Lung Cancer: Signs and Symptoms, Causes, Risks, Complications, Diagnosis, Treatment, Outlook and Prevention

illustration‬‏ of Lung Cancer


The lungs are probably the hardest-working organs in the body. In fact, they expand and contract for 20 times a minute just to supply oxygen to the various cells and tissues in the body.

The lungs can acquire various diseases and these can affect one’s quality of life.
One of the most serious diseases of the lungs is cancer.

This develops when the normal cells of the body evolve into cancerous ones, dividing until they form a tumor. Lung cancer is a type of cancer that starts in the lungs.

Cancer is one of the leading causes of deaths worldwide, which accounted for 8.8 million deaths in 2015. Lung cancer, for one, is the main cause of mortality in the world, with 1.69 million deaths in the same year, according to the World Health Organization (WHO).

People who smoke have the greatest risk of developing lung cancer. The risk heightens with the length of time a person had smoked and the number of cigarettes he used. Stopping smoking may significantly reduce the tendency of developing lung cancer.

2Signs and Symptoms

An estimated one-fourth of all people with lung cancer have no symptoms when the cancer is diagnosed. Most of the lung cancer cases were diagnosed via incidental chest x-rays that were intended for another reason.

However, when cancer has already progressed into stage III or stage IV, that’s when the symptoms of lung cancer appear. The symptoms include:

  • Persistent cough
  • Rusty-colored phlegm
  • Fatigue
  • Unexplained weight loss
  • Hoarseness
  • Difficulty breathing
  • Recurrent respiratory infections
  • Wheezing


Many factors and culprits cause cancer. Some people are more susceptible to developing cancer than others. In lung cancer, for instance, one of the most common cause is cigarette smoking. For example, smokers and second-hand smoke victims are more likely to develop lung cancer than those who do not smoke.

Smoking and Lung Cancer

The chemicals in cigarettes damage the cells in the lung’s lining. As a result, the chemicals may lead to the mutation lung cells into cancerous ones. Initially, the body can repair the damage these chemicals are causing. However, in time, the damage may cause the cells to grow and spread rapidly and uncontrollably, leading to cancer.

4Risk factors

Tobacco Smoke

Smoking cigarettes are the leading risk factor for lung cancer. About 80 percent of lung cancer deaths are believed to result from smoking.

Secondhand Smoke

Even if you don’t smoke, inhaling the smoke of others, called secondhand smoke, may increase the risk of developing lung cancer. In fact, about 7,000 deaths are caused by secondhand smoke-related lung cancer each year.

Radon Exposure

Radon is a radioactive gas that is associated with the development of lung cancer. In fact, it is considered the second leading cause of lung cancer.

Asbestos Exposure

People who worked with asbestos in the past such as in mines, shipyards, textile plants and places where insulation is used, are at a higher risk of dying from lung cancer. The risk is much greater for those exposed to asbestos and is smokers.

Air Pollution

In places where there are increased levels of carbon emissions like cities, the risk of lung cancer is slightly higher.


The family history of lung cancer may increase the risk of a person. This is markedly higher for immediate family members like parents, daughters, sons, and siblings.

Radiation Therapy on the Chest

Cancer patients who had radiation therapy to the chest for another cancer, may have an increased risk of developing lung cancer.


Since lung cancer affects the lungs, most of the complications are related to breathing difficulties. The complications include:

  • Coughing up blood
  • Difficulty in breathing or shortness of breath
  • Severe pain
  • Pleural effusion or fluid in the chest
  • Metastasis or cancer will spread to the various parts of the body.


Early detection and diagnosis play a crucial role in the prognosis of patients with lung and liver cancer. When the tumor is removed soon, before it began to spread to the other parts of the body, the prognosis is higher.

Just like liver cancer, there are diagnostic tests that are needed to determine if someone has lung cancer.

Imaging tests

To help diagnose lung cancer, imaging tests can be done such as x-ray, CT scan, or an MRI. These provide an image of the lungs to reveal any abnormal mass or nodule.

Sputum Cytology

Sputum cytology is helpful in determining any presence of lung cancer cells in the sputum sample of a patient.


Biopsy or getting tissue samples is necessary to determine if the removed tissue or part of the lungs has abnormal cells.

Lung Cancer Staging

The prognosis of the disease depends on the stage of cancer. Once lung cancer has been diagnosed, the doctor will need to determine the severity of the disease through a staging process.

Stage I

This stage of cancer means that the tumor hasn’t spread to the lymph nodes.

Stage II

This cancer stage means that the cancer cells have spread to surrounding structures like the pleura or lining of the lungs and diaphragm. Also, the tumor is more than 2 inches in size.

Stage III

This stage of cancer means that the cancer cells have spread to other organs near the lungs. Also, there are cancer cells in the lymph nodes.

Stage IV

This is the most advanced stage of lung cancer wherein the cancer cells have invaded other cells in other parts of the body and the lymph nodes have been affected.


After cancer has been diagnosed and staged, treatment comes next. It’s the most important phase because it determines the outcome of the patient’s health status.


Surgery (lobectomy) involves the removal of the entire lobe in which the tumor is located. This is the treatment for lung cancer in its early stages, especially if the patient is still in good health. The goal of the procedure is to eliminate all the tumor cells and prevent their spread.

There are many types of surgery associated with lung cancer:

Segmental resection

This surgery entails the removal of a larger part of the lung, but not the entire lung lobe.

Wedge resection

This means that the surgeon will remove just a small section of the lungs where the tumor is located.


This is the process of removing the entire diseased lung.


This surgical procedure means that the entire lung lobe is removed.

Radiation Therapy

Radiotherapy delivers high-energy x-rays to destroy the rapidly dividing cancer cells. It is used before surgery to shrink the tumor and after surgery to eradicate any cancer cells that remain in the area.

This procedure is also used after surgery to kill the remaining cancer cells. On the other hand, it can also be used before surgery to kill the cancer cells first, before removing the affected part.


Just like liver cancer treatment, doctors usually use chemotherapy, a combination of certain anticancer drugs to kill cancer cells.

Chemotherapy may entail just one drug or a combination of anti-cancer medicines, which are given either orally or intravenously. This procedure can also be used after surgery, to remove and kill the remaining cancer cells.

Targeted drug therapy

The targeted drug therapy is a new cancer treatment that is used to target definite abnormalities in the cancer cells. This procedure is usually used with chemotherapy drugs. These drugs should only be taken as prescribed by a licensed doctor. The drugs for targeted drug therapy include Bevacizumab (Avastin), Afatinib (Gilotrif), Ceritinib (Zykadia), Erlotinib (Tarceva), Crizotinib (Xalkori) and Nivolumab (Opdivo).


The survival rate of lung cancer depends on various factors like the type of lung cancer, the stage of cancer, chosen treatments and the general health of the patient. However, no one can accurately determine a person’s survival chances when he or she has lung cancer. The statistics are just a representation of the population through groups of people surveyed.

For lung cancer, the five-year survival rate depends on the stage of the disease. The five-year survival rate percentage means the number of people who live at least five years after being diagnosed with cancer. In some cases, the individuals live longer.

For patients with non-small cell lung cancer, the five-year survival rate is 49 percent for stage I cancer, 30 percent for stage II, 14 percent for stage III lung cancer and 1 percent for stage IV (metastatic) lung cancer.


Despite cancer’s deadly effects to the body, there are simple ways to prevent it from developing. You can prevent cancer by modifying your lifestyle by choosing healthier options and limiting cigarettes, alcohol abuse, and stress.

  • Stop smoking and drink alcohol moderately.
  • Avoid secondhand smoke.
  • Eat a healthy and balanced diet, which is more on fruits and vegetables.
  • Avoid obesity. You can do this my eating healthily and exercise regularly to maintain a healthy diet.
  • Choose vegetables and fruits over processed and junk foods.
  • Limit processed meat and other foods.
  • Be physically active. Regular exercise is important to reduce the risk of cancer and other chronic diseases.
  • Test your home for radon and asbestos, which was linked to lung cancer.
  • Avoid exposure to carcinogens at work.