were investigated. Absence of S100 and H3K27me3 and high Ki67 and p53 staining was most commonly independently associated with worse survival and disease-free survival. Several genetic alterations were investigated as well with varying association to survival. TP53, CDK4, RASSF1A alterations were independently associated with worse survival, as well as changes in chromosomal length in Xp, 10q, and 16p.

Conclusions

MPNSTs harbor complex and heterogeneous biology. Immunohistochemical markers and genetic alterations have variable prognostic value. Absence of S100 and H3K27me3 and increased Ki67 can be of prognostic value. Alterations in TP53 or increase in p53 staining may distinguish MPNSTs with worse outcomes. Genetic alterations and staining of other cell cycle regulatory and Ras pathway proteins may also help stratifying patients with worse outcomes. A combination of markers can increase the prognostic value.

Histopathologic findings in malignant peripheral nerve sheath tumor predict response to radiotherapy and overall survival

Background

Malignant peripheral nerve sheath tumor (MPNST) is an aggressive and poorly understood malignant neoplasm. Even in the setting of multimodal therapy, the clinical course of MPNST is frequently marked by metastatic conversion and poor overall prognosis, with optimal treatment paradigms for this rare tumor unknown.

Methods

We reviewed the medical records and histopathology of 54 consecutive patients who were treated at University of California San Francisco between 1990 and 2018.

Results

Our cohort consisted of 24 male and 30 female patients (median age 38 years). Fédération Nationale des Centres de Lutte Contre Le Cancer (FNCLCC) sarcoma grading criteria segregated patients into groups with differences in overall survival (OS) (P = .02). Increasing Ki-67 labeling index was associated with poor OS (hazard ratio [HR] 1.36 per 10%, P = .0002). Unsupervised hierarchical clustering-based immunohistochemical staining patterns identified 2 subgroups of tumors with differences in H3K27me3, Neurofibromin, S100, SOX10, p16, and EGFR immunoreactivity. In our cohort, cluster status was associated with improved locoregional failure-free rate (P = .004) in response to radiation.

Conclusions

Our results lend support to the FNCLCC sarcoma grading criteria as a prognostic scheme for MPNST, although few cases of grade 1 were included. Further, we identify increased Ki-67 labeling as a strong predictor of poor OS from MPNST. Finally, we identify a subset of MPNSTs with a predictive immunohistochemical profile that has improved local control with adjuvant radiotherapy. These data provide insights into the grading and therapy for patients with MPNST, although further studies are needed for independent validation.

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.

Malignant peripheral nerve sheath tumors - Outcomes and prognostic factors based on the reference center experience

INTRODUCTION

Malignant peripheral nerve sheath tumor (MPNST) accounts for about 5% of soft tissue sarcomas. It can occur as sporadic diseases or can be associated with type 1 neurofibromatosis. MPNST is usually associated with poor prognosis, mostly due to their aggressive behavior, high metastatic potential, and resistance to chemotherapy. Our study aimed to determine treatment outcomes and associated prognostic factors in a large cohort of patients with MPNSTs treated at the reference sarcoma center.

METHODS

239 consecutive patients (114 women and 125 men) diagnosed with MPNST between March 1998 and March 2018 who were treated with surgery with curative intent in the reference sarcoma center were included in the retrospective analysis.

RESULTS

The mean age at diagnosis was 51 years (range 15-86). 28 (11.7%) patients had neurofibromatosis type 1 associated tumors (NF1 positive). Median OS was 126.5 months and 5-year survival rate was 61.9% in the group treated with curative intent. Median DFS, LRFS and DMFS were 91.6, 126.5 and 126.5 months, respectively. We identified tumor size, high tumor grade and positive surgical margins as independent negative predictors of DFS, LRFS, DMFS and OS.

CONCLUSIONS

High-quality surgery remains a gold standard of MPNST treatment. High grade, size and quality of surgery are significant independent prognostic factors for overall survival. There is an unmet need for improvement, especially regarding the perioperative treatment and treatment of metastatic disease. Future studies on the biology of MPNST would lead to the development of novel treatment options and improvement of treatment outcomes.

Neurofibromatosis-associated malignant peripheral nerve sheath tumors in children have a worse prognosis: A nationwide cohort study

BACKGROUND

Malignant peripheral nerve sheath tumors (MPNST) are rare and aggressive non-rhabdomyoblastic soft-tissue sarcomas (NRSTS) in children. This study set out to investigate clinical presentation, treatment modalities, and factors associated with survival in pediatric MPNST using Dutch nationwide databases.

METHODS

Data were obtained from the Netherlands Cancer Registry (NCR) and the Dutch Pathology Database (PALGA) from 1989 to 2017. All primary MPNSTs were collected. Demographic differences were analyzed between adult and pediatric (age ≤18 years) MPNST. In children, demographic and treatment differences between neurofibromatosis type 1 (NF1) and non-NF1 were analyzed. A Cox proportional hazard model was constructed for localized pediatric MPNSTs.

RESULTS

A total of 70/784 MPNST patients were children (37.1% NF1). Children did not present differently from adults. In NF1 children, tumor size was more commonly large (> 5 cm, 92.3% vs 59.1%). Localized disease was primarily resected in 90.6%, and radiotherapy was administered in 37.5%. Non-NF1 children tended to receive chemotherapy more commonly (39.5% vs 26.9%). Overall, estimated five-year survival rates of localized NF1-MPNST was 52.4% (SE: 10.1%) compared with 75.8% (SE: 7.1%) in non-NF1 patients. The multivariate model showed worse survival in NF1 patients (HR: 2.98; 95% CI, 1.17-7.60, P = 0.02) and increased survival in patients diagnosed after 2005 (HR: 0.20; 95% CI, 0.06-0.69, P = 0.01). No treatment factors were independently associated with survival.

CONCLUSION

Pediatric MPNSTs have presentations similar to adult MPNSTs. In children, NF1 patients present with larger tumors, but are treated similarly to non-NF1 MPNSTs. In localized pediatric MPNST, NF1 is associated with worse survival. Promisingly, survival has increased for pediatric MPNSTs after 2005.

Integrative Analysis Identifies Candidate Tumor Microenvironment and Intracellular Signaling Pathways that Define Tumor Heterogeneity in NF1

Neurofibromatosis type 1 (NF1) is a monogenic syndrome that gives rise to numerous symptoms including cognitive impairment, skeletal abnormalities, and growth of benign nerve sheath tumors. Nearly all NF1 patients develop cutaneous neurofibromas (cNFs), which occur on the skin surface, whereas 40-60% of patients develop plexiform neurofibromas (pNFs), which are deeply embedded in the peripheral nerves. Patients with pNFs have a ~10% lifetime chance of these tumors becoming malignant peripheral nerve sheath tumors (MPNSTs). These tumors have a severe prognosis and few treatment options other than surgery. Given the lack of therapeutic options available to patients with these tumors, identification of druggable pathways or other key molecular features could aid ongoing therapeutic discovery studies. In this work, we used statistical and machine learning methods to analyze 77 NF1 tumors with genomic data to characterize key signaling pathways that distinguish these tumors and identify candidates for drug development. We identified subsets of latent gene expression variables that may be important in the identification and etiology of cNFs, pNFs, other neurofibromas, and MPNSTs. Furthermore, we characterized the association between these latent variables and genetic variants, immune deconvolution predictions, and protein activity predictions.

Neurofibromatosis 1 French national guidelines based on an extensive literature review since 1966

Neurofibromatosis type 1 is a relatively common genetic disease, with a prevalence ranging between 1/3000 and 1/6000 people worldwide. The disease affects multiple systems with cutaneous, neurologic, and orthopedic as major manifestations which lead to significant morbidity or mortality. Indeed, NF1 patients are at an increased risk of malignancy and have a life expectancy about 10-15 years shorter than the general population. The mainstay of management of NF1 is a patient-centered longitudinal care with age-specific monitoring of clinical manifestations, aiming at the early recognition and symptomatic treatment of complications as they occur. Protocole national de diagnostic et de soins (PNDS) are mandatory French clinical practice guidelines for rare diseases required by the French national plan for rare diseases. Their purpose is to provide health care professionals with guidance regarding the optimal diagnostic and therapeutic management of patients affected with a rare disease; and thus, harmonizing their management nationwide. PNDS are usually developed through a critical literature review and a multidisciplinary expert consensus. The purpose of this article is to present the French guidelines on NF1, making them even more available to the international medical community. We further dwelled on the emerging new evidence that might have therapeutic potential or a strong impact on NF1 management in the coming feature. Given the complexity of the disease, the management of children and adults with NF1 entails the full complement healthcare providers and communication among the various specialties.

Mixed malignant peripheral nerve sheath tumor in the inguinal region: a case report

Malignant peripheral nerve sheath tumor (MPNST) is a rare malignant soft tissue tumor that accounts for approximately 5% of all soft tissue sarcomas. This tumor originates from the peripheral nerves and occurs mainly in the limbs, head and neck, and spine. As a more aggressive tumor, it has higher recurrence and metastasis rates, and patient prognosis is poor. MPNST has a variety of histologic subtypes such as classic MPNST and epithelioid malignant peripheral nerve sheath tumors (EMPNSTs). Due to the diversity of histologic types, these tumors have a high histologic similarity to other benign and malignant soft tissue tumors. Due to the lack of specific diagnostic criteria, pathologic diagnosis is extremely difficult, since these tumors should be differentiated from other sarcomas according to the site of tumor occurrence and morphologic characteristics, which can be determined using immunohistochemical staining. The specific pathogenesis of MPNST is not well understood. Studies have shown that approximately 50% of MPNSTs are closely related to neurofibromatosis I (NF1), while other causes of these tumors include radiotherapy. Herein, we report the first case of a mixed tumor composed of classic MPNST and EMPNST elements in the inguinal region.

Peripheral nerve tumours: A 66-case retrospective study

BACKGROUND/OBJECTIVES

Peripheral nerve tumours (PNT) are rare lesions that are generally categorised as soft tissue tumours, so they are usually managed by a range of surgical disciplines such as plastic, orthopaedic and trauma surgery, dermatology, general surgery and neurosurgery. Appropriate knowledge of the therapeutic indication and surgical management are essential in order to avoid neurological deficit.

MATERIALS AND METHODS

This is a retrospective study of 66 tumour lesions in 64 patients, acquired from the joint experience of 2surgical teams specialised in peripheral nerve surgery.

RESULTS

The most common location was the lower limb and upper limb with 48 tumour lesions. The most common pathological diagnosis was Schwannoma, accounting for 51.5%. Complete tumour resection was achieved in 81.8% of the lesions and always with neurophysiological stimulation and/or monitoring. The most common postsurgical complication was neuropathic pain and/or a transient sensory disorder in 15% of surgeries, with only one persistent motor deficit appearing in 2cases that required nerve graft reconstruction.

CONCLUSIONS

Although the therapeutic management of benign tumours such as Schwannomas can be considered to be relatively simple thanks to the application of the basic concepts of peripheral nerve microsurgery, malignant tumors, despite being very rare, require multidisciplinary management. The option of pre-surgical biopsy remains a controversial issue and no consensus has been reached among the different authors. In our opinion, percutaneous biopsy is not necessary in most cases.

Neurofibromatosis type 1-associated malignant peripheral nerve sheath tumour carcinomatous pleurisy: an autopsy case

A 57-year-old man with neurofibromatosis type 1 (NF-1) and intrathoracic meningoceles was admitted to hospital after presenting with neck pain and progressive dyspnoea. On admission, a chest computed tomography scan demonstrated right pleural effusion, neck tumour, intrathoracic meningoceles, and rib metastasis. The myelography showed no transportation between the intrathoracic meningoceles and pleural cavity. As a result, these radiological finding indicated the potential for malignant transformation. The appearance of the right pleural effusion was bloody and had no malignant cells. We biopsied the neck tumour, and the tissue showed glass-like materials but no malignant cells. At 1 month after admission, he developed bladder-rectal disorder, syndrome of inappropriate secretion of antidiuretic hormone, and paralysis of both legs and later died. An autopsy demonstrated glass-like material in the neck tumour, which was surrounded by malignant cells. NF-1 appears to have progressed to a malignant peripheral nerve sheath tumour in this patient.

Arm malignant peripheral nerve sheath tumour: a rare clinical presentation

Soft tissue sarcomas account for about 1% of malignant tumours. More than 50 subtypes of these tumours have been described with some being extremely rare, namely malignant peripheral nerve sheath tumours (MPNST). The authors present a case of a man aged 81 years with a medical history of an adenocarcinoma of the rectum, which was referred to our clinic due to a growing painless mass on the right arm. An MRI showed a well-delimited encapsulated mass involving the long head of the biceps muscle. Biopsy findings revealed a spindle cell tumour with cytonuclear pleomorphism. The patient underwent wide tumour excision and was successfully reconstructed with a latissimus dorsi functional muscle transfer. The presence of two pulmonary nodules on CT scan staging implied a lung biopsy that showed rectum primary tumour metastases. With these additional findings, the pathology department reassessed the case and reclassified the arm tumour as an MPNST, synchronous with pulmonary adenocarcinoma metastases of the rectum.

Appendiceal neurofibroma with low-grade appendiceal mucinous neoplasm in neurofibromatosis type 1 patient: A case report

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Appendiceal neurofibromas (AN) in Neurofibromatosis type (NF) 1 are rare.

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AN in NF1 with Low-grade appendiceal mucinous neoplasms (LAMNs) are extremely rare.

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AN and LAMNs have potential for malignant transformation.

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Surgical resection is the standard treatment for patients with AN and LAMNs.

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However, appropriate surgical procedure remains controversial.

Introduction

Neurofibromas are a characteristic of the autosomal dominant disorder Neurofibromatosis type 1 (NF1), also known as von Recklinghausen’s disease. Appendiceal neurofibromas are extremely rare, and low-grade appendiceal mucinous neoplasms (LAMNs) have not previously been reported in NF1.

Presentation of case

A 62-year-old man with NF1 was scheduled for elective surgical treatment of an asymptomatic, enlarged and diffusely thickened appendix that remained after curative antimicrobial treatment of acute appendicitis. Laboratory analysis revealed all normal. Colonoscopy showed thickened appendiceal mucosa projecting into the cecum. A sample of the mucosa was found to be pathologically benign. The patient was preoperatively diagnosed with treated acute appendicitis with chronic appendiceal inflammation versus appendiceal neoplasms. Laparoscopic cecectomy was performed. Multiple neurofibromas were observed in the muscle layer, submucosa, and mucosa of the appendix on histopathological examination. Immunohistochemical examination showed positive staining for S-100. Pathologically, the patient was diagnosed with appendiceal neurofibroma consistent with NF1 with LAMNs. His postoperative course was unremarkable. He was discharged on post-operative day 3 and remained in good health 7 month after surgery.

Conclusions

Appendiceal neurofibromas are often preoperatively diagnosed as appendicitis. Appendiceal neurofibromas should be considered in patients with NF1 who are suspected of having appendicitis.

Cell activity during peripheral nerve defect repair process using a nerve scaffold

Peripheral nerve defects, but not artificial nerves, are repaired by endogenous cells. We examined cell activity during the repair process in the presence of autologous nerves and artificial preparations in order to guide future artificial nerve fabrication. PLGA tubes, nerve scaffolds comprising a PLGA tube plus 6,000 fibroin fibers, or autologous nerves were implanted into 10 mm rat sciatic nerve defects (n = 60 per group). Over a period of 1-20 weeks after nerve grafting, sections were stained and imaged to distinguish the cell types present and we quantified the recovery of motor and sensory function in the surgically implanted limb. We observed a decreasing trend in inflammatory cell and fibroblast counts over time which ranked in magnitude as: (PLGA group > nerve scaffold > autologous nerve> sham) and an opposite trend in Schwann cell counts. Differences in withdrawal time from hot water and static sciatic index (SSI) indicated that, after repair, sensory and motor function were best in the sham group, followed by the autologous group, the nerve scaffold group, and the PLGA group. These findings indicate that the inflammatory reaction is significant in the first two weeks after nerve grafting, followed by the rebirth of fibroblasts and Schwann cells, which guide axon regeneration. This inflammatory response was a fundamental stage of peripheral defect repair, but a weaker inflammatory response corresponded to better recovery of sensorimotor functional.