Significant factors influencing the accuracy of bile cytology for gallbladder lesions

Abstract

Objective: To identify factors influencing the diagnostic accuracy of bile cytology for gallbladder lesions.
Study design: We retrospectively reviewed a series of 1245 cytologic specimens from 265 patients. We investigated the factors affecting the differences in method of obtaining bile. We also evaluated the correlation between the diagnostic accuracy of bile cytology and pathological factors including locations, and both macroscopic and histological types of the lesions in 25 patients who had undergone surgical resection of gallbladder carcinoma.
Results: 1. The overall sensitivity of bile cytology for gallbladder cancer was 67.3%. 2. Increasing numbers of cytologic specimens correlated with a higher rate of positivity although the frequency of cytologic examinations was not the only factor influencing diagnostic accuracy. 3. Numbers of specimens examined in false-negative cases tended to be fewer than those in positive cases. 4. The positive ratio per examination was 38.1% in cancer-bearing patients. 5. Based on method of obtaining bile, the positivity was 66.7% with ENBD, 64.2% with PTBD, and 76.0% with PTGBD. 6. Lower sensitivity was observed in cytologic specimens from macroscopically papillary and histologically well differentiated carcinomas.
Conclusion: In bile cytology for gallbladder lesions, the choice of method for obtaining bile and the number of specimens will affect the results.