多発食道表在癌の1例

Multiple Esophageal Superficial Cancer, Report of a Case

要旨　患者は69歳，男性で，切歯から26cmの右壁に褪色調で平坦な0-Ⅱc病変を認めた，トルイジンブルー・ヨード二重染色では境界明瞭なヨード不染となり，病変内の一部がトルイジンブルーで淡染したが，濃染部はなく深達度M1と診断した．一方，切歯より32cmの左壁に発赤調で境界明瞭な陥凹性病変を認めた．陥凹面はやや不整でトルイジンブルー・ヨード二重染色にて，病変部は境界明瞭なヨード不染を呈した．空気少量では畳目模様の出現も認め，深達度Tis（M1）の0-Ⅱc型食道表在癌と診断した．EMRの結果両者とも深達度Tis（M1）の同時多発食道表在癌であった．食道表在癌は多発傾向があり，1992年から2000年までに佐久総合病院で診断治療した食道表在癌85例中12例（14.1％）が同時多発であった．したがって，1つの食道表在癌を発見した場合には同時多発癌の存在を念頭に置き，全食道のヨード染色観察を要する．

　A 69-year-old-man came to our hospital to investigate suspicious of esophageal cancer. Esophagoscopy revealed two lesions. One was a shallow, depressed red lesion at the lower thoracic esophagus, the surface being slightly irregular. This depressed lesion was stained not by iodine but weakly and focally by toluidine blue, so we diagnosed the invasion depth as M1 or 2 (Fig.1～4).

　The other was a shallow, depressed lesion at the middle thoracic esophagus and the surface was flat and slightly red. The depressed lesion was stained by neitter iodine nor toluidine blue, so we diagnosed the invasion depth as Tis (M1) (Fig.5～8).

　Intra-ductal ultrasonography revealed a normal wall structure and no lymph nodal metastasis (Fig.9).

　The lesions were treated by endoscopic mucosal resection, using the Hooking EMR method. The resected specimens were shallow, depressed lesions without marginal elevation. The margin became clearer after iodine staining. More precise pathologic observation can be made with an en-bloc resected EMR specimen (Fig.10～13).

　The histological diagnosis was two squamous cell carcinomas limited to the mucosal layer, with neither lymphatic nor venous invasion. The tumors were 17×12 and 17×15 mm in area (Fig.14,15).

　We performed esophageal EMR for 85 cases from 1992 to 2000 and 12 cases (14.1％) had multiple esophageal cancer. When esophageal cancer is found, further observation of the esophageal lumen should be carried out in case there is another lesion present.