Nakamura Kazuhiko, Osada Mikako, Goto Ayako, Iwasa Tsutomu, Takahashi Shunsuke, Takizawa Nobuyoshi, Akahoshi Kazuya, Ochiai Toshiaki, Nakamura Norimoto, Akiho Hirotada, Itaba Soichi, Harada Naohiko, Iju Moritomo, Tanaka Munehiro, Kubo Hiroaki, Somada Shinichi, Ihara Eikichi, Oda Yoshinao, Ito Tetsuhide, Takayanagi Ryoichi
a Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences , Kyushu University , Higashi-Ku , Fukuoka , Japan ;
b Department of Anatomic Pathology, Pathological Sciences, Graduate School of Medical Sciences , Kyushu University , Higashi-Ku , Fukuoka , Japan ;
Scand J Gastroenterol. 2016;51(4):448-55. doi: 10.3109/00365521.2015.1107752. Epub 2015 Nov 5.
Although the World Health Organisation (WHO) defined a novel classification of gastroenteropancreatic neuroendocrine tumours (NETs) in 2010, indications for endoscopic resection of rectal NETs in the guidelines were based on evidence accumulated for carcinoid tumours defined by a previous classification. This study was designed to clarify indications for endoscopic resection of rectal NETs corresponding to the new WHO classifications.
One hundred-seventy rectal NETs resected endoscopically from April 2001 to March 2012 were histologically re-classified according to the WHO 2010 criteria. The clinicopathological features of these lesions were analysed, and the short- and long-term outcomes of endoscopic resection were evaluated.
Of the 170 rectal NETs, 166 were histopathologically diagnosed as NET G1 and four as NET G2. Thirty-eight tumours (22.4%) were positive for lymphovascular invasion, a percentage higher than expected. Although the curative resection rate was low (65.3%), en bloc (98.8%) and complete (85.9%) resection rates were high. Modified endoscopic mucosal resection (88.0%) and endoscopic submucosal dissection (92.2%) resulted in significantly higher complete resection rates than conventional endoscopic mucosal resection (36.4%). No patient experienced tumour recurrence, despite the low curative resection rate.
Despite the low curative resection rate, prognosis after endoscopic resection of rectal NETs was excellent. Prospective large-scale, long-term studies are required to determine whether NET G2 and tumours >1 cm should be included in the indication for endoscopic resection and whether tumours with lymphovascular invasion can be followed up without additional surgery.
尽管世界卫生组织（WHO）在2010年对胃肠胰神经内分泌肿瘤（NETs）进行了新的分类，但指南中直肠NETs内镜切除的指征是基于先前分类所定义的类癌肿瘤积累的证据。本研究旨在明确与WHO新分类相对应的直肠NETs内镜切除的指征。
对2001年4月至2012年3月间内镜切除的170例直肠NETs进行组织学重新分类，依据WHO 2010标准进行分析。分析这些病变的临床病理特征，并评估内镜切除的短期和长期结果。
170例直肠NETs中，166例经组织病理学诊断为NET G1，4例为NET G2。38例肿瘤（22.4%）有脉管侵犯，高于预期比例。尽管根治性切除率较低（65.3%），但整块切除率（98.8%）和完整切除率（85.9%）较高。改良内镜黏膜切除术（88.0%）和内镜黏膜下剥离术（92.2%）的完整切除率显著高于传统内镜黏膜切除术（36.4%）。尽管根治性切除率较低，但无患者出现肿瘤复发。
尽管根治性切除率较低，但直肠NETs内镜切除后的预后良好。需要进行前瞻性大规模长期研究，以确定NET G2和直径>1 cm的肿瘤是否应纳入内镜切除指征，以及有脉管侵犯的肿瘤是否可以不进行额外手术而进行随访。
