Malignant degeneration of a branchial cyst: A case report

Malignant degeneration of a branchial cyst is rare (Thompson, 1997). It varies from 4% to 22% (Unal et al., 2005). A74-year-old man presented to our department with a left painless upper neck mass which was excised and histopathology revealed squamous cell carcinoma in a cystic lesion. The appropriate clinical tests and imaging were performed to determine the possible presence of a primary tumor. No primary carcinoma was found. This finding suggests that this was a malignant degeneration of a branchial cyst. The patient was treated with adjuvant radiotherapy and followed up over a 2-year-period and no recurrence was found. The development of an epidermoid carcinoma in situ in the amygdaloid cyst wall is a very rare entity. The challenge is to be able to distinguish between cystic metastasis of squamous cell carcinoma of the aerodigestive tract and a primary epidermoid carcinoma developed in the wall of an amygdaloid cyst. Martin and Khafif proposed some criteria to confirm the diagnosis of branchiogenic carcinoma.