Saito Tomoya, Kobayashi Kiyonori, Sada Miwa, Matsumoto Yasuhiro, Mukae Miyuki, Kawagishi Kana, Yokoyama Kaoru, Koizumi Wasaburo, Saegusa Makoto, Murakami Yoshitaka
Department of Gastroenterology, Kitasato University, School of Medicine, Sagamihara, Japan.
Research and Development Center for New Medical Frontiers, Kitasato University, School of Medicine, Sagamihara, Japan.
J Anus Rectum Colon. 2019 Oct 30;3(4):152-159. doi: 10.23922/jarc.2018-036. eCollection 2019.
Colorectal laterally spreading tumors (LSTs) are widely recognized owing to their structural characteristics. This study aims to clarify the histopathological characteristics of large colorectal LSTs according to growth pattern.
We studied 297 colorectal LSTs measuring ≥20 mm in diameter. The LSTs were classified into four types: granular homogenous type (LST-G-H), granular nodular mixed type (LST-G-M), non-granular flat elevated type (LST-NG-F), and non-granular pseudo-depressed type (LST-NG-PD). Retrospectively collected data were examined to compare the histopathological characteristics of LSTs according to the growth pattern.
LST-G-M lesions (142 lesions) were most common, followed by LST-NG-F (74 lesions), LST-G-H (61 lesions), and LST-NG-PD (20 lesions). The mean tumor diameter of LST-G lesions (38.5 ± 17.2 mm) was significantly greater than that of LST-NG lesions (26.3 ± 7.0 mm, < 0.001). In particular, 45% of LST-G-M lesions were ≥40 mm in diameter. Adenomas accounted for 54% of LST-G-H lesions compared with only 10% of LST-NG-PD lesions. Pathological T1 carcinomas accounted for 55% of LST-NG-PD lesions and were not found among LST-G-H lesions.
The biological malignancy of colorectal LSTs differs considerably depending on the growth pattern even among large lesions and therefore should be considered when selecting treatment regimens.
结直肠侧向发育型肿瘤（LSTs）因其结构特征而被广泛认知。本研究旨在根据生长模式阐明大肠大型LSTs的组织病理学特征。
我们研究了297例直径≥20mm的结直肠LSTs。这些LSTs被分为四种类型：颗粒均匀型（LST-G-H）、颗粒结节混合型（LST-G-M）、非颗粒扁平隆起型（LST-NG-F）和非颗粒假凹陷型（LST-NG-PD）。回顾性收集数据，以比较不同生长模式的LSTs的组织病理学特征。
LST-G-M病变（142例）最为常见，其次是LST-NG-F（74例）、LST-G-H（61例）和LST-NG-PD（20例）。LST-G病变的平均肿瘤直径（38.5±17.2mm）显著大于LST-NG病变（26.3±7.0mm，<0.001）。特别是，45%的LST-G-M病变直径≥40mm。腺瘤在LST-G-H病变中占54%，而在LST-NG-PD病变中仅占10%。病理T1期癌在LST-NG-PD病变中占55%，而在LST-G-H病变中未发现。
即使在大型病变中，结直肠LSTs的生物学恶性程度也因生长模式的不同而有很大差异，因此在选择治疗方案时应予以考虑。
