Arm malignant peripheral nerve sheath tumour: a rare clinical presentation

Area of Science:

• Oncology
• Pathology
• Surgical Oncology

Background:

• Soft tissue sarcomas are rare, comprising ~1% of malignancies.
• Malignant peripheral nerve sheath tumours (MPNST) represent an extremely rare subtype.
• Accurate diagnosis and classification are crucial for effective treatment strategies.

Observation:

• An 81-year-old male presented with a growing, painless right arm mass.
• Initial MRI revealed a well-defined, encapsulated mass within the biceps muscle.
• Biopsy indicated a spindle cell tumour with significant cytonuclear pleomorphism.

Findings:

• The arm tumour was ultimately reclassified as an MPNST.
• Synchronous pulmonary nodules were confirmed as metastases from a primary rectal adenocarcinoma.
• The patient underwent successful wide excision and latissimus dorsi muscle flap reconstruction.

Implications:

• This case underscores the importance of comprehensive staging and reassessment in complex oncological cases.
• It highlights the diagnostic challenges posed by rare tumours and metastatic disease.
• Multidisciplinary collaboration is essential for accurate diagnosis and optimal patient management.