eBC is cancer that has not spread beyond the breast or beyond lymph nodes in the armpit. The stages of early breast cancer range from 0-3.

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.