BACKGROUND
Gallbladder adenoma is a relatively rare benign tumor with a potential for malignant transformation if found to be greater than 1 cm in size.
CASE SUMMARY
Herein, we report a case of a 51-year-old female with large 3 cm × 3 cm mass of gallbladder adenoma that was misdiagnosed as adenocarcinoma due to its clinical presentation. Computed tomography and magnetic resonance imaging scans showed an irregularly shaped cauliflower-like lump in the gallbladder measuring 38 mm × 32 mm corresponding to a malignant tumor and several gallbladder stones with low diffusion-weighted imaging and equisignal of T1-weighted imaging and T2-weighted imaging; moreover, the CA 19-9 levels were very high (184.1 U/mL). Pathology reports after tumor resection showed adenoma with moderate epithelial atypia and moderate atypia in the focal area with fine pedicle and no clear infiltration.
CONCLUSION
Computed tomography and magnetic resonance imaging scans need to be carefully scrutinized in certain rare cases of adenomas with abnormal imaging features.