Differences between images of large adenoma and protruding type of gallbladder carcinoma.

The aim of this study was to investigate the differences between images of large adenoma of the gallbladder and the protruding type carcinoma of the gallbladder. A retrospective study was performed on 130 patients who underwent cholecystectomy or biopsy for gallbladder polypoid lesions larger than 10 mm; among them, 20 patients were malignant and 110 patients were benign. Patients' details including ultrasonography (US), computed tomography (CT) and magnetic resonance (MR) findings were analyzed. All patients whose lesions were >15 mm by US, had CT or MR scans to further determine the nature of the lesion; two patients who were suspected to have a malignant lesion due to their large tumor size were benign by histological examination. Distinct differences were found between large adenoma and protruding type of gallbladder carcinoma. There were distinct differences between adenomas and the protruding type gallbladder cancers, and there was a pathological basis for the differences. Benign tumors had a more homogeneous texture, had spaces between the tumor and the gallbladder wall and a relatively normal configuration of the gallbladder wall. Based on these findings, certain lesions could be definitively diagnosed as benign adenomas and could help in treatment strategy.