Understanding a Breast Cancer Diagnosis Hearing the words “you have breast cancer” can feel like the ground suddenly shifts beneath you. In the earliest moments after a diagnosis, most people experience a wave of emotions.shock, fear, disbelief, confusion, or even numbness. It is common for the mind to struggle to absorb what is being said. A breast cancer diagnosis is not just a medical fact; it is a life-altering moment that impacts identity, plans, and one’s sense of safety in the world.