These definitions may help you feel better informed, whether you've been diagnosed with breast cancer or know someone who has.
If you can’t find what you’re looking for here, you can call our Helpline onto talk to someone who can help.
Find out more about the topics below on our breast cancer information pages.
Ablation Removal of or stopping a part of the body from working by surgery or other means such as hormone therapy or radiotherapy.
Abraxane A type of chemotherapy drug used to treat breast cancer.
AC chemotherapy A combination of the chemotherapy drugs Adriamycin (also known as doxorubicin) and cyclophosphamide.
Adjuvant Treatment given in addition to other treatment, for example chemotherapy or radiotherapy given after surgery.
Adriamycin see Doxorubicin
Advanced breast cancer Breast cancer that has spread beyond the breast and the lymph nodes under the arm to other parts of the body. Also known as secondary, stage 4 or metastatic breast cancer.
Adverse effect An undesired or harmful effect resulting from treatment.
Alopecia Loss of hair from the head or body.
Anthracyclines A group of chemotherapy drugs commonly used to treat breast cancer. Examples include doxorubicin (also known as Adriamycin) and epirubicin.
Anti-emetics Drugs used to reduce nausea (feeling sick) or vomiting.
Areola Coloured area of skin around the nipple.
Arimidex see Anastrozole
Aromasin see Exemestane
Ascites The build-up of fluid between the two layers of the peritoneum (a membrane which forms the lining of the abdomen).
Avastin see Bevacizumab
Axilla Under the arm, the armpit.
Axillary clearance An operation to remove all the lymph nodes (also called lymph glands) from under the arm (axilla).
Axillary nodes The lymph nodes (also called lymph glands) under the arm (axilla).
Axillary sampling An operation to remove some of the lymph nodes (also called lymph glands) from under the arm (axilla).
Benign Not cancer.
Bilateral Affecting or about both the right and left sides of body. For example, a bilateral mastectomy is removal of both breasts.
Biological therapies Also known as Targeted therapies.
Biopsy Removal of tissue to be looked at under a microscope.
Bisphosphonates A group of drugs used to treat the effects of secondary breast cancer in the bone. Also given to people with primary breast cancer to prevent or treat Osteoporosis or to reduce the risk of breast cancer coming back.
Blood cells Tiny structures produced in bone marrow. Includes red blood cells, white blood cells and platelets.
Blood count The numbers of red and white blood cells and platelets in a sample of blood.
Bone marrow Spongy material found in the hollow part of the bone where red and white blood cells and platelets are produced.
Bone metastases Also known as secondary breast cancer in the bone. Cancer cells that have spread from the breast to the bones.
Bone scan A test to help identify any abnormal changes, such as tumours, infection or fractures, in the bones.
Brain metastases Also known as secondary breast cancer in the brain. Cancer cells that have spread from the breast to the brain.
BRCA1 and BRCA2 People who inherit an altered BRCA1 or BRCA2 gene from either parent have a much higher risk of developing breast cancer and some other cancers compared with the general population.
Breast calcification Areas of calcium deposit in one or both of the breasts.
Breasts Made up of lobules (milk-producing glands) and ducts (tubes that carry milk to the nipple). These are surrounded by glandular, fibrous and fatty tissue.
Breast care nurse Provides information and support to people diagnosed with breast cancer.
Breast-conserving surgery Also known as wide local excision or lumpectomy. The removal of the cancer with a margin (border) of normal breast tissue around it.
Cannula A small plastic tube through which drugs are given into a vein, usually in the arm or hand.
Carboplatin A chemotherapy drug sometimes used to treat breast cancer.
Carcinoma The medical term for cancer.
Cardiotoxicity Damage to the heart muscle causing the heart to become weaker and less efficient. May be caused by some chemotherapy and targeted therapy drugs.
Cells Tiny structures found in all living organisms.
Cell proliferation An increase in the number of cells as a result of them multiplying and growing.
Cellulitis An infection of the skin and tissue beneath the skin. People who have lymphoedema have an increased risk of cellulitis in the arm or chest area.
Chemotherapy Treatment that destroys cancer cells using anti-cancer drugs.
Chest wall Skin, muscles and bones that make up the area of the body between the neck and the abdomen.
Chronic An illness, disease or condition that is long lasting and generally slow to progress.
CISH (chromogenic in situ hybridization) A way of measuring HER2 levels in cancer cells.
Cisplatin A chemotherapy drug sometimes used to treat breast cancer.
Clinical trials Research that aims to improve treatment or care for patients.
CMF A combination of three chemotherapy drugs – cyclophosphamide, methotrexate and 5-fluorouracil (5FU).
Cognitive impairment Difficultly concentrating or being more forgetful as a result of a cancer diagnosis or treatment. Sometimes called ‘chemo brain’ or ‘chemo fog’.
Complementary therapies A varied group of therapies used alongside conventional medical treatments.
Cording (also known as axillary web syndrome) Tight ‘cords’ of tissue, stretching down the inside of the arm, which can occur after surgery to remove lymph nodes under the arm. Causes pain and restricts arm movement. Sometimes cords can be felt in the chest area too.
Core biopsy Biopsy using a hollow needle to take a sample(s) of tissue for analysis under a microscope.
CT (computerised tomography) scan Also known as a CAT scan. A type of scan that uses x-rays to take detailed pictures across the body.
CyberKnife see Stereotactic radiotherapy
Cyclophosphomide A chemotherapy drug used to treat breast cancer.
DCIS (ductal carcinoma in situ) An early type of breast cancer where the cells have not yet developed the ability to spread out of the ducts into surrounding breast tissue or to other parts of the body. Sometimes called pre-invasive, intraductal or non-invasive cancer.
Denosumab A targeted therapy used to treat the effects of secondary breast cancer in the bone.
DEXA (dual energy x-ray absorptiometry) scan A scan that measures bone density, used to assess the risk of developing, diagnosing or monitoring Osteoporosis.
Diagnostic radiographer Someone trained to carry out x-rays and scans.
DIEP (deep inferior epigastic perforator) flap A type of breast reconstruction that uses the skin and fat between the belly button and the groin.
Differentiation How different cancer cells are compared to normal cells. Well-differentiated cancer cells look almost normal (a similar size and shape to normal cells); moderately differentiated cancer cells look less like normal cells (often larger and more varied shapes); poorly differentiated cancer cells look most changed and are usually fast growing.
Drug resistance The cancer cells’ ability to resist the effects of a drug.
EGFR (epidermal growth factor receptor) Proteins on the surface of cells. When there are higher than normal levels (known as over expression) on cancer cells, they stimulate growth.
Embolism When blood flow is blocked, usually by a blood clot or air bubble.
Encapsulated Surrounded and encased. For example, an encapsulated breast implant has been encased by a build-up of dense, tough tissue, also called fibrous tissue.
Endocrine therapy see Hormone therapy
Endometrial cancer Cancer of the lining of the womb (uterus).
Epirubicin A chemotherapy drug used to treat breast cancer. One of a group of chemotherapy drugs known as anthracyclines.
Eribulin Also called Halaven. A chemotherapy drug used to treat breast cancer.
ER status ER positive (ER+) means the breast cancer has oestrogen receptors. ER negative (ER-) means the breast cancer doesn’t have oestrogen receptors (see Oestrogen receptors)
Everolimus Also known as Afinitor. A targeted therapy used to treat secondary breast cancer and given with the aromatase inhibitor exemestane.
Excision Surgical removal.
Expander implant A type of breast implant used in breast reconstruction. The implant is gradually inflated with saline (salt water) through a small port.
Faslodex see Fulvestrant
FEC A combination of the chemotherapy drugs 5-flurouracil (5FU), epirubicin and cyclophosphamide.
FEC-T A combination of the chemotherapy drugs 5-flurouracil (5FU), epirubicin, cyclophosphamide and Taxotere (docetaxel).
Femara see Letrozole
Fibrocystic A benign (not cancer) breast condition when multiple cysts or lumpy areas develop in one or both breasts.
Fine needle aspiration (FNA) Using a fine needle and syringe to take a sample of cells for analysis under a microscope.
FISH (fluorescence in situ hybridization) A way of measuring HER2 levels in cancer cells. FISH negative (FISH-) means normal levels are present, FISH positive (FISH+) means excessive amounts are present, classed as HER2+
Fluorouracil Also known as 5FU. A chemotherapy drug used to treat breast cancer.
Fraction Each radiotherapy treatment is known as a fraction. Treatment involves several fractions given over a few days or weeks.
Gamma knife see Stereotactic radiotherapy
Gemzar see Gemcitabine
Gene Stores the biological information we inherit from our parents, affecting the way we look and how our bodies work and grow.
Grade The system used to classify cancer cells according to how different they are to normal breast cells and how quickly they are growing.
Goserelin A hormone therapy drug, also known as Zoladex
HER2 (human epidermal growth factor receptor 2) A protein involved in the growth of cells. Around 15–20% of breast cancers have higher than normal levels of HER2 (known as HER2 positive) which stimulates them to grow.
Herceptin see Trastuzumab
Hereditary Characteristics, conditions or illnesses that can be passed from a parent to their child through genes.
Hickman line Also known as a skin-tunnelled catheter. A fine silicone tube through which chemotherapy drugs are given. It’s put into a large vein through a small cut in the chest wall, and can stay in place for several months.
Hormone receptor Involved in the growth of cells. In some breast cancers they bind to hormones within the cells (known as hormone receptor positive) and stimulate the cancer to grow.
Hormones Chemical messengers produced in various organs of the body that regulate growth and reproduction.
HRT (hormone replacement therapy) Female sex hormones, either oestrogen alone or a combination of oestrogen and progesterone, can help reduce menopausal symptoms.
Hypercalcaemia Higher than normal levels of calcium in the blood. Can be caused by secondary breast cancer in the bones.
Hyperplasia An increase in the number and growth of cells.
Hypocalcaemia Lower than normal levels of calcium in the blood.
Immune response An automatic defence function of the body that recognises and protects it from infection and foreign bodies, for example.
Immunosuppression Reduced ability of the body to protect against infection and disease. Can be caused by chemotherapy.
Infertility Unable to get pregnant. May be temporary or permanent and can be caused by chemotherapy, for example.
Inflammation The reaction of body tissues to injury, infection or irritation.
Inflammatory breast cancer A rare type of breast cancer where the skin of the breast looks red, and may feel warm and tender (‘inflamed’).
Infusion A method of delivering fluids or drugs, usually into a vein.
In situ (breast cancer) Breast cancer that has not developed the ability to spread outside the ducts, either within the breast or elsewhere in the body.
Intraductal see DCIS
Intramuscular (IM) An injection into the muscle.
Intravenous (IV) An injection into the vein.
Invasive cancer Has the potential to spread to other parts of the body.
Ipsilateral On the same side, as opposed to Contralateral
Kadcyla Also called trastuzumab emtansine. A targeted therapy used to treat HER2 positive breast cancer.
Ki67 A protein found in cells. The higher the levels, the faster the cells are dividing and growing.
LD (latissimus dorsi) flap A type of breast reconstruction that uses the latissimus dorsi – a large muscle in the back just below the shoulder blade along with skin and fat.
Letrozole A hormone therapy, also known as Femara. One of a group of drugs called aromatase inhibitors.
Local recurrence See Recurrence
Local treatment Specific to an area of the body, for example surgery or radiotherapy.
Locally advanced breast cancer Also known as regional recurrence. See Recurrence
Lumpectomy An operation to remove an area of breast tissue with or without a margin of healthy tissue. In breast cancer may also be called wide local excision or breast-conserving surgery.
Lymph nodes Also known as lymph glands. Small oval-shaped structures found in clusters throughout the lymphatic system, for example under the arm (axilla).
Lymphoedema Swelling of the arm, hand or breast/chest area caused by a build-up of lymph fluid in the surface tissues of the body. It can occur as a result of damage to the lymphatic system, for example because of surgery and/or radiotherapy to the lymph nodes under the arm (axilla) and surrounding area.
Lympho-vascular invasion When breast cancer cells spread into (invade) the lymph and blood vessels within the breast, and can be seen in these vessels under the microscope.
Malignant In cancer, uncontrolled growth. Invasive cells that have the potential to spread elsewhere in the body.
Mammogram A breast x-ray.
Methotrexate A chemotherapy drug used to treat breast cancer.
Mets Short for metastases.
Microcalcifications Small deposits of calcium in the breast. They show up as white dots on a mammogram, and are sometimes a sign of DCIS (ductal carcinoma in situ).
MRI (magnetic resonance imaging) scan Uses magnetism and radio waves to produce a series of images of the inside of the body. An MRI doesn’t expose the body to x-ray radiation.
Multi-centric When there is more than one area of breast cancer in different quarters (areas) of the breast.
Multi-focal When there is more than one area of breast cancer but all in the same quarter (area) of the breast.
Navelbine see Vinorelbine
Neo-adjuvant Cancer treatment, such as chemotherapy or hormone therapy, given before surgery. Sometimes called primary, for example primary hormone therapy.
Neupogen A type of GCSF
Neutropenia When the number of white blood cells falls below a certain level. May happen as a side effect of chemotherapy. If there is also a high temperature (above 38°C), it’s known as febrile neutropenia.
Occult breast cancer Breast cancer that can’t be felt or seen on imaging (for example, mammogram or ultrasound). It’s usually diagnosed when someone is being investigated for symptoms elsewhere in the body, for example enlarged lymph nodes. Sometimes a biopsy in another part of the body shows cells that look like secondary breast cancer cells, indicating there is a primary cancer in the breast, even though it can’t be seen.
Oligometastatic disease Small, isolated areas of secondary breast cancer that are stable (not progressing) and usually present in only one site of the body (oligo means ‘little' or 'few’).
Oncologist A doctor who specialises in cancer (oncology). An oncologist may be a medical oncologist (cancer drugs specialist) or clinical oncologist (radiotherapy and/or cancer drugs specialist).
Oncoplastic surgeon A breast cancer surgeon with training in plastic surgery.
OSNA (one step nucleic acid amplification) A test used during surgery to see if breast cancer cells are in the lymph nodes under the arm.
Osteopenia Decreased bone mineral density (a measurement of bone strength) but not low enough to be diagnosed as osteoporosis.
Osteoporosis Literally means 'porous bones'. Decreased bone mineral density (a measurement of bone strength), meaning thinner, weaker bones that are more likely to break. It’s usually diagnosed with a bone density scan (often called a DEXA scan).
Ovarian suppression Sometimes called ovarian ablation. Stopping the ovaries producing oestrogen using surgery or drugs.
Palliative care Focuses on symptom control and support when cancer cannot be cured. Usually involves a team of healthcare professionals such as specialist nurses, doctors, social workers and physiotherapists.
Palliative care consultant A doctor who specialises in palliative care.
Palliative care nurse A nurse who specialises in palliative care.
Palliative treatment Aims to control symptoms and slow down the progress of cancer, rather than cure it.
Pathology The branch of medicine that looks at how disease affects the body’s cells and tissues. Each time you have tissue removed a report is written by a pathologist (a doctor who examines the tissue).
Peripherally inserted central catheter (PICC) A tube put into a vein in the arm through which chemotherapy drugs are given. It stays in place throughout the course of treatment.
Perjeta See Pertuzumab.
Pertuzumab Also called Perjeta. A targeted therapy used to treat HER2 positive breast cancer.
PET (positron emission tomography) scan A scan that produces a three-dimensional image giving details on both the structure and function of organs or tissue being looked at. It is sometimes combined with a CT scan.
Plastic surgeon A specialist surgeon trained in plastic surgery techniques such as breast reconstruction.
Portacath Also called an implanted port. A thin, soft, hollow tube made of plastic that is put into a vein. The tube is attached to a rubber disc (port). Drugs are given into the port which is usually placed under the skin on the chest.
Primary breast cancer Breast cancer that has not spread beyond the breast or the lymph nodes (lymph glands) under the arm (axilla)
Progesterone receptors Proteins within cancer cells that bind to the hormone progesterone (may be abbreviated to PR).
Prognosis An estimate of the likely outlook of a disease, such as the likelihood of it coming back (recurrence) and the person’s life expectancy.
Prosthesis An artificial breast form used to restore shape when all or part of the breast has been removed.
Radiotherapy The use of high energy x-rays to destroy cancer cells.
Radiologist A doctor who specialises in the use of imaging (for example x-rays, ultrasound, CT, PET, MRI) to diagnose and treat disease.
Reconstruction Surgery that rebuilds the breast shape after all or part of the breast has been removed.
- Local recurrence Breast cancer that has come back in the chest/breast area or in the skin near the original site or scar.
- Locally advanced breast cancer (also known as regional recurrence) Breast cancer that has come back and has spread to the tissues and lymph nodes (lymph glands) around the chest, neck and under the breastbone.
- Distant recurrence Also called metastatic, advanced, stage 4 or secondary breast cancer. When cancer cells from the breast have spread to other parts of the body such as the bones, lungs, liver or brain.
Remission When the signs and symptoms of a disease partly or completely disappear. This may be temporary or permanent.
Risk factor Something that increases a person’s chance of developing an illness such as cancer.
Saline implant A type of breast implant that contains a sterile liquid solution (saline). Used in breast reconstruction.
Secondary breast cancer When cancer cells from the breast have spread to other parts of the body such as the bones, lungs, liver or brain. Also called metastases, advanced breast cancer, secondaries or stage 4 breast cancer.
Sentinel node biopsy (SNB) Identifies whether or not the first lymph node (or nodes) is clear of cancer cells.
Selective internal radiation therapy (SIRT) A type of targeted internal radiotherapy which uses radioactive beads to deliver radiation to the cancer.
Seroma A collection of fluid that forms under a wound after an operation. It is a common and sometimes uncomfortable but harmless effect of breast surgery.
SGAP (super gluteal artery perforator) flap and IGAP (inferior gluteal artery perforator) flap Types of breast reconstruction that use fat and skin taken from the upper or lower buttock.
Side effect Unwanted effect of treatments.
Silicone implant A type of breast implant filled with silicone gel. Used in breast reconstruction.
Spinal cord compression Pressure on the spinal cord and nerves. It can be caused by the cancer growing in, or spreading into, the bones of the spine and can result in permanent damage to the spinal cord.
Stable disease The cancer has stayed the same size or has grown only a little.
Stage The size of the cancer and how far it has spread.
Stereotactic core biopsy Taking a sample of tissue using a needle biopsy device connected to a mammogram machine and linked to a computer. Helps locate the exact position of the area to be biopsied.
Steroids May be given as part of cancer treatment, for example to help with side effects of chemotherapy such as nausea and vomiting or to control some symptoms caused by cancer.
Subcutaneous injection An injection into the fatty tissue under the skin.
Surgical margin How close the cancer cells are to the edges of the whole area of tissue removed during surgery.
Systemic treatment Drugs that treat the whole body, for example chemotherapy, hormone therapy or targeted therapy.
Tamoxifen A hormone therapy drug used to treat oestrogen receptor positive breast cancer.
Taxol see Paclitaxel
Taxotere see Docetaxel
TENS machine A small portable device which uses adhesive skin pads to deliver small electrical impulses to help relieve pain.
Terminal A term often used when someone is approaching the last few weeks or days of life.
Thrombosis Occurs when blood forms a clot. If the clot occurs in a major vein, the condition is known as a deep vein thrombosis or DVT.
TP53 gene A gene that provides instructions for making a protein called tumour protein p53. Some people inherit an altered TP53 gene, which can result in a rare inherited cancer syndrome called Li-Fraumeni syndrome. This can increase the risk of getting breast cancer.
TRAM (transverse rectus abdominis muscle) flap A type of breast reconstruction that uses the large muscle that runs from the lower ribs to the pelvic bone in the groin along with skin and fat.
Trastuzumab Also called Herceptin. A targeted therapy used to treat HER2 positive breast cancer, and one of a group of drugs called monoclonal antibodies.
TUG (transverse upper gracilis) flap or TMG (transverse myocutaneus gracilis) flap Types of breast reconstruction that use muscle from the inner or outer upper thigh along with skin and fat.
Tumour An overgrowth of cells forming a lump. May be benign (not cancer) or cancer.
Tumour markers Substances produced by cancer or by the body as a response to cancer.
Tyverb see Lapatinib
Ultrasound scan Uses high frequency sound waves to produce an image.
Vacuum assisted biopsy Used to remove breast tissue for examination under a microscope, often when a previous biopsy was difficult to perform or more tissue is needed to make a diagnosis. Sometimes it can be used as an alternative to surgery to remove a whole area of breast tissue (called a vacuum assisted excision biopsy).
Wide local excision (WLE) Surgery to remove breast cancer with a margin of healthy tissue. Sometimes called breast-conserving surgery or lumpectomy.
Xeloda see Capecitabine
X-ray Used to produce images of dense tissues in the body such as bone or lungs.
Zoladex see Goserelin