Terms & Definitions

Adjuvant Therapy: A treatment method used in addition to the main (primary) therapy. Radiation therapy often is used as an adjuvant to surgery.

Axillary Dissection: The term used to describe the operation that involves the removal of lymph nodes in the axillae (armpit). The operation is not like “picking berries.” The lymph nodes are contained in fatty tissue that surround the muscles, nerves, and blood vessels in the axillae. This tissue is removed and the pathologist finds a variable number of nodes contained in the specimen and then examines them under the microscope for evidence of spread of the tumor cells. Axillary dissection is a staging procedure that is usually performed whether the patient chooses mastectomy or breast conservation.

Benign: Sometimes there is abnormal growth of tissue that forms a mass (lump) that has no potential for spread or invasion of other tissues. These tumors are considered benign. Differentiation between benign and malignant tumors is usually made during the microscopic examination. Benign masses can cause discomfort because of their size or they can compress adjacent organs causing some problems. Benign breast tumors are usually removed for diagnosis and to eliminate them as a source of concern. They almost never turn into maliganant tumors.

Breast Conservation: This refers to breast cancer treatment that does not involve removal of the breast. This usually includes removal of the cancer with “clean margins,” axillary node sampling and radiation.

Cancer: A general term for a large number of diseases that involve cells that divide uncontrollably with the potential for spread and the breakdown of normal body function.

Cell: This is the fundamental unit that makes up the body. Cells divide and differentiate into many types that perform specific functions. Their proliferation and operation is tightly controlled so they can function in harmony with other cells.

Chemotherapy: Treatment with chemicals. Technically this would include any drug treatment but is generally accepted to refer to drug treatment of cancer. These medicines are given intravenously or orally and are systemic in that they go throughout the body. Most of these drugs are cytotoxic, meaning they kill or stop cells from dividing. They are usually potent medicines that have significant side effects.

Clean Margins: Effective breast conservation therapy requires the cancer in the breast be excised with a surrounding rim of normal breast tissue. The surgeon must balance the need to remove enough tissue around the cancerous mass against the need to avoid disfiguring the breast. The final determination of whether the margins are clean or not depends on the surgeon’s subjective evaluation at the time of surgery and the pathologist’s microscopic evaluation of the margin of the excised specimen. The pathologist’s evaluation is usually not available for 2-3 days after the operation. Sometimes margin involvement is an in-exact science. If there is any question about the margins the patient should have additional surgery to re-excise the biopsy site.

Differentiation: Soon after conception the cells of the developing fetus differentiate into muscle, bone, nerves, blood vessels, etc. until the body is formed of the many and varied tissue types. When cells mutate into cancer cells they retain a variable amount of the characteristics of the original cell. Pathologists grade the cancer as to how well it is differentiated, or in other words, how closely does it resemble the original cell type. In the case of breast cancer they follow defined criteria to categorize the tumor as well differentiated, moderately well differentiated, and poorly differentiated. They also comment on the nuclear grade which also correlates the behavior of the tumor. These classifications are important because a well differentiated cancer (or cancer with low nuclear grade) will usually be less aggressive and less likely to spread to other parts of the body. The information helps determine further treatment.

DNA: The basic molecular material that encodes the genetic information which governs the development and function of the body. Each cell contains the entire complement of DNA but only expresses that part which determines its function. Every time the cell divides the DNA must be copied (duplicated).

Excisional Biopsy: Removal of the entire lump of mass.

Genes: An amount of DNA that determines a characteristic.

Hormonal Therapy: A form of systemic therapy that usually consists of drugs that either block the effect of estrogen or block the production of estrogen. The most common drugs in use now are tamoxifen and the aromatase inhibitors.

Hot Flashes: Hot flashes have become known as the hallmark of menopause, although they are far from universal. Only about 50% of postmenopausal women have hot flashes, and only about 15% have severe flashes. Hot flashes seem to be the result of fluctuating estrogen levels and probably occur during estrogen valleys rather than peaks. They are thought to be due to reduced levels of estrogen in the hypothalamus which is in the region of the brain that regulates body temperature. Although we think of hot flashes as heat surges, they are actually the body’s attempt to cool off. Blood vessels dilate, and the heart races to pump more blood to reach the surface of the body where it’s cooler – an affect that can produce a blush or flush. Hot flashes vary dramatically from woman to woman. Some find them disabling and others claim not to mind them much.

Image Guided Biopsy: Most cancers identified with mammograms are not palpable. Ultrasound and X-rays are used to guide needle biopsies of these small lesions (see ultrasound and stereotactic biopsy).

Incisional Biopsy: Removal of a part of the mass or lump. This is rarely done anymore.

Local Control: Refers to eliminating the cancer in the breast. Mastectomy or lumpectomy and radiation are effective methods of attaining local control.

Local Recurrence: When the cancer recurs in the breast or mastectomy site. Local recurrences that are identified and treated early do not significantly change the overall prognosis.

Lumpectomy: Similar to an excisional biopsy in that the entire lump or mass is removed. A lumpectomy is usually associated with excision of a rim (~1 cm) of normal breast tissue to assure “clean margins.”

Lymphatic System: The small blood vessels in the body are designed to leak so nutrients can be delivered to the cells. That fluid is called lymphatic fluid and is carried through very delicate channels back into the chest where it is returned to the blood stream. When lymph nodes are removed these channels are disrupted and the fluid must find an alternate route back into the blood stream. If too many of the channels are obliterated they cannot return to the bloodstream. The affected extremity may become swollen when the fluid backs up (lymphedema).

Lymphedema: Swelling in an extremity (arm or leg) or breast caused by the interruption of lymphatic channels. Surgical removal of lymph nodes can cause lymphedema.

Lymph Node: The lymphatic fluid flows through collections of white blood cells called lymph nodes. They exist throughout the body but tend to congregate around larger blood vessels. The lymph nodes assist in fighting bacterial and viral infections. Metastatic cancer cells that spread through the lymphatics are often deposited in the lymph nodes.

Mastectomy: Surgical removal of the breast. Different kinds of mastectomy are listed below:

  • Radical Mastectomy: An obsolete operation that involved removal of the breast, pectoralis muscles and an extensive lymph node dissection. It was a debilitating operation that resulted in severe lymph edema in nearly 30% of the patients. It is not done anymore because controlled studies demonstrate it has no benefit over other methods of local control.
  • Modified Radical Mastectomy: Removal of the breast and some lymph nodes in the axillae. The muscles are not removed. The lymph node dissection is less extensive than the radical mastectomy and has a lower incidence of lymphedema. The local control rates of a modified radical mastectomy are as good as a radical mastectomy but with much less morbidity.
  • Total (simple) Mastectomy: Removal of the breast only. Does not include an axillary dissection. In the era of sentinal node biopsy, this is the most common type of mastectomy.
  • Subcutaneous Mastectomy: Removal of the breast with preservation of the nipple aerolar complex. A significant amount of breast tissue is left under the nipple which could be the source of a cancer in the future. It is generally thought to result in inadequate local control and therefore is not accepted as a standard treatment for breast cancer. It is sometimes used as a prophylactic operation.
  • Prophylactic Mastectomy: Removal of the breast to reduce the risk of developing breast cancer in the future. This should only be done in unusual high risk patients and then only after the patient has carefully considered her alternatives.

Metastasis: Some cancer cells have the ability to break away from the primary cancer and spread to other parts of the body. This is the most feared and deadly action of cancer cells. These cells can spread via the blood stream, the lymphatic system, or spread throughout a body cavity (abdominal cavity or pleural space in the chest). When cancer spreads to another part of the body it is still categorized by its source. A colon cancer that spreads to the liver is not “liver cancer” but colon cancer metastatic to the liver. A breast cancer that spreads to the bones is not “bone cancer” but metastatic breast cancer in the bone.

Mutation: A mutation is a mistake in the replication of the DNA. It can result in:

  • A change that is insignificant and causes no problems
  • Changes that are lethal and lead to cellular death
  • Changes in the form and function of the cell that could cause the cell to become malignant.

Needle Biopsy: Using a needle to obtain tissue for diagnosis. There are many types of needles that obtain different amounts of tissue. This is done by the surgeon or the radiologist in their office. It is sometimes used with ultrasound or X-ray guidance.

Pathologist: A medical doctor that specializes in working in the hospital laboratory. They oversee the blood testing, microbiology and perform the microscopic examination of human tissues. They are the people that examine the biopsy under the microscope and decide whether it represents a malignancy or not.

Port: A small plastic or metal container surgically placed under the skin and attached to a catheter that goes into a vein in the arm or neck. A nurse can access the port with a special needle and avoid searching for veins and “sticking” the patient many times. This simplifies the administration of chemotherapy, especially when there are few veins to place an IV.

Radiation: Energy carried by waves or a stream of particles. Types of radiation used to treat cancer include x-ray, electron beam, alpha and beta particle, and gamma ray. Radioactive substances include cobalt, radium, iridium cesium, iodine and palladium.

Radiation Oncologist: A doctor who specializes in using radiation to treat cancer.

Radiation Therapy: The use of radiation to treat cancer. The two common types of radiation therapy are:

  • External Beam Radiation: Radiation therapy that uses a machine located outside of the body to aim high-energy rays at cancer cells.
  • Brachytherapy: Internal radiation treatment achieved by implanting radioactive material directly into the tumor or close to it.

Radiologist: A doctor with special training in reading and interpreting diagnostic x-rays and performing specialized x-ray procedures.

Reconstructive Surgery: Plastic surgeons can reconstruct a breast(s) following mastectomy. There are two basics types of reconstruction and two time frames for reconstruction:

  • Implants: Silicone and saline filled implants are placed under the skin to create a breast. The operation is quite simple and the implants appear to be safe, although there is some ongoing concern about silicone implants.
  • Tissue Transfer: Skin, fat, and muscle can be transferred from the abdomen, back, or buttocks to reconstruct the breast. This is a longer and more complicated operation but generally results in a more “natural” looking breast. The reconstruction can be done at the time of mastectomy or later.
    • Immediate Reconstruction: Done at the time of mastectomy. The cancer surgeon will remove the breast and lymph nodes (as indicated) and the plastic surgeon will reconstruct the breast under the same anesthetic.
    • Delayed Reconstruction: The reconstructive surgery can be done months or years after mastectomy. If the patient needs postmastectomy radiation or needs to start chemotherapy quickly, this may be the preferred option for reconstruction.

Sentinal Lymph Nodes: As the lymphatic fluid drains out of the breast, it usually drains into 1-3 lymph nodes first. The first draining lymph nodes are the sentinal lymph nodes. If the cancer has spread to the lymph nodes, it should be in the sentinal nodes. Examining the sentinal nodes in most cases (95-100%) will result in accurate staging without removing a lot of lymph nodes and putting the patient at risk for lymphedema.

Staging: Staging is the process of categorizing an individual’s cancer in order to help determine optimal therapy and prognosis. Each type of cancer has a unique staging system that has been developed and accepted by cancer specialists throughout the country. The main elements of breast cancer staging are size of the tumor in the breast, involvement of axillary lymph nodes, and whether distant metastases are present. Statistical predictions of prognosis and treatment recommendations can then be made which are based on the Stage.

Systemic Therapy: Treatment of the entire body for the possiblity that the cancer has spread beyond the breast (see chemotherapy and hormonal therapy).

Tumor: An abnormal lump or mass of tissue. Tumors are either benign (noncancerous) or malignant (cancerous).