The cytologic diagnosis obtained by brushing or biopsy in malignant biliary strictures is considered to be highly specific but poorly sensitive. The diagnostic association of biliary brushing and bile exfoliate cytology has been suggested but is rarely performed in clinical practice. The objective of this study was to assess the diagnostic performance of bile aspiration associated with biliary brushing during therapeutic endoscopic retrograde cholangiopancreatography (ERCP).
From 2004 to 2009, 239 consecutive patients who underwent ERCP were included in the study. The biliary strictures were considered clinically benign in 26% of patients, uncertain in 25%, and malignant in 49%. The 298 cytologic samples collected were divided in 3 groups: bile aspiration alone (26%), biliary brushing alone (20%), and bile aspiration combined with brushing (54%). The definitive diagnosis of malignancy was obtained by biopsy, surgery, and fine-needle aspiration or was determined by an unfavorable disease course.
The cytologic diagnoses were as follows: 149 samples were benign (50%), 114 were malignant (38%), 34 had atypia (12%), and 1 had no diagnostic value. The procedure output values were as follows: for bile aspiration alone, sensitivity was 56.4%, specificity was 93.9%, the positive predictive value (PPV) was 91.7%, and the negative predictive value (NPV) was 64.6%; for brushing alone, sensitivity was 62.5%, both specificity and the PPV were 100%, and the NPV was 73%; and, for bile aspiration and brushing combined, sensitivity was 81%, both specificity and the PPV were 100%, and the NPV was 75%.
For patients who have symptomatic biliary stricture, bile aspiration during ERCP is a simple and safe procedure. Bile aspiration combined with brushing significantly increases the yield of cytology for malignant biliary tumors (sensitivity, 81%), particularly in cholangiocarcinomas. Cancer Cytopathol 2016;124:330-9. © 2015 American Cancer Society.