Breast Cancer Glossary

Adjuvant treatment

Additional cancer treatment given after the primary treatment, typically surgery, to lower the risk that the cancer will come back. Adjuvant treatment may include chemotherapy, radiation therapy, hormone therapy, targeted therapy or biologic therapy.

Cancer stage

Cancer staging is the assessment of how far a person's breast cancer has progressed and influences treatment decisions and prognosis. Staging is determined based on three measures contained in your pathology report: T (Tumor Size), N (Lymph Node Status) and M (Metastasis).

CT scan

Computerized Tomography scans provide images of the body using multiple X-ray images.

Estrogen receptor-negative (ER-)

Estrogen hormone receptors not present in cancer cells.

Estrogen receptor-positive (ER+)

Estrogen hormone receptors present in some cancer cells.

HER2 negative (HER2-)

HER2 gene receptors are not present in cancer cells.

HER2 positive (HER2+)

HER2 gene receptors are present in cancer cells.

HER2 status

The HER2 gene plays an important role in cell growth and development, and your status will be characterized as HER2 positive or negative in your pathology report.

Hormone receptor status

Hormone receptor status is a positive or negative measure of estrogen (ER) or progesterone (PR) hormone receptors found in cancer cells.

Hormone receptor negative (ER and/or PR-)

In hormone receptor negative tumors, estrogen and progesterone hormone receptors are not present in cancer cells.

Hormone receptor positive (ER and/or PR+)

In hormone receptor positive tumors, estrogen and/or progesterone hormone receptors are present and may be fueling the growth of the cancer cells.

Ki67

Ki67 is a molecule that can be easily detected in growing cells in order to gain an understanding of the rate at which the cells within a tumor are actively dividing and giving rise to more cancer cells. By measuring the amount of Ki67, doctors can estimate how quickly the tumor is growing.

Lymph node status

Lymph node status measures whether or not cancer cells are present in the lymph nodes. On your pathology report, you should see T, N, M. The "N" stands for nodes and should include a number that signifies the number of nodes which contain cancer cells. If you have any nodes with cancer cells, your tumor is considered lymph node positive.

Lymph node negative

Cancer cells are not present in the lymph nodes.

Lymph node positive

Cancer cells are present in the lymph nodes.

Lymph system

Our bodies have a network of lymph nodes and lymph vessels that carry fluids throughout the body. Lymph is an almost colorless fluid that travels through lymph vessels in the lymphatic system and carries cells that help fight infection and disease. Lymph nodes are the filters along the lymph vessels that collect bacteria, viruses, cancer cells, and other unwanted substances. Breast cancer cells are frequently found in lymph nodes located in the underarm area because of their close proximity to the breast.

Metastatic status

Metastatic status refers to whether or not the cancer has spread beyond the initial site.

MRI

A type of medical imaging technology that uses magnetic fields instead of x-rays to create images of the body. MRI stands for magnetic resonance imaging.

Neoadjuvant treatment

Treatment given as a first step to shrink a tumor before the primary treatment, which is usually surgery, is given. Examples of neoadjuvant therapy include chemotherapy, radiation therapy and hormone therapy.

Pathology report

The pathology report describes the characteristics of your breast biopsy, including the tumor tissue.

Progesterone receptor-negative (PR-)

Progesterone hormone receptors not present in cancer cells.

Progesterone receptor-positive (PR+)

Progesterone hormone receptors present in some cancer cells.

Predictive tests

Predictive tests predict the likelihood that the patient will benefit from specific treatments, such as chemotherapy or hormonal treatment.

Prognostic tests

Prognostic tests measure the likelihood of a cancer to return, grow, or spread outside the primary site.

Stage 0 cancer

Noninvasive breast cancer cells.

Stage 1 cancer

Stage 1 - tumor size <2 cm, negative lymph node status, no known metastasis.

Stage 2 cancer

Stage 2 - tumor size 0-2 cm, positive lymph node status, no known metastasis OR tumor size 2-5 cm, positive or negative lymph node status, no known metastasis.

Stage 3 cancer

Stage 3 - tumor size 0-5 cm, positive lymph node status, no known metastasis OR tumor size >>5 cm with skin or chest wall involvement, positive or negative lymph node status, no known metastasis.

Stage 4 cancer

Stage 4 - any size tumor that has spread beyond the initial site and has traveled to another organ.

Tumor grade

Pathologists classify tumors into one of three grades based on how similar in appearance their cells are to normal cells, and by how many of those cells are dividing. The more cells that are dividing, the faster the tumor is likely to grow and the higher the grade. The lower the tumor grade, the better the patient's prognosis.