Squamous carcinoma arising in a branchial cleft cyst: have you ever treated one? Will you?

The existence of primary branchiogenic carcinoma – that is, carcinoma arising in a pre-existing branchial cleft cyst (a benign developmental cyst) – has in recent decades been the subject of increasing scepticism. Recognition of the propensity of a variety of head and neck sites – including in particular the tonsil – to give rise to cervical metastases while the primary tumours themselves remain undetected has given rise to the idea that virtually all cystic carcinomas of the neck represent metastatic deposits, whether or not their primary sites are found. A diagnosis of primary branchiogenic carcinoma should be viewed with extreme scepticism, and every effort should be made (e.g. imaging, panendoscopy, elective tonsillectomy) to exclude the existence of a primary site elsewhere, before considering a diagnosis of primary branchiogenic carcinoma.