Lung Cancer

Was this helpful?

What is lung cancer?

Lung cancer is a common cancer of the respiratory system that occurs when there is an uncontrolled growth of abnormal cells in the air passages of the lung. Lung cancer is the deadliest cancer in both men and women, according to the National Institutes of Health. The main cause of lung cancer is smoking. While not usually noticed until later in the disease, lung cancer symptoms include fatigue, chest pain, difficulty breathing, and worsening and persistent cough, which may bring up bloody sputum. Lung cancer treatment advances have improved the prognosis and survival rates for many people with this type of cancer.

Women who have never smoked may be more at risk for lung cancer than men who have never smoked. In fact, 47% of cases of lung cancer occur in women, and one in five women with lung cancer has never smoked. In contrast, only one in 10 men with lung cancer has never smoked, according to the National Lung Cancer Partnership.

As cancer progresses and metastasizes, it interferes with vital processes and functions of the lungs and o ther organs where it has spread.

Seeking regular medical care offers the best chances of discovering lung cancer in its earliest, most curable stage. If you have lung cancer, following your treatment plan may help reduce your risk of some complications of lung cancer. Lung cancer is a highly preventable cancer because the majority of cases are caused by smoking. Quitting smoking greatly reduces your risk of lung cancer. Diagnosing lung cancer in its earliest stage provides the best hope for successful treatment and a cure. If you currently smoke or have a history of smoking, talk with your doctor about testing for lung cancer.


What are the symptoms of lung cancer?

Lung cancer often produces no symptoms in its earliest stages, when it is most treatable. Symptoms may not occur for a decade or more after lung cancer has developed. When symptoms do occur, they often indicate that lung cancer has progressed to an advanced, less curable stage.

Symptoms of lung cancer include:


What causes lung cancer?

Lung cancer is a highly preventable form of cancer; the majority of cases are caused by smoking. Exposure to smoke damages the cells that line the lungs. Over time, these abnormal cells multiply and form malignant tumors, which crowd out and destroy healthy cells.

Eventually, the cancer cells can spread to other organs of the body, such as the other lung, brain, bones, adrenal glands, and liver. This is called metastatic lung cancer.

Lung cancer can be caused by:

  • Smoking, including pipes, cigarettes and cigars

  • Exposure to secondhand smoke

  • Exposure to airborne carcinogens (substances that cause cancer), such as radon and asbestos

  • Metastasis of cancer from other areas in the body, such as the breast, prostate, or bone

What are the risk factors for lung cancer?

A number of factors increase your chances of developing lung cancer. The biggest risk factor is smoking; the more you smoke and the earlier you started smoking, the greater your risk of developing lung cancer. If you smoke, quitting can greatly reduce your risk of developing lung cancer, even if you have been a heavy smoker for many years.

Not all people with risk factors will develop lung cancer, but significant risk factors for lung cancer include:

  • Smoking cigarettes, cigars or pipes

  • Exposure to carcinogens (substances that cause cancer) in the air, such as radon and asbestos

  • Exposure to secondhand smoke

  • Genetic factors tied to lung cancer. Some people inherit gene mutations that increase the risk of developing lung cancer. These mutations can increase the risk of lung cancer in both smokers and nonsmokers. It’s also possible to acquire, or develop mutations in certain genes that make cancer more likely.

Reducing your risk of lung cancer

You can significantly lower your risk of lung cancer by :

  • Not smoking

  • Avoiding exposure to carcinogens in the air (substances that cause cancer), such as radon and asbestos. Precautions include wearing an appropriate protective mask when working around carcinogens, testing your home or workplace for radon, and installing a radon mitigation system if needed.

  • Avoiding exposure to secondhand smoke


How is lung cancer treated?

Treatment of lung cancer begins with seeking regular medical care throughout your life. Regular medical care allows your doctor to evaluate symptoms, such as chronic cough, and your risks of developing lung cancer. Imaging exams and other tests can diagnose the underlying cause or help rule out lung cancer. These measures greatly increase the chances of detecting lung cancer in its earliest, most curable stage.

The goal of lung cancer treatment is to permanently cure the cancer or to bring about a complete remission of the disease. Remission means that there is no longer any sign of the disease in the body, although it may recur or relapse later. Lung cancer treatment plans use a multifaceted approach that is individualized to the type and stage of lung cancer; your age, medical history, and coexisting diseases or conditions; and other factors. The most common type of lung cancer is non-small cell lung cancer; the second-most common type is small cell lung cancer; lung carcinoid tumor is least common form of lung cancer.

Lung cancer treatment may include an individualized combination of:

  • Chemotherapy in early or late-stage lung cancer. In end-stage lung cancer, chemotherapy may be used only to help shrink the tumor to relieve symptoms

  • Dietary counseling to help people with cancer maintain their strength and nutritional status

  • Immunotherapy to improve the body’s own ability to fight off cancer cells

  • Pain medications

  • Palliative cancer care to improve the overall quality of life for families and patients with serious diseases

  • Participation in a clinical trial to test promising new therapies and treatments for lung cancer

  • Physical therapy to help strengthen the body, increase alertness, reduce fatigue, and improve functional ability during and after cancer treatment

  • Radiation therapy in early-stage or late-stage lung cancer

  • Quitting smoking to help slow or stop the growth of a lung cancer tumor

  • Supplemental oxygen

  • Surgery to remove the cancerous tumor and possibly all or part of a lung, which is generally most effective during the earliest stage of lung cancer

  • Targeted therapy to knock out factors that help cancer cells grow and multiply. Some targeted therapies are designed for specific subtypes of lung cancer. 

Complementary treatments

Some complementary treatments may help some people to better deal with lung cancer and its treatments. These treatments, sometimes referred to as alternative therapies, are used in conjunction with traditional medical treatments. Complementary treatments are not meant to substitute for traditional medical care. Be sure to notify your doctor if you are consuming nutritional supplements or homeopathic (nonprescription) remedies as they may interact with the prescribed medical therapy.

Complementary treatments may include:

  • Acupuncture
  • Massage therapy
  • Nutritional dietary supplements, herbal remedies, tea beverages, and similar products
  • Yoga

Hospice care

In cases in which lung cancer has progressed to an advanced stage and is not responding to treatment, the goal of treatment shifts away from curing the disease and focuses more on the person’s overall quality of life. The goal of hospice care is to help people in the last phases of an incurable disease live as fully and comfortably as possible. Hospice care involves medically controlling pain and other symptoms while providing psychological and spiritual support as well as services to support the patient’s family.

What are the potential complications of lung cancer?

Complications of lung cancer are life threatening. Complications are caused by an abnormally rapid growth of old or damaged cells. These cells can travel through the bloodstream and lymphatic system to other areas of the body, such as the other lung, brain, bones, adrenal glands, and liver (metastasis). Cancer cells can continue to multiply rapidly in other organs and develop new malignant tumors that interfere with normal organ function.

Over time, lung cancer can lead to serious complications including:

  • Adverse effects of anticancer treatment
  • Frequent episodes of pneumonia and bronchitis
  • Metastasis of cancer to the other lung, brain, bones, adrenal glands, and liver
  • Pleural effusion, which is an accumulation of fluid in the space around the lungs that causes difficulty breathing and shortness of breath
  • Severe bleeding from the lungs
  • Difficulty breathing

You can best treat lung cancer and lower your risk of complications, or delay the development of complications, by following the treatment plan that you and your healthcare team design specifically for you.

Was this helpful?
Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2018 Mar 8
  1. Lung Cancer. MedlinePlus, U.S. National Library of Medicine.
  2. Bope ET, Kellerman RD (Eds.) Conn’s Current Therapy. Philadelphia: Saunders, 2013.
  3. Domino FJ (Ed.) Five Minute Clinical Consult. Philadelphia: Lippincott Williams & Wilkins, 2013.
  4. Tierney LM Jr., Saint S, Whooley MA (Eds.) Current Essentials of Medicine (4th ed.). New York: McGraw-Hill, 2011.
  5. Lung Cancer. American Cancer Society.
  6. Non-Small Cell Lung Cancer. American Cancer Society.
Explore Lung Cancer
Recommended Reading
Next Up
Answers to Your Health Questions
Trending Videos