Test ID: 19701
Biliary Tract Malignancy, FISH Only
Method Description
Describes how the test is performed and provides a method-specific reference
Biliary cells are harvested, fixed, and placed on a slide. Fluorescently-labeled DNA probes to the centromeres of chromosomes 3, 7, and 17, and to the 9p21 locus (UroVysion, Abbott Molecular, Inc., Des Plaines, IL) are hybridized to the cells on the slide. The slide is then washed and stained with DAPI (a nuclear counterstain). Fluorescence microscopy with unique band filters is used to scan the slide for atypical cells (eg, cells with nuclear enlargement or irregularity). These cells are assessed for gains of chromosomes 3, 7, and 17. Cells with chromosomal gains (polysomy or trisomy) are recorded. If 5 or more cells show polysomy, then the case is considered positive for polysomy. If 10 or more cells show trisomy of 1 of the chromosomes (most often chromosome 7), the case is considered positive for trisomy. (Unpublished Mayo method)
Day(s) and Time(s) Test Performed
Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Friday; 8:00 a.m. to 5:00 p.m.


