早期胃癌に対する内視鏡的切除術―根治を目ざして

Endoscopic Resection: For the Purpose of a Curative Treatment of Early Gastric Cancer

要旨　内視鏡的切除術（以下ER）は切除標本の病理組織学的検索が可能なことから，症例を吟味すれば早期胃癌の根治治療として期待できる．すなわち，ERは縮小手術のうち最も侵襲の少ない術式と位置づけることもできる．根治を目的としたERの適応について当教室で過去6年間に経験した早期胃癌48例50病変，腺腫31例33病変を対象に検討した．断端陰性を，①単回のER標本であり，①切除標本を2mm間隔で切り出し組織学的に断端に正常腺管がみられること，と定義すると，83病変中38病変（45.7％）が断端陰性であり，これらの病変ではER後の胃切除術や経過観察で遺残がみられず治癒切除と考えられた．断端陰性例の病巣の大きさ，占居部位，Ulの有無をretrospectiveに検討すると，10mm以下，Ul(－)，前庭部または体部大彎の粘膜内の病変が根治目的としてよい適応であった．断端陽性例で外科的手術を行った6例においては，1例を除いてすべて遺残が認められた．したがって，断端陽性となるような症例は単回ERを根治の条件とすると適応にはならないと考えられる．

　Endoscopic resection (ER) can be a curative treatment of early gastric cancer in selected patients because resected specimens can be histologically examined. ER may be regarded as the least invasive modality of curative surgeries. To investigate the indications for ER as a curative treatment of early gastric cancer, we analyzed retrospectively 48 patients (50 lesions) of early gastric cancer and 31 patients (33 lesions) of gastric adenoma who underwent ER in our department over the last 6 years. Resected specimens were histologically examined at 2mm intervals. A case without cancer cells on the surface of a cutting edge was designated as a stump negative case. Thirty eight out of 83 1esions (45.7%) were stump negative. In these cases, no residual lesions were found on the follow-up endoscopic examinations or the resected specimen if a gastrostomy was performed thereafter. Thus, a negative stump may indicate that ER can be a curative procedure for early gastric cancer. Analysis of factors which affected negativity of tumor cells at a cutting edge showed that the indications for ER were as follows: lesions less than 10mm in size, lesions without ulcerations, and mucosal lesions in the antrum or at the greater curvature. Five out of six stump positive pabents who subsequently underwent surgery had residual lesions in the resected specimens. Therefore, ER should not be regarded as a curative treatment on a positive stump case.