Lung Cancer GLOSSARY

Induction therapy:

The initial course of chemotherapy designed to induce remission.

Informed consent:

The process through which fully informed patients could participate in choices about their health care. Informed consent originates from the legal and ethical rights of patients to direct what happens to their bodies and from the ethical duty of the physician to involve the patients in their health care.

Invasive cancer:

Cancer that has spread beyond the layer of tissue in which it developed, and is growing into surrounding tissue. Also called infiltrating cancer.

Investigational drug:

A drug that has not yet been approved for commercial use in humans by the Food and Drug Administration.

Laser therapy:

The use of an intensely powerful beam of light to kill cancer cells.

Lobectomy:

Surgery that removes the lobe of the lung that contains the tumor. Lobectomy may be a surgical option available for operable non-small cell lung cancer.

Lymph nodes:

Small oval structures located throughout the lymphatic system that act as filters to keep foreign bodies from entering the bloodstream. They also produce lymphocytes, which are a component of the immune system. Also known as a lymph gland.

Malignant:

A cancer that invades nearby tissues or spreads to other parts of the body.

Mediastinum:

A mass of tissues and organs separating the two lungs. Includes the heart and its large vessels, the trachea, esophagus, thymus, lymph nodes, and other structures and tissues.

Metaplasia:

The change of adult tissue cells into an abnormal tissue.

Metastasis:

The spread of cancer from one part of the body (primary growth) to another.

Micrometastases:

The spread of cancer that is too small to be detected by routine screening tests.

Magnetic Resonance Imaging (MRI):

Magnetic Resonance Imaging (MRI) is similar to a CT scan except is uses a magnetic field instead of X-rays to create an image.

The National Lung Screening Trial:

In 2002, the National Cancer Institute, the American College of Radiology, and the American Cancer Society launched the National Lung Screening Trial. Results are expected by 2010. Interim results are periodically announced in the medical literature.

Neoadjuvant therapy:

The use of chemotherapy and/or radiation therapy prior to surgery in order to shrink tumor size and/or eradicate distant micrometastases that may cause relapse following local therapy.

Non-small cell lung cancer:

A heterogeneous group of cancers that grow and disseminate less rapidly than small cell lung cancer.

Oncology:

The field of medicine that treats cancer.

Opioid:

Synthetic chemical that has properties similar to naturally occurring opiates. Opioids, such as codeine and morphine, may be prescribed to treat pain.

Palliation:

The relief of symptoms without obtaining a cure.

Partial remission:

A response to therapy that involves tumor reduction of more than 50%.

Performance status:

Criteria used by doctors and researchers to assess how a patient's disease is progressing.

Positron Emission Tomography (PET) scan:

Positron Emission Tomography (PET) is a scan that uses a cancer's rapidly dividing cells to make a diagnosis. Radiologists give the patient a radioactive sugar substance that will be absorbed more by the cancer than by normal tissues, due to the cancer cells' increased need for energy. The PET scan records the areas where the radioactivity is focused.

Physical examination:

Physical examination is important for detecting any signs of cancer such as swollen lymph nodes in the neck or collarbone area. A physical examination is also useful for evaluating overall health.

Platelets:

A type of blood cell that helps prevent bleeding by causing blood clots to form. Also called thrombocytes.

Pleura:

The membrane that lines the inner surface of the chest wall and also covers the lungs.

Pneumonectomy:

The removal of an entire side of the lung.

Prognosis:

The likely outcome or course of a disease; the chance of recovery.

Radiation therapy:

The use of high-energy radiation from x-rays, neutrons, and other sources to kill cancer cells and shrink tumors. Radiation therapy affects cancer cells in a targeted area.

Radiation exposure:

X-rays to the chest area can increase the risk of lung cancer, especially in people who smoke.

Radon:

An odorless gas released by some soil and rocks that contain uranium. Some homes may have high levels of radon, especially on the lower levels, because they are built on soil that naturally contains radon. You can purchase Environmental Protection Agency-approved kits in hardware stores to measure the amount of radon in your home. If you find you have high levels of radon in your home, there are steps you can take that will reduce the amount of radon in your home.

Recurrence:

The return of cancer after it has been treated or removed.

Red blood cells (RBCs):

Blood cells that carry oxygen to all parts of the body. Also called erythrocytes.

Remission:

The disappearance of the signs and symptoms of cancer. Remission may be temporary or permanent.

Resection:

The surgical removal of part of an organ.

Small cell lung cancer:

A type of lung cancer characterized by aggressive rapid growth of cancer starting in the normal lung cell. Also called oat cell carcinoma, this type of lung cancer cell appears small and round when viewed under a microscope.

Secondhand smoke:

The combination of smoke from the burning end of the cigarette and from exhaled smoke. Secondhand smoke has been established as a risk factor for developing lung cancer, as well as other illnesses, such as asthma.

Series of genetic changes:

For lung cancer to develop, suppressor genes (genes that normally serve as the brakes on cellular growth), and oncogenes (genes that encourage the cell to divide), have become mutated. Unlimited growth, in the face of no mechanism to stop or slow the growth, is what fuels the cancer. Other genetic changes occur in lung cancer as well. Researchers have pinpointed changes to specific genes that contribute to the disease and hope one day to develop specific agents to act on these changes before they can snowball into a cancer. Already, some targeted therapies and chemoprevention agents have been developed that work this way.

Spiral computerized tomography (spiral CT scan):

The spiral (or helical) CT scan is a CT scan that can image the lungs in a single breath hold. CT scans use a computer to create a two-dimensional scan from a series of x-ray images. CT scans show much more detail than x-rays and the new helical or spiral scans are even more sensitive than regular CT scans.

Sputum:

The substance expelled from the lungs that contain mucus, cellular debris, microorganisms, blood, or puss.

Sputum cytology:

Phlegm coughed up from the lungs is examined under a microscope to check for abnormal or cancerous cells. (See note under Chest X-ray)

Staging:

An attempt to define the extent of a cancer in each patient based on the size of the primary tumor and the presence or absence of lymphatic involvement or metastases.

Supraclavicular lymph nodes:

Lymph nodes located in the inferior deep cervical group located between the inferior belly of the shoulder muscle and the clavicle.

Synergy:

A process in which two drugs enhance the effect of one another so that, in combination, they produce a higher response than would be expected based on their activity alone.

Systemic:

Affecting the entire body.

Targeted therapies:

Drugs that are specifically designed to interfere with the functioning or formation of cancer cells. These drugs can block specific substances involved in cancer cell growth, or they can cause cancer cells to die. A National Cancer Institute fact sheet  explains targeted therapies and how they work.

TNM:

Staging of tumors according to three basic components: primary tumor (T), lymph node status (N), and metastases (M).

Tomography:

The visualization of internal body images across a pre-determined plane of tissue.

Tuberculosis:

Tuberculosis can cause scarring, which can be a risk factor for developing lung cancer.

Tumor:

An abnormal mass of tissue that results from excessive cell division. Tumors perform no useful body function and may be either benign (not cancerous) or malignant (cancerous).

Tumor marker:

A substance sometimes found in a increased amount in the blood, other body fluids, or tissues, which may mean that a certain type of cancer is in the body. Also called a biomarker.

Trachea:

The windpipe connecting the larynx and the bronchi.

White blood cell:

A type of cell in the immune system that helps the body fight infection and disease. White blood cells include lymphocytes, granulocytes, and macrophages.