食道m1・m2癌EMR後の長期成績

Clinical Outcome of Endoscopic Mucosal Resection for m1・m2 Esophageal Cancer

要旨　1989年12月から2005年3月まで食道扁平上皮癌でEMRを行ったm₁・m₂食道癌214例238病巣，m₁：140病巣，m₂：98病巣（男：女＝189：25，平均年齢66.4歳）を対象とし，長期成績を検討した．同時多発癌は21例（9.8％）45病巣に認めた．局所再発は19例（8.9％）に認め，手術が1例，放射線治療が2例，内視鏡治療が16例に行われた．異時多発癌は22例（10.3％）に認め，すべて内視鏡治療により制御された．リンパ節転移，遠隔臓器再発はなかった．他臓器重複癌を72例（33.6％）に認めた．原病死はなく，他病死15例，他癌死16例で食道癌より後発の他臓器癌死を9例に認めた．over allで5年生存率93％，10年生存率70％であった．長期的にみても，食道m₁・m₂癌は十分内視鏡治療で根治が望め，異時多発病巣や他臓器重複癌の発見には10年を超える長期的な経過観察が必要である．

　Endoscopic mucosal resection (EMR) has become a standard therapy for early esophageal cancer that is confined to the mucosa (m₁:invaded to the epithelium, m₂:invaded to the lamina propria mucosae), without lymph node metastasis.

　We reviewed our clinical experience regarding EMR for the treatment of m₁・m₂ esophageal cancer in 214 patients with 238 lesions (m₁＝140, m₂＝98) between December, 1989 and March, 2005. Among them, synchronous multiple primary cancers were found in 21 cases (9.8％).

　Local recurrence of the disease after EMR was detected in 19 cases (8.9％). The median time to local recurrence after EMR was 12 months (range 3～33 months). Of the 19 patients with recurrent lesions, 16 underwent endoscopic treatment. Among the remaining 3 patients, 2 patients were treated with radiotherapy, while 1 patient was operated on. Neither lymph node metastases nor distant metastases were identified.

　Metachronous multiple primary cancers were found in 22 cases (10.3％). The median time needed to detect metachronous multiple primary cancers after EMR was 38 months (range 14～144 months). All of the patients were cured by endoscopic treatment.

　In 72 cases (33.6％), out of a total of 214 cases treated by EMR for m₁・m₂ esophageal cancer, cancer also occurred in organs other than the esophagus. The median time needed to detect metachronous cancer, occurring in organs other than the esophagus, was 58 months (range 18～133 months) after EMR. At a median follow-up of 9 years, death occurred in 31 cases. 15 patients died as a result of other diseases, 16 patients died of other carcinomas, but no one died of esophageal carcinoma. 9 patients died of metachronous cancer occurring in organs other than the esophagus. The overall survival rate at 5 years was 93％, and at 10 years the survival rate was 70％.

　Most of the m₁・m₂ esophageal cancers were cured by EMR. However, in order to detect both metachronous multiple primary cancers and the cancers occurring in organs other than the esophagus, patients with esophageal cancer should therefore be carefully followed up for 10 years after the diagnosis of esophageal cancer.