Clinicopathological characteristics of collision tumours of thyroid in the clinical setting of medullary thyroid carcinoma

Thyroid collision tumours are relatively rare entities and are usually undiagnosed pre-operatively. The prognosis of the disease primarily depends on tumour aggressiveness the of medullary thyroid carcinoma component. A combined follow up with tumour markers and imaging, including positron emission tomography/computed tomography molecular imaging approaches should be adopted.