From the Guidelines
The recommended management for gallbladder polyps depends primarily on their size and risk factors, with polyps smaller than 10mm generally warranting surveillance with ultrasound every 6-12 months, while those 10mm or larger typically requiring surgical removal via cholecystectomy due to their higher risk of malignancy.
Key Considerations
- For polyps between 6-9mm, closer monitoring is advised, especially in patients over 50 years old or with risk factors such as primary sclerosing cholangitis or a history of colorectal cancer, as suggested by 1 and 1.
- Surveillance can be discontinued after 3-5 years if polyps remain stable.
- Symptomatic polyps causing biliary colic or cholecystitis should be surgically removed regardless of size.
- Laparoscopic cholecystectomy is the preferred surgical approach, with conversion to open surgery if needed, as discussed in 1.
Risk Stratification
- The Society of Radiologists in Ultrasound consensus conference guidelines provide evidence-based and expert consensus–based risk-stratified management recommendations for incidentally detected gallbladder polyps at US, as outlined in 1 and 1.
- Gallbladder polyps are stratified into three categories: extremely low risk, low risk, and indeterminate risk, based on their morphologic features.
- Extremely low risk polyps are pedunculated with a “ball-on-the-wall” configuration or thin stalk; low risk polyps are pedunculated with a thick or wide stalk or sessile configuration; indeterminate risk polyps have focal wall thickening adjacent to the polyp.
Growth and Malignancy Risk
- Rapid sustained growth is conceptually concerning, although specific criteria for an objective size increase and time interval that constitute concerning growth are not well established, as noted in 1.
- The SRU consensus conference committee agreed that growth of up to 3 mm may be part of the natural history of nonmalignant gallbladder polyps, and that growth of 4 mm or more within 1 year constitutes rapid growth.
- Patients with primary sclerosing cholangitis (PSC) are at an increased risk of gallbladder carcinoma, and cholecystectomy is recommended in people with PSC with gallbladder polyps greater or equal to 8 mm in size and smaller polyps growing in size, due to the high risk of malignancy or dysplasia, as recommended by 1.
From the Research
Recommended Management for Gallbladder Polyps
The management of gallbladder polyps is a complex issue, and several studies have investigated the best approach. According to the guidelines updated by the European Society of Gastrointestinal and Abdominal Radiology (ESGAR), European Association for Endoscopic Surgery and other Interventional Techniques (EAES), International Society of Digestive Surgery-European Federation (EFISDS), and European Society of Gastrointestinal Endoscopy (ESGE) 2, the following recommendations can be made:
- Primary investigation of polypoid lesions of the gallbladder should be with abdominal ultrasound.
- Cholecystectomy is recommended in patients with polypoid lesions of the gallbladder measuring 10 mm or more.
- Cholecystectomy is suggested for patients with a polypoid lesion and symptoms potentially attributable to the gallbladder if no alternative cause for the patient's symptoms is demonstrated.
- If the patient has a 6-9 mm polypoid lesion of the gallbladder and one or more risk factors for malignancy, cholecystectomy is recommended.
Risk Factors for Malignancy
Several risk factors for malignancy have been identified, including:
- Age more than 60 years
- History of primary sclerosing cholangitis (PSC)
- Asian ethnicity
- Sessile polypoid lesion (including focal gallbladder wall thickening > 4 mm)
Follow-up and Surveillance
For patients with gallbladder polyps, follow-up and surveillance are crucial. According to the guidelines 2, follow-up ultrasound of the gallbladder is recommended at 6 months, 1 year, and 2 years for patients with:
- A 6-9 mm polypoid lesion and no risk factors for malignancy
- A polypoid lesion of 5 mm or less and risk factors for malignancy
- If the patient has no risk factors for malignancy and a gallbladder polypoid lesion of 5 mm or less, follow-up is not required.
Diagnostic Accuracy of Imaging Modalities
Several studies have investigated the diagnostic accuracy of imaging modalities, including transabdominal ultrasound (TAUS) and endoscopic ultrasound (EUS) 3. The results show that:
- TAUS has a high sensitivity and specificity for detecting gallbladder polyps
- EUS has a higher sensitivity and specificity for differentiating between true and pseudo polyps, and between dysplastic polyps/carcinomas and adenomas/pseudo polyps
Management of Neoplastic Gallbladder Polyps
Neoplastic gallbladder polyps (NGP) are rare and associated with a risk of malignant degeneration 4. The management of NGP includes:
- Abdominal sonography as the first line study for diagnosis and follow-up
- Cholecystectomy for NGP larger than 10mm, or symptomatic, or larger than 6mm with associated risk factors for cancer
- Simple sonographic surveillance for at least five years for NGP that do not meet the criteria for cholecystectomy.