Ultrasound-guided percutaneous transhepatic fine needle aspiration cytology study of gallbladder polypoid lesions.

Abstract

To determine the accuracy and safety of ultrasound (US)-guided percutaneous transhepatic fine needle aspiration cytology (PT FNAC) in the diagnosis of large gallbladder (GB) polyps, especially cholesterol polyps. Between January 1993 and April 1995, 17 patients with GB polyps of a size over 1 cm were examined preoperatively with US-guided PT FNAC, with needle aspiration from the center of the polyps. A cytological-histopathological correlation study was performed postoperatively to assess the accuracy of the PT FNAC results. 1) All eight cholesterol polyps were accurately diagnosed with the PT FNAC alone, showing foamy histiocytes. 2) In five patients, a diagnosis of epithelial tumor was made with PT FNAC study, showing the presence of columnar epithelium, but the PT FNAC failed to detect focal malignant change in adenomas of three of these patients. Only one case of adenocarcinoma was correctly diagnosed preoperatively by the PT FNAC. 3) The PT FNAC failed to detect an inflammatory polyp in one patient. 4) Failed cytology study was encountered in three patients-only bile was aspirated out. One patient had a GB stone, misdiagnosed as a GB polyp, another had an adenomyoma, and the last patient had chronic cholecystitis with Rokitansky-Aschoff sinuses. 5) One complication occurred-mild bile peritonitis. US-guided PT FNAC directly targeting the GB lesions seems accurate in the diagnosis of cholesterol polyps, and is a safe procedure.