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      We have expanded our resource library so you can now explore content on HER2 in tumors beyond breast.

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  • Breast Cancer
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Investigate challenging cases

Explore in-depth breast cancer clinical case reviews with practical recommendations to aid HER2 IHC assessment.

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The importance of reporting discrete HER2 IHC scores

In this case, the patient presented with primary breast cancer classified as HER2-negative.

by Marilyn Bui, MD, PhD

 
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Focal HER2 expression on IHC 0 breast carcinoma metastatic to the lung

In this case, HER2 IHC on a lung biopsy sample showed focal HER2 expression.

By Gary Tozbikian, MD

 
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Consideration of pre-analytic conditions when assessing sample from metastatic sites

In this case, a core needle biopsy 
from a metastatic site was assessed with HER2 IHC.

By Shi Wei, MD, PhD

 
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Artifacts with low HER2 expression: Cytoplasmic blush

In this case, HER2 IHC on a core biopsy of a right axillary mass showed cytoplasmic staining.

by Hannah Wen, MD, PhD

 
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Assessing HER2 IHC with cytoplasmic staining

In this case, the HER2 IHC on a segmental mastectomy specimen from a primary invasive ductal carcinoma showed an unusual cytoplasmic staining pattern.

by Savitri Krishnamurthy, MD

 
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Assessing HER2 IHC with edge artifacts

In this case, the HER2 IHC of a core needle biopsy specimen from an invasive breast carcinoma showed signs of edge artifact.

by Gary Tozbikian, MD

 
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Interpreting HER2 IHC with an extensive in situ component

In this case, there was an extensive in situ component present along with the invasive carcinoma, and HER2 IHC scores were discordant between the two.

by Hannah Wen, MD, PhD

 
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HER2, human epidermal growth factor receptor 2; IHC, immunohistochemistry.

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Spotlight Series

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The Breast Pathology Faculty share their thoughts on dealing with complexities associated with HER2 IHC assessment.

Decalcified Bone Specimen: Processing Procedures

Decalcified bone specimen: Processing procedures

In this article, Dr. Wei discusses the use of bone specimens as samples for HER2 IHC in metastatic breast cancer.

by Shi Wei, MD, PhD

 
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Unusual Staining Pattern: Basolateral Staining In Micropapillary Carcinoma

Unusual staining pattern: Basolateral staining in micropapillary carcinoma

In this article, Dr. Jaffer details the interpretation of biomarker testing in invasive micropapillary carcinomas.

by Shabnam Jaffer, MD

 
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Impact Of Pre-Analytic Variables On HER2 IHC Results

Impact of pre-analytic variables on HER2 IHC results

In this article, Dr. Khoury reviews several different pre-analytic variables and their impact on HER2 IHC assessment.

by Thaer Khoury, MD

 
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Recommendations For Testing Of Cytology Specimens

Recommendations for testing of cytology specimens

In this article, Dr. Bui discusses the advantages and disadvantages of using cytology samples for HER2 IHC testing in breast cancer.

by Marilyn Bui, MD, PhD

 
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Breast Cancer Resources
Breast Cancer Resources

Breast Cancer Resources

Discover educational materials on HER2 in breast cancer designed to support you in refining HER2 IHC assessment.

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Welcome to HER2Know

This website is intended to help healthcare professionals practicing in the United States find and access scientifically balanced, evidence-based, and peer-led information and professional resources in support of HER2 IHC evaluation. The dissemination of this information may be subject to different medical and regulatory requirements in other countries. This information is provided for educational purposes only. It is not intended for use in the diagnosis or treatment of individual patients. Are you a healthcare professional practicing in the United States?

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