{"title":"Discrete immunohistochemical and clinicopathological features of serrated adenocarcinoma between the proximal and distal colon.","authors":"Naoki Tsugawa, Eiji Kamba, Takashi Murakami, Yudai Otsuki, Kei Nomura, Yuichiro Kadomatsu, Hirofumi Fukushima, Kiichi Sugimoto, Tsuyoshi Saito, Tomoyoshi Shibuya, Takashi Yao, Akihito Nagahara","doi":"10.1159/000548705","DOIUrl":null,"url":null,"abstract":"<p><strong>Introduction: </strong>Colorectal serrated adenocarcinoma (SAC), a subtype of colorectal adenocarcinoma determined histologically, has characteristics of epithelial serrations. Here, we examined the immunohistochemical and clinicopathological characteristics of colorectal SAC.</p><p><strong>Methods: </strong>Thirty-three specimens, pathologically diagnosed as SAC in our hospital between 2013-2022, were collected for immunohistochemistry of MLH1/MUC2/MUC5AC/p53, and sequencing of BRAF/KRAS mutations.</p><p><strong>Results: </strong>The proximal colon contained 25 lesions and the distal colon had 8. Patients with proximal SACs were predominantly female, whereas those exhibiting distal SACs were predominantly male (P = 0.003). Overall, lymph node and distant metastasis were present in 17 (52%) and 11 (33%) cases, respectively, with no significant differences between the proximal and distal groups. MLH1 expression loss was more frequent in proximal cases (40%) than distal SACs (13%). Most cases (97%) were MUC2+. MUC5AC+ was significantly more frequent in proximal cases (92%) than distal SACs (37%, P = 0.004). Significantly less p53 overexpression was present in proximal cases (40%) vs distal SACs (75%). Genetically, the 12 cases of SAC harboring BRAF mutations were all located in the proximal colon, with a significantly greater frequency (P = 0.030) whereas more frequent KRAS mutations were noted in distal SACs. Throughout 5 years of follow-up, three patients (two proximal SAC cases; one distal SAC case) died (mean 6.7 months after surgery) because of their disease.</p><p><strong>Conclusion: </strong>Proximal SACs exhibit distinct clinicopathological and molecular features compared to distal SACs, largely aligning with the sessile serrated and traditional serrated pathways, respectively.</p>","PeriodicalId":11315,"journal":{"name":"Digestion","volume":" ","pages":"1-22"},"PeriodicalIF":3.6000,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Digestion","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1159/000548705","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GASTROENTEROLOGY & HEPATOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Introduction: Colorectal serrated adenocarcinoma (SAC), a subtype of colorectal adenocarcinoma determined histologically, has characteristics of epithelial serrations. Here, we examined the immunohistochemical and clinicopathological characteristics of colorectal SAC.
Methods: Thirty-three specimens, pathologically diagnosed as SAC in our hospital between 2013-2022, were collected for immunohistochemistry of MLH1/MUC2/MUC5AC/p53, and sequencing of BRAF/KRAS mutations.
Results: The proximal colon contained 25 lesions and the distal colon had 8. Patients with proximal SACs were predominantly female, whereas those exhibiting distal SACs were predominantly male (P = 0.003). Overall, lymph node and distant metastasis were present in 17 (52%) and 11 (33%) cases, respectively, with no significant differences between the proximal and distal groups. MLH1 expression loss was more frequent in proximal cases (40%) than distal SACs (13%). Most cases (97%) were MUC2+. MUC5AC+ was significantly more frequent in proximal cases (92%) than distal SACs (37%, P = 0.004). Significantly less p53 overexpression was present in proximal cases (40%) vs distal SACs (75%). Genetically, the 12 cases of SAC harboring BRAF mutations were all located in the proximal colon, with a significantly greater frequency (P = 0.030) whereas more frequent KRAS mutations were noted in distal SACs. Throughout 5 years of follow-up, three patients (two proximal SAC cases; one distal SAC case) died (mean 6.7 months after surgery) because of their disease.
Conclusion: Proximal SACs exhibit distinct clinicopathological and molecular features compared to distal SACs, largely aligning with the sessile serrated and traditional serrated pathways, respectively.
期刊介绍:
''Digestion'' concentrates on clinical research reports: in addition to editorials and reviews, the journal features sections on Stomach/Esophagus, Bowel, Neuro-Gastroenterology, Liver/Bile, Pancreas, Metabolism/Nutrition and Gastrointestinal Oncology. Papers cover physiology in humans, metabolic studies and clinical work on the etiology, diagnosis, and therapy of human diseases. It is thus especially cut out for gastroenterologists employed in hospitals and outpatient units. Moreover, the journal''s coverage of studies on the metabolism and effects of therapeutic drugs carries considerable value for clinicians and investigators beyond the immediate field of gastroenterology.