治療成績からみた食道m3・sm癌の治療方針―EMR＋αの治療成績：m3・sm1癌を中心に

Treatment Strategy of m3 and sm1 Esophageal Cancer Based on the Clinical Results of Endoscopic Resection Associated with Adjuvant Treatments

要旨　1990年より2004年12月までにEMRを施行した臨床診断N0のm₃・sm₁食道癌81例（m₃：58例，sm₁：23例）を検討対象とした，EMR後の追加治療は，全身状態と深達度，浸潤長径，脈管侵襲，浸潤様式，先進部の組織型などの組織所見を参考に施行した．①経過観察57例70％（m₃：49例，sm₁：8例），②放射線化学療法（CRT）または放射線治療（RT）17例21％（m₃：7例，sm₁：10例），③化学療法3例4％（m₃：2例，sm₁：1例），④手術療法4例5％（m₃：0例，sm₁：4例）であった．内視鏡病型は，経過観察m₃癌の96％は凹凸が目立たない0-II型であったが，他は陥凹が目立ち，陥凹内あるいは陥凹周囲に盛り上がりを伴う0-IIc病変が大半を占めた．治療法別に脈管侵襲陽性率を見ると，経過観察m₃癌19％，sm₁癌50％，CRT/RT例m₃癌42.9％，sm₁癌70％，化学療法例m₃・sm₁癌は100％，手術例sm₁癌75％であった．局所再発は，経過観察m₃癌8例（16％）に認め，7例は再EMR，1例は再EMR＋RTを行った．リンパ節転移は5例あり，①経過観察m₃癌，0-IIa＋IIc型のly₀，v₀であり，EMR後3年目に106rRに再発し，現在CRT中，②化学療法m₃癌，0-IIa＋IIc型のly（＋），v（＋）であり，EMR後4年目上縦隔リンパ節転移が診断され，再発後11か月目に原病死，③化学療法sm₁癌，全周性の表層拡大型症例でly（＋），v（＋）であり，EMR後1.5年目に上縦隔のリンパ節転移が発見され，リンパ節摘出後CRTを施行し，追加治療後4年5か月CRを維持，④手術治療2例で106rRに転移を認めた．いずれも脈管侵襲陽性例であり，外科治療後，健在である．

　Treatment strategy for m₃ and sm₁ esophageal cancer was studied by observing the clinical result in 81 patients (m₃ : 58 and sm₁ : 23) who had pathologically proved m₃ and sm₁ esophageal cancer and underwent endoscopic treatment using mucosal resection (EMR) or endoscopic submucosal dissection (ESD), from 1990 to 2004. Additional treatments after EMR or ESD were decided considering the general condition of the patients and pathological findings such as the depth of cancer invasion, the size of m₃ invasion, the micro-vascular permeation and the mode of invasion. No adjuvant treatment was employed in 70％ of all patients (m₃ : 49 and sm₁ : 8) because they showed a very low incidence of micro vascular permeation. Radiation or chemoradiation (21％ of all cases), chemotherapy (4％) and radical esophagectomy (4％) were employed for patients with pathological findings of micro vascular permeation. Five patients (6.2％ of all cases : 3.4％ of all m₃ and 13％ of sm₁) developed lymph node recurrence and one patient died (1.7％ of all patients). Considering the above facts, the indication for additional treatments after endoscopic resection of m₃ and sm₁ esophageal cancer is probably decided on clinico pathological findings. 1) In cases with superficial esophageal cancer with simple type 0-IIc, they probably have shallow invasion reaching only to the muscularis mucosae (m₃) and they seldom show micro vascular permeation. For such cases, no additional treatment is recommended after EMR or ESD. 2) In cases with superficial esophageal cancer with mixed type or with type 0-III cancers, adjuvant treatments are recommended because of their high incidence of deep m₃ invasion and micro vascular invasion.