頸動脈小体腫瘍の1治験例—術中内シャントの一工夫と頸動脈小体腫瘍の組織学的検討

A Case of Carotid Body Tumor:A Device for Internal Shunt During Operation and Histopathological Examination of Carotid Body Tumor

　はじめに

　頸動脈小体（carotid body）は，頸動脈分岐部の後壁外膜内に位置し呼吸，脈拍，血圧などを調節する化学受容器（chemoreceptor）と考えられており，そこに発生する頸動脈小体腫瘍は比較的稀であり摘出に難渋する腫瘍とされている^1,2）。

　今回われわれは，左頸部無痛性腫瘤を主訴として来院した頸動脈小体腫瘍症例を経験，術中頸動脈バイパスとして簡単なシャントを工夫し，容易に全摘出することができた。今回得た腫瘍の免疫組織化学的所見を併せ，若干の考察を加えて報告する。

A 29-year-old woman presented with a 2-year history of having a painless and pulsating mass in the left side of the neck. Cranial nerve paralysis was not present. Enhanced CT demonstrated a hypervascular tumor with a clear margin surroun-ding the carotid bifurcation. Carotid angiogram demonstrated that the hypervascular tumor was located between the external and internal carotid arteries on the carotid bifurcation.

Resection of the tumor was performed under general anesthesia (GOF) using an internal shunt.

Internal shunt was conducted by two tubes for perfusion to the coronary artery, since blood flow in the tube was visible and the tube was hard to disconnect owing to the rim. An adhension bet-ween the tumor and carotid artery was found, but dissection in the capsular-adventitial plane was successfully performed after diversion of blood flow to the tumor.

Immunohistopathological study of the tumor revealed negative staining of S-100 protein and positive staining of NSE, and the presence of catecholamine was demonstrated by fluorescent histological examination.