HER2 Fluorescence in Situ Hybridization (Colorectal)

Alternative Names/Synonyms	FISH, HER2 FISH, HER2 ISH
Laboratory	Anatomical Pathology
Sub-section	FISH
Test Code	Group Test: HER2CRF

Ordering Instructions, Requisition

In-house: Reflex test following 2+ HER2 IHC score.
Consult: https://www.mountsinai.on.ca/care/pathology/laboratory-forms-and-requisitions/pathology-consult-requisition

Supporting Documents

Ontario Health Guidelines

Clinical Significance (If applicable)

HER2 FISH testing in colorectal cancer is indicated for guiding targeted therapy in advanced or metastatic cases due to its potential therapeutic implications.

Specimen Requirements (Sample Type)

Formalin fixed paraffin embedded block or tissue sections cut at 4 microns mounted on charged or coated slides.

Collection Requirements

Fixation between 6-72 hours

Storage / Shipment Details

Room temperature (block/unstained slide)

Cause for Rejection

Specimen Acceptability and Transport Guidance

Instrument, Methodology

Dako Omnis

Test Availability

Monday to Friday; 8 am - 4 pm

Routine Turnaround Time

Typically 7 days, with a maximum of 14 days

Reference Ranges

Please refer directly to the Pathology Report

Laboratory Contact Information

416-586-4800
Extension 4481 or 3813

Ordering Practices

Reflex testing following a 2+ HER2 IHC score