悪性頚動脈小体腫ようの一例 本邦悪性例の検討

Abstract

Carotid body tumor is a rare neoplasm; only about 500 cases have been reported in the world literature. This paper describes a recent case of malignant carotid body tumor and reviews 17 cases reported in the Japanese literature (20% of all carotid body tumors). A 38-year-old female first visited Tokyo Metropolitan Fuchu Hospital in November, 1984, with the chief complaint of a non-tender mass on the left side of her neck. A CT scan revealed a high density area with a clear margin at the level of the left carotid bifurcation. An angiogram demonstrated a vascular-rich mass with slight widening of the carotid bifurcation. A diagnosis of left carotid body tumor was made preoperatively. The tumor(3.5×2.5×2.5cm)and two lymphnodes were resected by the subadventitial technique under general anesthesia.The diagnosis was malignant carotid body tumor with metastasis to the regional lymphnodes. Because of the discrepancy between the histological findings and the clinical course, malignancy was proved by the evidence of regional lymphnode metastasis, distant metastasis or invasion of the adjacent organs. We discuss the clinical difference between benign and malignant tumors and the possibility of malignant change induced by biopsy or partial resection. Lastly we stress the usefulness of the angiogram in the preoperative diagnosis and the importance of long term postoperative follow-up.