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What You Need To Know About™ Lung Cancer
    Posted: 07/26/2007
Diagnosis

Finding Lung Cancer Cells
Types of Lung Cancer

If you have a symptom that suggests lung cancer, your doctor must find out whether it's from cancer or something else. Your doctor may ask about your personal and family medical history. Your doctor may order blood tests, and you may have one or more of the following tests:

  • Physical exam: Your doctor checks for general signs of health, listens to your breathing, and checks for fluid in the lungs. Your doctor may feel for swollen lymph nodes and a swollen liver.

  • Chest x-ray: X-ray pictures of your chest may show tumors or abnormal fluid.

  • CT scan: Doctors often use CT scans to take pictures of tissue inside the chest. An x-ray machine linked to a computer takes several pictures. For a spiral CT scan, the CT scanner rotates around you as you lie on a table. The table passes through the center of the scanner. The pictures may show a tumor, abnormal fluid, or swollen lymph nodes.

Finding Lung Cancer Cells

The only sure way to know if lung cancer is present is for a pathologist to check samples of cells or tissue. The pathologist studies the sample under a microscope and performs other tests. There are many ways to collect samples.

Your doctor may order one or more of the following tests to collect samples:

  • Sputum cytology: Thick fluid (sputum) is coughed up from the lungs. The lab checks samples of sputum for cancer cells.

  • Thoracentesis: The doctor uses a long needle to remove fluid (pleural fluid) from the chest. The lab checks the fluid for cancer cells.

  • Bronchoscopy: The doctor inserts a thin, lighted tube (a bronchoscope) through the nose or mouth into the lung. This allows an exam of the lungs and the air passages that lead to them. The doctor may take a sample of cells with a needle, brush, or other tool. The doctor also may wash the area with water to collect cells in the water.

  • Fine-needle aspiration: The doctor uses a thin needle to remove tissue or fluid from the lung or lymph node. Sometimes the doctor uses a CT scan or other imaging method to guide the needle to a lung tumor or lymph node.

  • Thoracoscopy: The surgeon makes several small incisions in your chest and back. The surgeon looks at the lungs and nearby tissues with a thin, lighted tube. If an abnormal area is seen, a biopsy to check for cancer cells may be needed.

  • Thoracotomy: The surgeon opens the chest with a long incision. Lymph nodes and other tissue may be removed.

  • Mediastinoscopy: The surgeon makes an incision at the top of the breastbone. A thin, lighted tube is used to see inside the chest. The surgeon may take tissue and lymph node samples.

You may want to ask these questions before the doctor takes a sample of tissue:

  • Which procedure do you recommend? How will the tissue be removed?

  • Will I have to stay in the hospital? If so, for how long?

  • Will I have to do anything to prepare for it?

  • How long will it take? Will I be awake? Will it hurt?

  • Are there any risks? What is the chance that the procedure will make my lung collapse? What are the chances of infection or bleeding after the procedure?

  • How long will it take me to recover?

  • How soon will I know the results? Who will explain them to me?

  • If I do have cancer, who will talk to me about next steps? When?

Types of Lung Cancer

The pathologist checks the sputum, pleural fluid, tissue, or other samples for cancer cells. If cancer is found, the pathologist reports the type. The types of lung cancer are treated differently. The most common types are named for how the lung cancer cells look under a microscope:

  • Small cell lung cancer: About 13 percent of lung cancers are small cell lung cancers. This type tends to spread quickly.

  • Non-small cell lung cancer: Most lung cancers (about 87 percent) are non-small cell lung cancers. This type spreads more slowly than small cell lung cancer.


Glossary Terms

biopsy (BY-op-see)
The removal of cells or tissues for examination by a pathologist. The pathologist may study the tissue under a microscope or perform other tests on the cells or tissue. There are many different types of biopsy procedures. The most common types include: (1) incisional biopsy, in which only a sample of tissue is removed; (2) excisional biopsy, in which an entire lump or suspicious area is removed; and (3) needle biopsy, in which a sample of tissue or fluid is removed with a needle. When a wide needle is used, the procedure is called a core biopsy. When a thin needle is used, the procedure is called a fine-needle aspiration biopsy.
bronchoscope (BRON-koh-SKOPE)
A thin, tube-like instrument used to examine the inside of the trachea, bronchi (air passages that lead to the lungs), and lungs. A bronchoscope has a light and a lens for viewing, and may have a tool to remove tissue.
bronchoscopy (bron-KOS-koh-pee)
A procedure that uses a bronchoscope to examine the inside of the trachea, bronchi (air passages that lead to the lungs), and lungs. A bronchoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. The bronchoscope is inserted through the nose or mouth. Bronchoscopy may be used to detect cancer or to perform some treatment procedures.
fine-needle aspiration biopsy (... NEE-dul as-per-AY-shun BY-op-see)
The removal of tissue or fluid with a thin needle for examination under a microscope. Also called FNA biopsy.
incision (in-SIH-zhun)
A cut made in the body to perform surgery.
lymph node (limf node)
A rounded mass of lymphatic tissue that is surrounded by a capsule of connective tissue. Lymph nodes filter lymph (lymphatic fluid), and they store lymphocytes (white blood cells). They are located along lymphatic vessels. Also called lymph gland.
mediastinoscopy (MEE-dee-as-tih-NOS-koh-pee)
A procedure in which a mediastinoscope is used to examine the organs in the area between the lungs and nearby lymph nodes. A mediastinoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease. The mediastinoscope is inserted into the chest through an incision above the breastbone. This procedure is usually done to get a tissue sample from the lymph nodes on the right side of the chest.
non-small cell lung cancer
A group of lung cancers that are named for the kinds of cells found in the cancer and how the cells look under a microscope. The three main types of non-small cell lung cancer are squamous cell carcinoma, large cell carcinoma, and adenocarcinoma. Non-small cell lung cancer is the most common kind of lung cancer.
pathologist (puh-THAH-loh-jist)
A doctor who identifies diseases by studying cells and tissues under a microscope.
small cell lung cancer
An aggressive (fast-growing) cancer that forms in tissues of the lung and can spread to other parts of the body. The cancer cells look small and oval-shaped when looked at under a microscope.
spiral CT scan
A detailed picture of areas inside the body. The pictures are created by a computer linked to an x-ray machine that scans the body in a spiral path. Also called helical computed tomography.
sputum cytology (SPYOO-tum sy-TAH-loh-jee)
Examination under a microscope of cells found in sputum (mucus and other matter brought up from the lungs by coughing). The test checks for abnormal cells, such as lung cancer cells.
thoracentesis (THOH-ruh-sen-TEE-sis)
Removal of fluid from the pleural cavity through a needle inserted between the ribs.
thoracoscopy (THOR-uh-KOS-koh-pee)
Examination of the inside of the chest, using a thoracoscope. A thoracoscope is a thin, tube-like instrument with a light and a lens for viewing. It may also have a tool to remove tissue to be checked under a microscope for signs of disease.
thoracotomy (THOR-uh-KAH-toh-mee)
An operation to open the chest.