(NSCLC; Non-small Cell Lung Cancer; Non-small Cell Bronchogenic Carcinoma; Small Cell Lung Cancer)
Lung cancer – Definition
Lung cancer is a disease in which cancer cells grow in the lungs.
Cancer occurs when cells in the body divide without control or order. If cells keep dividing uncontrollably, a mass of tissue forms. This is called a growth or tumor. The term cancer refers to malignant tumors. They can invade nearby tissue and spread to other parts of the body.
There are two types of lung cancers:
- Non-small cell lung cancer — generally grows and spreads more slowly (more common form)
- Small cell lung cancer — generally grows more quickly and is more likely to spread to other parts of the body
Lung cancer – Causes
The following can cause damage to the cells in the lungs, leading to lung cancer:
- First- or second-hand smoke from cigarettes, cigars, or pipes
- Exposure to asbestos (a type of mineral) or radon (radioactive gas)
Lung cancer – Risk Factors
These factors increase your chance of developing lung cancer:
- Cigarette, cigar, or pipe smoking
- Using chewing tobacco
- Being exposed to second-hand smoke
- Being exposed to asbestos or radon
- Having a lung disease, such as tuberculosis
- Having a family or personal history of lung cancer
- Being exposed to certain air pollutants
- Being exposed to coal dust
- Radiation therapy that was used to treat other cancers
- HIV infection
Lung cancer – Symptoms
If you have any of these do not assume it is due to lung cancer. These symptoms may be caused by other conditions. Tell your doctor if you have any of these:
- A cough that doesn’t go away and worsens over time
- Constant chest pain
- Coughing up blood
- Shortness of breath, wheezing, or hoarseness
- Repeated problems with pneumonia or bronchitis
- Swelling of the neck and face
- Loss of appetite or weight loss
Lung cancer – Diagnosis
The doctor will ask about your symptoms and medical history. A physical exam will be done. The doctor will also ask about:
- Smoking history
- Exposure to environmental and occupational substances
- Family history of cancer
Tests may include:
- Chest x-ray — a test that uses radiation to take a picture of structures inside the body, especially bones
- Sputum cytology — a test that examines of a sample of mucus from the lungs
- Spiral CT — a special type of x-ray of the lungs
- Biopsy — removal of a sample of lung tissue to be tested for cancer cells. Methods include:
- Bronchoscopy — a thin, lighted tube inserted into the mouth or nose and through the windpipe to look into the breathing passages; cells or tissue samples are collected
- Needle aspiration — a needle inserted through the chest into the tumor to remove a sample of tissue
- Thoracentesis — use of a needle to remove a sample of the fluid around the lungs to check for cancer cells
- Thoracotomy — surgery to open the chest and examine lung tissue
- PET scan — an image created using a tiny amount of radiation that is put into the body
- PET/ CT scan — a type of imaging test that combines PET and CT scan (a type of x-ray that uses a computer to make pictures of the inside of the body) techniques
- Bone scintigraphy — a test that detects areas of increased or decreased bone activity
Lung cancer – Treatment
Once lung cancer is found, staging tests are done to find out if the cancer has spread. The goal of treatment is to eliminate the cancer and/or control symptoms.
Surgery involves removing the tumor and nearby tissue. Lymph nodes may also need to be removed. The type of surgery depends on the location of the tumor, such as:
- Segmental or wedge resection — removal of only a small part of the lung
- Lobectomy — removal of an entire lobe of the lung
- Pneumonectomy — removal of an entire lung
Radiation therapy is the use of radiation to kill cancer cells and shrink tumors. This may also be used to relieve symptoms, such as shortness of breath. Radiation may be:
- External — directed at the tumor from a source outside the body (more common for treating lung cancer)
- Internal — radioactive materials placed into the body in or near the cancer cells
Chemotherapy is the use of drugs to kill cancer cells. This may be given in many forms, including pill, injection, and via a catheter. Chemotherapy is often used to kill lung cancer cells that have spread to other parts of the body.
Promising New Treatments
These two types of treatments are not yet widely used. The National Cancer Institute considers these potential therapies:
- Photodynamic therapy (PDT) — a type of laser therapy. A chemical is injected into the bloodstream. It is then absorbed by the cells of the body. The chemical rapidly leaves normal cells. It will remain in cancer cells for a longer time. A laser aimed at the cancer activates the chemical. This chemical then kills the cancer cells that have absorbed it. This treatment may also be used to reduce symptoms.
- Cryosurgery — a treatment that freezes and destroys cancer tissue
If you are diagnosed with lung cancer, follow your doctor’s instructions.
Lung cancer – Prevention
To reduce your risk of getting lung cancer:
- Do not start smoking. If you smoke, quit.
- Avoid places where people are smoking.
- Test your home for radon gases and asbestos. Have these substances removed if they are in the home.
- Do not work in a place with asbestos.
The American Lung Association and American Cancer Society both suggest that screening for lung cancer with a type of CT scan may be considered if you are a smoker (or former smoker), aged 55-74 years, and have a history of heavy smoking (eg, one pack a day for 30 years).