Definition of lung cancer: Cancer that forms in tissues of the lung, usually in the cells lining air passages. The two main types are small cell lung cancer and non-small cell lung cancer. These types are diagnosed based on how the cells look under a microscope.
Estimated new cases of lung cancer (non-small cell and small cell combined) in the United States in 2016: 224,390
Lung cancer is the second most common cancer and the primary cause of cancer-related death in both men and women in the United States. Incidence rates are highest among African American men, followed by white men.
Although smoking is the main cause of lung cancer, lung cancer risk also is increased by exposure tosecondhand smoke; environmental exposures, such as radon, workplace toxins (e.g., asbestos,arsenic), and air pollution. The risk of lung cancer can be reduced by quitting smoking and by eliminating or reducing exposure to secondhand smoke and environmental and workplace risk factors. The National Lung Screening Trial has shown that screening current or former heavy smokers with low-dose helical computed tomography (CT) decreases their risk of dying from lung cancer. Standard treatments for lung cancer include surgery, radiation therapy, chemotherapy, immunotherapy, targeted therapy, laser therapy, photodynamic therapy, cryosurgery, endoscopic stent placement, and electrocautery.
The following stages are used for non-small cell lung cancer:
Occult (Hidden) Stage
In the occult (hidden) stage, cancer cannot be seen by imaging or bronchoscopy. Cancer cellsare found in sputum (mucus coughed up from the lungs) or bronchial washing (a sample of cells taken from inside the airways that lead to the lung). Cancer may have spread to other parts of the body.
Stage 0 (Carcinoma In Situ)
In stage 0, abnormal cells are found in the lining of the airways. These abnormal cells may becomecancer and spread into nearby normal tissue. Stage 0 is also called carcinoma in situ.
Stage I
In stage I, cancer has formed. Stage I is divided into stages IA and IB:
- Stage IA: The tumor is in the lung only and is 3 centimeters or smaller.
- Stage IB: Cancer has not spread to the lymph nodes and one or more of the following is true:
- The tumor is larger than 3 centimeters but not larger than 5 centimeters.
- Cancer has spread to the main bronchus and is at least 2 centimeters below where thetrachea joins the bronchus.
- Cancer has spread to the innermost layer of the membrane that covers the lung.
- Part of the lung has collapsed or developed pneumonitis (inflammation of the lung) in the area where the trachea joins the bronchus.
Stage II
Stage II is divided into stages IIA and IIB. Stage IIA and IIB are each divided into two sections depending on the size of the tumor, where the tumor is found, and whether there is cancer in thelymph nodes.
(1) Cancer has spread to lymph nodes on the same side of the chest as the tumor. The lymph nodes with cancer are within the lung or near the bronchus. Also, one or more of the following is true:
-
- The tumor is not larger than 5 centimeters.
- Cancer has spread to the main bronchus and is at least 2 centimeters below where thetrachea joins the bronchus.
- Cancer has spread to the innermost layer of the membrane that covers the lung.
- Part of the lung has collapsed or developed pneumonitis (inflammation of the lung) in the area where the trachea joins the bronchus.
or
(2) Cancer has not spread to lymph nodes and one or more of the following is true:
-
- The tumor is larger than 5 centimeters but not larger than 7 centimeters.
- Cancer has spread to the main bronchus and is at least 2 centimeters below where the trachea joins the bronchus.
- Cancer has spread to the innermost layer of the membrane that covers the lung.
- Part of the lung has collapsed or developed pneumonitis (inflammation of the lung) in the area where the trachea joins the bronchus.
- Stage IIB:
(1) Cancer has spread to nearby lymph nodes on the same side of the chest as the tumor. The lymph nodes with cancer are within the lung or near the bronchus. Also, one or more of the following is true:
-
- The tumor is larger than 5 centimeters but not larger than 7 centimeters.
- Cancer has spread to the main bronchus and is at least 2 centimeters below where thetrachea joins the bronchus.
- Cancer has spread to the innermost layer of the membrane that covers the lung.
- Part of the lung has collapsed or developed pneumonitis (inflammation of the lung) in the area where the trachea joins the bronchus.
or
(2) Cancer has not spread to lymph nodes and one or more of the following is true:
-
- The tumor is larger than 7 centimeters.
- Cancer has spread to the main bronchus (and is less than 2 centimeters below where the trachea joins the bronchus), the chest wall, the diaphragm, or the nerve that controls the diaphragm.
- Cancer has spread to the membrane around the heart or lining the chest wall.
- The whole lung has collapsed or developed pneumonitis (inflammation of the lung).
- There are one or more separate tumors in the same lobe of the lung.
Stage IIIA
Stage IIIA is divided into three sections depending on the size of the tumor, where the tumor is found, and which lymph nodes have cancer (if any).
(1) Cancer has spread to lymph nodes on the same side of the chest as the tumor. The lymph nodes with cancer are near the sternum (chest bone) or where the bronchus enters the lung. Also:
- The tumor may be any size.
- Part of the lung (where the trachea joins the bronchus) or the whole lung may have collapsed or developed pneumonitis (inflammation of the lung).
- There may be one or more separate tumors in the same lobe of the lung.
- Cancer may have spread to any of the following:
- Main bronchus, but not the area where the trachea joins the bronchus.
- Chest wall.
- Diaphragm and the nerve that controls it.
- Membrane around the lung or lining the chest wall.
- Membrane around the heart.
or
(2) Cancer has spread to lymph nodes on the same side of the chest as the tumor. The lymph nodes with cancer are within the lung or near the bronchus. Also:
- The tumor may be any size.
- The whole lung may have collapsed or developed pneumonitis (inflammation of the lung).
- There may be one or more separate tumors in any of the lobes of the lung with cancer.
- Cancer may have spread to any of the following:
- Main bronchus, but not the area where the trachea joins the bronchus.
- Chest wall.
- Diaphragm and the nerve that controls it.
- Membrane around the lung or lining the chest wall.
- Heart or the membrane around it.
- Major blood vessels that lead to or from the heart.
- Trachea.
- Esophagus.
- Nerve that controls the larynx (voice box).
- Sternum (chest bone) or backbone.
- Carina (where the trachea joins the bronchi).
or
(3) Cancer has not spread to the lymph nodes and the tumor may be any size. Cancer has spread to any of the following:
- Heart.
- Major blood vessels that lead to or from the heart.
- Trachea.
- Esophagus.
- Nerve that controls the larynx (voice box).
- Sternum (chest bone) or backbone.
- Carina (where the trachea joins the bronchi).
Stage IIIB
Stage IIIB is divided into two sections depending on the size of the tumor, where the tumor is found, and which lymph nodes have cancer.
(1) Cancer has spread to lymph nodes above the collarbone or to lymph nodes on the opposite side of the chest as the tumor. Also:
- The tumor may be any size.
- Part of the lung (where the trachea joins the bronchus) or the whole lung may have collapsed or developed pneumonitis (inflammation of the lung).
- There may be one or more separate tumors in any of the lobes of the lung with cancer.
- Cancer may have spread to any of the following:
- Main bronchus.
- Chest wall.
- Diaphragm and the nerve that controls it.
- Membrane around the lung or lining the chest wall.
- Heart or the membrane around it.
- Major blood vessels that lead to or from the heart.
- Trachea.
- Esophagus.
- Nerve that controls the larynx (voice box).
- Sternum (chest bone) or backbone.
- Carina (where the trachea joins the bronchi).
or
(2) Cancer has spread to lymph nodes on the same side of the chest as the tumor. The lymph nodes with cancer are near the sternum (chest bone) or where the bronchus enters the lung. Also:
- The tumor may be any size.
- There may be separate tumors in different lobes of the same lung.
- Cancer has spread to any of the following:
- Heart.
- Major blood vessels that lead to or from the heart.
- Trachea.
- Esophagus.
- Nerve that controls the larynx (voice box).
- Sternum (chest bone) or backbone.
- Carina (where the trachea joins the bronchi).
Stage IV
In stage IV, the tumor may be any size and cancer may have spread to lymph nodes. One or more of the following is true:
- There are one or more tumors in both lungs.
- Cancer is found in fluid around the lungs or the heart.
- Cancer has spread to other parts of the body, such as the brain, liver, adrenal glands,kidneys, or bone.
The following stages are used for small cell lung cancer:
Limited-Stage Small Cell Lung Cancer
In limited-stage, cancer is in the lung where it started and may have spread to the area between the lungs or to the lymph nodes above the collarbone.
Extensive-Stage Small Cell Lung Cancer
In extensive-stage, cancer has spread beyond the lung or the area between the lungs or the lymph nodes above the collarbone to other places in the body.
All information was taken from the NCI (National Cancer Institute)
