Polyps are abnormal tissue growths. They can form in various parts of the body, including the gallbladder.
Though some gallbladder polyps can develop into cancer, the vast majority are noncancerous.
As long as the polyps are smaller than 1 centimeter (cm) and cause no symptoms, treatment is unnecessary.
Keep reading to learn more about the symptoms and potential complications of gallbladder polyps. We also describe the association between gallbladder polyps and cancer, as well as the treatments.
A polyp is an abnormal growth of tissue. Some polyps are small, flat bumps, while others are suspended from tiny stalks.
Polyps can form in various parts of the body, including the gallbladder. Researchers estimate that gallbladder polyps affect between 0.3% and 9.5% of the population.
There are three main types of gallbladder polyp: pseudopolyps, inflammatory polyps, and true gallbladder polyps.
Doctors usually find inflammatory polyps in people who have experienced cholecystitis more than once or people who have acute biliary colic, which involves a gallstone blocking the duct of the gallbladder. It typically results in pain after eating.
Inflammatory polyps, like pseudopolyps, are not associated with gallbladder cancer.
True gallbladder polyps
True gallbladder polyps are rare and have the potential to become cancerous.
When a person has larger polyps, the doctor may recommend removing the gallbladder.
Gallbladder polyps do not always cause symptoms. In many cases, doctors discover them incidentally, on ultrasound or CT scans.
However, gallbladder polyps can cause the following symptoms:
People with high levels of cholesterol or salts in their bile have an increased risk of developing gallbladder polyps. Bile is produced by the liver and stored in the gallbladder. Its main function is to help the body digest fat.
Gallbladder polyps are also associated with the formation of gallstones. Many people have both gallbladder polyps and gallstones.
Also, as a 2019 review notes, the following health issues may increase a person's risk of developing true gallbladder polyps:
- familial polyposis, an inherited condition
- Gardner syndrome, a type of familial polyposis
- Peutz-Jeghers syndrome, a genetic condition
- hepatitis B, an infection that can be acute or chronic
The majority of gallbladder polyps are pseudopolyps or inflammatory polyps. These do not cause complications and are not associated with cancer.
However, doctors regularly monitor all gallbladder polyps, regardless of their type. Removal of the gallbladder is only necessary if people experience symptoms or if a polyp grows larger than 1 cm.
The most significant complication of true gallbladder polyps is gallbladder cancer.
Only true gallbladder polyps are associated with cancer. The stages of gallbladder cancer range from 0–5, with stage 5 being the most advanced.
The 5-year survival rate for stage 1 gallbladder cancer is less than 50%.
Doctors detect fewer than 10% of gallbladder cancer cases when they are stages 0 or 1. They diagnose the majority of cancerous gallbladder polyps when they are more advanced than stage 1.
Below are factors that can increase the risk of developing gallbladder cancer:
- being over 50 years of age
- being of Indian ethnicity
- having a history of primary sclerosing cholangitis
- having a flat, or sessile, polyp, along with thickening of the gallbladder wall.
Meanwhile, research indicates that people with pseudopolyps or inflammatory gallbladder polyps have almost no risk of developing gallbladder cancer.
Nonetheless, doctors monitor all gallbladder polyps closely. Those that grow larger than 1 cm have a higher likelihood of becoming cancerous. When a person has a polyp of this size, the doctor will advise removal of the gallbladder.
Pseudopolyps and inflammatory polyps that are smaller than 1 cm and do not cause symptoms do not require treatment.
However, doctors routinely monitor all gallbladder polyps, using ultrasound scans. The first scan usually takes place 6 months after the initial discovery of the polyp. Subsequent scans tend to occur at yearly intervals.
If a polyp has grown by 2 mm or more since the last checkup, the doctor will recommend treatment.
Treatment is surgical removal of the gallbladder. This is called cholecystectomy. There are two types:
Open cholecystectomy (OC): This involves the surgeon removing the gallbladder via a large incision under the right side of the ribcage.
Laparoscopic cholecystectomy (LC): This involves the surgeon removing the gallbladder via small incisions in the abdomen.
According to researchers, lower mortality rates are associated with LC, compared with OC.
However, some significant complications are more likely to result from LC. They include:
- bile duct injuries
- internal or external bleeding
- abscesses under the liver
Currently, the only treatment for gallbladder polyps is surgical removal of the gallbladder.
People with high cholesterol may have an increased risk of developing cholesterol polyps. Lowering cholesterol levels in the blood may help prevent cholesterol polyps from forming.
The American College of Cardiology (ACA) and similar institutions recommend dietary changes for people with high cholesterol.
A low cholesterol diet includes plenty of the following foods:
- whole grains
- low fat dairy
- low fat poultry
- nontropical vegetable oils
People with high cholesterol should also limit their intake of:
- sugar-sweetened beverages
- red meats
The ACA also recommend that people with high cholesterol get aerobic exercise 3–4 times per week. Each 40-minute session should involve moderate or vigorous exercise.
Also, some people need to take medication that lowers their cholesterol.
People with gallbladder polyps may not experience symptoms.
Most gallbladder polyps are noncancerous, but they still require regular monitoring.
Surgery is necessary if polyps cause symptoms or are larger than 1 cm. Doctors also recommend surgery when a polyp has grown by 2 mm or more since the last checkup.
True gallbladder polyps are rare, and they can cause gallbladder cancer. The treatment involves surgical removal of the gallbladder. Survival rates for people with this type of cancer are higher when doctors detect the cancer and intervene early.