Journal Article

Concordance of breast cancer biomarker testing in core needle biopsy and surgical specimens: A single institution experience

Warrior, Surbhi, Fogg, Louis F., Yun, Nicole K., Slostad, Jessica A., Rao, Ruta, Schad, Aimee E.

2022

Overview

Background Accurate diagnostic biomarker testing is crucial to treatment decisions in breast cancer. Biomarker testing is performed on core needle biopsies (CNB) and is often repeated in the surgical specimen (SS) after resection. As differences between CNB and SS testing may alter treatment decisions, we evaluated concordance between CNB and SS as well as associated changes in treatment and clinical outcomes. Methods We performed a retrospective analysis of breast cancer patients at our institution between January 2010 and May 2020. Concordance between CNB and SS was assessed for estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Survival in patients, including recurrence, metastatic recurrence, and death, were assessed using chi‐squared likelihood ratio. Results In total, 961 patients met eligibility criteria. Concordance, minor discordance, total concordance (concordance plus minor discordance), and major discordance between CNB and SS were reported for ER (87.7%, 9.2%, 90.8%, and 2.9%), PR (58.1%, 29.1%, 87.2%, and 12.8%), and HER2 IHC (52.5%, 20.9%, 73.4%, 26.6%), respectively. HER2 FISH concordance and major discordance were 58.5% and 1.2%, respectively. Of major discordance, ER (48.2%, p < 0.001) and HER2 FISH (50.0%) led to more management changes than HER2 IHC (2.4%, p = 0.04) and PR (1.6%, p = 0.10). Patients with ER major discordance had increased risk of death (6.7% concordance vs. 22.2% major discordance, p = 0.004). Conclusion Overall, retesting ER and HER2 was more clinically beneficial than retesting PR. To aid decision‐making and minimize healthcare costs, we propose patient‐centered guidelines on retesting biomarker profiles. Retesting estrogen receptor and HER2 status provides more clinical benefit than retesting progesterone receptor status. We propose guidelines for retesting receptor profiles to aid patient care management decisions, prioritize clinical benefits, and minimize healthcare costs.

• Publisher: John Wiley & Sons, Inc,John Wiley and Sons Inc,Wiley
• Subject: Biomarkers / Biomarkers, Tumor - metabolism / Biopsy / Biopsy, Large-Core Needle / Breast cancer / Breast Neoplasms - diagnosis / Breast Neoplasms - drug therapy / Breast Neoplasms - surgery / Cancer therapies / Chemotherapy / core needle biopsy / Cost control / Decision making / Discordance / Epidermal growth factor / ErbB-2 protein / estrogen receptor / Estrogen receptors / Estrogens / Female / Fluorescence in situ hybridization / Hispanic Americans / Humans / Immunohistochemistry / In Situ Hybridization, Fluorescence / Management decisions / Metastases / Metastasis / Patients / Progesterone / progesterone receptor / Receptor, ErbB-2 - metabolism / Receptors, Estrogen - metabolism / Receptors, Progesterone - metabolism / Retrospective Studies / surgical pathology / tyrosine kinase‐type cell surface receptor (human epidermal growth factor receptor 2 HER2)