Gallbladder polyps refer to morphological lesions that project or elevate into the lumen of the gallbladder. These lesions are spherical, hemispherical, or papillary in shape, may be pedunculated or sessile, and are generally benign. Pathologically, gallbladder polyps can be classified into the following categories:
Neoplastic Polyps
This category includes adenomas and adenocarcinomas, as well as rarer types such as hemangiomas, lipomas, leiomyomas, and neurofibromas.
Non-neoplastic Polyps
This category encompasses cholesterol polyps, inflammatory polyps, and adenomyomatous hyperplasia. Rare variants include adenomatous hyperplasia, xanthogranulomas, and ectopic tissues such as gastric mucosa or pancreatic tissue. Given the difficulty in determining the nature of polyps before surgery, such lesions are collectively referred to as "polypoid lesions of the gallbladder" or "elevated lesions of the gallbladder."
Cholesterol polyps result from the deposition of cholesterol crystals on the gallbladder mucosa. Inflammatory polyps are associated with mucosal proliferation, are often multiple, and typically measure less than 1 cm in diameter. They frequently coexist with gallstones and cholecystitis. Adenomyomatous hyperplasia is a benign proliferative lesion of the gallbladder wall, and when localized, it may resemble a tumor.
Gallbladder polyps are generally asymptomatic and are often discovered incidentally during ultrasonographic examinations as part of routine health checkups. A small number of patients may experience symptoms such as right upper abdominal pain, nausea, vomiting, and loss of appetite. Rare cases may present with obstructive jaundice, acalculous cholecystitis, biliary bleeding, or pancreatitis. On physical examination, there may be tenderness in the right upper abdomen.
Clinical diagnosis often requires the use of the following investigations:
- Routine ultrasound.
- Endoscopic ultrasound (EUS).
- CT or MRI.
- Ultrasound-guided percutaneous fine-needle aspiration biopsy.
Although rare, some gallbladder polyps may undergo malignant transformation, and some may represent early-stage gallbladder cancer. This possibility warrants clinical attention. Risk factors for malignant transformation of gallbladder polyps include:
- Polyps larger than 1 cm in diameter.
- Solitary lesions with a wide base.
- Polyps that exhibit progressive growth.
- Coexistence of gallstones and gallbladder wall thickening, particularly in patients over 60 years of age or with polyps larger than 2 cm in diameter.
For patients without the aforementioned risk factors and who are asymptomatic, routine follow-up is recommended. Regular ultrasound examinations every 6 to 12 months may be performed to monitor changes in polyp size. In contrast, patients with the above risk factors for malignancy or with significant symptoms—after ruling out psychological factors, gastrointestinal diseases (such as gastric or duodenal disorders), and other biliary conditions—are generally advised to undergo surgical treatment.
The recommended surgical approach is laparoscopic cholecystectomy. During surgery, rapid pathological examination is conducted, and in cases where malignancy is detected, further radical surgical excision may be required based on intraoperative findings and pathological analysis. Postoperative paraffin-embedded pathological examination is used to confirm the diagnosis, including disease staging and histopathological grading.