A 79-year-old man had a chest x-ray because of a history of smoking. However, a calcified gallbladder was noted. This was confirmed by CAT scan. The patient is asymptomatic and has no medical illnesses. The next step in the management of this patient should be:

Due to the high rate of carcinoma (up to 50% of cases) found in patients with calcified gallbladders, cholecystectomy is indicated. A biopsy would not be helpful because of the possibility of missing the tumor. A negative biopsy would not rule out cancer. A pancreaticoduodenectomy is not part of the treatment of gallbladder cancer. Cholecystostomy (tube drainage of the gallbladder) would not help the patient.