m3・sm1食道癌に対するEMRの可能性

Possibility of Endoscopic Mucosal Resection in Patients with m3 and sm1 Esophageal Cancer

要旨　m₃・sm₁食道癌は10～15％程度のリンパ節転移率を有する．逆にみれば85％の症例にはリンパ節転移は認められず，内視鏡的粘膜切除術(EMR)の適応となるものも多いと考えられる．われわれの施設では101例のm₃・sm₁食道癌のうち55例(54.5％)にEMRを適応している．m₃・sm₁食道癌のEMRの適応から除かれるのは，①0Ⅱc＋Ⅱa型，0-Ⅲ型，加えて0-Ⅰ型，②その他の病型のうち，長径5cm以上のもの，全周性のもの．この群に全体の31.7％の症例が含まれ，リンパ節転移を有する例の72.7％が含まれる．残りの症例にEMRを施行し，①ly(＋)のもの，②infγのもの，③低分化型のもの，に引き続き外科的切除術を適応する．これで，全体の50.5％が外科的切除術で，49.5％がEMRで治療され，リンパ節転移に関するspecificityは100％となる．

　Patients with m₃・sm₁ esophageal cancer have lymph node metastasis at the rate of 10～15%. However, more than 85% of the patients have no lymph node metastasis. For these patients endoscopic mucosal resection (EMR) is indicated as the most suitable treatment. Of 101 cases of m₃・sm₁ esophageal cancers treated in our institution, EMR was indicated as the treatment of choice in 55 cases (54.5%). Because of the high rate of lymph node metastasis EMR should be avoided in the following cases: (1) 0-Ⅱc ＋ Ⅱa type, 0-Ⅲ type, and 0-Ⅰ type. (2) Lesions of which the diameter is more than 5 cm, or which occupy the whole circumference of the esophageal lumen. Among these patients, 31.7% of (1) and (2) cases had lymph node involvement, and 72.7% of the m₃・sm₁ cases with lymph node metastasis were involved in this group. In cases other than these, EMR is indicated as a first step, but after pathological examination of resected specimens is performed, those patients with (1) lymph vessels invasion〔ly(＋)〕, and (2) infγ, (3) poorly differentiated squamous carcinomas, should recieve radical surgical treatment continuously. On our study, 49.5% of all m₃・sm₁ esophageal cancer cases were treated with EMR and the remaining 50.5% of the patients were treated with radical surgical treatment.

　As for the patients with lymph node metastasis radical surgery is indicated in 100% of the cases.