808 A Fascinating Case of Anosmia in an Adult: Benign Peripheral Nerve Sheath Tumour Managed at a Tertiary NHS Centre

Abstract

Abstract Introduction A nerve sheath tumour is slow growing lesion in the myelinated connective tissue surrounding the nerve fibres. Paranasal schawannomas are rare and often clinically misdiagnosed. Case Report An 80-year-old male referred to us with suspected olfactory neuroblastoma. He initially presented to his local unit with anosmia, nasal blockage, and epistaxis. There was history of right temple skin cancer 20 years ago and he is being currently being treated for hypertension. The biopsy results from local hospital were S100 and CD56 positive and preliminarily suggestive of olfactory neuroblastoma or ancient schwannoma. On review in clinic, he had a large left sided anterior sinonasal lesion obstructing the cavity. The patient was planned for elective endoscopic or open resection and underwent further imaging to aid surgical planning. The CT Head was suggestive of a large left anterior sinonasal tumour, abutting the cribriform plate which is thinned and possibly focally dehiscent. Abutment of the left lamina papyracea which is bowed and thinned. The patient underwent Endoscopic resection of left sinonasal tumour and skull base repair with fat, fascia lata and septal flip flop flap. The patient recovered well postoperatively and was discharged home 5 days after his procedure. The histology confirmed benign peripheral nerve sheath tumour. Conclusion Peripheral nerve sheath tumours can present with various unusual symptoms and may prove difficult to diagnose. Hence a multidisciplinary approach is beneficial to guide management in such complex cases.