At what size should a gallbladder (cholelithiasis) polyp warrant a cholecystectomy (surgical removal of the gallbladder)?

From the Guidelines

Cholecystectomy is recommended for gallbladder polyps that are 15 mm or larger in size, as the risk of malignancy significantly increases with polyp size, and early surgical intervention provides the best chance for cure if malignancy is present. The decision to perform a cholecystectomy for polyps between 10-14 mm should be made on a case-by-case basis, taking into account patient factors and evidence of growth on follow-up imaging 1. Polyps smaller than 10 mm can typically be monitored with regular ultrasound surveillance, as they rarely harbor malignancy. However, for patients with primary sclerosing cholangitis (PSC), cholecystectomy is recommended for polyps greater than or equal to 8 mm in size, or smaller polyps that are growing in size, due to the high risk of malignancy or dysplasia 1.

Key Considerations

• Polyp size is a significant predictor of malignancy, with larger polyps having a higher risk of being malignant or progressing to malignancy 1
• Patient factors, such as age over 50, concurrent gallstones, and primary sclerosing cholangitis, should be taken into account when deciding on cholecystectomy for polyps between 10-14 mm 1
• Regular ultrasound surveillance is recommended for polyps smaller than 10 mm, with follow-up intervals of 6-12 months 1
• Laparoscopic cholecystectomy is the standard approach, with conversion to open surgery sometimes necessary depending on intraoperative findings

Special Considerations for PSC Patients

• Cholecystectomy is recommended for polyps greater than or equal to 8 mm in size, or smaller polyps that are growing in size, due to the high risk of malignancy or dysplasia 1
• Careful risk-benefit assessment is required for PSC patients with liver decompensation, as they are at increased risk of complications after cholecystectomy 1

From the Research

Gallbladder Polyp Size and Cholecystectomy

• The size of a gallbladder polyp is a significant factor in determining whether a patient should undergo a cholecystectomy, with most studies suggesting that polyps larger than 10 mm should be considered for surgical removal 2, 3, 4.
• A study published in 2021 found that a polyp size larger than 12 mm may be a more reasonable threshold for surgical suggestion, with patients older than 43 years having a higher risk of having neoplastic polyps 5.
• Another study from 2005 recommended cholecystectomy for asymptomatic patients with gallbladder polyps greater than 1 cm in diameter, with the size of the polyp and the patient's age being important risk factors for malignant potential 6.
• The European Society of Gastrointestinal and Abdominal Radiology (ESGAR) and other organizations have published joint guidelines recommending cholecystectomy for patients with polypoid lesions of the gallbladder measuring 10 mm or more, and suggesting that patients with polyps between 6-9 mm and one or more risk factors for malignancy should also be considered for surgery 2, 4.

Risk Factors and Surveillance

• Risk factors for malignancy, such as age, primary sclerosing cholangitis, Asian ethnicity, and sessile polypoid lesions, should be taken into account when deciding whether to perform a cholecystectomy 2.
• Surveillance with ultrasound is recommended for patients with polyps between 6-9 mm and no risk factors for malignancy, with follow-up examinations at 6 months, 1 year, and 2 years 2.
• If a polyp grows to 10 mm or more during surveillance, cholecystectomy is advised, and if a polyp grows by 2 mm or more within the 2-year follow-up period, the current size of the polyp and patient risk factors should be considered in deciding whether to continue monitoring or perform surgery 2.