What is Cancer?
Lung cancer is a type of cancer that begins in the lungs. Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale. Lung cancer is the leading cause of cancer deaths in the United States, among both men and women. Lung cancer claims more lives each year than colon, prostate, ovarian, lymph and breast cancers combined.

People who smoke have the greatest risk of lung cancer. The risk of lung cancer increases with the length of time and number of cigarettes smoked. If you quit smoking, even after smoking for many years, you can significantly reduce your chances of developing lung cancer.

Symptoms

Lung cancer typically does not cause signs and symptoms in its earliest stages. Signs and symptoms of lung cancer typically occur only when the disease is advanced.

Signs and symptoms of lung cancer may include:

1)A new cough that does not go away
2)Changes in a chronic cough or smokers cough
3)Coughing up blood, even a small amount
4)Shortness of breath
5)Chest pain
6)Wheezing
7)Hoarseness
8)Losing weight without trying
9)Bone pain
10)Headache

Causes

Smoking causes the majority of lung cancers -- both in smokers and in people exposed to secondhand smoke. But lung cancer also occurs in people who never smoked and in those who never had prolonged exposure to secondhand smoke. In these cases, there may be no clear cause of lung cancer. Doctors have identified factors that may increase the risk.

How smoking causes lung cancer

Doctors believe smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer-causing substances (carcinogens), changes in the lung tissue begin almost immediately. At first your body may be able to repair this damage. But with each repeated exposure, normal cells that line your lungs are increasingly damaged. Over time, the damage causes cells to act abnormally and eventually cancer may develop.

Types of lung cancer

Doctors divide lung cancer into two major types based on the appearance of lung cancer cells under the microscope. Your doctor makes treatment decisions based on which major type of lung cancer you have. The two general types of lung cancer include:

1)Small cell lung cancer. Small cell lung cancer occurs almost exclusively in heavy smokers and is less common than non-small cell lung cancer.

2)Non-small cell lung cancer. Non-small cell lung cancer is an umbrella term for several types of lung cancers that behave in a similar way. Non-small cell lung cancers include squamous cell carcinoma, adenocarcinoma and large cell carcinoma.

Western Medicine Treatment

You and your doctor choose a cancer treatment regimen based on a number of factors, such as your overall health, the type and stage of your cancer, and your preferences. Options typically include one or more treatments, including surgery, chemotherapy, radiation therapy or targeted drug therapy. In some cases you may choose not to undergo treatment. For instance, you may feel that the side effects of treatment will outweigh the potential benefits. When that is the case, your doctor may suggest comfort care to treat only the symptoms the cancer is causing, such as pain.

Treatment options for non-small cell lung cancers

Stage I - Surgery, sometimes chemotherapy
Stage II - Surgery, chemotherapy, radiation
Stage IIIA - Combined chemotherapy and radiation, sometimes surgery based on results of treatment
Stage IIIB - Chemotherapy, sometimes radiation
Stage IV - Chemotherapy, targeted drug therapy, clinical trials, supportive care

Treatment options for small cell lung cancers

1)Limited-Combined chemotherapy and radiation, sometimes surgery

2)Extensive-Chemotherapy, clinical trials, supportive care

Surgery

During surgery your surgeon works to remove the lung cancer and a margin of healthy tissue.

Procedures to remove lung cancer include:

1)Wedge resection to remove a small section of lung that contains the tumor along with a margin of healthy tissue
2)Segmental resection to remove a larger portion of lung, but not an entire lobe
3)Lobectomy to remove the entire lobe of one lung
4)Pneumonectomy to remove an entire lung

If you undergo surgery, your surgeon may also remove lymph nodes from your chest in order to check them for signs of cancer.

Lung cancer surgery carries risks, including bleeding and infection. Expect to feel short of breath after lung surgery. Your lung tissue will expand over time and make it easier to breathe. Your doctor may recommend a respiratory therapist who can guide you through breathing exercises to aid in your recovery.

Chemotherapy

Chemotherapy uses drugs to kill cancer cells. One or more chemotherapy drugs may be administered through a vein in your arm (intravenously) or taken orally. A combination of drugs usually is given in a series of treatments over a period of weeks or months, with breaks in between so that your body can recover.

Chemotherapy can be used as a first line treatment for lung cancer or as additional treatment after surgery. In some cases, chemotherapy can be used to lessen side effects of your cancer.

Radiation therapy

Radiation therapy uses high-powered energy beams, such as X-rays, to kill cancer cells. Radiation therapy can be directed at your lung cancer from outside your body (external beam radiation) or it can be put inside needles, seeds or catheters and placed inside your body near the cancer (brachytherapy). Radiation therapy can be used alone or with other lung cancer treatments. Sometimes it is administered at the same time as chemotherapy.

Targeted drug therapy

Targeted therapies are newer cancer treatments that work by targeting specific abnormalities in cancer cells. Targeted therapy options for treating lung cancer include:

1)Bevacizumab (Avastin). Bevacizumab stops a tumor from creating a new blood supply. Blood vessels that connect to tumors can supply oxygen and nutrients to the tumor, allowing it to grow. Bevacizumab is usually used in combination with chemotherapy and is approved for advanced and recurrent non-small cell lung cancer. Bevacizumab carries a risk of bleeding, blood clots and high blood pressure.

2)Erlotinib (Tarceva). Erlotinib blocks chemicals that signal the cancer cells to grow and divide. Erlotinib is approved for people with advanced and recurrent non-small cell lung cancer that have not been helped by chemotherapy. Erlotinib side effects include a skin rash and diarrhea.

Adopted From Mayo Clinic