May 2025

Risk stratification model for incidentally detected gallbladder polyps:
A multicentre study

Congyu Tang, Zhidan Geng, Jiexian Wen, Lifan Wang, Qiqin You, Yunjie Jin, Wenping Wang, Huixiong Xu, Qing Yu, Haixia Yuan

European Journal of Radiology 170 (2024) 111244

DOI: 10.1016/j.ejrad.2023.111244

The increasing prevalence of incidentally detected gallbladder polyps through routine ultrasound examinations has highlighted the need for improved risk stratification strategies. These lesions, although often benign, can include neoplastic entities such as adenomas and gallbladder carcinomas, which carry malignant potential. The clinical challenge lies in accurately distinguishing polyps that require intervention from those that can be safely monitored. Current management paradigms, primarily reliant on a 10 mm size threshold, are limited by suboptimal sensitivity and specificity, leading to both overtreatment and missed malignancies [1].

In this multicentre study, Congyu Tang et al. propose a newly developed four-tier ultrasound-based risk stratification model, designed to enhance diagnostic precision and support individualized clinical decision-making. The research involved three academic centers and included 370 patients with histopathologically confirmed gallbladder polyps. A retrospective training cohort (n = 264) was used to identify independent ultrasound predictors of neoplastic and malignant lesions through logistic regression analysis. A separate prospective validation cohort (n = 106) was subsequently analyzed to assess the generalizability and performance of the scoring system [2].

Crucially, the authors selected only ultrasound features demonstrating excellent interobserver agreement (ICC ≥ 0.75), enhancing the reliability of the model across different operators. This methodological decision adds practical value to the proposed algorithm, making it suitable for broad clinical implementation [3].
 

The following table summarizes the individual scoring values assigned to each ultrasound feature:

Based on the cumulative score, gallbladder polyps were stratified into four distinct risk categories:

• Extremely low-risk (≤6 mm): 0% malignancy
• Low-risk (1–8 points): 1.28% malignancy
• Intermediate-risk (9–14 points): 9.26% malignancy
• High-risk (≥15 points): 70.37% malignancy

The model demonstrated excellent discriminatory performance. In the validation cohort, the area under the receiver operating characteristic curve (AUC) reached 0.925 for neoplastic polyps and 0.949 for malignant polyps, emphasizing the model’s strong predictive performance across datasets [4].

Importantly, this risk stratification model facilitates more informed and standardized clinical pathways. It allows clinicians to triage patients based on their malignancy risk, offering clear follow-up or treatment recommendations:

• Extremely low-risk polyps: annual surveillance
• Low-risk polyps: follow-up at 6 months
• Intermediate-risk polyps: short-term imaging re-evaluation and consideration of elective    cholecystectomy
• High-risk polyps: recommendation for early surgical resection
  
   

One of the key strengths of this model lies in its exclusive reliance on conventional ultrasound — a widely available, cost-effective, and non-invasive imaging modality. By leveraging routinely acquired sonographic features with high interobserver agreement, the scoring system can be seamlessly applied in a variety of clinical environments, from tertiary hospitals to community-based practices. This practicality enhances its potential for immediate clinical adoption and broader impact across healthcare systems with varying levels of imaging infrastructure [5].

This work is of particular interest to ESGAR members as it addresses a longstanding clinical dilemma using a reproducible, evidence-based approach grounded in conventional ultrasound imaging. It advances the field toward a more refined, structured framework for evaluating and managing gallbladder polyps in daily radiological practice.

References

1. Aya Kamaya, Christopher Fung, Jean-Luc Szpakowski, et al. (2022) Management of incidentally detected gallbladder polyps: Society of Radiologists in Ultrasound consensus conference recommendations. Radiology 305:277–289. doi: https://doi.org/10.1148/radiol.213079

2. Zhu Lianhua, Han Peng, Jiang Bo, et al. (2021) Value of conventional ultrasound-based scoring system in distinguishing adenomatous polyps from cholesterol polyps. Journal of Clinical Gastroenterology56(10):895–901. doi: https://doi.org/10.1097/MCG.0000000000001639

3. Kieran G. Foley, Max J. Lahaye, Ruedi F. Thoeni, et al. (2022) Management and follow-up of gallbladder polyps: updated joint guidelines between the ESGAR, EAES, EFISDS and ESGE. European Radiology 32(5):3358–3368. doi: https://doi.org/10.1007/s00330-021-08384-w

4. Qi Li, Minghui Dou, Hengchao Liu, et al. (2024) Prediction of neoplastic gallbladder polyps in patients with different age levels based on preoperative ultrasound: a multi-center retrospective real-world study. BMC Gastroenterology 24:64. doi: https://doi.org/10.1186/s12876-024-03240-9

5. Xue-Song Liu, Tao Chen, Li-Hong Gu, et al. (2018) Ultrasound-based scoring system for differential diagnosis of polypoid lesions of the gallbladder. Journal of Gastroenterology and Hepatology 33(6):1295–1299. doi: https://doi.org/10.1111/jgh.14080

Evangelos Tsangouris is a second-year Radiology Resident at Konstantopouleio General Hospital in Nea Ionia, Athens, Greece. He completed his undergraduate Μedical degree at the National and Kapodistrian University of Athens. He has a wide range of interests in diagnostic imaging, especially regarding the hepatobiliary system.

Comments may be sent to vaggelis071998@gmail.com