bright-field in situ hybridization

HER2 amplification detection

HER2 gene amplification or overexpression occurs in 15% to 25% of breast cancers and has implications for treatment and prognosis. The most commonly used methods for HER2 testing are fluorescence in situ hybridization (FISH) and immunohistochemistry.

FISH is considered to be the reference standard and more accurately predicts response to trastuzumab, but is technically demanding, expensive, and requires specialized equipment.

In situ hybridization is required to be eligible for adjuvant treatment with trastuzumab in Australia.

Bright-field in situ hybridization is an alternative to FISH and uses a combination of in situ methodology and a peroxidase-mediated chromogenic substrate such as diaminobenzidine [chromogenic in situ hybridization (CISH)] or multimer technology coupled with enzyme metallography [silver-enhanced in situ hybridization (SISH)] to create a marker visible under bright-field microscopy.

CISH was introduced into diagnostic testing in Australia in October 2006. SISH methodology is a more recent introduction into the testing repertoire. An evaluation of CISH and SISH performance to assess patient outcome were performed using tissue microarrays.

References

 Establishment of the Australian in situ hybridization program for the assessment of HER2 amplification in breast cancer: a model for the introduction of new biomarkers into clinical practice. Farshid G, Armes JE, Bell R, Cummings M, Fox S, Francis G, Haswell M, Morey A, McCue G, Raymond W, Robbins P, Bilous M. Diagn Mol Pathol. 2010 Dec;19(4):187-93. PMID: 21052003

 Development of automated brightfield double in situ hybridization (BDISH) application for HER2 gene and chromosome 17 centromere (CEN 17) for breast carcinomas and an assay performance comparison to manual dual color HER2 fluorescence in situ hybridization (FISH). Nitta H, Hauss-Wegrzyniak B, Lehrkamp M, Murillo AE, Gaire F, Farrell M, Walk E, Penault-Llorca F, Kurosumi M, Dietel M, Wang L, Loftus M, Pettay J, Tubbs RR, Grogan TM. Diagn Pathol. 2008 Oct 22;3:41. PMID: 18945356 [Free]

 Development of automated brightfield double in situ hybridization (BDISH) application for HER2 gene and chromosome 17 centromere (CEN 17) for breast carcinomas and an assay performance comparison to manual dual color HER2 fluorescence in situ hybridization (FISH). Nitta H, Hauss-Wegrzyniak B, Lehrkamp M, Murillo AE, Gaire F, Farrell M, Walk E, Penault-Llorca F, Kurosumi M, Dietel M, Wang L, Loftus M, Pettay J, Tubbs RR, Grogan TM. Diagn Pathol. 2008 Oct 22;3:41. PMID: 18945356 [Free]

 Bright-field in situ hybridization for HER2 gene amplification in breast cancer using tissue microarrays: correlation between chromogenic (CISH) and automated silver-enhanced (SISH) methods with patient outcome. Francis GD, Jones MA, Beadle GF, Stein SR. Diagn Mol Pathol. 2009 Jun;18(2):88-95. PMID: 19430296