eBC is cancer that has not spread beyond the breast or beyond lymph nodes in the armpit. The stages of early breast cancer are stage 0, stage 1, stage 2A, stage 2B, and stage 3A.

Estrogen is a hormone that helps control sexual and reproductive health. Estrogen will bind to receptors inside cancer cells, which may cause the cells to grow.

HR- breast cancer is a cancer with cells that do not have hormone receptors. HR- cancer cells do not need hormones, like estrogen and progesterone, to grow.

HR+ breast cancer is cancer with cells that have hormone receptors. HR+ cancer cells need estrogen or progesterone to grow.

HER2- breast cancer is a type of cancer where cancer cells have no or very low levels of the HER2 protein. HER2 can cause cancer cells to grow quickly.

Lymph nodes are small, bean-shaped organs that are part of the body’s immune system. Lymph nodes filter substances and contain fluid with white blood cells that help the body fight infection and disease.

A mutation is a change in a cell’s DNA. Mutations can occur when cells divide, or by exposure to substances that can damage DNA. Some mutations can cause diseases like cancer.

The stage of a cancer describes how much cancer is in the body. It helps determine how advanced the cancer is and how best to treat it.