A schwannoma is a tumour which originates from Schwann cells in the peripheral nervous system. They are usually slow-growing and benign, but can infrequently show malignant transformation.
A 45-year-old patient presented with left foot pain for 10yrs. Investigations of the foot itself had found no cause for the pain. An MRI of the calf (Fig 1) showed a lesion of the tibial nerve. Palpation of the calf at the site of the lesion reproduced the foot pain, and she was scheduled for surgery.
Surgery involved dissection through the calf muscles to identify the tibial nerve and the lesion attached to it (Fig 2).
The lesion was carefully removed taking care not to damage the nerve-fibres draped around the lesion (Fig 3).
The excised lesion (Fig 4) was sent to pathology, and the diagnosis of a schwannoma was confirmed. This is a benign lesion, but left intact it grows slowly, usually causing increasing nerve symptoms/injury with time.
The patient was very pleased with the result of surgery, she woke up with no foot pain. A post-operative MRI showed complete resection of the tumour.
