Here’s a glossary of medical terms related to breast cancer to help you better understand medical language:

• Adjuvant Therapy – Additional treatment given after the primary treatment (such as surgery) to lower the risk of cancer returning. It may include chemotherapy, radiation therapy, or hormone therapy.
• Alopecia – Hair loss, often a side effect of chemotherapy.
• Axillary Lymph Nodes – Lymph nodes located in the armpit that may be checked for cancer spread.
• Atypical Hyperplasia – A condition in which breast cells become abnormal but are not yet cancerous; it increases the risk of developing breast cancer.
• Benign – A non-cancerous growth that does not spread to other parts of the body.
• Biopsy – The removal of a small sample of tissue to examine under a microscope to check for cancer cells.
• BRCA1 & BRCA2 – Genes that, when mutated, increase the risk of developing breast and ovarian cancer.
• Carcinoma – A type of cancer that starts in the cells lining the organs, including the breast.
• Chemotherapy – A treatment using drugs to kill cancer cells or stop them from growing.
• Clinical Trial – A research study that tests new treatments or drugs to determine their safety and effectiveness.
• Ductal Carcinoma In Situ (DCIS) – A non-invasive form of breast cancer where abnormal cells are found in the milk ducts but have not spread.
• Dense Breast Tissue – Breast tissue that has more glandular and fibrous tissue than fatty tissue, which can make it harder to detect cancer on a mammogram.
• Estrogen Receptor (ER) Positive – A type of breast cancer that grows in response to the hormone estrogen.
• Excisional Biopsy – A procedure where the entire lump or suspicious tissue is surgically removed for examination.
• Fibroadenoma – A benign breast tumor that is firm, smooth, and movable.
• Fine Needle Aspiration (FNA) – A procedure where a thin needle is used to withdraw cells from a lump for testing.
• Genetic Testing – A test that analyzes DNA to identify mutations that may increase cancer risk.
• Grade – A classification of cancer cells based on how abnormal they look under a microscope and how fast they are likely to grow and spread. A higher grade indicates more aggressive cancer.
• HER2-Positive – A type of breast cancer that has high levels of a protein called HER2, which promotes cancer growth.
• Hormone Therapy – Treatment that blocks hormones like estrogen or progesterone to slow or stop hormone-receptor-positive breast cancer.
• Immunotherapy – A treatment that helps the immune system fight cancer.
• Invasive Ductal Carcinoma (IDC) – The most common type of breast cancer that starts in the milk ducts and spreads to surrounding tissue.
• Invasive Lobular Carcinoma (ILC) – The second most common type of breast cancer that starts in the lobules (mild producing glands) and spreads to surrounding tissue.
• Ki-67 – A protein found in cells that is used as a marker to measure how quickly cancer cells are dividing and growing. A higher Ki-67 level indicates more aggressive cancer.
• Lobular Carcinoma In Situ (LCIS) – A condition where abnormal cells are found in the lobules (milk-producing glands) of the breast. Although not considered cancer, LCIS increases the risk of developing invasive breast cancer in the future. 
• Lumpectomy – Surgery that removes only the cancerous lump and a small margin of surrounding tissue.
• Lymphedema – Swelling in the arm or chest due to fluid buildup after lymph node removal or damage.
• Mammogram – An X-ray of the breast used to detect tumors or abnormalities.
• Metastasis – The spread of cancer from the original site to other parts of the body.
• MRI (Magnetic Resonance Imaging) – A detailed imaging test used to examine breast tissue.
• Neoadjuvant Therapy – Treatment, such as chemotherapy, given before surgery to shrink a tumor.
• Needle Biopsy – A procedure that uses a thin needle to remove a tissue sample for testing.
• Oncologist – A doctor who specializes in treating cancer.
• Oncotype DX – A genomic test that analyzes the activity of certain genes in early-stage breast cancer to predict the risk of recurrence and guide treatment decisions, particularly for hormone receptor-positive breast cancer.
• Oophorectomy – Surgical removal of the ovaries, sometimes done to lower hormone levels in hormone-sensitive breast cancer.
• Pathology Report – A document that provides details about a tumor’s characteristics. This may include type, size, and hormone receptor status.
• Partial Mastectomy – Surgery that removes part of the breast, including the tumor and surrounding tissue.
• Progesterone Receptor (PR) Positive – A type of breast cancer that grows in response to the hormone progesterone.
• Radiation Therapy – A treatment that uses high-energy rays to kill cancer cells or shrink tumors.
• Reconstruction Surgery – Surgery to rebuild the breast after a mastectomy.
• Sentinel Lymph Node Biopsy – A procedure to check if cancer has spread to the lymph nodes.
• Stage – A classification system that describes how far cancer has spread.
• Survivorship – The phase of life after cancer treatment, focusing on recovery and long-term health.
• Targeted Therapy – A treatment that specifically targets cancer cells with minimal harm to normal cells.
• Triple-Negative Breast Cancer (TNBC) – A type of breast cancer that does not have estrogen, progesterone, or HER2 receptors, making it harder to treat.
• X-ray – Imaging technology sometimes used in diagnosing breast cancer.

Your Path Forward

While the information about breast cancer can feel overwhelming, you don’t have to navigate it alone. Your healthcare team is your best resource, and Outside the Doc Box is ready to help you every step of the way.  It’s okay to take one day at a time, ask questions, and seek second opinions if needed. Knowledge is power, but so is compassion—for yourself and your unique journey.

You are not defined by your diagnosis. With the right support, information, and care, you can face this challenge with strength and resilience.

At Outside the Doc Box, we offer healthcare coaching.  This is not medical advice, but are here to support you, empower you and supply you with ways to take control of your health.