What to know about lung cancer

What to know about lung cancer

Lung cancer is a condition that causes uncontrollable division of cells in the lungs. This causes tumor growth which decreases a person’s breathing ability.

In 2015 218,527 people in the United States were diagnosed with lung cancer, according to the Centers for Disease Control. Early diagnosis in the course of the disease may help a person obtain treatment as early as possible.

However, it can be difficult to identify lung cancer in its earliest stages, because the symptoms may be similar to those of a respiratory infection or there may be no symptoms at all.

We explain the nature of lung cancer in this article, how to recognize the symptoms and how doctors treat lung cancer before it becomes life-threatening.

What is lung cancer?

Lung cancer causes mutations in cells.
Lung cancer causes mutations in cells.

Cancer causes certain mutations in cells which are otherwise healthy.

The body usually programs cells to die to prevent overgrowth at a certain point in their life cycle. Cancer overrides this instruction, which causes cells to grow and multiply when not supposed to.

Overgrowth of the cells leads to tumor development and cancer’s harmful effects.

In lung cancer, this cell overgrowth pattern occurs in the lungs which are vital organs for breathing and exchanging oxygen.

Doctors usually identify two forms of lung cancer, small and non-small cells, based on how microscopically they look. An individual has a greater risk of developing non-small cell lung cancer than small cells.

Although anyone may develop lung cancer, cigarette smoking and smoke exposure can increase a person’s likelihood of developing the condition. A person with a history of exposure to inhaled chemicals or other toxins can develop lung cancer.

Even if this exposure to chemicals and other contaminants was long ago, it can cause cancer-causing changes in lung cells.


Symptoms do not always occur in people with lung cancer until the condition has reached a later stage.

Some people, however, may notice symptoms that they may think are related to a less serious, acute disease.

Examples of these symptoms include:

  • appetite loss
  • changes to a person’s voice, such as hoarseness
  • frequent chest infections, such as bronchitis or pneumonia
  • lingering cough that may start to get worse
  • shortness of breath
  • unexplained headaches
  • weight loss
  • wheezing

An individual may also experience more serious lung cancer-related symptoms. These include severe pain to the chest or bone, or blood coughing.


If a doctor detects a suspected lesion on a scan for lung cancer, or a person has symptoms that may suggest lung cancer, there are several diagnostic tests available to validate the next steps.

Examples of these include:

Imaging studies: Computed tomography ( CT) and positron emission tomography ( PET) scans might reveal areas of lung tissue with cancer. Bone scans may also show cancerous growths. Doctors may also use these scans to track treatment progress or after a course of treatment to ensure that cancer has not returned.

Imaging can help display a lung tumor or track the progress of treatment.
Imaging can help display a lung tumor or track the progress of treatment.

Tissue sampling: If a doctor in an imaging study identifies a suspicious lesion, they may recommend taking a sample of lung tissue to test for potentially cancerous cells.

There are various methods to take a sample of tissue and sometimes the process depends on the location of the lesion.

Another example is when a doctor performs a bronchoscopy with a camera at the top, which requires installing a special thin, lighted scope. It lets the doctor see the lesion and then get samples.

Less accessible lung lesions can require more invasive surgery to remove lung tissue, such as thoracoscopy or video-assisted thoracic surgery.

Laboratory testing: A physician can may prescribe sputum tests or blood tests to check for lung cancer.

A doctor can use this knowledge to assess what type of lung cancer can develop and whether the disease has become advanced.

The importance of early diagnosis

Life-saving may be the early diagnosis of lung cancer. That is because the lung cancer cells will migrate to other parts of the body before being identified in the lungs by a doctor. When this spread or metastasis has happened it will make it much more difficult to treat the disease.

A doctor will often recommend that a person get tested for lung cancer. These are accomplished using a low dose CT scanner. Not everyone is a candidate for this test but in certain individuals it will help doctors detect lung cancer earlier.

Individuals who may be eligible for lung cancer screenings are, according to the American Lung Association, the ones who:

  • are between 55 and 80 years of age
  • are a 30 pack-year history of smoking, meaning they smoked one pack per day for 30 years or two packs per day for 15 years
  • are a current smoker or smoker who has quit within the past 15 years

If a person meets all those criteria, insurance will often cover this screening. People can also also consult with their insurance provider before signing up for screening for lung cancer.


The cancer stage shows how far and extent it has spread through the body. The classification helps doctors endorse the best outcomes and guide the treatment.

Every stage determines whether or not cancer has spread, or is spreading, to nearby lymph nodes. It may also consider the number and size of the tumors.

The lymph nodes are part of the lymphatic system, which connects to the rest of the body. When cancer enters these, it may become more risky to metastasize, or further spread.

Staging for lung cancer within each stage is highly complex and detailed, with many subgroups.

Clinicians initially divide it up into classifications of small cells and non-small cells.

Staging definitions can vary but doctors usually use the tumor size and spread to direct non-small cell lung cancer in the following way:

  • Occult, or hidden: Cancer does not show on imaging scans, but cancerous cells might appear in the phlegm or mucus and may have reached other parts of the body.
  • Stage 0: The doctor finds abnormal cells only in the top layers of cells lining the airways.
  • Stage I: A tumor has developed in the lung, but is under 5 centimeters (cm) and has not spread to other parts of the body.
  • Stage II: The tumor is smaller than 5 cm and might have spread to the lymph nodes in the area of the lung, or smaller than 7 cm and spread to nearby tissues but not lymph nodes.
  • Stage III: Cancer has spread to the lymph nodes and reached other parts of the lung and surrounding area.
  • Stage IV: Cancer has spread to distant body parts, such as the bones or brain.

Small cell lung cancer has its own limited and extensive categories, in reference to whether cancer has spread inside or outside the lungs.


Lung cancer treatments depend on the location and stage of the treatment, as well as individual overall health.

Surgery and radiation are the most common approaches to lung cancer treatment but there are other treatments available. For example , doctors often take chemotherapy to treat small cell lung cancer.

Possible therapies include:

Surgery: A doctor can operate in nearby areas where cancer may have spread to remove cancerous lung tissue and tissue. This often involves removing a lobe or large lung section in a procedure known as lobectomy.

In extreme cases, the surgeon can extract a whole lung. An individual can live without a lung, but after lung removal, being in good health before surgery helps improve outcomes.

Chemotherapy: Drugs used for this procedure are used to shrink or kill cancer cells. These medications tend to separate cells rapidly, making them suitable for cancer treatment.

Treatment with chemotherapy has a greater effect on cancers that have spread to different parts of the body and need a body-wide attack.

Chemotherapy, however, is a strong technique which can have side effects that include severe nausea which weight loss.

Radiation therapy: This technique takes advantage of high-energy radiation to destroy cancer cells. A doctor may may use radiation to shrink a tumor until it is surgically removed.

Radiation therapy is useful primarily for cancers that occur at one location and have not spread.

Targeted therapy: This is the use of specific medications specifically targeting a specific behavior in cancer cells. Examples include medicines which stop the multiplication of cancer cells.

In certain countries, diagnosis of lung cancer also involves the collaboration of medical experts. Those experts may include:

  • surgeons
  • radiation oncologists
  • specialists in lung treatment called pulmonologists
  • pulmonary therapists


A lady smoking
Smoking is the number one cause of lung cancer, and quitting is a great way to reduce the risk.

According to the American Cancer Society, lung cancer is the number one cause of death from cancer. An estimated 154,050 individuals are predicted to die in 2018 from lung cancer.

The condition brings a greater risk of death compared to combined breast , colon and prostate cancer. By not smoking it’s also entirely preventable. When diagnosed in its early stages, lung cancer is more treatable.

The outlook and prognosis for lung cancer depends on the type of cancer and the spread. People should speak to their doctor who can provide a more accurate prognosis taking into account the general health of the patient and the severity of their cancer.


Lung cancer is a serious and potentially deadly disease which affects the breathing capacity of a person.

Early diagnostic screening of people at high risk for lung cancer, however, can help them receive treatment in earlier and more treatable stages. The size and spread of cancer is what decides the outlook for patients.

Treatment options include surgery to remove portions or more of the lung tissue, chemotherapy and radiation therapy, as well as targeted drug treatment.

If anyone has concerns that they may be at risk for lung cancer, they will talk with their doctor.


What is the best way to prevent lung cancer?


The best way to prevent lung cancer is not to smoke cigarettes or to quit smoking if you are a smoker.

Answers represent our medical experts’ opinions. All material is purely informational and medical advice should not be considered.