食道扁平上皮癌に対するESDの成績―T1a-MM，SM1を中心に

Prognosis of Esophageal Squamous Cell Carcinoma Treated by Endoscopic Submucosal Dissection

要旨　2000年1月から2006年12月までにESDが施行された食道扁平上皮癌158例180病変のうち，深達度T1a-MM 28例とT1b（SM1）12例を症例を対象とした．一括完全切除率はT1a-MM 癌96.4％，T1b（SM1）癌83.3％であった．T1a-MM癌28例中5例（17.9％）にリンパ管侵襲を認め，2例にCRTが追加施行され，他の3例は経過観察された．CRTが施行された2例は無再発，経過観察3例中1例はリンパ節転移が生じたが他病死，他の2例には再発を認めなかった．一方，ly陰性のT1a-MM癌23例にリンパ節再発例はなかった．SM1癌12例中4例（33.3％）にリンパ管侵襲を認め，2例にはCRTが追加施行され，2例は経過観察された．CRTの2例は無再発，経過観察2例中1例は2年5か月後に現病死，他の1例は無再発のまま他病死した．ly陰性SM1癌8例中4例にCRTを施行し，4例は経過観察されたが，この群にリンパ節再発はなかった．T1a-MMやT1b（SM1）の食道SCCに対しても安全にESDを施行することは可能であり，臨床的に転移がない場合はESDによる一括完全切除を施行し，追加治療の要否を判定すべきと思われた．

　158 patients who had esophageal squamous cell carcinoma（SCC）were treated by endoscopic submucosal dissection（ESD）from Jan. 2,000 to Dec. 2006. The invasion depth was divided as epithelium（EP）,Lamina propria mucosa（LPM）, musucularis mucosa（MM）and submuosal layer. When the depth of submucosal invasion was 200 micrometers or less, the invasion depth was defined as SM1.

　In this study, out of 158 patients 28 patients had MM SCC, and 12 patients had SM1 SCC. The additional therapies such as Esophagectomy or Chemo Radio Therapy（CRT）were recommended to the patients, when lymphatic permeation was found.

　Among the patients who had MM SCC,5 patients had lymphatic permeation. Among the patients who had SM1 SCC,4 patients had lymphatic permeation. 2 MM and 2 SM1 patients were treated by CRT and the other 5 patients who had lymphatic permeation refused the additional therapy because of other diseases. All 4 patients who were treated by CRT are alive, but lymph node metastasis was found in 2 of the patients who refused CRT. One died of esophageal SCC, and one died of another disease. No lymph node metastasis was found in 23 patients who had MM without lymphatic permeation, and 8 patients who had SM1 without lymphatic permeation. According to our data, the indication of esophageal ESD could be expanded for MM or SM1 SCC without lymphatic permeation.