Carcinoma occurring in branchial cleft cysts.

In order to find histological data in the differentiation between branchial cleft carcinomas and metastatic carcinomas, the specimens from 154 patients with branchial cleft cysts and 7 patients with an isolated tumour in the neck with unknown primary tumour were reviewed and compared with 10 normal lymph nodes. Absence of lymph node structures as peripheral lobulation, internodular trabeculae and perinodular sinuses in branchial cleft cystc, are found valuable for distinguishing primary carcinoma of branchial cleft cysts from metastases. A correct diagnosis of this rare tumour is important in order to avoid overtreatment of these patients, who have a good prognosis if treated with surgical excision only.