Gallbladder polyps are common findings in abdominal ultrasound exams, appearing in about 4.5% of adults. While most of them do not have malignant potential, a small percentage – between 4% and 10% – are adenomas, which can become malignant.
Studies show that the size of the polyp is the main risk factor for the development of cancer, especially when adenomatous polyps are 10 millimeters or more, presenting a chance of malignancy between 37% and 55%.
However, it is difficult to differentiate between adenomatous polyps and polyps without malignant potential in preoperative exams. Therefore, it is important for the gastroenterologist to know the correct indication for surgery in patients with gallbladder polyps in order to avoid an unnecessary surgical procedure in patients without risk and, mainly, correctly indicating the procedure in the population with a higher risk of malignancy.
In this article, we will summarize the indications for follow-up and treatment of gallbladder polyps.
SYMPTOMATIC PATIENTS
Gallbladder polyps rarely cause symptoms, however some studies have reported an association between gallbladder polyps and undetected stones on ultrasound and/or cholecystitis. The joint European guideline of 2022 recommends cholecystectomy for patients who present symptoms such as biliary colic or complications (example: pancreatitis) and who have favorable clinical conditions for surgery [1]. The rate of symptom improvement is variable in the literature (40-90% improvement).
Patients with nonspecific dyspeptic symptoms without biliary colic should be treated conservatively (unless there are other indications for polyp removal), since the pathogenesis of these symptoms is not clear and cholecystectomy may not relieve symptoms. These patients should be treated symptomatically, as with other patients with functional dyspepsia.
ASYMPTOMATIC PATIENTS WITH RISK FACTORS FOR GALLBLADDER CANCER
Risk factors for gallbladder cancer include:
- age >60 years
- primary sclerosing cholangitis
- Asian ethnicity
- sessile polyps with focal gallbladder wall thickness >4 mm
The approach will depend on the size of the polyp:
- Polyps ≤5 mm: surveillance ultrasound at 6 months, 1 year, and 2 years. Follow-up can be discontinued if there is no growth during this period.
- Polyps 6 to 9 mm: cholecystectomy is recommended if the patient is clinically fit and accepts surgery.
- Polyps 10 to 20 mm: Polyps 10 to 20 mm should be considered as possibly malignant. Laparoscopic cholecystectomy is recommended.
- Polyps >20 mm: are generally malignant. Patients should undergo preoperative staging with computed tomography or endoscopic ultrasound. Radical treatment consists of extended cholecystectomy with lymph node dissection and partial hepatic resection at the gallbladder bed.
ASYMPTOMATIC PATIENTS WITHOUT RISK FACTORS FOR GALLBLADDER CANCER
In asymptomatic patients without risk factors for gallbladder cancer, surveillance recommendations vary according to the size of the polyp.
- For polyps ≤ 5 mm: no follow-up is necessary. *
- For polyps 6 to 9 mm: perform abdominal ultrasound at 6 months, 1 year, and 2 years. Surveillance can be discontinued if there is no growth during this period.
* This strategy is aligned with the practices of the American College of Radiology [2] and the Canadian Association of Radiologists Incidental Findings Working Group [3], which recommend that polyps smaller than 7 mm do not require follow-up.
IMPORTANT CONSIDERATIONS IN PATIENTS UNDERGOING SURVEILLANCE
1. Increase in polyp size
The joint European guideline of 2017 recommended that:
- An increase in size greater than 2 mm in the images probably represents a clinically significant increase and should prompt referral to a surgeon for cholecystectomy.
The update of this guideline in 2022 recommends that:
- If the polypoid lesion grows 2 mm or more during the 2-year follow-up period, then the current size of the polypoid lesion should be considered along with the patient’s risk factors. Multidisciplinary discussion should be held to decide whether to continue surveillance or if cholecystectomy is indicated.
An important retrospective study published in 2019 including more than 600,000 adults undergoing cholecystectomy showed that:
- The growth of 2 mm or more seems to be part of the natural history of gallbladder polyps.
- The likelihood of a polyp growing at least 2 mm in 10 years was 66% for polyps smaller than 6 mm and 53% for polyps between 6-10mm.
- Important: this growth does not seem to be associated with future gallbladder cancer. None of the 507 patients with polyps that grew to 10 mm or more were subsequently diagnosed with cancer.
- The first year is the most important:
- Most cases of gallbladder cancer were diagnosed in the first year, probably representing neoplasms already present at the time of diagnosis.
- Polyps initially smaller than 10 mm were almost never associated with future cases of gallbladder cancer (rate 1.05 per 100,000 person-years)
- Polyps with ≥ 10 mm at diagnosis were rarely associated with gallbladder cancer after the first year.
The cherry on top of this study:
- In addition, we observed that similar proportions of adults were diagnosed with gallbladder Ca (0.053% vs. 0.054%), whether an initial ultrasound showed a gallbladder polyp or not. These findings suggest that there may not be a general link between gallbladder polyps and gallbladder neoplasia, and that gallbladder polyps are an incidental finding.
2. Duration of surveillance
The duration of surveillance in patients with gallbladder cancer is not clear. The updated joint European guidelines recommend discontinuing surveillance in two years if there is no growth of the polyps. Some authors recommend maintaining surveillance for at least five years. However, in patients with risk factors for gallbladder cancer, we should maintain surveillance for gallbladder cancer with abdominal USG indefinitely.
3. Adenomyomatosis
Patients with typical features of adenomyomatosis on ultrasound do not require surveillance or cholecystectomy.
4. If the gallbladder polyp disappears during follow-up
If the gallbladder polyp disappears during follow-up, the follow-up surveillance can be discontinued.
References
- Foley KG, Lahaye MJ, Thoeni RF, Soltes M, Dewhurst C, Barbu ST, Vashist YK, Rafaelsen SR, Arvanitakis M, Perinel J, Wiles R, Roberts SA. Management and follow-up of gallbladder polyps: updated joint guidelines between the ESGAR, EAES, EFISDS and ESGE. Eur Radiol. 2022 May;32(5):3358-3368. doi: 10.1007/s00330-021-08384-w. Epub 2021 Dec 17. PMID: 34918177; PMCID: PMC9038818.
- Sebastian S, Araujo C, Neitlich JD, Berland LL (2013) Manag- ing incidental findings on abdominal and pelvic CT and MRI, Part 4: white paper of the ACR Incidental Findings Commit- tee II on gallbladder and biliary findings. J Am Coll Radiol 10(12):953–956
- Bird JR, Brahm GL, Fung C, Sebastian S, Kirkpatrick IDC (2020) Recommendations for the management of incidental hepatobiliary findings in adults: endorsement and adaptation of the 2017 and 2013 ACR Incidental Findings Committee White Papers by the Canadian Association of Radiologists Incidental Findings Working Group. Can Assoc Radiol J 71(4):437–447
- Szpakowski JL, Tucker LY. Outcomes of Gallbladder Polyps and Their Association With Gallbladder Cancer in a 20-Year Cohort. JAMA Netw Open. 2020 May 1;3(5):e205143. doi: 10.1001/jamanetworkopen.2020.5143. PMID: 32421183; PMCID: PMC7235691.
How to cite this article
Martins BC. Management of Gallbladder Polyps: When to Follow Up and When to Recommend Cholecystectomy? Gastropedia 2024; vol 1. Available at: https://gastropedia.pub/en/surgery/management-of-gallbladder-polyps-when-to-follow-up-and-when-to-recommend-cholecystectomy
Professor Livre-Docente pela Faculdade de Medicina da Universidade de São Paulo
Médico Endoscopista do Instituto do Câncer do Estado de São Paulo (ICESP)
Médico Endoscopista do Hospital Alemão Oswaldo Cruz
Emerging Star pela WEO
