胃型腺癌にEMRを施行した1例

Gastric Adenocarcinoma Resected by EMR, Report of a Case

要旨　患者は75歳，女性．胃角部前壁から小彎にかけて4cm大のⅡa病変を有しており，生検で胃型の高分化型腺癌が証明された．本症例は，範囲がやや不明瞭なことと大きさを考慮して外科手術を勧めたが，拒絶されたため内視鏡的粘膜切除術（endoscopic mucosal resection；EMR）を施行した．断端陽性のため再EMRを施行し，肉眼的には切除しえたと考えたが経過観察内視鏡でEMR後の綴痕部から印環細胞癌が証明され，最終的に外科切除となった．切除標本の組織学的検討で，14cm大の胃型の極めて高分化型Ⅱb病変の拡がりと一部に印環細胞癌の成分の存在が確認された。胃型胃癌はしばしば粘膜表層を進展し，範囲が非常にわかりづらい場合があること，未分化型癌の混在が特徴とされており，近年広く施行されるようになったEMRに際しては組織型をも考慮し，慎重に行うべきと考えさせられる症例であった．

　A 75-year-old female was diagnosed as having early gastric cancer, Ⅱa, gastric type in histology. Its estimated size was 40 mm in diameter. We evaluated her condition and judged that she was not a candidate wellsuited for endoscopic mucosal resection (EMR) and recommended that she undergo a surgical operation. She refused it strongly, so we performed EMR twice. Because biopsy specimens from EMR scar revealed signet-ring cell carcinoma on follow-up endoscopic examination, she finally accepted surgical treatment. The size of the cancer was 14 cm in diameter and it was larger than had been expected. Immunohistochemical staining revealed gastric-type mucous. Sometimes, gastric type early gastric cancer has an unclear margin and consists of signet-ring cell carcinoma and poorly differentiated adenocarcinoma. We must evaluate carefully the indication for EMR in early gastric cancer, gastric type, based on findings such as these.