HER2Know Logo
HER2Know Logo
  • Tumor Types
    • Welcome to the new, updated HER2Know

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

      Looking for the original HER2Know breast cancer resources?

      • Breast Cancer
        • Breast Cancer Overview
        • Breast Cancer Resources
        • IHC Atlas
        • Pathologists' Perspectives
          • Clinical Case Reviews
          • Spotlight Series
        • Knowledge Check
      • Gastric Cancer
        • Gastric Cancer Overview
        • Gastric Cancer Resources
        • Gastric Cancer IHC Atlas
      • Other Solid Tumors
        • Other Solid Tumors Overview
        • Other Solid Tumors Resources
        • Other Solid Tumors IHC Atlas
       
  • Resources
  • IHC Atlas
  • Contributors
  • In the Know
  • Subscribe
  • TUMOR TYPES
  • Breast Cancer
    • Breast Cancer Overview
    • Breast Cancer Resources
    • IHC Atlas
    • Pathologists' perspectives
    • Clinical Case Reviews
    • Spotlight Series
    • Knowledge Check
  • Gastric Cancer
    • Gastric Cancer Overview
    • Gastric Cancer Resources
    • Gastric Cancer IHC Atlas
  • Other Solid Tumors
    • Other Solid Tumors Overview
    • Other Solid Tumors Resources
    • Other Solid Tumors IHC Atlas
  • Resources
  • IHC Atlas
  • Contributors
  • In the Know
  • Subscribe

Explore the evolution
of HER2 IHC testing

Explore the evolution of
HER2 IHC
testing

HER2 IHC testing is critical for guiding clinical decisions in breast, gastric, and other solid tumors.1,2 With evolving clinical advancements, ensuring scoring consistency across the full spectrum of HER2 expression is more important than ever.2

Explore real-world cases, assessment tools, and expert-developed resources to enhance your HER2 IHC scoring confidence.

IHC Atlas: Whole slide images

Examine real-world staining patterns across 100+ expert-selected cases to support scoring accuracy and diagnostic consistency in your practice.

Explore the IHC Atlas

1 / 4

FEATURED

CAP Breast Biomarker Reporting Template Update

The latest CAP template for reporting results of biomarker testing of specimens from patients with carcinoma of the breast.3

Learn more Cap reporting template

2 / 4

FEATURED

Assessment of HER2 IHC in breast cancer: The lower end of HER2 expression

Shabnam Jaffer, MD, provides a microscopy review of HER2 IHC slide images, focusing on differentiating between HER2 IHC scores at the lower end of the spectrum.

View here

3 / 4

FEATURED

The evolving landscape of HER2: Best practices for clinical sign-out

A video overview of best practices for pathologists when evaluating breast cancer specimens with lower levels of HER2 expression.

Play animation

4 / 4

FEATURED

Spectrum of HER2 expression: Overview and clinical significance

An overview of testing, prevalence, survival, and treatment algorithms for patients with HER2-low metastatic breast cancer.

Play animation
  1. Learn - Option 1
  2. Review - Option 1
  3. Test - Option 1
  4. Plan - Option 1

CAP, College of American Pathologists; HER2, human epidermal growth factor receptor 2; IHC, immunohistochemistry.

1. Ko HC, et al. Front Oncol 2025;15:1565872. doi: 10.3389/fonc.2025.1565872. 2. Zhang H, et al. Histopathology 2024;85(1):3-19. 3. CAP. Reporting Template for Reporting Results of Biomarker Testing of Specimens from Patients with Carcinoma of the Breast. Version: 1.6.0.0.

1. Ko HC, et al. Front Oncol 2025;15:1565872. doi: 10.3389/fonc.2025.1565872. 2. Zhang H, et al. Histopathology 2024;85(1):3-19. 3. CAP. Reporting Template for Reporting Results of Biomarker Testing of Specimens from Patients with Carcinoma of the Breast. Version: 1.6.0.0.

Her2know Footer Logo

Quick Links

  • Subscribe
  • Resources
  • Contributors

 

Breast Cancer Links

  • Breast Cancer Overview
  • Breast Cancer Resources
  • IHC Atlas
  • Clinical Case Reviews
  • Spotlight Series
  • Knowledge Check

 

Gastric Cancer Links

  • Gastric Cancer Overview
  • Gastric Cancer Resources

About Us

  • Contact Us
  • Request Medical Follow-Up
  • AstraZeneca
  • AZ Medical
  • Daiichi Sankyo Company
  • DSI Medical
  • Your Privacy Choices Privacy Options Icon

Legal

  • Privacy Notice
  • Cookie Preferences
  • Legal Notices & Terms of Use
  • Consumer Health Data Privacy Notice
.
AstraZeneca Footer Logo

©2025 Daiichi Sankyo, Inc. and AstraZeneca
US-84238, PP-US-8201a-1849; PP-US-8201a-2276, US-98135 03/25

Her2know Footer Logo

Request an AstraZeneca Medical Affairs Representative Follow-Up

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?

I am a Daiichi Sankyo Company or AstraZeneca authorized person

What is a Daiichi Sankyo Company or AstraZeneca authorized person?

This website is only intended for healthcare professionals practicing in the United States and authorized Daiichi Sankyo Company or AstraZeneca personnel. US Headquarters personnel and US Field Medical personnel are authorized to browse and search the database for their own background knowledge and insight. This website is not intended for use by US Field Sales personnel. None of the content of this site should be directly linked or distributed without approval.

Self Certification Buttons
No, take me to AstraZeneca.com Self Certification Buttons