--- title: Korean radiologists raised the gallbladder polyp surgery threshold to 15 mm. Now they are defending it in print publication: Medical Insights Korea section: news category: Gallbladder canonical_url: https://medicalinsightskorea.com/news/ksar-gallbladder-polyp-threshold-challenged author: Catherine Cho published: 2026-09-01T08:40:00+09:00 modified: 2026-09-01T08:40:00+09:00 content_type: reporting license: Quotation permitted with attribution to Medical Insights Korea and a link to the canonical URL. --- # Korean radiologists raised the gallbladder polyp surgery threshold to 15 mm. Now they are defending it in print A commentary from Peking Union Medical College Hospital says the new 10–14 mm category needs prospective validation. The guideline's authors agree it does — and published the recommendation anyway. ## Answer The Korean Society of Abdominal Radiology raised the threshold for firmly recommending gallbladder polyp surgery from 10 mm to 15 mm in January 2025; radiologists at Peking Union Medical College Hospital challenged the change in print, arguing the new 10–14 mm category needs prospective validation before optional surgery can be called safe. ## Key takeaways - The Korean Society of Abdominal Radiology's January 2025 recommendations subdivide gallbladder polyps of 10 mm or more into 10–14 mm and 15 mm or larger, recommending cholecystectomy firmly only for the larger group. - Chen Lin and Liang Zhu of Peking Union Medical College Hospital published a commentary in May 2025 arguing that prospective studies of malignancy rates in the 10–14 mm category are needed before optional cholecystectomy can be called safe. - Jeong Hee Yoon of Seoul National University Hospital replied for the guideline authors, citing the modest performance of the 10 mm cutoff in the published literature as the basis for the change. - The guideline authors conceded that supporting data were too limited to weight their three concerning imaging features differently, and weighted them equally to keep the decision simple. - The European joint guideline in force since 2022 continues to recommend cholecystectomy at 10 mm. ## Full article Guidelines usually change quietly. This one did not. Eight weeks after the Korean Society of Abdominal Radiology published recommendations that moved the size at which a gallbladder polyp is firmly referred for surgery from 10 mm to 15 mm, two clinicians in Beijing published a commentary in the same journal saying the evidence was not yet there. The guideline's authors replied in the following issue. The exchange is unusually direct for a specialty that ordinarily settles disagreements over several years and a great many citations, and it turns on a question that reaches every patient who has ever been told an incidental finding needs watching: how large does a polyp have to be before the risk of leaving it outweighs the risk of an operation. ### What the Korean recommendations changed The 10 mm threshold has been the working rule internationally for decades, and the European joint guideline issued in 2022 by the European Society of Gastrointestinal and Abdominal Radiology and three partner societies still applies it: a polypoid lesion of 10 mm or more is referred for cholecystectomy in a patient fit for surgery. The Korean document, published in the Korean Journal of Radiology in January 2025, splits that group in two. Polyps of 15 mm or more are recommended for cholecystectomy rather than continued ultrasound. Polyps of 10 to 14 mm are referred for surgery only where a concerning imaging feature is present; without one, surgery is described as optional and continued surveillance is acceptable. **The 10 mm and over group, before and after** | Polyp size | European joint guideline (2022) | Korean recommendations (2025) | | --- | --- | --- | | 10–14 mm | Cholecystectomy | Cholecystectomy if a concerning feature is present; otherwise optional, with follow-up acceptable | | 15 mm or more | Cholecystectomy | Cholecystectomy | Three features count as concerning: adjacent gallbladder wall thickening, sessile morphology, and significant growth between scans. ### The challenge from Beijing In the May 2025 issue, Chen Lin of the Department of General Surgery and Liang Zhu of the Department of Radiology, both at Peking Union Medical College Hospital, set out three objections. None of them disputes the direction of travel. All of them concern whether the evidence has caught up with it. On the new 10 to 14 mm category, they accepted that emerging data show lower neoplastic risk below 15 mm, but wrote that validation studies are still required to assess long-term outcomes against the traditional threshold. > Prospective studies examining malignancy rates in the 10–14 mm category would assist in confirming the safety of optional cholecystectomy in this cohort. > > — Chen Lin and Liang Zhu, Peking Union Medical College Hospital, Korean Journal of Radiology, May 2025 Their second objection was that the three concerning features are treated as interchangeable when they are unlikely to carry equal weight, and that the relative contribution of each to malignancy risk remains unclear. Their third was that the follow-up schedule itself needs testing in practice — adherence, cost-effectiveness, and outcomes across different health systems. ### The reply from Seoul Jeong Hee Yoon of Seoul National University Hospital answered for the guideline authors in the same issue. The defence rested less on new evidence than on the weakness of the thing being replaced: the 10 mm cutoff, the reply argued, performs modestly in the published literature, and risk continues to vary above it rather than jumping at it. The Korean subcategorisation, Yoon noted, aligns with the most recent recommendation from the Society of Radiologists in Ultrasound. That argument has independent support. A systematic review and meta-analysis published in the British Journal of Radiology in 2022 pooled 82 studies covering 67,837 patients and found the cumulative risk of gallbladder cancer at a polyp size of 10 mm to be 0.60 percent. **0.60%** — median cumulative gallbladder cancer risk at a polyp size of 10 mm (99% credible range 0.30–1.16%) _Source: Foley KG et al., British Journal of Radiology, 2022_ Those authors concluded that a step increase in risk above 10 mm was neither likely nor supported by their data — the empirical case the Korean document is built on. ### What the authors conceded The reply is notable for what it does not contest. On the weighting of imaging features, Yoon agreed the question warrants further investigation, and explained the equal weighting as a deliberate simplification made because the supporting data were limited — a choice for usability over precision, stated as such. - Data supporting differential weighting of the three concerning features were described as limited. - Further research quantifying their individual and combined predictive value was described as needed. - A systematic evaluation of the follow-up schedule across diverse healthcare settings was described as beneficial. The disagreement, in other words, is not really about the facts. Both sides accept that the evidence for the new categories is incomplete. They differ on what a guideline is for: whether it should wait for validation, or codify the best available reading of the evidence and be corrected later. > **What this means for patients in Korea** > A patient with a 10 to 14 mm polyp and no concerning imaging feature may now be offered surveillance in Korea where European guidance would have advised surgery. Asking which document the recommendation follows, and whether any concerning feature is present, is the fastest way to know which of the two is being applied. ## Sources - Chang W, Lee S, Kim Y-Y, et al. Interpretation, Reporting, Imaging-Based Workups, and Surveillance of Incidentally Detected Gallbladder Polyps and Gallbladder Wall Thickening: 2025 Recommendations From the Korean Society of Abdominal Radiology. Korean Journal of Radiology 2025;26(2):102-134. doi:10.3348/kjr.2024.0914. PMID:39898393. https://doi.org/10.3348/kjr.2024.0914 - Lin C, Zhu L. 2025 Korean Society of Abdominal Radiology Recommendations on Gallbladder Polyps and Gallbladder Wall Thickening Warrant Further Investigation and Clarification. Korean Journal of Radiology 2025;26(5):514-515. doi:10.3348/kjr.2025.0201. PMID:40169502. https://pmc.ncbi.nlm.nih.gov/articles/PMC12055273/ - Yoon JH. Response to "2025 Korean Society of Abdominal Radiology Recommendations on Gallbladder Polyps and Gallbladder Wall Thickening Warrant Further Investigation and Clarification". Korean Journal of Radiology 2025;26(5):516-517. doi:10.3348/kjr.2025.0216. PMID:40169499. https://pmc.ncbi.nlm.nih.gov/articles/PMC12055274/ - Foley KG, Lahaye MJ, Thoeni RF, et al. Management and follow-up of gallbladder polyps: updated joint guidelines between the ESGAR, EAES, EFISDS and ESGE. European Radiology 2022;32(5):3358-3368. doi:10.1007/s00330-021-08384-w. PMID:34918177. https://pmc.ncbi.nlm.nih.gov/articles/PMC9038818/ - Foley KG, Riddell Z, Coles B, Roberts SA, Willis BH. Risk of developing gallbladder cancer in patients with gallbladder polyps detected on transabdominal ultrasound: a systematic review and meta-analysis. British Journal of Radiology 2022;95(1137):20220152. doi:10.1259/bjr.20220152. PMID:35819918. https://pmc.ncbi.nlm.nih.gov/articles/PMC10996949/ ## Citation Catherine Cho (2026). "Korean radiologists raised the gallbladder polyp surgery threshold to 15 mm. Now they are defending it in print". Medical Insights Korea. https://medicalinsightskorea.com/news/ksar-gallbladder-polyp-threshold-challenged Retrieved from https://medicalinsightskorea.com/news/ksar-gallbladder-polyp-threshold-challenged