Discordance of receptor status in breast cancer throughout tumor progression and the associated prognostic implications: A case report and review of the literature

Abstract

The receptor status of a breast cancer, including estrogen receptor (ER) status, progesterone receptor (PR) status, and human epidermal growth factor 2 (HER2), play a critical role in the development of a treatment plan. Typically, the primary receptor status has been used to make treatment decisions at the time of relapse, which occurs in approximately 20% of early-stage breast cancers [1]. However, multiple studies, including both prospective and retrospective, have shown that receptor status is dynamic and is unstable throughout tumor progression and during advanced stage disease [1,2,7]. National Comprehensive Cancer Network (NCCN) guidelines recommend that breast cancer patients with relapsed disease be re-biopsied secondary to the possibility of change in receptor status. Change in receptor status not only has clinical relevance when deciding on a treatment plan, it also has an impact on survival [1,2,4,7]. Of the 20% of patients that will relapse, up to one-third will have discordance between their original ER/PR receptor status and relapsed status, and up to 15% have discordance with regard to HER2 status [1]. Loss of receptor status is associated with a decrease in overall survival [1,2]. We present a case in which receptor status changed 3 times