脳腫瘍に対する内頸動脈内ACNU持続投与とPhenobarbitalの併用療法

Treatment of Brain Tumor with Phenobarbital and Continuous Infusion of ACNU into Internal Carotid Artery

I．はじめに

　nitrosourea系抗癌剤は血液脳関門を通過するので脳腫瘍に有効であるといわれている^3,8）．しかし造血系に対する強い副作用のため投与量に限界があるのが現状かと思われる^1）．

　最近，nitrosourea系抗癌剤にphenobarbital（PB）を併用すれば，その代謝が亢進され血中濃度が下がり，その結果，腫瘍に対する効果が減弱するという報告が散見されるようになってきた^5）．このPBの効果は，同時に副作用をも弱めうる可能性も示唆するものと考えられる．

ACNU is well known to be an effective chemotherapeu-tic agent for brain tumor. It also has a strong toxicity tobone marrow. Recently phenobarbital (PB) was reportedto reduce the toxicity of ACNU by induction of hepaticmicrosomal enzyme which is related to the metabolism ofACNU, and possible effect of PB to protect bone marrowsuppression was suggested. Indeed the toxicity to bonemarrow may be reduced by administration of PB, but tumor-cidal effect of ACNU also becomes poorer because PBinduces the lower concentration of ACNU in the cir-culation around the tumor as well as that of general cir-culation.