Intrathyroidal Lymphoepithelial (Branchial) Cyst: Diagnostic and Management Challenge of a Rare Entity

Intrathyroidal lymphoepithelial (branchial) cysts are very rare, and only few cases have been previously reported worldwide. Here, we report on a case of a male patient with such a rare histological finding after a routine left hemithyroidectomy performed for a nearly 4 cm cystic left thyroid lobe lesion. The patient was an 80-year-old man, fact that makes, to our knowledge, our patient the oldest in the current literature. Through a review of the existing literature, we concluded that although some entities are extremely rare, they should also be taken under consideration in everyday clinical differential diagnosis of otherwise common medical cases, such as our presented case. Such cases pose a differential dilemma for the clinical doctor in order to make a correct diagnosis, if that is possible, and then proceed with the efficient treatment.