Saitoh Yusuke, Inaba Yuhei, Sasaki Takahiro, Sugiyama Ryuji, Sukegawa Ryuji, Fujiya Mikihiro
Digestive Disease Center, Asahikawa City Hospital, Japan.
Division of Gastroenterology and Hematology/Oncology, Department of Internal Medicine, Asahikawa Medical University, Asahikawa, Japan.
Dig Endosc. 2016 Apr;28(3):324-9. doi: 10.1111/den.12503. Epub 2015 Sep 6.
As a result of recent advances in endoscopic therapeutic technology, the number of endoscopic resections carried out in the treatment of early colorectal carcinomas with little risk of lymph node metastasis has increased. There are no reports of lymph node metastasis in intramucosal (Tis) carcinomas, whereas lymph node metastasis occurs in 6.8-17.8% of submucosal (T1) carcinomas. Three clinical guidelines have been published in Japan and the management strategy for early colorectal tumors has been demonstrated. According to the 2014 Japanese Society for Cancer of the Colon and Rectum (JSCCR) Guidelines for the Treatment of Colorectal Cancer, additional surgery should be done in cases of endoscopically resected T1 carcinoma with a histologically diagnosed positive vertical margin. Additional surgery may also be considered when one of the following histological findings is detected: (i) SM invasion depth ≥1000 µm; (ii) histological type por., sig., or muc.; (iii) grade 2-3 tumor budding; and (iv) positive vascular permeation. A resected lesion that is histologically diagnosed as a T1 carcinoma without any of the above-mentioned findings can be followed up without additional surgery. As for the prognosis of endoscopically resected T1 carcinomas, the relapse ratio of approximately 3.4% (44/1312) is relatively low. However, relapse is associated with a poor prognosis, with 72 cancer-related deaths reported out of 134 relapsed cases (54%). A more detailed stratification of the lymph node metastasis risk after endoscopic resection for T1 carcinomas and the prognosis of relapsed cases will be elucidated through prospective studies. Thereafter, the appropriate indications and safe and secure endoscopic resection for T1 carcinomas will be established.
由于内镜治疗技术的最新进展，在治疗早期结直肠癌且淋巴结转移风险较小的情况下，进行内镜切除的数量有所增加。黏膜内（Tis）癌尚无淋巴结转移的报道，而黏膜下（T1）癌的淋巴结转移发生率为6.8%-17.8%。日本已发布三项临床指南，并阐明了早期结直肠肿瘤的管理策略。根据2014年日本结直肠癌学会（JSCCR）结直肠癌治疗指南，对于内镜切除的T1癌且组织学诊断垂直切缘阳性的病例，应进行额外手术。当检测到以下任何一种组织学表现时，也可考虑额外手术：（i）黏膜下浸润深度≥1000 µm；（ii）组织学类型为低分化、印戒细胞或黏液型；（iii）肿瘤芽生分级为2-3级；（iv）血管侵犯阳性。经组织学诊断为T1癌且无上述任何表现的切除病变可进行随访，无需额外手术。至于内镜切除的T1癌的预后，复发率约为3.4%（44/1312），相对较低。然而，复发与预后不良相关，在134例复发病例中有72例（54%）报告死于癌症。通过前瞻性研究将阐明T1癌内镜切除后淋巴结转移风险的更详细分层以及复发病例的预后。此后，将确定T1癌的适当适应证以及安全可靠的内镜切除方法。
