PP15.7 – 2958: A rare case of solitary mastoid antrum neurofibroma in a child presenting with chronic otorrhoea

Abstract

Objective Neurofibroma is a benign peripheral nerve sheath tumour, which has a frequent association with Neurofibromatosis 1. Solitary neurofibromas are uncommon in young children. A few cases of solitary neurofibromas of maxillary antrum have been reported in the adult population; however, there have been no reports of solitary mastoid antrum neurofibroma even in adulthood. Methods We report a case of solitary mastoid antrum neurofibroma in a young child who presented with recurrent chronic otorrhoea. Results A 5-year-old boy was referred to our neurofibromatosis clinic. He has had problems with ear infections since the age of 7 months. He had chronic bilateral mucopurulent otorrhoea and was managed with recurrent topical and oral antibiotics. He has had early extrusions of grommets twice. He developed central perforation of left tympanic membrane. At 4.5 years of age he underwent a left cortical mastoidectomy. The histopathology examination of this tissue, including S100 staining positivity confirmed the diagnosis of a neurofibroma. He underwent a thorough clinical evaluation to look for features of Neurofibromatosis 1. There were no cafe au lait patches or a family history of Neurofibromatosis 1. His development and learning were age appropriate. His eye examination and MRI brain scan were normal. His symptoms of otorrhoea on the left side have now resolved and there has been no subsequent recurrence. Conclusion Neurofibroma is a common benign peripheral nerve sheath tumour, which is largely associated with Neurofibromatosis 1. To our knowledge, this is the first case of a solitary mastoid antrum neurofibroma reported in literature. This case is unique, not only because of the fact that mastoid antrum is a rare site for neurofibroma, but also because of the very young age at presentation with a common childhood symptom of otorrhoea.