Biliary Brush Cytology Revisited

Abstract

Purpose: To evaluate the diagnostic yield of biliary brush cytology and the factors affecting positive results in patients with biliary strictures. Patients and Methods: The medical records of all patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) with biliary brush cytology at our institution from November 2004 to December 2013 were reviewed in this retrospective study. The yield of positive brush cytology and the factors affecting positive yield, such as stricture location, age, gender and preprocedure CA 19.9 level were assessed. The final histopathology, diagnosis obtained by other methods, such as endoscopic ultrasound-guided fine-needle aspiration cytology, CT scan, Tru-Cut biopsy and/or clinical/radiological follow-up were used to identify true- and false-positive/negative results. The brush cytology results were divided into 4 main categories: malignant, benign, atypical cells and inadequate. Results: A total of 1,168 patients underwent ERCP during this 9-year period. Out of these, 142 patients had ERCP and biliary brushings for diagnosis. The mean age of the patients at presentation was 58.7 years (range 23-84 years; 64.8% males). The indication for referral was obstructive jaundice in all patients. Of the 142 patients, 77 (54.2%) had a distal common bile duct (CBD) stricture and 65 (45.8%) had a proximal /complex hilar stricture. The strictures were classified as proximal or distal, based on their relationship with the cystic duct; those below the cystic duct insertion were classified as distal and those above it were considered proximal. The diagnostic yield of brush cytology was 58.5%. The diagnostic yield was higher for proximal than for distal CBD strictures (67 vs. 50%; p = 0.047). It was also higher for females (58 vs. 57.6%; p = 0.94), patients >50 years (60 vs. 50%; p = 0.29) and those with a CA 19.9 level >300 IU/ml (59.4 vs. 55.5%; p = 0.65) but did not reach statistical significance for any of these parameters. Complete follow-up data were available for 96 patients and 46 patients were lost to follow-up. The sensitivity, specificity, positive predictive value and negative predictive value were 65.3, 100, 100 and 27%, respectively. When patients with atypia were included in the group with positive results, the diagnostic yield increased to 65.5% with a diagnostic sensitivity of 68.6%. There were 27 false-negative diagnoses, 10 patients were true-negative and no patients had a false-positive diagnosis. Conclusion: Biliary brush cytology is a safe and simple initial diagnostic procedure in patients with biliary strictures and can be performed at the time of therapeutic ERCP. If performed correctly and then interpreted by a dedicated cytopathologist, it has a good diagnostic yield and sensitivity. We feel that the low rates of success with this technique reported in some earlier studies have led to a feeling that this is not a particularly useful technique. We recommend that this topic should be revisited, and that the technique should be used more often.

The value of DNA image cytometry combined with brush routine cytology in diagnosing indeterminate biliary strictures: A large sample size retrospective study

“…Because of their deep anatomical position, obtaining tissues from proximal strictures is more technical, and the cell volume obtained from proximal strictures is theoretically less than that obtained from distal strictures with the instruments used during ERCP because the intrahepatic bile duct is less accessible. However, in studies, the conclusions were varied . Our study identified that the diagnostic accuracy between proximal and distal strictures was not significantly different for RC and the combination of two methods.…”

Outcomes of Different Methods for Analysis of Biliary Brush Cytology and of Factors Associated with Positive Diagnosis in an Age-Dependent Retrospective Review

“…Although biliary brush cytology is the most widely used tissue sampling technique, it has been associated with modest sensitivity in a large number of studies [3, 18, 21]. The current literature indicates a diagnostic sensitivity for cancer detection ranging from 6 to 65% [1, 10-22]. In a 10-year review of the literature, Burnett et al [21] identified 16 studies (involving a total of 1,556 patients).…”

“…In contrast, higher sensitivities were reported by Urbano et al [19], Arvanitakis et al [20], and Temiño López-Jurado et al [10] (65, 63, and 61%, respectively). Several factors have been highlighted to explain this large variability in sensitivity, such as the endoscopic technique, type of brush, use of dilatation and basket, cytological techniques, and cytological criteria for malignancy, interpathologist variation for biliary cytology interpretation, patient age, and the type, localization, and length of the tumor [1, 10, 13, 15, 18, 21, 22, 24]. In the current study, we found an overall sensitivity of 52.5%, a result in line with the previous literature.…”

“…However, the most commonly used strategy to obtain a tissue sample of the stricture is brush cytology during endoscopic retrograde cholangiopancreatography (ERCP). Brush cytology is a technique with a low complication rate, widespread availability, relative ease of performance, and the ability to sample nearly the entire biliary tree [1, 10-22]. However, the diagnostic accuracy of the technique is relatively low, ranging from 5.9 to 65% [1, 10-22].…”

“…Brush cytology is a technique with a low complication rate, widespread availability, relative ease of performance, and the ability to sample nearly the entire biliary tree [1, 10-22]. However, the diagnostic accuracy of the technique is relatively low, ranging from 5.9 to 65% [1, 10-22]. In a recent review of the literature from 2002 until 2012, including 16 studies and 1,556 patients, biliary brushing cytology was found to be associated with an overall sensitivity of 41.6% and a negative predictive value (NPV) of 58% [23].…”