Primary Intraosseous Malignant Peripheral Nerve Sheath Tumor of Metacarpal Bones of the Hand in a Patient Without Neurofibromatosis 1: Report of a Rare Case

Abstract

Malignant peripheral nerve sheath tumor (MPNST) usually arises in peripheral nerve sheath cells. The intraosseous location of MPNST is rare. Mandible is the most common site of bony involvement. Involvement of bones of the hand is quite unusual. We report a case of MPNST involving metacarpal bones of the left hand treated with surgery followed by adjuvant radiation and chemotherapy and review the pertinent literature.

Keywords: Bone; malignant peripheral nerve sheath tumor; metacarpal; radiotherapy.

Figure 1

Contrast-enhanced magnetic resonance imaging of the left hand showing a diffusely enhancing 6.7 cm × 3.4 cm × 3.0 cm expansile destructive lesion involving the entire third metacarpal bone sparing the proximal and distal articular surfaces

Figure 2

Repeat magnetic resonance imaging of the left hand after induction chemotherapy showing a 7.3 cm × 3.8 cm × 3.7 cm tumor involving the third metacarpal bone with extension into proximal and distal epiphysis, third metacarpophalangeal joint, base of the second metacarpal bone, and the interosseous muscles

Figure 3

Malignant epithelioid tumor cells in vague lobular arrangement (a, H and E, ×100). Tumor cells have large pleomorphic, hyperchromatic nuclei, clumped chromatin, irregular thick nuclear membrane, and moderate amount of eosinophilic cytoplasm (b, H and E, ×400). Tumor cells are strongly immunoreactive to neuron-specific enolase (c, ×200) and CD56 (d, ×200)

Figure 4

Photograph of the radiation portal encompassing the postoperative scar (a) and the tumor bed (b) with a margin of 2 cm; the patient was simulated in swimmer's hand position using a customized styrofoam cutout for immobilization