ERCP，USならびにEUSによる胆囊癌の進展度診断

The Diagnosis of Spread of Gallbladder Carcinoma by ERCP, US and Endoscopic Ultrasonogram

要旨　早期胆囊癌の診断がここ数年大きな論議を呼んでいるが，病理の立場からⅡb型の表面型早期癌が少なくないことが指摘されるようになり，早期胆囊癌の診断の難しさが痛感される．一方，胆囊癌の進展度診断は治療法の選択や予後を大きく規定することから大きな意義を有している．筆者らは胆囊癌の進展度診断をERCPとUSによる癌深達度，肝床浸潤，胆管浸潤の3点で診断能を検討した．ERCPやUSによる癌深達度診断は平坦型を含めた限局性隆起性病変ではpmまでにとどまることが多かったが，一部ssの癌も含まれた．また，ERCPで胆管像を十分に描出することにより，胆管浸潤は把握できたが，肝床への癌の進展はERCPでもUSでも読み取ることは難しかった．したがって胆囊癌の深達度および進展度診断に有用な新しい検査法が必要である．教室では超音波内視鏡を用いて進展度診断を検討しているが，本検査法では胆囊病変ならびに胆囊壁の層構造が詳細に描出できることから，癌深達度，胆管浸潤，肝床浸潤の診断に大変有用であった．

　Recently, the early diagnosis of gallbladder cancer has been often discussed in our country. However, the diagnosis of Ⅱb type of early gallbladder cancer has not yet been confirmed. On the other hand, the diagnosis of the spread of this disease is most important, because the choice of treatment method and the prognosis is best determined by the spread of the cancer.

　By ERCP and US findings, we have investigated retrospectively the spread of gallbladder cancer. ERCP and US were useful in the diagnosis of infiltration depth of cancer and cancer invasion of the biliary tract. However, the diagnosis of cancer invasion of the liver bed could not be clarified by ERCP or US.

　Endoscopic ultrasonogram (EUS), the most newly developed diagnostic method in our institution, has been able to demonstrate gallbladder lesions and gallbladder wall conditions more clearly than the other imaging diagnostic procedures. Therefore, EUS was highly appreciated as a method for diagnosing infiltration depth and spread of gallbladder cancer.