Anatomy and Breast Cancer Staging: Is It Still Relevant?

Breast cancer staging concisely summarizes disease status, creating a framework for assessing and relaying prognostic information. The fundamental concepts and components of breast cancer staging are reviewed. The AJCC Cancer Staging Manual, which includes traditional anatomic factors, now includes additional tumor characteristics: tumor grade, estrogen receptor status, progesterone receptor status, human epidermal growth factor receptor 2 status, and (when available) multigene panel testing from the primary tumor. With these updates, staging provides the most reliable system for accurately predicting patient outcome. When the AJCC 8th edition guidelines are adopted, they will more closely reflect tumor biology.