Intracranial metastasis of follicular thyroid carcinoma mimicking cerebellopontine angle tumour

Abstract Cerebellopontine angle (CPA) tumour is most commonly associated acoustic neuroma. The occurrence of metastatic brain tumour at CPA is rare. Follicular thyroid carcinoma is second most common well differentiated thyroid malignancy and brain metastasis is unusual. We would like to report an unusual presentation of follicular thyroid carcinoma with brain metastasis at the CPA region. A 60 year old gentleman presented with occipital headache, slurred speech with positive cerebellar signs and multiple cranial nerve palsies with no neurological deficit to upper and lower limbs. No other significant findings noted on examination. Imaging investigations revealed a CPA tumour. Transnasal transphenoidal tumour debulking was done and biopsy revealed a metastasis of follicular thyroid carcinoma. After total thyroidectomy, the patient was scheduled for radioactive iodine ablation. Metastasis brain tumour with high vascular supply can contribute to difficult tumour debulking. Embolisation and stereotactic therapy are the supporting and alternative method of treatment.