The patient has very rare transformation of the tumor behavior. The first three operation confirmed presence of benign schwannoma by different histopathologists and now showing a malignant tumor.

This is the 125th case using the MultiGen. The purpose is to identify the neural structures and avoiding their damage. It became a usual part of the spine and peripheral nerves surgery. Click here for reference.

The recurrence was due to huge dimensions of the tumor and involvement of most of the sciatic nerve and its divisions. If you notice there is a small schwannoma at the contra-lateral side. 

The patient was operated by me 29-July-1997 for schwannoma posterior aspect of the left knee. The patient then was operated for recurrence by me 30-June-2002, then for second recurrence 03-March-2011. The patient then came 01-July-2017 telling that the mass started to appear 1 year ago and continued to enlarge.

On examination, the patient is neurologically free, except for the mass in the lower third of the leg above the knee. The incision showing abnormal veins at the medial lower part of the old scar.

The patient was sent for investigations and an extended MRI of the area with contrast and TWIST were performed. The mass is huge and multilobulated pushing the tibial nerve anterior and engulfing the peroneal nerve. There are feeders to the mass in its lower compartments which is involving the skin directly.

The old incision was refreshed and the sciatic nerve was identified above the lesion and the tibial and peroneal nerve were also identified at the lower area of the dissection. The tumor was reaching the skin. The tumor was multi compartmental and it was necessary to remove it several parts. Both tibial and peroneal nerves were inside the tumor and sharp dissection was carried on. The tibial nerve was lateral and the peroneal to the medial side. Dissection of the tibial nerve was relatively easy, but the peroneal nerve was severely adherent to the tumor, that dissection caused slight injury to one fascicle of the nerve, which later was repaired by 6 zero nylon. The pushed upward nerves to the biceps and surrounding muscles were also preserved. The tibial nerve before dissection was responding will to 0.6 V and the peroneal nerve to 0.9 V. After total resection the tibial nerve showed response to 0.6 V and the peroneal nerve to 0.7V. The patient was sent to control MRI of the area with contrast and only hematoma was seen in the bed with the running 2 nerves. Routine closure of the wound with removal of the previous sinus, which was noticed after the previous surgery. Redivac drain with negative pressure. The tumor was sent for histological verification to rule out signs of malignancy.

Smooth postoperative recovery. The power of the dorsi and planterflexion of the left foot was 5/5. He was sent to the ward.

The final histological result was myxoid liposarcoma transforming to round cell liposarcoma with areas of ischemic infarctions. (Dr. Salah Al-Jitawi FRCPath, FIAC). After telephone communications the final histologic result was neural sheath sarcoma.

The patient then came 20-July-2017 with healed wound, but about 70 ml of blood evacuated from under the skin. There is hypalgesia left L5 territory with no motor deficit.

The patient then came 16-September-2017 with clean wound and no collection. Advised to perform MRI to the involved area with contrast, which was done 17-September-2017 showing collection of fluid.

The patient then came 11-December-2018 with MRI done to the area showing three rounded masses with reactive changes of the skin. He was seen at Cancer Center and they suggested to him, total amputation of the left leg, but I advised him to undergo radiation and to be reevaluated after one year. He is neurologically free.