Lung Cancer

Cancer and Neoplasms, Respiratory

Lung cancer is the uncontrolled cell growth in the tissues of the lung that develop into a malignant tumor. There are two main types, small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC).  Lung cancer was rare before cigarette smoking existed. Now, it is the second most common cancer in people and is the leading cause of death due to cancer in the United States (25% of all cases). In 2021, the American Cancer Society estimates that there will be about 235,760 new cases of lung cancer diagnosed in the United States. The survival rate for lung cancer is better with early diagnosis and treatment. Lung cancer usually occurs in older people and is most common in smokers and former smokers. The more and longer you have smoked, the higher the risk. After quitting smoking, the risk lowers. Lung cancer is treatable if caught early and the risk of death from lung cancer goes up if treatment is delayed.

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Lung cancer may not have any symptoms at all in the early stages. Once symptoms begin, cancer may have spread beyond the lungs. Early diagnosis and treatment are essential. If you have any of the below symptoms, see your doctor as soon as possible. These include:

  • Cough that doesn’t clear up with time or treatment
  • Wheezing
  • Recurrent infections (pneumonia, bronchitis)
  • Fatigue
  • Weakness
  • Shortness of breath
  • Blood in phlegm
  • Weight loss
  • Chest pain with breathing
  • Hoarseness

After cancer spreads, symptoms may include:

  • Swollen lymph nodes
  • Jaundice (yellow skin)
  • Headaches
  • Seizures
  • Bone pain

Lung cancer can cause a few different syndromes and the symptoms of these are:

Horner syndrome. This occurs when the cancer is at the top of the lungs. Tumors put pressure on the nerve in the upper chest and neck causing:

  • Shoulder pain
  • Drooping eyelid
  • One smaller pupil
  • No sweating on the affected side of the face

Superior vena cava syndrome. The superior vena cava (SVC) is a major vein that carries blood from the head, neck, upper chest, and arms to the heart. This syndrome is usually associated with malignancies that compress the SVC causing a blockage or impairment of the flow of blood. This compression and obstruction compromise the flow of blood back to the heart,  builds up pressure, and causes swelling in the upper chest, face, neck, and arms. A prominent sign of SVC syndrome is distended neck veins. Other symptoms include shortness of breath, dizziness, headaches, and loss of consciousness. This syndrome can be life-threatening.

Paraneoplastic syndromes. Tumors formed in lung cancer can produce hormonal substances that disrupt the hormone balance in the body. This imbalance can disrupt the anti-diuretic hormone in the kidneys causing too much salt loss in the body. It can also disrupt the adrenal glands and cause Cushing syndrome due to the overexposure of cortisol over time. Lung cancer can also raise blood calcium levels, cause blood clotting disorders and breast growth development in males.


Non-small cell lung cancer (NSCLC). Occurs in 80 to 85% of all lung cancers.  Most cases are linked with having a history of smoking. There are several subtypes of NSCLC including:

  • Adenocarcinoma – found in outer parts of the lungs
  • Squamous cell carcinoma – found near the bronchus (main airway)
  • Large cell carcinoma (undifferentiated) – can be found in any part of the lungs
  • Adenosquamous and sarcomatoid carcinoma (very rare)

Small cell lung cancer (SCLC). Occurs in 15% of all cases of lung cancer. SCLC spreads faster than non-small cell lung cancer and responds well to chemotherapy. Because it spreads so quickly, cancer usually has metastasized to surrounding tissues by the time of diagnosis.

Other types. While NSCLS and SCLC are the two main types of lung tumors found in lung cancer, other types occur. Some cancers from other organs may spread (metastasize) into the lung tissues from their original site. There are other rare types of lung tumors, including adenoid cystic carcinomas, lymphomas, sarcomas, and lung carcinoid tumors.

Risk Factors

The number one cause of lung cancer is smoking and exposure to secondhand smoke. This is the cause of 80% of deaths due to lung cancer and the biggest risk factor for getting lung cancer. However, non-smokers can also get lung cancer so other factors come into play such as:

  • Radon gas exposure
  • Secondhand smoke in the home or car
  • Pollution/smog
  • Asbestos exposure
  • Diesel exhaust
  • Changes in the DNA of cells

Also, smokers with another one of the above factors such as asbestos or radon gas exposure are at a seriously high risk of developing lung cancer.


If you have any of the above symptoms, see your doctor. They will do a thorough physical examination and most likely order the following tests:

X-rays. An x-ray can show any abnormalities or masses in the lungs.

CT scan. A CT scan is more sensitive than an x-ray and can show smaller lesions.

Sputum cytology. The doctor may take a small sample of phlegm and send it to the lab to be checked under a microscope.

Biopsy. If any of the above tests are positive, the doctor may order a lung biopsy to confirm the diagnosis.

There are new technologies that help doctors to find lung cancer early. These include:

Fluorescence bronchoscopy. The doctor inserts a bronchoscope that has a fluorescent light capable of shining light on abnormal areas unseen by normal white light.

Electromagnetic navigation bronchoscopy. This new approach to a biopsy involves using imaging followed by bronchoscopy. CT (computerized tomography) scans are taken to create a virtual bronchoscopy that reveals an abnormal area to be biopsied. Once identified, a bronchoscope with special attachments is used to biopsy hard to reach areas.

If you are diagnosed with lung cancer, the doctor will find out what stage it is at to plan treatment and care. This will involve more testing including; CT scanning, MRI, and PET Scans. These scans will check to see if the cancer is localized to the lung, growing, or spreading to other parts of the body. The stages are:

Stage I. The tumor or lesions are within the lung tissue and have not yet spread to the lymph nodes. Lesions are less than 5 centimeters in size.

Stage II. The lesion or tumor is now larger than 5 centimeters and/or growing into the chest wall, diaphragm, or pleura (lining). It may or may not have entered any lymph nodes surrounding the lungs at this time.

Stage III. By stage 3, the tumor is now outside the lung tissue and cancer cells can be found in lymph nodes outside the chest area. Lung cancer cells may be found in other organs.

Stage IV. Lung cancer cells are found far away from the lungs in distant organs, tissues, or lymph nodes.


Treatment for lung cancer largely depends on the stage the cancer is at. If it is found at a later more severe stage, the treatment needs to be more aggressive. Treatments for lung cancer are:

  • Surgery – Lobectomy, removal of the lobe of the lung; segmentectomy, removal of a wedge of the lung; pneumonectomy, removal of the entire lung
  • Radiation
  • Chemotherapy
  • Targeted Therapy – Medications that block the cancer cells growth and activity
  • Anti-Angiogenesis Therapy – Stops the production of new blood vessels that “feed” tumors

Video-assisted thoracic surgery (VATS) is now used by surgeons to treat some small lung tumors. In this procedure, the surgeon will excise parts of the lungs using small incisions. A surgeon may also have access to an instrument with robotic arms to assist in surgery.

Lung Cancer Treatment by Stage

Stage I and Stage II. When a tumor or lesion is first found at stage I or stage II in the lungs, doctors will perform surgical removal of the lesion. If there is more than one tumor or lymph node involvement chemotherapy may be used before surgery. If surgery is not possible, doctors may use radiation at these stages.

Stage III. At this stage, if cancer has spread, surgery is not recommended at first. They perform chemotherapy first to slow the growth of cancer, then radiation therapy. They can even be done at the same time, but this can have severe side-effects. If chemo and radiation are successful in shrinking tumors, the doctor may go ahead with the surgery.

Stage IV. Surgery is not usually recommended at this stage. Radiation is not usually used at this point. Doctors opt to treat this stage with aggressive doses of chemotherapy, which will not cure cancer but slow the growth to give the patient more time.

Palliative care. Palliative care is complementary care for symptoms of cancer and side-effects of treatments. These treatments include dietary adjustments, pain medications, anti-nausea medications, relaxation methods, and emotional support.

Hospice care. If cancer comes back or spreads to most of the body and the patient is given a six-month window to live, hospice may be recommended. They provide care for patients and family at the end of life. They help with pain relief, emotional support, and final arrangements.

Alternative Treatments and Home Remedies

There are no known herbal remedies that will cure lung cancer. Some complementary treatments may help with side-effects of medical treatments. These include:

Acupuncture. Needles are inserted into points on the body to help decrease pain and side-effects. Make sure you discuss this with your doctor and find a reputable practitioner.

Massage therapy. Getting a massage can help reduce anxiety levels and pain. There are some massage therapists with special training in cancer work.

Meditation. There are meditation groups that specifically deal with cancer. Meditation can help with relaxation and healing thoughts. Ask your local community hospital for any groups in your area.

Yoga. Yoga can be a gentle form of exercise for your body. It can also help stretch sore and tired muscles and increase oxygen levels in your body. Ask your doctor if this would be a good part of your treatment plan.


Smoking is the leading cause of lung cancer cases. You have resources available to you to help you to quit smoking tobacco including nicotine replacement and counseling. Education and counseling the young to help them find healthy coping mechanisms to avoid unhealthy habits like smoking are excellent preventative measures.

Lifestyle Changes

If you have been diagnosed with lung cancer, give your body what it needs to fight. The following lifestyle changes can help improve your quality of life:

Quit smoking. Quitting smoking right away reduces the factors that make cancer grow and spread. It can also help you with breathing better if your lungs are already damaged.

Manage stress. If you are overstressed your immune system will have a hard time-fighting cancer. Find ways to reduce stress in your life.

Eat healthily. Talk to your doctor about a good diet for dealing with cancer. A dietician can help you with a diet plan that gives you the right nutrients and easy to eat if you have side-effects from chemo or radiation.

Get enough rest. Your body needs all the energy it can get to fight off cancer. Pace your activities and rest when you feel tired. Don’t overdo activities or push yourself.

Create a support system. Gather people around you for support and talk about your feelings. Ask for help with household duties if you need it. Find people who will be willing to drive you to treatments and medical appointments. If you don’t have enough help, ask your doctor for community-based referrals.


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American Thoracic Society. (2014). American Journal of Respiratory and Critical Care Medicine, 189, P19-P20. Retrieved from American Thoracic Society:

Mustafa, M., Azizi, J., Ilizam, E. L. & Azizan, N. (2016, October). Lung cancer: Risk factors, management, and prognosis. IOSR Journal of Dental and Medical Sciences, 15(10), 94-101. Retrieved from:

National Cancer Institute. (2020, December 03). Non-small cell lung cancer treatment (PDQ©)-Patient version. Retrieved from National Cancer Institute:

Seligson, M. T. & Surowiec, S. M. (2020, July 13). Superior vena cava syndrome. Retrieved from StatPearls:



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