Leiomyosarcomas (LMS) are rare sinonasal malignant tumours with 20 cases of nasal LMS previously reported in the literature. An 81-year-old man presented with an incidental left nasal lesion associated with left nasal obstruction and occasional left-sided blood-stained rhinorrhoea. Nasendoscopic examination showed green coloured polyps filling the left nasal cavity with biopsies showing LMS. CT imaging did not show any bony erosion. No metastases were found on positron emission tomography imaging. The patient underwent endoscopic resection and all surgical margins were clear of disease. The patient was declined postoperative radiotherapy, and serial follow-up has not shown any recurrence to date. Nasal LMS are rare sinonasal smooth muscle tumours and symptoms and radiological findings are often non-specific. Therefore, diagnosis is made on histopathological and immunohistochemical analysis. Due to their invasive nature, the treatment of choice is complete surgical resection, with adjuvant therapy reserved for patients with locally advanced or metastatic disease.

CNS lymphoma involving the trigeminal nerve is a rare condition which presents as a cavernous sinus lesion. It may mimic the radiological appearance of other lesions, and biopsy is essential before considering empirical radiotherapy for lesions in this region. We report the radiological, histopathological and operative findings of a primary non Hodgkin B cell lymphoma involving the trigeminal nerve.