NF1 and plexiform neurofibroma: Neurofibromas have three main morphologic forms: 1)cutaneous, the most frequent; 2)intraneural, circumscribed to a peripheral nerve; or 3)plexiform, involving multiple fascicles of a major trunk/plexus, pathognomonic of NF1.5, 6In terms of location, multiple bilateral spinal nerve roots tumours are hallmark of NF1, while involvement of spinal roots in sporadic forms is rare.6