DIAGNOSIS OF MALIGNANT OBSTRUCTIVE-JAUNDICE BY BILE CYTOLOGY - RESULTS IMPROVED BY DILATING THE BILE-DUCT STRICTURES

The disruption of malignant biliary strictures by dilation could enhance the results of bile cytology. To test this hypothesis, we studied the results of bile cytology in 64 consecutive patients undergoing endoscopic biliary drainage for malignant biliary strictures. Patients included 36 men and 28 women, ages 29 to 79 years. In the control group (n = 15), bile was obtained by aspiration without dilating the biliary stricture. In the dilated group (n = 49), bile was aspirated after dilating the biliary stricture to 10F gauge. The bile was centrifuged, and smears were prepared, stained, and interpreted as malignant, suggestive of malignancy, or not malignant. The biliary obstruction was caused by gallbladder cancer in 33, primary bile duct cancer in 14, pancreatic cancer in 11, and metastasis in 6 patients. Forty patients had obstruction at the bifurcation of the hepatic duct. Malignancy was confirmed by surgery in 14, fine-needle aspiration cytology in 9, presence of metastasis in 19, and a combination of clinical and radiologic studies, endoscopic cholangiopancreatography findings, elevated tumor markers, and follow-up in 22 patients. Bile cytology was positive for malignancy in 4 (26.6%) and 31 (63.3%), suggestive in 1 (6.7%) and 6 (12.2%), and negative in 10 (66.7%) and 12 (24.5%) patients in the control group and the dilated group, respectively (p = 0.028, 95% CI 1.15 and 21.03). Cytology was positive in 73% of gallbladder cancers, 62.5% of bile duct cancers, 40% of pancreatic cancers, and 60% of metastasized cancers after dilation. Two patients had hemobilia, 8 had cholangitis, and 2 had pancreatitis after biliary drainage. We conclude that dilation of malignant biliary strictures to 10F gauge enhances the sensitivity of bile cytology.