Combined manifestation of a neurofibroma and a nerve sheath ganglion in the ulnar nerve after radiotherapy in early childhood

Occurrence of clinically symptomatic benign neurofibromas of peripheral nerves after radiotherapy is a rarity. We saw a 55-year-old female who developed progressive failure of the ulnar nerve 55 years after 20 Gy ²²⁶Ra brachytherapy of a haemangioma of the left elbow at the age of 3 months. Nerve compression at the sulcus segment was caused by the intraneural growth of a neurofibroma and the formation of a nerve sheath ganglion. The rapidly progressive symptoms required operative treatment. Due to the infiltrating tumour growth we decided to resect this segment of the ulnar nerve and reconstruct it with an interfascicular nerve graft. This case demonstrates a rare possible consequence of radiotherapy in which the co-existence of two benign lesions required surgical intervention. Radiotherapy-induced malignant tumours and tissue scarring are well known as complications. The present case suggests further possible late effects of radiotherapy to consider.