Plexiform Neurofibroma of the Eye Region Occurring in Patients Without Neurofibromatosis Type 1

PURPOSE: The purpose of the present study was to investigate the correlation between Plexiform Neurofibroma (PN) of the eye region and Neurofibromatosis type 1 (NF1). According to the textbooks of ophthalmology, PN and NF1 are very closely linked. Our clinical experience raised doubts about this, however. METHODS: All biopsy reports from the Eye Pathology Institute, Copenhagen, for the 10-year period from 1999 to 2008 with PN as the histological diagnosis were identified. From the pathology referral forms, we determined whether the patients had had a history of NF1, and the medical records were reviewed for symptoms and signs of NF1. Patients with no known NF1 were invited for a clinical examination and a blood test for mutation analysis. RESULTS: 13 patients had been given the histological diagnosis of PN of the eye region during the 10-year period. Of these, 10 patients fulfilled the National Institute of Health (NIH) diagnostic criteria for NF1, but 3 patients had PN of the eye region as the only sign, and thus did not have NF1. In 2 of these patients, mutation analysis was performed on blood, and was negative. CONCLUSION: PN of the eye region is suggestive of NF1 but not pathognomonic of this disease.