Authors' objectives:

The aim of this report is:

1) To systematically review the literature on the validity and reliability of immunohistochemistry (IHC) and fluorescence in-situ hybridization (FISH).

2) To carry out a cost-effectiveness analysis to compare various testing strategies based on IHC and FISH.

Authors' results and conclusions: A total of 18 studies satisfied the inclusion criteria. Most studies evaluated the PathVysionTM FISH assay and HercepTestTM IHC assay. The percentage of patients in each IHC score category (median) was estimated as - IHC 0: 36.1, IHC 1+: 35.5, IHC 2+: 12.2, IHC 3+: 16.2. The percentage of positive FISH results (median) among the 4 IHC categories was estimated as - IHC 0: 1.7, IHC 1+: 3.4, IHC 2+: 29.9, 3+: 91.9. In general, studies of reliability between/within observers/laboratories, concluded that the reliability of FISH was better than for IHC. However, there was evidence that FISH neither had 100% sensitivity and specificity nor 100% reliability. The currently pursued strategy of confirmatory testing for 2+ cases alone was expected to correctly diagnose 310 of 320 (96.9%) women.

Authors' recommendations: With the current arrangement for FISH testing external to the MUHC, the most cost-effective strategy is to screen all patients with IHC, followed by confirmatory testing with FISH of those patients with IHC scores of 2+ or 3+. Purchase of new equipment may be justified if it is decided to test all patients with FISH. Recommendation: If it is assumed that trastuzumab therapy will be offered, it is recommended that all breast cancer cases be screened with IHC and those who have scores of 2+ or 3+ be tested by FISH to confirm their HER2 positive status. In the unusual event that a breast cancer patient approaches the hospital with a positive FISH test carried out outside the MUHC, an IHC test needs to be carried out to confirm the course of action.

Authors' methods: Review

Project Status: Completed

URL for project: http://www.mcgill.ca/files/tau/HER2reportdraft4finalMay2006.pdf

Year Published: 2006

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Canada

Organisation Name: Technology Assessment Unit of the McGill University Health Centre (MUHC)

Contact Address: Technology Assessment Unit of the MUHC, 536-5100 Boul. Maisonneuve O, Montreal, H4A 3T2

Contact Name: eva.suarthana@mcgill.ca

Contact Email: nisha.almeida@muhc.mcgill.ca

Copyright: Technology Assessment Unit of the McGill University Health Centre (MUHC)