Sign in →

Test ID: FBILM Biliary Tract Malignancy-Cytology, FISH, Varies

Specimen Required


PreservCyt Vial (T536)

CytoLyt Solution (T564)

Specimen Type: Bile duct brushing, bile duct aspirate, hepatobiliary brushing, or hepatobiliary aspirate

Container/Tube: Separate ThinPrep vial containing 20 mL PreservCyt or CytoLyt solution for each specimen

Specimen Volume: Entire collection

Collection Instructions: Label with site specimen was collected from (eg, right hepatic duct or common bile duct).

Useful For

Assessing bile duct brushing or hepatobiliary brushing specimens for malignancy

Testing Algorithm

When this test is ordered, FISH testing will be performed. When additional specimens are received, the laboratory will add BILMA / Biliary Tract Malignancy, FISH, Specimen A, Varies to the first specimen, BILMB / Biliary Tract Malignancy, FISH, Specimen B, Varies to the second specimen, BILMC / Biliary Tract Malignancy, FISH, Specimen C, Varies to the third specimen, and so on.

Method Name

Cytology Light Microscopy and Fluorescence In Situ Hybridization (FISH)

Reporting Name

Biliary Tract Malignancy-Cyto/FISH

Specimen Type


Specimen Minimum Volume

See Specimen Required

Specimen Stability Information

Specimen Type Temperature Time Special Container
Varies Refrigerated (preferred)

Clinical Information

Endoscopic retrograde cholangiopancreatography (ERCP) is used to examine patients with biliary tract obstruction or stricture for possible malignancy. Biopsies and cytologic specimens are obtained at the time of ERCP. Cytologic analysis complements biopsy by sometimes detecting malignancy in patients with a negative biopsy. Nonetheless, a number of studies suggest that the overall sensitivity of bile duct brushing and bile aspirate cytology is quite low.


Fluorescence in situ hybridization (FISH) is a technique that utilizes fluorescently labeled DNA probes to examine cells for chromosomal alterations. FISH can be used to detect cells with chromosomal changes (eg, aneuploidy) that are indicative of malignancy. Studies in our laboratory indicate that the sensitivity of FISH to detect malignant cells in biliary brush specimens is superior to that of conventional cytology.

Reference Values

Negative for malignancy.


An interpretive report will be provided.


A positive cytology diagnosis is normally definitive for the presence of malignancy.


Suspicious or atypical results need further confirmation by clinical observation, repeat cytology, or perhaps appropriate biopsy.

Clinical Reference

1. Barr Fritcher EG, Voss JS, Brankley SM, et al: An Optimized Set of Fluorescence In Situ Hybridization Probes for Detection of Pancreatobiliary Tract Cancer in Cytology Brush Samples. Gastroenterology 2015;149(7):1813-1824

2. Barr Fritcher EG, Kipp BR, Voss JS, et al: The Development of a Tailored Pancreatobiliary Fluorescence in situ Hybridization (FISH) Assay to Improve Detection of Malignancy in Pancreatobiliary Brushings. J Mol Diagn 2013;15(6):909

3. Barr Fritcher EG, Kipp BR, Halling KC, et al: A multivariable model using advanced cytologic methods for the evaluation of indeterminate pancreatobiliary strictures. Gastroenterology 2009;136(7):2180-2186

Day(s) and Time(s) Performed

Monday through Friday; 8 a.m.-5 p.m.

Analytic Time

7 days

Test Classification

This test was developed using an analyte specific reagent. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.

CPT Code Information


88377-BILMA/BILMB/etc (if appropriate)

LOINC Code Information

Test ID Test Order Name Order LOINC Value
FBILM Biliary Tract Malignancy-Cyto/FISH 95230-9


Result ID Test Result Name Result LOINC Value
71291 Interpretation 69965-2
71292 Participated in the Interpretation No LOINC Needed
71293 Report electronically signed by 19139-5
71294 Addendum 35265-8
71295 Gross Description 22634-0
CY070 Collection Procedure 33724-6
CY042 Source 22633-2
CY043 Clinical History 22636-5
CY044 Fixative 8100-0
71570 Disclaimer 62364-5
71816 Case Number 80398-1

Reflex Tests

Test ID Reporting Name Available Separately Always Performed
BILMB Biliary Tract Malignancy, FISH No No
BILMC Biliary Tract Malignancy, FISH No No
BILMD Biliary Tract Malignancy, FISH No No
BILME Biliary Tract Malignancy, FISH No No
BILMF Biliary Tract Malignancy, FISH No No

Additional Tests

Test ID Reporting Name Available Separately Always Performed
BILMA Biliary Tract Malignancy, FISH No Yes