Anderson Joseph C
Department of Veterans Affairs Medical Center, White River Junction, VT, and The Geisel School of Medicine at Dartmouth Medical, Hanover, NH, USA.
Gut Liver. 2014 Nov;8(6):582-9. doi: 10.5009/gnl14248. Epub 2014 Nov 15.
Hyperplastic or serrated polyps were once believed to have little to no clinical significance. A subset of these polyps are now considered to be precursors to colorectal cancers (CRC) in the serrated pathway that may account for at least 15% of all tumors. The serrated pathway is distinct from the two other CRC pathways and involves an epigenetic hypermethylation mechanism of CpG islands within promoter regions of tumor suppressor genes. This process results in the formation of CpG island methylator phenotype tumors. Serrated polyps are divided into hyperplastic polyps, sessile serrated adenomas/polyps (SSA/Ps), and traditional serrated adenomas (TSAs). The SSA/P and the TSA have the potential for dysplasia and subsequent malignant transformation. The SSA/Ps are more common and are more likely to be flat than TSAs. Their flat morphology may make them difficult to detect and thus explain the variation in detection rates among endoscopists. Challenges for endoscopists also include the difficulty in pathological interpretation as well surveillance of these lesions. Furthermore, serrated polyps may be inadequately resected by endoscopists. Thus, it is not surprising that the serrated pathway has been linked with interval cancers. This review will provide the physician or clinician with the knowledge to manage patients with serrated polyps.
增生性或锯齿状息肉曾被认为几乎没有临床意义。现在，这些息肉中的一部分被认为是锯齿状途径中结直肠癌（CRC）的前体，该途径可能占所有肿瘤的至少15%。锯齿状途径不同于其他两种CRC途径，涉及肿瘤抑制基因启动子区域内CpG岛的表观遗传高甲基化机制。这一过程导致CpG岛甲基化表型肿瘤的形成。锯齿状息肉分为增生性息肉、无蒂锯齿状腺瘤/息肉（SSA/P）和传统锯齿状腺瘤（TSA）。SSA/P和TSA有发育异常及随后发生恶性转化的可能。SSA/P更常见，且比TSA更可能是扁平的。它们的扁平形态可能使其难以检测到，从而解释了内镜医师检测率的差异。内镜医师面临的挑战还包括这些病变的病理解释困难以及监测困难。此外，内镜医师可能无法充分切除锯齿状息肉。因此，锯齿状途径与间隔期癌症有关也就不足为奇了。本综述将为医生或临床医生提供管理锯齿状息肉患者的知识。
