Peripheral Nerve Sheath Tumors.

(PNST)

PNST are malignant tumors of nerve sheath origin and have been referred to as neurofibrosarcoma, malignant schwannoma and haimangiopericytoma. They occur any where in body. PNST are divided mainly in three groups 

1. Peripheral group -  PNST involves nerves away from brain or spinal cord.

2. Root group - Involves nerves immediately adjescent to brain or spinal cord

3. Plexus group - involves brachial or lumbosacral plexsus

       True peripheral forms of PNST are easily treatable.

PNST are poorly defined tumors and appear like fibrosarcomas. They are adherent to deeper tissues and infiltrate underlying fascia,muscle and skin.

        All PNST's are malignant but have moderate metastetic rate. Recurrence after conservative surgery is very common. modified staging and grading system for these PNST is available.

         The best chemotherapeutic agent is doxorubicin and palliative radiation at the rate of 30 Gy usually undertaken.Survival is 12 to 24 months maximum, reported after diagnosis.