Is there a role for growth status in distinguishing gallbladder adenomas from cholesterol polyps? – A retrospective study based on 520 cholecystectomy patients

Gallbladder adenomas have cancerous potential and occur in 4–8.9% of gallbladder polyps. The growth status (size progression and growth rate during follow-up) of polyps and their effectiveness for predicting adenomas are poorly defined. Herein, we compared adenomas and cholesterol polyps based on the growth status and evaluated the reported risk factors in predicting neoplasm. We enrolled 520 patients who underwent preoperative ultrasonic follow-up more than 6 months with post-cholecystectomy pathologically confirmed gallbladder polyps. The patients were classified into adenoma and cholesterol polyp groups. Growth status, clinical characteristics, laboratory data, ultrasonic findings were reviewed and compared between the groups. Seventy-nine adenomas and 441 cholesterol polyps were analyzed. The mean diameter of adenomas (cholesterol polyps) was 7.24 ± 4.36 mm (6.23 ± 2.88 mm) in the initial and 12.06 ± 4.61 mm (10.05 ± 2.95 mm) in the preoperative examination. The median size progression (range) of polyps in the cholesterol polyps [3 (0, 22)] mm was smaller than that in adenomas [4 (0, 21)] mm (p = .075). The mean growth rate of adenomas (1.07 ± 1.33 mm/6 months) was slightly faster than in cholesterol polyps (0.83 ± 1.04 mm/6 months) (p = .338). The indicators significantly associated with adenomas were age >49.5 years, lack of gallbladder polyps/cholelithiasis family history, polyp size >11.5 mm and solitary polyp (p = .005, p = .027, p = .001, and p = .021, respectively). Growth status was not a valuable modality to distinguishing gallbladder adenomas from cholesterol polyps. Risk factors such as age, polyp size, and solitary polyp were effective in predicting adenomas.