Radiosurgeryを併用した，頸静脈孔腫瘍の新しい治療戦略

A New Strategy for the Treatment of Jugular Foramen Tumors Using Radiosurgery

I．はじめに

　頸静脈孔には，その部を発生母地とするグロームス腫瘍，下位脳神経神経鞘腫の他に，この部に進展を示す髄膜腫，epidermoid cyst，転移性腫瘍などがある．転移性病疫を除けば大半は良性腫瘍であり，それらの治療の基本は手術的摘出にある．しかし，頭蓋底部より頸部に移行する下位脳神経群，頸静脈，頸動脈などが錯走する解剖学的特色の他に，同部の腫瘍がしばしば後頭蓋窩，頸部の両方向に進展する特性から，手術的摘出は必ずしも容易ではない．近年，頭蓋内良性腫瘍，特に聴神経腫瘍^4）），髄膜腫^8,10）に対するradiosurgeryの良好な治療成績が報告されている．本法は，頸静脈孔の腫瘍群にも応用できる可能性があると考え，ガンマナイフを利用した治療法を試みたので，その結果を報告する．

A new treatment strategy for jugular foramen tumors using radiosurgery is reported. Six jugular foramen tumors, including 2 glomus tumors and 4 lower cranial neurinomas, were involved. Among them only one tumor was confined in the jugular foramen, but the others extended into the posterior fossa, the upper cer-vical portion or both. As an initial treatment, 3 cases underwent operative resection from suboccipital or transcervical route. The tumor sizes at radiosurgery ranged from 14.3 to 36.1 mm with a mean of 22.4 mm in diameter. They were treated with a marginal close between 13 to 16.5 Gy (mean 15.6 Gy). Follow.up MRI showed an apparent tumor shrinkage in 4 and no change in 2. Central tumor necrosis was found in 4 cases, but tumor progression was never observed in the mean follow-up period of 19 months. No complication occurred during and after the radiosurgery. These re-sults indicate that radiosurgery is effective for the con-trol of jugular formen tumors with acceptable risk. Large tumors extending to the upper cervical portion and posterior fossa can be treated by operative resec-tion combined with radiosurgery.