Friday, November 6, 2009

Lung Cancer



Lung Cancer

Lung cancer is a disease in which uncontrolled growth of abnormal cells begins in the lungs. It is, by far, the leading cause of cancer death in the United States. The five-year survival rate for the disease is only 15 percent.

Researchers have discovered several causes of lung cancer, but the most common are related to the use of tobacco.
Causes include:
  • Cigarettes
  • Cigars and pipes
  • Environmental tobacco smoke ("secondhand smoke")
  • Radon
  • Asbestos
  • Pollution
  • Lung diseases.

Types of Lung Cancer:

Each type looks different under a microscope, grows and spreads in different ways, and is treated differently.

Non-Small Cell Lung Cancer

Non-small cell lung cancer is more common than small cell lung cancer, and it generally grows and spreads more slowly. There are three main types of non-small cell lung cancer. They are named for the type of cells in which the cancer develops:

Squamous Cell Carcinoma
Squamous cell carcinoma is a type of lung cancer that begins in squamous cells, which are thin, flat cells that look like fish scales. This form of lung cancer is also known as epidermoid carcinoma.

Adenocarcinoma
Adenocarcinoma is a form of lung cancer that begins in the cells that line the alveoli and make substances such as mucus.

Large Cell Carcinoma
Large cell carcinoma is a cancer that may begin in several types of large cells.

Other Types of Non-Small Cell Lung Cancer
Less common types of non-small cell lung cancer include:
  • Pleomorphic
  • Carcinoid tumor
  • Salivary gland carcinoma
  • Unclassified carcinoma.

Small Cell Lung Cancer

Small cell lung cancer (sometimes called oat cell cancer) is less common than non-small cell lung cancer. This lung cancertype grows more quickly and is more likely to spread to other organs in the body.
There are three types of small cell lung cancer. The types of small cell lung cancer are named for the kinds of cells found in the cancer and how the cells look when viewed under a microscope:
  • Small cell carcinoma (oat cell cancer)
  • Mixed small cell/large cell carcinoma
  • Combined small cell carcinoma.

Metastatic Cancer in the Lungs

Metastasis means the spread of cancer. Cancer cells can break away from a primary tumor and enter the bloodstream or lymphatic system (the system that produces, stores, and carries the cells that fight infections). That is how cancer cells spread to other parts of the body.
When cancer cells spread and form a new tumor in a different organ, the new tumor is a metastatic tumor. The cells in the metastatic tumor come from the original tumor. This means, for example, that if breast cancer spreads to the lungs, the metastatic tumor in the lung is made up of cancerous breast cells (not lung cells). In this case, the disease in the lungs is metastatic breast cancer (not lung cancer). Under a microscope, metastatic breast cancer cells generally look the same as the cancer cells in the breast. The lungs are one of the most common places to which cancer from other parts the body spreads.

Is Mesothelioma a Type of Lung Cancer?

Mesothelioma is not a lung cancer type. It is a tumor affecting the lining of the lungs or abdomen. Mesothelioma can either be benign (meaning not cancerous) or malignant (cancer). Exposure to asbestos particles in the air increases the risk of developing malignant mesothelioma.

Common Signs and Symptoms of Lung Cancer

Common signs and symptoms of lung cancer (when present) include:
  • A cough that doesn't go away and gets worse over time
  • Constant chest pain
  • Coughing up blood
  • Swelling of the neck and face
  • Loss of appetite
  • Fatigue
  • Fever
  • Weight loss
  • Shortness of breath, wheezing, or hoarseness
  • Repeated problems with pneumonia or bronchitis.

Other symptoms that can sometimes occur may include:
  • Changes in the shape of the fingertips
  • Swollen or enlarged lymph nodes (glands) in the upper chest and lower neck.

Things to Remember About Lung Cancer Symptoms

Symptoms of lung cancer may vary from person to person, and some patients may experience no symptoms at all. In fact, about 1 in 4 people do not have any symptoms when their disease is initially found.
The possible symptoms described above are not sure signs of lung cancer. Other health problems can also cause these symptoms. Still, a person should see their healthcare provider about any these possible lung cancer symptoms as soon as possible so that the problem can be diagnosed and treated.

Lung Cancer Diagnosis

In order to make a lung cancer diagnosis, the doctor will ask a number of questions, including questions about:
  • Current symptoms
  • Smoking history
  • Exposure to environmental and occupational substances
  • Family medical history
  • Current medications.

There are a number of tests or procedures that healthcare providers use to help diagnose lung cancer or other problems in the lungs. Some of these include:
  • Chest x-ray
  • Sputum cytology
  • Lung biopsy.

Tests Used in Staging Lung Cancer

Lung cancer staging helps the doctor plan the appropriate treatment. Some tests used to determine whether the cancer has spread include:
  • CT scan
  • MRI
  • Radionuclide scanning
  • Bone scan
  • Mediastinoscopy/mediastinotomy
  • PET scan.

Non-Small Cell Lung Cancer Stages

Stages for non-small cell lung cancer are divided into the following stages:

Occult Stage
In the occult (hidden) stage, cancer cells are found in sputum (mucus coughed up from the lungs), but no tumor can be found in the lung by imaging or bronchoscopy, or the primary tumor is too small to be assessed.

Stage 0
In stage 0 lung cancer (carcinoma in situ), cancer is limited to the lung and is found only in a few layers of cells. It has not grown through the top lining of the lung.

Stage I
In stage I lung cancer (or stage 1 lung cancer), the cancer is in the lung only, with normal tissue around the tumor. Stage I is divided into stages IA and IB, based on the size of the tumor.

Stage II
In stage II lung cancer (or stage 2 lung cancer), cancer has spread to nearby lymph nodes or to the chest wall (the ribs and muscles that make up the area of the body between the neck and the abdomen), the diaphragm (the thin muscle below the lungs and heart that separates the chest from the abdomen), the mediastinal pleura (the thin membrane that covers the outside of the lungs in the area near the heart), or the parietal pericardium (the outer layer of tissue that surrounds the heart). Stage II is divided into stage IIA and stage IIB, based on the size of the tumor and whether it has spread to the lymph nodes.

Stage III
In stage III lung cancer (or stage 3 lung cancer), cancer has either:
  • Spread to the lymph nodes in the mediastinum (the middle area between the lungs that contains the heart, major blood vessels, and other structures)
  • Spread to the lymph nodes on the opposite side of the chest or in the lower neck.
Stage III is divided into stage IIIA (which is sometimes treated with surgery) and stage IIIB (which is rarely treated with surgery).

Stage IV
In stage IV
lung cancer (or stage 4 lung cancer), cancer has spread to other parts of the body or to another lobe of the lungs.

Small Cell Lung Cancer Stages

Small cell lung cancer is divided into the following stages:

Limited-Stage
In limited-stage, cancer is found in one lung, the tissues between the lungs, and nearby lymph nodes only.

Extensive-Stage
In extensive-stage, cancer has spread outside of the lung in which it began or to other parts of the body.

Recurrent
Recurrent small cell lung cancer is cancer that has recurred (come back) after it has been treated. The cancer may come back in the chest, central nervous system, or in other parts of the body.

Treatment for Lung Cancer

There are several different lung cancer treatment options available for someone diagnosed with the disease.
Some factors that may influence recommendations regarding treatment include:
  • The type of lung cancer.
  • The stage of the cancer.
  • The patient's age and general health.

In general, treatment options for lung cancer include:
Your doctor can describe your treatment choices and the expected results of each. You and your doctor can work together to develop a treatment plan that meets your medical needs and personal values. Choosing the most appropriate treatment for lung cancer is a decision that ideally involves the patient, family, and healthcare team.
Treatment generally begins within a few weeks after the diagnosis. In most cases, there will be time for patients to talk with the doctor about treatment choices, get a second opinion, and learn more about the disease.

Lung Cancer Treatment Providers

There are usually several healthcare providers involved in a person's treatment. The doctor may refer patients to doctors who specialize in treating lung cancer, or patients may ask for a referral. Some specialists who treat lung cancer include:
  • Pulmonologists, who are doctors that are experts in diseases of the lungs
  • Surgeons, who are doctors that perform operations
  • Medical oncologists, who are doctors that are experts in lung cancer and treat cancers with medicines
  • Radiation oncologists, who are doctors that treat lung cancers with radiation.

Non-Small Cell Lung Cancer Treatment by Stage:


Non-Small Cell Lung Cancer Treatment at Stage 0

Treatment of stage 0 non-small cell lung cancer (carcinoma in situ) may include the following:
  • Surgery to remove a small portion of the lung where the cancer cells are found.

Non-Small Cell Lung Cancer Treatment at Stage I

Treatment of stage I non-small cell lung cancer may include the following:
  • Lung cancer surgery to remove a small portion of the lung or a lobe of the lung
  • External radiation therapy (for patients who cannot have surgery or choose not to have surgery)
  • Lung cancer chemotherapy following surgery.


Non-Small Cell Lung Cancer Treatment at Stage II

Treatment of stage II non-small cell lung cancer may include the following:
  • Surgery to remove the tumor (a small portion of the lung, a lobe of the lung, or an entire lung)
  • External lung cancer radiation therapy (for patients who cannot have surgery or choose not to have surgery)
  • Chemotherapy with or without other treatments following surgery.

Non-Small Cell Lung Cancer Treatment at Stage III

Stage III of non-small cell lung cancer is divided into two subgroups: stage IIIA and stage IIIB.
Treatment of stage IIIA non-small cell lung cancer may include the following:
  • Lung cancer surgery alone
  • External radiation therapy alone
  • Chemotherapy combined with other treatments
  • Surgery and external radiation therapy.
Treatment of stage IIIB non-small cell lung cancer may include the following:
  • External radiation therapy alone
  • Chemotherapy combined with external radiation therapy
  • Chemotherapy combined with external radiation therapy, followed by surgery
  • Chemotherapy alone.

Non-Small Cell Lung Cancer Treatment at Stage IV

Treatment of stage IV non-small cell lung cancer may include the following:
  • External radiation therapy as palliative therapy, to relieve pain and other lung cancer symptoms and improve the quality of life
  • Chemotherapy
  • Laser therapy and/or internal radiation therapy.

Treatment of Recurrent Non-Small Cell Lung Cancer

Treatment of recurrent non-small cell lung cancer may include the following:
  • External radiation therapy as palliative therapy, to relieve pain and other symptoms and improve the quality of life
  • Chemotherapy alone
  • Surgery (for some patients who have a very small amount of cancer that has spread to the brain)
  • Laser therapy or internal radiation therapy
  • Radiosurgery (for certain patients who cannot have standard surgery).

Small Cell Lung Cancer Treatment by Stage:


Limited-Stage
Treatment of limited-stage small cell lung cancer may include the following:
  • Combination small cell lung cancer chemotherapy and radiation therapy to the chest, with or without radiation therapy to the brain
  • Combination chemotherapy with or without small cell lung cancer radiation therapy to the brain in patients with complete response (patients with no visible signs of cancer after initial chemotherapy)
  • Combination lung cancer chemotherapy with or without radiation therapy to the chest
  • Lung cancer surgery followed by chemotherapy, or chemotherapy plus radiation therapy to the chest -- with or without radiation therapy to the brain.

Extensive-Stage
Treatment of extensive-stage small cell lung cancer may include the following:
  • Chemotherapy
  • Combination chemotherapy
  • Combination chemotherapy with or without radiation therapy to the brain for patients with complete response
  • Radiation therapy to the brain, spine, bone, or other parts of the body where the cancer has spread, as palliative therapy to relieve symptoms and improve quality of life.

Recurrent
Treatment of recurrent small cell lung cancer may include the following:
  • Radiation therapy as palliative therapy to relieve symptoms of small cell lung cancer and improve quality of life
  • Chemotherapy as palliative therapy to relieve symptoms and improve quality of life.
  • Laser therapy, surgical placement of devices to keep the airways open, and/or internal radiation therapy, as palliative therapy to relieve symptoms and improve quality of life.

Preventing Lung Cancer: Know the Risk Factors

The first step in the prevention of lung cancer is knowing the risk factors. Researchers have identified the following lung cancer risk factors:
  • Smoking
  • Second-hand smoke
  • Environmental causes
  • Beta-carotene in smokers.

Smoking
By far the largest risk factor for lung cancer is smoking. Studies show that smoking tobacco products in any form is the major cause of lung cancer. People who stop smoking and never start again lower their risk of developing lung cancer or of having lung cancer come back.
Many products are available to help people trying to quit smoking, including:
  • Nicotine gum
  • Nicotine sprays
  • Nicotine inhalers
  • Nicotine patches
  • Nicotine lozenges
  • Antidepressant drugs.

Second-Hand Smoke
Second-hand tobacco smoke also causes lung cancer. This is smoke that comes from a burning cigarette or other tobacco product, or smoke that is exhaled by smokers. People who inhale second-hand smoke are exposed to the same cancer-causing agents as smokers, although in weaker amounts. Inhaling second-hand smoke is called involuntary or passive smoking.

Environmental Causes
There are other causes of lung cancer in the environment, but their effect on lung cancer rates is small compared to the effect of cigarette smoking. Cancer-causing agents that may be found indoors, especially in the workplace, include:

These substances can cause lung cancer in people who have never smoked, and combine with cigarette smoke to further increase lung cancer risk in smokers. Many countries are working to control these cancer-causing agents in the workplace.

Air pollution may also increase the risk of lung cancer. Studies show that lung cancer rates are higher in cities with higher levels of air pollution.
Beta Carotene
Lung cancer research studies show that beta carotene use in relatively high-intensity smokers increases the risk of lung cancer.

Are There Protective Options to Help Prevent Lung Cancer?

Studies show that a diet rich in fruit, and possibly vegetables, may help lower the risk of lung cancer, while excessive alcohol consumption may increase the risk of lung cancer. In addition, studies show that people who are physically active may have a lower risk of lung cancer than those who are not, even after taking cigarette smoking into account. Taking vitamin E supplements does not reduce the risk of developing lung cancer.

Lung Cancer Research

Some of the current research on lung cancer includes work being done to study the effectiveness of using new drugs, new combinations of chemotherapy, and combinations of chemotherapy and radiation therapy before and after surgery to treat the disease. Research is also being conducted to investigate the effectiveness of using biological therapy to treat lung cancer.








No comments:

Post a Comment

^ Scroll to Top