The gallbladder is a small organ located beneath the liver that stores and concentrates bile, which aids in fat digestion. A gallbladder polyp is a growth or lesion projecting from the organ’s inner lining. These growths are common, often discovered incidentally during imaging tests, leading many newly diagnosed individuals to question if they cause pain.
What Exactly Are Gallbladder Polyps?
Gallbladder polyps are broadly categorized into two major groups: non-neoplastic, which are overwhelmingly benign, and neoplastic, which have the potential to become malignant. The vast majority, up to 90%, are non-neoplastic and are often referred to as pseudopolyps. The most common type is the cholesterol polyp, which is a deposit of cholesterol lipids that accumulate on the gallbladder wall, a condition known as cholesterolosis.
Cholesterol polyps are non-cancerous and typically small, often less than 5 millimeters in diameter. Other non-neoplastic types include inflammatory polyps, which are essentially scar tissue resulting from chronic inflammation, and adenomyomatosis, an abnormal thickening of the gallbladder lining. In contrast, neoplastic polyps, such as adenomas, are much rarer true tumors composed of abnormal cells that carry a risk of transforming into cancer.
Connecting Polyps to Pain and Other Symptoms
The majority of gallbladder polyps are asymptomatic, meaning they do not cause noticeable symptoms, including pain. They are frequently discovered incidentally during an abdominal ultrasound. When pain occurs, it is often due to a complication or an associated condition, not the polyp itself.
Pain in the upper right abdomen may be related to the polyp if it is large enough to obstruct a duct leading from the gallbladder, such as the cystic duct. This obstruction can lead to inflammation of the gallbladder wall, a painful condition called cholecystitis. A polyp can also act as a surface for gallstone formation; the movement or lodging of a gallstone is a much more common cause of severe, cramping pain known as biliary colic.
In some instances, the gallbladder’s contraction after eating a fatty meal may cause discomfort if a larger polyp is compressed against the wall. Symptoms rarely associated with polyps include nausea, vomiting, or vague discomfort in the right upper quadrant. However, for a small, non-neoplastic polyp, any accompanying pain is likely attributable to an entirely separate issue.
Assessing the Risk: When Should Polyps Cause Concern?
The primary concern is the risk that a gallbladder polyp could be or become malignant. This risk is highly dependent on the polyp’s characteristics. Size is the most significant indicator for cancer potential, with 10 millimeters (mm) acting as the key threshold.
Polyps 10 mm or larger have a significantly increased likelihood of malignancy, prompting guidelines to recommend surgical removal of the gallbladder (cholecystectomy). Polyps smaller than 10 mm are far less likely to be cancerous. The growth rate is another factor, as an increase in size of 2 mm or more within a two-year period is a concerning sign, regardless of the initial size.
Patient-specific factors also modify the risk profile. These include being over the age of 60, having the co-occurring condition primary sclerosing cholangitis, or belonging to an Asian ethnic group. Additionally, polyps that have a broad base attached to the wall, known as sessile polyps, are viewed with greater caution than those attached by a narrow stalk.
Diagnosis and Medical Management Options
Abdominal ultrasound is the first line of diagnosis for a gallbladder polyp. It is highly effective due to its accessibility and ability to clearly visualize the gallbladder lining. This imaging technique allows clinicians to measure the polyp’s size and note its characteristics, such as whether it is pedunculated or sessile. Other imaging modalities like CT or MRI may be used in more complex cases to better differentiate between benign and malignant lesions.
For small, low-risk polyps—typically those 5 mm or less in size without any associated risk factors—no follow-up is generally required. For polyps between 6 and 9 mm, or for smaller polyps in patients with risk factors, the standard approach is “wait and watch.” This involves serial ultrasound monitoring over a period of time, such as every 6 to 12 months. This surveillance aims to detect any concerning growth or changes early.
Surgical removal of the gallbladder, or cholecystectomy, is the definitive treatment. It is strongly recommended for polyps that reach or exceed the 10 mm size threshold. Surgery is also advised for any polyp size if it is suspected of causing symptoms, especially if alternative causes have been ruled out. If a polyp shows rapid growth, defined as 2 mm or more within two years, or if there is a combination of risk factors, cholecystectomy is typically considered to prevent the potential development of gallbladder cancer.