Choanal fungus ball mimicking a tumour

We report the first case of an isolated choanal fungus ball in a 28-year-old man with a previous history of nasopharyngeal carcinoma, who was treated with radiotherapy 14 years ago. The initial diagnosis was a recurrent tumour or a secondary neoplasm. Histopathological examination confirmed a fungal infection. There are no previous reports of a fungus ball located at the posterior choanal region. Although it has been reported that bacteriology of sinonasal region would be different in irradiated patients, there is no study reporting fungal infections in irradiated patients in English literature.In this report, the clinical presentation, relevant radiologic findings and management of sinonasal fungus ball and its relationship with previous radiotherapy were discussed with the literature knowledge.