A 29-year-old woman consulted because of a 2-year history of a slowly growing mass at the back of her right thigh. This was accompanied by pain radiating to the right leg, especially when she sits on a hard surface or when she accidentally hits the back of her thigh. 

On examination, she had a round, movable mass at the back of her thigh. When the doctor lightly tapped on the mass, the patient would complain of shooting pain and tingling down her leg and foot. MRI showed a nerve sheath tumor. 

The patient underwent surgery to remove the tumor. The tumor arose from the sciatic nerve, one of the largest nerves in the body and is one of the major nerves supplying the lower limbs. After careful dissection, the surgeon was able to separate the tumor from the nerve and excise it completely. 

After the surgery, the patient did not have any shooting pain, weakness, or numbness, and was discharged home the following day. She went back to work after a week. The biopsy result was a schwannoma, a benign (non-cancerous) tumor arising from the covering of the nerve, so no further treatment was needed.