Granular Cell Tumor: An Unusual Cause of Common Peroneal Neuropathy

Granular cell tumors, also known as Abrikossoff’s tumors, are rare soft-tissue tumors, and their occurrence in the peripheral nerves has been very rarely reported. We present the case of a 35-year-old woman with common peroneal neuropathy due to a granular cell tumor, who complained of foot dragging. Common peroneal neuropathy was confirmed by electrophysiology. The tumor mass was observed using ultrasonography and magnetic resonance imaging. The tumor was surgically excised, the tumor cells stained positive for S-100, and eosinophilic granular cytoplasm was observed using microscopy. To the best of our knowledge, this is the first report of a granular cell tumor involving the common peroneal nerve.