HER-2/neu amplification testing in breast cancer by Multiplex Ligation-dependent Probe Amplification: Influence of manual- and laser microdissection

Cathy B. Moelans, Roel A. de Weger, Chantal Ezendam, Paul J. van Diest

Research output: Contribution to journalArticle

Abstract

Background: Accurate assessment of HER-2/neu status is crucial for proper prognostic information and to offer direct appropriate treatment for breast cancer patients. Next to immunohistochemistry (IHC) to evaluate HER2 protein overexpression, a second line gene amplification test is generally deemed necessary for cases with equivocal protein expression. Recently, a new PCR based test, called Multiplex Ligation-dependent Probe Amplification (MLPA), was introduced as a simple and quick method to assess HER-2/neu gene amplification status in invasive breast cancer. MLPA was previously shown to correlate well with IHC and in situ hybridization (ISH), but a low tumor percentage in the tissue tested could negatively affect the accuracy of MLPA results. Methods: To examine this, MLPA was repeated in 42 patients after serial H&E section guided manual dissection with a scalpel and after laser microdissection of the tumor. Results: Both dissection techniques led to higher HER2 gene copy numberratios and thereby made MLPA more quantitative. Concordance between MLPA and ISH improved from 61% to 84% after manual microdissection and to 90% after laser microdissection. Conclusion: Manual and laser microdissection similarly increase the dynamic range of MLPA copy number ratios which is a technical advantage. As clinically a dichotomization between normal and amplified suffices and MLPA is relatively unsensitive to tumor content, microdissection before MLPA may not be routinely necessary but may be advisable in case of very low tumor content (≤30%), when MLPA results are equivocal, or when extensive ductal carcinoma in situ is present. Since differences between manual and laser microdissection were small, less time consuming manual microdissection appears to be sufficient.

Original languageEnglish (US)
Article number4
JournalBMC Cancer
Volume9
DOIs
StatePublished - Jan 5 2009
Externally publishedYes

Fingerprint

Microdissection
Multiplex Polymerase Chain Reaction
Lasers
Breast Neoplasms
erbB-2 Genes
Gene Amplification
In Situ Hybridization
Dissection
Neoplasms
Immunohistochemistry
Carcinoma, Intraductal, Noninfiltrating
Laser Therapy
Proteins
Polymerase Chain Reaction

ASJC Scopus subject areas

  • Oncology
  • Cancer Research
  • Genetics

Cite this

HER-2/neu amplification testing in breast cancer by Multiplex Ligation-dependent Probe Amplification : Influence of manual- and laser microdissection. / Moelans, Cathy B.; de Weger, Roel A.; Ezendam, Chantal; van Diest, Paul J.

In: BMC Cancer, Vol. 9, 4, 05.01.2009.

Research output: Contribution to journalArticle

@article{b65e7c2210334a3a9581fab646723de9,
title = "HER-2/neu amplification testing in breast cancer by Multiplex Ligation-dependent Probe Amplification: Influence of manual- and laser microdissection",
abstract = "Background: Accurate assessment of HER-2/neu status is crucial for proper prognostic information and to offer direct appropriate treatment for breast cancer patients. Next to immunohistochemistry (IHC) to evaluate HER2 protein overexpression, a second line gene amplification test is generally deemed necessary for cases with equivocal protein expression. Recently, a new PCR based test, called Multiplex Ligation-dependent Probe Amplification (MLPA), was introduced as a simple and quick method to assess HER-2/neu gene amplification status in invasive breast cancer. MLPA was previously shown to correlate well with IHC and in situ hybridization (ISH), but a low tumor percentage in the tissue tested could negatively affect the accuracy of MLPA results. Methods: To examine this, MLPA was repeated in 42 patients after serial H&E section guided manual dissection with a scalpel and after laser microdissection of the tumor. Results: Both dissection techniques led to higher HER2 gene copy numberratios and thereby made MLPA more quantitative. Concordance between MLPA and ISH improved from 61{\%} to 84{\%} after manual microdissection and to 90{\%} after laser microdissection. Conclusion: Manual and laser microdissection similarly increase the dynamic range of MLPA copy number ratios which is a technical advantage. As clinically a dichotomization between normal and amplified suffices and MLPA is relatively unsensitive to tumor content, microdissection before MLPA may not be routinely necessary but may be advisable in case of very low tumor content (≤30{\%}), when MLPA results are equivocal, or when extensive ductal carcinoma in situ is present. Since differences between manual and laser microdissection were small, less time consuming manual microdissection appears to be sufficient.",
author = "Moelans, {Cathy B.} and {de Weger}, {Roel A.} and Chantal Ezendam and {van Diest}, {Paul J.}",
year = "2009",
month = "1",
day = "5",
doi = "10.1186/1471-2407-9-4",
language = "English (US)",
volume = "9",
journal = "BMC Cancer",
issn = "1471-2407",
publisher = "BioMed Central",

}

TY - JOUR

T1 - HER-2/neu amplification testing in breast cancer by Multiplex Ligation-dependent Probe Amplification

T2 - Influence of manual- and laser microdissection

AU - Moelans, Cathy B.

AU - de Weger, Roel A.

AU - Ezendam, Chantal

AU - van Diest, Paul J.

PY - 2009/1/5

Y1 - 2009/1/5

N2 - Background: Accurate assessment of HER-2/neu status is crucial for proper prognostic information and to offer direct appropriate treatment for breast cancer patients. Next to immunohistochemistry (IHC) to evaluate HER2 protein overexpression, a second line gene amplification test is generally deemed necessary for cases with equivocal protein expression. Recently, a new PCR based test, called Multiplex Ligation-dependent Probe Amplification (MLPA), was introduced as a simple and quick method to assess HER-2/neu gene amplification status in invasive breast cancer. MLPA was previously shown to correlate well with IHC and in situ hybridization (ISH), but a low tumor percentage in the tissue tested could negatively affect the accuracy of MLPA results. Methods: To examine this, MLPA was repeated in 42 patients after serial H&E section guided manual dissection with a scalpel and after laser microdissection of the tumor. Results: Both dissection techniques led to higher HER2 gene copy numberratios and thereby made MLPA more quantitative. Concordance between MLPA and ISH improved from 61% to 84% after manual microdissection and to 90% after laser microdissection. Conclusion: Manual and laser microdissection similarly increase the dynamic range of MLPA copy number ratios which is a technical advantage. As clinically a dichotomization between normal and amplified suffices and MLPA is relatively unsensitive to tumor content, microdissection before MLPA may not be routinely necessary but may be advisable in case of very low tumor content (≤30%), when MLPA results are equivocal, or when extensive ductal carcinoma in situ is present. Since differences between manual and laser microdissection were small, less time consuming manual microdissection appears to be sufficient.

AB - Background: Accurate assessment of HER-2/neu status is crucial for proper prognostic information and to offer direct appropriate treatment for breast cancer patients. Next to immunohistochemistry (IHC) to evaluate HER2 protein overexpression, a second line gene amplification test is generally deemed necessary for cases with equivocal protein expression. Recently, a new PCR based test, called Multiplex Ligation-dependent Probe Amplification (MLPA), was introduced as a simple and quick method to assess HER-2/neu gene amplification status in invasive breast cancer. MLPA was previously shown to correlate well with IHC and in situ hybridization (ISH), but a low tumor percentage in the tissue tested could negatively affect the accuracy of MLPA results. Methods: To examine this, MLPA was repeated in 42 patients after serial H&E section guided manual dissection with a scalpel and after laser microdissection of the tumor. Results: Both dissection techniques led to higher HER2 gene copy numberratios and thereby made MLPA more quantitative. Concordance between MLPA and ISH improved from 61% to 84% after manual microdissection and to 90% after laser microdissection. Conclusion: Manual and laser microdissection similarly increase the dynamic range of MLPA copy number ratios which is a technical advantage. As clinically a dichotomization between normal and amplified suffices and MLPA is relatively unsensitive to tumor content, microdissection before MLPA may not be routinely necessary but may be advisable in case of very low tumor content (≤30%), when MLPA results are equivocal, or when extensive ductal carcinoma in situ is present. Since differences between manual and laser microdissection were small, less time consuming manual microdissection appears to be sufficient.

UR - http://www.scopus.com/inward/record.url?scp=59249106279&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=59249106279&partnerID=8YFLogxK

U2 - 10.1186/1471-2407-9-4

DO - 10.1186/1471-2407-9-4

M3 - Article

C2 - 19123950

AN - SCOPUS:59249106279

VL - 9

JO - BMC Cancer

JF - BMC Cancer

SN - 1471-2407

M1 - 4

ER -