Metastatic malignant peripheral nerve sheath tumor. A diagnostic surprise

Malignant peripheral nerve sheath tumours (MPNSTs) are rare soft tissue tumors that arise from pre-existing plexiform neurofibromas or within a normal peripheral nerve. They are aggressive tumors with high rates of recurrence and distant metastases, the most common sites of metastasis being the lung followed by bone.
A 46 year old gentleman presented with breathlessness and chest pain three years after post amputation of left thumb for an ulcerative growth. CECT thorax showed a left upper lobe mass with pleural and pericardial effusion. Within a month of presentation he worsened and succumbed to the disease. Antemortem biopsy of the left hand ulcerative growth showed features suggestive of malignant peripheral nerve sheath tumour- epithelioid variant and post mortem liver and lung biopsy showed metastasis of MPNST. The diagnosis was a malignant peripheral nerve sheath tumor with lung, liver and cardiac metastasis.
This case report aims to highlight the importance of upfront aggressive multimodality local therapy for achieving local disease control in patients presenting with localised MPNST and regular follow up for early detection of relapse and metastasis.