Synonyms

• MPNST
• Malignant schwannoma

Category

Soft tissue

Behaviour

Malignant

Grade

High

Gender

Both equally

Tissue of Origin

Neural

Epidemiology

• Malignant nerve sheath tumour
• Peak incidence 2nd-5th decades
• 25-30% associated with NF1
• Often arises from Benign nerve sheath tumour
• Large and deep lesions at Higher risk

Clinical Features

• Rapid growth
• Pain
• Neurological symptoms (compression)
• Constitutional symptoms if metastatic

Location

• Extremities (most common)
• Trunk
• Head and neck
• Retroperitoneum

Imaging

• MRI: heterogeneous High-grade appearance
• Involvement of nerve sheath and soft tissues
• Hemorrhage and necrosis common

Pathology

• High-grade spindle cell sarcoma
• Myxoid or fascicular pattern
• High mitotic rate
• Necrosis typical
• TP53 mutations, other alterations

Genetics

• NF1 loss or inactivation (25-30%)
• TP53, CDKN2A alterations common

Treatment

• Wide surgical resection: primary
• Chemotherapy (MAID or similar): adjuvant
• Radiotherapy: adjuvant if margins or deep

Prognosis

• 50% 5-year survival
• NF1-associated: worse prognosis
• High metastatic potential
• Pulmonary metastases common

Key Points

• High-grade malignancy
• Screen for NF1
• Multimodal therapy standard
• NF1 association worsens prognosis

Workup - Blood Tests

FBC, U&E, LFTs, LDH

Workup - Local Imaging

• MRI primary site: local staging
• CT chest: pulmonary staging
• Whole-body imaging: consider PET-CT

Workup - Biopsy

Core needle or open: confirm High-grade sarcoma

Workup - Staging

• CT chest: pulmonary metastases
• Consider head/abdomen if High-risk

Workup - Other

• MDT at soft tissue sarcoma centre
• NF1 testing if not previously diagnosed
• Genetic counselling

Follow-up Summary

• Year 1: Post-operative visit within first 6 weeks; 3–4 monthly clinical examination and CXR; image prosthesis at 6 months and 1 year
• Year 2: 3–4 monthly clinical examination and CXR; image prosthesis annually
• Years 3–4: 6-monthly clinical examination and CXR; image prosthesis annually
• Years 5–10: Annual clinical examination and CXR; image prosthesis annually
• Discharge at 10 years after surgery