What is a Malignant Peripheral Nerve Sheath Tumour

Description: A malignant peripheral nerve sheath tumour (MPNST) is a type of cancer called a soft tissue sarcoma. Soft tissue sarcomas are cancers that develop in the supporting or connective tissues of the body (such as muscle, fat, nerves and blood vessels). MPNSTs probably start from Schwann cells, which form the protective sheath around nerves. People in their 20s to 50s are most likely to be affected. Occasionally children can develop MPNSTs but this is rare. It is not known what causes these tumours. People who have an inherited condition called neurofibromatosis type 1 (NF1) have an increased risk of developing MPNST. About half of MPNSTs are found in people with NF1.