Mizuguchi Yasuhiko, Tanaka Yusaku, Cho Hourin, Sekiguchi Masau, Takamaru Hiroyuki, Yamada Masayoshi, Sakamoto Taku, Matsuda Takahisa, Hashimoto Taiki, Sekine Shigeki, Saito Yutaka
Endoscopy Division, National Cancer Center Hospital, Tokyo, Japan.
Division of Diagnostic Pathology, National Cancer Center Hospital, Tokyo, Japan.
Dig Endosc. 2022 Jan;34(1):153-162. doi: 10.1111/den.13992. Epub 2021 May 24.
Superficially serrated adenoma (SuSA) is a recently proposed subtype of colorectal serrated lesions. It is characterized by distinct clinicopathological and molecular features, including mixed serrated and adenomatous histology and frequent genetic alterations involving KRAS and RSPO. This study aimed to characterize the endoscopic features of isolated and traditional serrated adenoma (TSA)-associated SuSAs.
We retrospectively evaluated the endoscopic findings of 25 isolated SuSAs and 21 TSA-associated SuSAs that were histologically and molecularly characterized.
SuSAs appeared as a sessile polyp or slightly elevated lesion located mostly in the sigmoid colon and rectum (88%). The size was between 3 and 20 mm (median, 6 mm). Most of them exhibited KRAS mutations (96%) and RSPO fusions/overexpression (92%). Endoscopically, many lesions had a whitish color (84%), a distinct border (96%), an irregular border (76%), and a lobulated surface (72%). However, diminutive lesions exhibited overlapping features with hyperplastic polyps. On narrow-band imaging, vessel patterns were invisible or appeared as lacy microvessels in most lesions (80%). Chromoendoscopy invariably showed stellar or elongated/branched stellar pits, indicating a serrated microarchitecture. Most TSA-associated SuSAs typically presented as polyps with a two-tier raised appearance, consisting of whitish lower and reddish higher components corresponding to a SuSA and a TSA, respectively.
SuSAs exhibit several characteristic endoscopic features on white-light and image-enhanced endoscopy. Diminutive lesions exhibit endoscopic features overlapping with hyperplastic polyps. Nonetheless, the endoscopic diagnosis of larger and TSA-associated SuSAs may be feasible.
浅表锯齿状腺瘤（SuSA）是最近提出的一种结直肠锯齿状病变亚型。其特征在于独特的临床病理和分子特征，包括混合性锯齿状和腺瘤样组织学以及涉及KRAS和RSPO的频繁基因改变。本研究旨在描述孤立性和传统锯齿状腺瘤（TSA）相关的SuSA的内镜特征。
我们回顾性评估了25例孤立性SuSA和21例TSA相关的SuSA的内镜检查结果，这些病例均进行了组织学和分子特征分析。
SuSA表现为无蒂息肉或轻度隆起病变，大多位于乙状结肠和直肠（88%）。大小在3至20毫米之间（中位数为6毫米）。大多数病例表现出KRAS突变（96%）和RSPO融合/过表达（92%）。在内镜下，许多病变呈白色（84%），边界清晰（96%），边界不规则（76%），表面呈分叶状（72%）。然而，微小病变与增生性息肉具有重叠特征。在窄带成像中，大多数病变（80%）的血管形态不可见或表现为花边状微血管。色素内镜检查总是显示星状或细长/分支状星状凹陷，表明存在锯齿状微结构。大多数TSA相关的SuSA通常表现为具有两层隆起外观的息肉，分别由对应于SuSA的白色下层和对应于TSA的红色上层组成。
SuSA在白光和图像增强内镜检查中表现出一些特征性内镜特征。微小病变的内镜特征与增生性息肉重叠。尽管如此，对较大的和TSA相关的SuSA进行内镜诊断可能是可行的。
