Darwish N, Guo L, Park E, Lee H. Acellular mucin in neoplastic and non-neoplastic conditions of the lower gastrointestinal tract. World J Gastrointest Surg 2025; 17(7): 106672 [DOI: 10.4240/wjgs.v17.i7.106672]
Corresponding Author of This Article
Hwajeong Lee, MD, Professor, Department of Pathology and Laboratory Medicine, Albany Medical Center, 43 New Scotland Ave, Albany, NY 12208, United States. leeh5@amc.edu
Research Domain of This Article
Pathology
Article-Type of This Article
Minireviews
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Gastrointest Surg. Jul 27, 2025; 17(7): 106672 Published online Jul 27, 2025. doi: 10.4240/wjgs.v17.i7.106672
Acellular mucin in neoplastic and non-neoplastic conditions of the lower gastrointestinal tract
Noureldien Darwish, Lynn Guo, Eundong Park, Hwajeong Lee
Noureldien Darwish, Lynn Guo, Eundong Park, Hwajeong Lee, Department of Pathology and Laboratory Medicine, Albany Medical Center, Albany, NY 12208, United States
Author contributions: Darwish N and Guo L wrote the original draft; Park E reviewed and edited the original draft; Lee H conceptualized the work, provided guidance, reviewed and edited the original draft; All authors read and approved the final version.
Conflict-of-interest statement: All authors declare no conflicts-of-interest related to this article.
Open Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Hwajeong Lee, MD, Professor, Department of Pathology and Laboratory Medicine, Albany Medical Center, 43 New Scotland Ave, Albany, NY 12208, United States. leeh5@amc.edu
Received: March 4, 2025 Revised: April 3, 2025 Accepted: May 22, 2025 Published online: July 27, 2025 Processing time: 141 Days and 17.1 Hours
Abstract
Acellular mucin refers to pools of mucin without epithelial component, oftentimes harboring inflammatory cells. Acellular mucin can be observed in both neoplastic and non-neoplastic lower gastrointestinal (GI) conditions. While mucinous neoplasms are classified and staged using established guidelines, interobserver variability occurs when acellular mucin pools are encountered, leading to inconsistent interpretation and staging. In particular, acellular mucin found in regional lymph nodes of colorectal adenocarcinoma patients who have not received treatment presents a diagnostic challenge, as its prognostic implication is not clearly defined. Acellular mucin is also commonly seen in treated colorectal adenocarcinoma, post neoadjuvant therapy. Although acellular mucin is not counted toward T or N staging in this setting, variation in how pathologists report and stage these cases persists. Acellular mucin can also be seen in non-neoplastic specimens, such as those from interval appendectomies, appendiceal diverticula, colonic diverticulitis, volvulus, and Crohn’s disease where it may mimic a neoplastic lesion. Acellular mucin in this setting is often a byproduct of inflammation, increased luminal pressure, and mural defect. This review highlights the clinical relevance and diagnostic complexity of acellular mucin in pathologic conditions of the lower GI tract. Further studies are needed to clarify its prognostic value and develop standardized guidelines.
Core Tip: Acellular mucin in both neoplastic and non-neoplastic lower gastrointestinal tract conditions may complicate diagnosis, prognostication and management. In colorectal and appendiceal mucinous neoplasms, it plays a role in tumor classification and staging. In non-neoplastic conditions, the presence of acellular mucin and related epithelial changes may mimic neoplasm and lead to additional work-up. This review highlights the diagnostic and prognostic implications of acellular mucin in neoplastic and non-neoplastic conditions, emphasizing the need for standardized approaches to improve pathological interpretation and management.
