RARE DISEASE
Malignant peripheral nerve sheath tumor
Malignant peripheral nerve sheath tumor
Malignant peripheral nerve sheath tumor
Synonyms: MPNST, Malignant neurilemmoma, Malignant neurofibroma, Malignant schwannoma, Neurofibrosarcoma, Neurogenic sarcoma
Synonyms: MPNST, Malignant neurilemmoma, Malignant neurofibroma, Malignant schwannoma, Neurofibrosarcoma, Neurogenic sarcoma
Synonyms: MPNST, Malignant neurilemmoma, Malignant neurofibroma, Malignant schwannoma, Neurofibrosarcoma, Neurogenic sarcoma
Drug discovery
1
drug
With orphan designation
Overview
Malignant peripheral nerve sheath tumor (MPNST) is a rare, aggressive soft tissue sarcoma arising from peripheral nerve sheaths, often linked to neurofibromatosis type 1 (NF1) or prior radiation [1][8][14]. Characterized by rapid growth, high recurrence rates (~40%), and frequent metastasis (commonly to lungs), it has a poor prognosis (5-year survival: 30-50%) [3][12][16]. Diagnosis relies on imaging (MRI/CT) and biopsy, while treatment emphasizes surgical resection with adjuvant radiotherapy; chemotherapy offers limited benefit in advanced disease [7][19][20].
Population
Annual incidence of 1.0-1.26 per million; 50% associated with NF1 (lifetime risk: 8-13%) [1][14][16].
Highest incidence in Black individuals vs. White/Asian groups; median diagnosis age 30-50 [2][6][12].
Gender distribution varies (slight male predominance in some studies, female in others) [2][14][18].
Therapies
Categories: rare neoplastic diseases, rare neurological diseases
Research Papers
1,008 drug discovery papers about Malignant peripheral nerve sheath tumor, with 4 first-in-class and 16 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
1,008 drug discovery papers about Malignant peripheral nerve sheath tumor, with 4 first-in-class and 16 next-in-class emerging drug candidates forecasted to outperform the average preclinical success rate. Recent publications:
2026-08-14 | TEAD inhibitors re-sensitize drug-resistant NF1 MPNST cells to MEK inhibitors.
Neurofibromatosis type 1 (NF1) patients develop non-malignant neurofibromas that can progress to Malignant Peripheral Nerve Sheath Tumors (MPNSTs). NF1 neurofibromas are treated with MEK inhibitors, such as mirdametinib and selumetinib, because they are driven by activation of the Ras/Raf/MEK/ERK signaling pathway. We developed two MEK-resistant MPNST cell lines by passaging cells in selumetinib for approximately three months. The cells were resistant to 15 other MEK inhibitors in a high-throughput screen but were re-sensitized by co-treatment with a TEAD inhibitor. These results suggest that TEAD inhibitors synergize with MEK inhibitors to overcome resistance and enhance therapeutic efficacy in MPNSTs.
2026-08-11 | Combined FAK and MEK inhibition suppresses chromosome 8 gain malignant peripheral nerve sheath tumors.
Aneuploidy is a hallmark of cancer often associated with inferior prognosis. Copy number gains of chromosome 8 (chr8) are recurrent in multiple cancers, including breast, prostate, colorectal cancers, and sarcomas such as malignant peripheral nerve sheath tumors (MPNSTs). MPNSTs are aggressive, hard-to-treat sarcomas frequently linked to the Neurofibromatosis type 1 (NF1) cancer predisposition syndrome. To investigate the role of chr8 gain in MPNST pathogenesis, we performed a CRISPR knockout screen and identified 58 essential genes on chr8, including PTK2, which encodes focal adhesion kinase (FAK). We evaluated FAK as a therapeutic target and tested small-molecule FAK inhibitors (FAKi) alone or combined with RAF/MEK inhibitors (RAF/MEKi), a class of agents relevant to NF1-deficient tumors with ERK pathway hyperactivation. Both pharmacological and genetic inhibition of FAK reduced MPNST cell proliferation in vitro and tumor growth in vivo. Combined FAKi and RAF/MEKi treatment further suppressed phosphorylation of FAK, STAT3, and AKT while increasing cleaved caspase-3 and PARP-1, indicating enhanced apoptosis. In MPNST patient-derived xenograft (PDX) models, combination therapy significantly reduced tumor growth, showing superior efficacy, particularly in chr8 gain MPNST-PDX. These results support FAK/RAF/MEK co-targeting as a promising therapeutic strategy for chr8 gain MPNST and related tumors.
2026-08-07 | Giant cervicothoracic malignant peripheral nerve sheath tumor in neurofibromatosis type I: a case report of integrated management with multimodal guidance.
Neurofibromatosis type 1 (NF1) is a genetic disorder predisposing patients to malignant peripheral nerve sheath tumors (MPNSTs), which represent a leading cause of mortality with poor therapeutic outcomes. Large MPNSTs with NF1 are extremely rare, and only a few clinical reports are published on this disease. We describe a case of giant cervicothoracic MPNST with major vessels encased and present the clinical profiles, radiological findings, operative management, and follow-up data, along with a literature review. A 30-year-old male patient complained of an incidentally discovered painful mass in the right neck that had been progressively enlarging, accompanied by right hand weakness and intrinsic muscle atrophy. Contrast-enhanced MRI revealed a giant tumor closely related with the right brachial plexus and intervertebral foramina of C6-T2. The right subclavian artery and internal jugular vein were tightly encased by the tumor. A multidisciplinary approach incorporating advanced 3D imaging, preoperative vertebral artery embolization, and en bloc resection with vascular reconstruction achieved successful tumor removal while preserving neurological function. The patient received adjuvant radiotherapy and was followed up on the 6th and 12th months postoperatively. There were no complaints or signs of recurrence. The successful long-term outcome provides a valuable template for managing similar high-risk cases, though long-term surveillance remains crucial due to the high recurrence potential of MPNSTs. This report contributes to the limited literature on radical surgical management of NF1-associated MPNSTs and emphasizes the critical balance between oncological control and functional preservation in these challenging cases.
2026-08-05 | DNA Hypomethylation Is Not Cell Intrinsically Toxic to Polycomb Repressive Complex 2 Deficient Malignant Peripheral Nerve Sheath Tumors.
Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas and the most common cause of disease-associated death for neurofibromatosis type 1 (NF1) patients. In the context of NF1, MPNSTs develop from benign premalignant precursors and the transition to malignancy is typically accompanied by loss of the polycomb repressive complex 2 (PRC2), which results in aberrant upregulation of over 1200 genes due to global depletion of histone H3 lysine 27 trimethylation (H3K27me3). Previous studies suggest cells compensate for the loss of this repressive histone mark via hypermethylation of the genome. Here we analyzed genome-wide DNA methylation and the transcriptome in MPNST cell lines and isogenic PRC2-deficient and -proficient CRISPR-engineered immortalized human Schwann cells. In addition to effects of PRC2 status, we also measured the effects of two DNA methyltransferase inhibitors (DNMTi), decitabine and azacitidine. We found that PRC2 status does not affect global DNA methylation or average methylation levels across specific genomic features. Furthermore, decitabine and azacitidine have differential effects on MPNSTs. While both DNMTis hypomethylate the genome, they upregulate different targets. Azacitidine upregulates genes involved in RNA processing pathways and exhibits direct tumor cell cytotoxicity, while decitabine upregulates genes involved in the immune response, has no direct-cell killing effects, and likely suppresses tumor growth in vivo by altering the tumor microenvironment. We show that DNA hypomethylation alone is insufficient to kill MPNST cells, regardless of PRC2 status. Consequently, these findings suggest that DNMT inhibitors should be utilized in combination with other targeted therapies for MPNST patients.
2026-08-02 | Malignant peripheral nerve sheath tumor development during MEK inhibitor treatment: A pre-clinical study and a clinical case series.
People with Neurofibromatosis type 1 (NF1) are at risk of developing benign and malignant peripheral nerve sheath tumors (MPNST). In NF1, the overall lifetime risk of MPNST is estimated at 8%-13%, with increased risk associated with specific germline mutations and larger benign tumor burden. Selumetinib, a mitogen-activating protein kinase kinase inhibitor (MEKi), was the first FDA-approved therapy for children with inoperable, symptomatic benign nerve sheath tumors known as plexiform neurofibromas (PN). While clinical and preclinical studies indicate that MEKi monotherapy is unlikely an effective treatment for MPNST, the potential impact of long-term MEKi therapy on the risk of malignant transformation of benign PN is not yet known. We evaluated the impact of selumetinib on the development of MPNST in a pre-clinical orthotopic mouse model of Nf1-Arf mutant Schwann cells. In addition, we analyzed MPNST development on our phase 1/2 clinical trial of selumetinib for PN (NCT01362803). In the preclinical mouse model, selumetinib did not accelerate the development or growth of MPNST. On the selumetinib clinical trial, 4 of 99 participants developed an MPNST either during or shortly after treatment. All were at increased risk for developing MPNST based on a large PN tumor burden, NF1 microdeletion, or presence of a pre-malignant atypical neurofibroma prior to starting selumetinib treatment. While these findings do not indicate acceleration of MPNST development on selumetinib, patients receiving MEKi for PN, in particular those with high-risk features, remain at risk for malignant transformation and should be monitored accordingly.
2026-08-14 | TEAD inhibitors re-sensitize drug-resistant NF1 MPNST cells to MEK inhibitors.
Neurofibromatosis type 1 (NF1) patients develop non-malignant neurofibromas that can progress to Malignant Peripheral Nerve Sheath Tumors (MPNSTs). NF1 neurofibromas are treated with MEK inhibitors, such as mirdametinib and selumetinib, because they are driven by activation of the Ras/Raf/MEK/ERK signaling pathway. We developed two MEK-resistant MPNST cell lines by passaging cells in selumetinib for approximately three months. The cells were resistant to 15 other MEK inhibitors in a high-throughput screen but were re-sensitized by co-treatment with a TEAD inhibitor. These results suggest that TEAD inhibitors synergize with MEK inhibitors to overcome resistance and enhance therapeutic efficacy in MPNSTs.
2026-08-11 | Combined FAK and MEK inhibition suppresses chromosome 8 gain malignant peripheral nerve sheath tumors.
Aneuploidy is a hallmark of cancer often associated with inferior prognosis. Copy number gains of chromosome 8 (chr8) are recurrent in multiple cancers, including breast, prostate, colorectal cancers, and sarcomas such as malignant peripheral nerve sheath tumors (MPNSTs). MPNSTs are aggressive, hard-to-treat sarcomas frequently linked to the Neurofibromatosis type 1 (NF1) cancer predisposition syndrome. To investigate the role of chr8 gain in MPNST pathogenesis, we performed a CRISPR knockout screen and identified 58 essential genes on chr8, including PTK2, which encodes focal adhesion kinase (FAK). We evaluated FAK as a therapeutic target and tested small-molecule FAK inhibitors (FAKi) alone or combined with RAF/MEK inhibitors (RAF/MEKi), a class of agents relevant to NF1-deficient tumors with ERK pathway hyperactivation. Both pharmacological and genetic inhibition of FAK reduced MPNST cell proliferation in vitro and tumor growth in vivo. Combined FAKi and RAF/MEKi treatment further suppressed phosphorylation of FAK, STAT3, and AKT while increasing cleaved caspase-3 and PARP-1, indicating enhanced apoptosis. In MPNST patient-derived xenograft (PDX) models, combination therapy significantly reduced tumor growth, showing superior efficacy, particularly in chr8 gain MPNST-PDX. These results support FAK/RAF/MEK co-targeting as a promising therapeutic strategy for chr8 gain MPNST and related tumors.
2026-08-07 | Giant cervicothoracic malignant peripheral nerve sheath tumor in neurofibromatosis type I: a case report of integrated management with multimodal guidance.
Neurofibromatosis type 1 (NF1) is a genetic disorder predisposing patients to malignant peripheral nerve sheath tumors (MPNSTs), which represent a leading cause of mortality with poor therapeutic outcomes. Large MPNSTs with NF1 are extremely rare, and only a few clinical reports are published on this disease. We describe a case of giant cervicothoracic MPNST with major vessels encased and present the clinical profiles, radiological findings, operative management, and follow-up data, along with a literature review. A 30-year-old male patient complained of an incidentally discovered painful mass in the right neck that had been progressively enlarging, accompanied by right hand weakness and intrinsic muscle atrophy. Contrast-enhanced MRI revealed a giant tumor closely related with the right brachial plexus and intervertebral foramina of C6-T2. The right subclavian artery and internal jugular vein were tightly encased by the tumor. A multidisciplinary approach incorporating advanced 3D imaging, preoperative vertebral artery embolization, and en bloc resection with vascular reconstruction achieved successful tumor removal while preserving neurological function. The patient received adjuvant radiotherapy and was followed up on the 6th and 12th months postoperatively. There were no complaints or signs of recurrence. The successful long-term outcome provides a valuable template for managing similar high-risk cases, though long-term surveillance remains crucial due to the high recurrence potential of MPNSTs. This report contributes to the limited literature on radical surgical management of NF1-associated MPNSTs and emphasizes the critical balance between oncological control and functional preservation in these challenging cases.
2026-08-05 | DNA Hypomethylation Is Not Cell Intrinsically Toxic to Polycomb Repressive Complex 2 Deficient Malignant Peripheral Nerve Sheath Tumors.
Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas and the most common cause of disease-associated death for neurofibromatosis type 1 (NF1) patients. In the context of NF1, MPNSTs develop from benign premalignant precursors and the transition to malignancy is typically accompanied by loss of the polycomb repressive complex 2 (PRC2), which results in aberrant upregulation of over 1200 genes due to global depletion of histone H3 lysine 27 trimethylation (H3K27me3). Previous studies suggest cells compensate for the loss of this repressive histone mark via hypermethylation of the genome. Here we analyzed genome-wide DNA methylation and the transcriptome in MPNST cell lines and isogenic PRC2-deficient and -proficient CRISPR-engineered immortalized human Schwann cells. In addition to effects of PRC2 status, we also measured the effects of two DNA methyltransferase inhibitors (DNMTi), decitabine and azacitidine. We found that PRC2 status does not affect global DNA methylation or average methylation levels across specific genomic features. Furthermore, decitabine and azacitidine have differential effects on MPNSTs. While both DNMTis hypomethylate the genome, they upregulate different targets. Azacitidine upregulates genes involved in RNA processing pathways and exhibits direct tumor cell cytotoxicity, while decitabine upregulates genes involved in the immune response, has no direct-cell killing effects, and likely suppresses tumor growth in vivo by altering the tumor microenvironment. We show that DNA hypomethylation alone is insufficient to kill MPNST cells, regardless of PRC2 status. Consequently, these findings suggest that DNMT inhibitors should be utilized in combination with other targeted therapies for MPNST patients.
2026-08-02 | Malignant peripheral nerve sheath tumor development during MEK inhibitor treatment: A pre-clinical study and a clinical case series.
People with Neurofibromatosis type 1 (NF1) are at risk of developing benign and malignant peripheral nerve sheath tumors (MPNST). In NF1, the overall lifetime risk of MPNST is estimated at 8%-13%, with increased risk associated with specific germline mutations and larger benign tumor burden. Selumetinib, a mitogen-activating protein kinase kinase inhibitor (MEKi), was the first FDA-approved therapy for children with inoperable, symptomatic benign nerve sheath tumors known as plexiform neurofibromas (PN). While clinical and preclinical studies indicate that MEKi monotherapy is unlikely an effective treatment for MPNST, the potential impact of long-term MEKi therapy on the risk of malignant transformation of benign PN is not yet known. We evaluated the impact of selumetinib on the development of MPNST in a pre-clinical orthotopic mouse model of Nf1-Arf mutant Schwann cells. In addition, we analyzed MPNST development on our phase 1/2 clinical trial of selumetinib for PN (NCT01362803). In the preclinical mouse model, selumetinib did not accelerate the development or growth of MPNST. On the selumetinib clinical trial, 4 of 99 participants developed an MPNST either during or shortly after treatment. All were at increased risk for developing MPNST based on a large PN tumor burden, NF1 microdeletion, or presence of a pre-malignant atypical neurofibroma prior to starting selumetinib treatment. While these findings do not indicate acceleration of MPNST development on selumetinib, patients receiving MEKi for PN, in particular those with high-risk features, remain at risk for malignant transformation and should be monitored accordingly.
Access all drug discovery papers and probability of success in trials forecasts:
Access all drug discovery papers and probability of success in trials forecasts:
Drug Discovery Landscape
1 orphan drug designation for Malignant peripheral nerve sheath tumor.
1 orphan drug designation for Malignant peripheral nerve sheath tumor.
Drug | Therapy type | Regulator | Orphan designation | Approval | Sponsor |
|---|---|---|---|---|---|
Small molecule inhibitor of PRMT5 (protein arginine methyl transferase 5) | small molecules | FDA | 2022-07-25 | — | Tango Therapeutics |
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