A rare metastatic follicular thyroid carcinoma masquerading as primary sinonasal carcinoma presentation with unusual orbit, skull base and brain metastases

Tumour involving the sinonasal tract account for only 1% of all malignancies. The large majority tumours affecting are mainly primary neoplasm or from direct extension adjacent region; metastatic tumour extremely rare. Most metastases originate carcinoma inferior to clavicle, including renal, breast, lung, and prostate. incidence sphenoid sinus even We describe a rare case FTC tract, mimicking presentation, with unusual orbit, skull base brain metastases.A 66-year-old lady history subtotal thyroidectomy presented epistaxis associated proptosis left eye. Nasal endoscopy revealed vascularised mass occupying entire nasal cavity. Endoscopic transnasal biopsy was performed which showed positive immunochemical staining thyroglobulin, thyroid transcription factor-1. Computed tomography angiography demostrated vascular maxillary sinus, bilateral ethmoid sinuses. causing erosion septum pterygoid plates temporal bone, infratemporal fossa intracranial. Patient received stimulating hormone suppression therapy followed by radio-iodine ablation.As surprisingly rare, purpose our study is raise awareness regarding possibility metastatizing completion intervention crucial better future prognosis. Thyroid should be considered in differential diagnosis potential patient orbital metastases.