Neurinoma tumour. Light micrograph of a section through a neurinoma from a peripheral nerve. A neurinoma, or Schwannoma, is a tumour arising from Schwann cells, cells that wrap around and protect nerve fibres. The tumour is benign (non-cancerous) and does not spread, but its growth may damage the affected nerve by compressing it. Symptoms due to this can range from tingling to paralysis of the area supplied by the nerve. Neurinomas may be removed surgically, but if they have grown large removal often leads to a loss of the nerve's function.