Gallbladder carcinoma: intraoperative imprint cytology, a helpful and valuable screening procedure

A major problem arises when a tumor is not readily recognized at the time of cholecystectomy. A carcinoma at early stages or one hidden by acute or chronic inflammation can be overlooked during surgery, and the diagnosis would then be made only after microscopic examination of paraffin-embedded tissue. The purpose of the present report is to communicate the results of 10 years' experience with the use of imprint cytology for the intraoperative diagnosis of gallbladder carcinoma.

During the period June 1994 to June 2004, 525 imprint cytologies of gallbladder mucosa were performed after 160 open cholecystectomies and 365 laparoscopic cholecystectomies. The patients had been operated on for acute or chronic cholecystitis due to lithiasis. Only 18 patients had a preoperative diagnosis of gallbladder carcinoma. The sensitivity, specificity, predictive values, accuracy, and their confidence intervals (95% CIs), of intraoperative imprint cytology for the diagnosis of carcinoma were analyzed.

The average time employed for each procedure was 10 min. Patients' mean age was 69.2 years with a range of 24 to 92 years. Three hundred and forty-two patients (65.1%) were women and 183 (34.9%) were men. The imprint cytology method was positive in 44 of 58 gallbladder carcinomas diagnosed, with a sensitivity of 75.9% (44/58 patients) and a specificity of 99.8% (466/467). Only 1 case (1/525; 0.2%) was a false-positive; this was due to reactive changes. The positive predictive value was 97.8% (44/45; 95% CI = 86.8-99.9), negative predictive value was 97.1% (466/480; 95% CI = 95.0-98.3), and accuracy was 97.1% ([44 + 466]/525; 95% CI = 95.2-98.3). There was insufficient or inadequate material in 4 cases.

Imprint cytology of the gallbladder mucosa is an easy, rapid, and high-quality method for detecting gallbladder carcinoma.