Suboptimal concordance in testing and retesting results of triple-negative breast carcinoma cases among laboratories: one institution experience

Jose De Jesus; Marilin Rosa

doi:10.1186/s12935-019-0987-7

Suboptimal concordance in testing and retesting results of triple-negative breast carcinoma cases among laboratories: one institution experience

Cancer Cell Int. 2019 Oct 11:19:263. doi: 10.1186/s12935-019-0987-7. eCollection 2019.

Authors

Jose De Jesus¹, Marilin Rosa¹

Affiliation

¹ Department of Anatomic Pathology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612 USA.

Abstract

Background: Triple-negative breast carcinoma (TNBC) patients do not benefit from hormone- or human epidermal growth factor receptor 2- (HER2-) targeted therapies. Accurate testing is pivotal for these patients.

Methods: TNBC cases that were retested at our institution during a 3-year period were evaluated for concordance rates in estrogen (ER) and progesterone (PR) receptor and HER2 results.

Results: We found 19 (22%) discrepancies (13 major/6 minor) among 86 cases. Minor discrepancies were in HER2 changes by immunohistochemistry, and all cases were demonstrated to be negative by and dual in situ hybridization. All major discrepancies were in ER/PR expression changes. In only 2 cases the treatment changed based on repeated results and/or patient history.

Conclusions: Discrepancies in prognostic/predictive testing continue to be frequent despite rigorous regulations. However, since for the majority of patients in our setting, the treatment plan did not change, reflex retesting for TNBC has been deemed unnecessary in our institution.

Keywords: Concordance testing; Dual in situ hybridization; Estrogen receptor; Fluorescence in situ hybridization; Human epidermal growth factor receptor 2 immunohistochemistry; In situ hybridization; Progesterone receptors; Triple-negative breast carcinoma.