[Cancerization of first branchial cleft cyst in the parotid gland: one case report].

A rare case of branchiogenic carcinoma from first cleft branchial cyst in the parotid gland is reported. An elderly male patient was admitted to the hospital presented with a mass accompanying with swelling and pain in the right parotid area for 5 days. Total right parotidectomy including the tumor resection and selective neck dissection were performed under general anesthesia. A thick-walled cyst containing necrotic tissue in the parotid gland was found. Postoperative histopathology showed that the tumor contained squamous epithelium and pseudostratified columnar epithelium. The cyst epithelium had atypical hyperplasia with necrosis. Some areas were cancerous with the formation of well-differentiated squamous cell carcinoma and cancer infiltration. No metastasis was found in the cervical lymph nodes. This case was in accordance with the diagnostic criteria of cancerization of the first branchial cleft cyst.