What does lung cancer look like?
The likelihood of living for at least 5 years after a diagnosis of lung cancer depends on its type and the stage at diagnosis.
For example, if small cell lung cancer is limited to a single tumor in the lung, the likelihood of living for 5 years or more is 31%. This figure reduces to 2% after the cancer has spread to distant parts of the body.
If non-small cell lung cancer has not spread beyond the lungs, a person has a 60% likelihood of living for least 5 years after the diagnosis. This figure falls to 6% after the cancer reaches a later stage, according to the American Society of Clinical Oncology (ASCO).
A range of tools can help diagnose lung cancer, including lung imaging scans. The scans can show the location and severity of the cancer and may even indicate its type.
Diagnosing lung cancer is challenging, even for healthcare professionals. Comparing images online can give a person an incorrect impression. It is important to consult a doctor.
Here are some characteristics of various types of lung cancer:
Small cell lung cancer
A chest X-ray showing a lung cancer tumor.
Small cell lung cancer, also called oat cell cancer, accounts for around 13% of lung cancer cases.
This type tends to spread to other areas of the body more quickly than other types of lung cancer, and the tumors grow rapidly.
In most cases, small cell lung cancer tumors develop toward the center of the lungs. They also extend outward from the lobar bronchi, divisions of the lung's main airways.
On a chest X-ray, these tumors may appear as white masses located toward the center of the lungs.
Non-small cell lung cancer
There are several types of non-small cell lung cancer. Each shows up differently on lung scans.
Non-small cell lung cancers can still be difficult to distinguish, however, particularly on chest X-rays.
Find out more about small cell and non-small cell lung cancers.
Adenocarcinoma accounts for about 40% of lung cancers. This type starts in the outer portions of the lungs and grows slowly.
On a lung scan, adenocarcinoma can resemble small cell lung cancer, but it forms on the outer parts of the lungs, rather than near the center.
Adenocarcinoma develops as round nodules in the lungs, and these first appear in cells that produce mucus.
There are several types of adenocarcinoma, and diagnosing the specific type is important because it can affect the treatment and outlook.
Smoking is the main risk factor for adenocarcinoma, but it is also the type of lung cancer that most frequently develops in nonsmokers.
Squamous cell (epidermoid) carcinoma
Image credit: Yale Rosen, Apr. 13, 2011.
The tumors usually appear near one of the lung's main airways. As the tumors grow, they may extend into the wall of the chest.
Large cell (undifferentiated) carcinoma
This type of carcinoma accounts for 10–15% of all lung cancer cases.
Large cell (undifferentiated) carcinoma can appear anywhere in the lungs.
Because it grows and spreads quickly, it may extend outside of the lung.
It is one of the most difficult forms of lung cancer to treat.
A layer of cells called the mesothelium surrounds the lungs, heart, abdomen, and other organs. The pleura, a type of mesothelium, surrounds the lungs.
Pleural mesothelioma, usually just called mesothelioma, is cancer that first develops in this layer of tissue.
According to the American Cancer Society (ACS), a chest X-ray may reveal:
- a thickening of the pleura
- calcium deposits on the pleura
- fluid between the lungs and the chest wall
- other changes in the lungs that can suggest mesothelioma
Here, learn more about mesothelioma and the link with asbestos.
When cancer spreads beyond the place where it first formed, this is metastasis.
Cancer can spread to other parts of the body through the blood. A tumor can also spread by growing into nearby tissues.
Metastatic lung cancer has spread to another part of the body, for example, the liver. In this case, it is still considered lung cancer. Cancer is classified by its place of origin. If a person has breast cancer that reaches a lung, doctors call this metastatic breast cancer.
Often, a doctor will use a chest X-ray when diagnosing cancer. This is because other cancers often spread to the lungs.
Cancer can be visible on lung scans, but the appearance depends on the type of cancer, how far it has spread, and other factors.
What does it mean if a person has metastatic lung cancer? Find out more here.
Lung cancer does not always produce symptoms in the early stages, and this can make it difficult to detect.
A chest X-ray is usually the first test, but it cannot show that the person has cancer.
Fewer than 5% of these growths are cancerous, according to the American Thoracic Society.
Depending on symptoms and risk factors, a doctor may recommend monitoring a growth over time. Or, they may perform other tests to rule out cancer. MRIs and PET scans can provide more detailed information.
A doctor may also send a sample of phlegm to a lab, which will analyze it for cancerous cells. This is called a sputum test.
A lung biopsy is the only way to confirm that lung cancer is present. This involves taking a small sample of lung tissue for examination under a microscope. The results can indicate whether cancer is there and, if so, what type it is.
Who gets lung cancer?
Lung cancer forms when certain genetic changes take place in the body. According to Genetics Home Reference, people are not usually born with these changes. Environmental factors cause them to happen, though some people have a higher risk.
The Centers for Disease Control and Prevention (CDC) note the following risk factors:
- smoking or exposure to secondhand smoke
- a family history of lung cancer
- previous radiation therapy to the chest
- exposure to radiation, pollution, asbestos, or diesel
- exposure to radon or certain other chemicals
- the use of beta carotene supplements
A doctor may order a chest X-ray to diagnose lung cancer.
In the early stages of lung cancer, people often have no symptoms. However, this is when cancer is most treatable. The outlook is usually better with an early diagnosis.
For this reason, doctors may recommend routine chest X-rays for people with a higher risk of lung cancer.
- chest pain
- blood in the mucus
- difficulty breathing
- trouble swallowing and speaking
- loss of appetite and weight loss
- swelling in the face or neck
As lung cancer grows and spreads, other symptoms appear.
Metastatic lung cancer can cause a wider range of symptoms, depending on the affected part of the body.
Treatment options depend on the type of lung cancer, the stage, and factors specific to each individual.
The options include:
Chemotherapy: This involves taking drugs that can kill cancer cells.
Surgery: In some cases, a surgeon can remove tumors and cancerous tissue.
Targeted therapy: This involves taking drugs that target specific genes or other factors that promote tumor growth.
Immunotherapy: This strengthens the immune system to better defend the body against cancer.
Radiation therapy: This involves using either radioactive material or beams of radiation to destroy cancer cells.
Doctors often prescribe a combination of these methods. The doctor will work with the person to develop a suitable treatment plan.
Lifestyle adjustments, such as eating healthfully, getting exercise, and quitting smoking, may also help prolong life and reduce the severity of symptoms.
What does chemotherapy involve? Learn more here.
The outlook for lung cancer depends on:
- the stage of the cancer at diagnosis
- the type of cancer
- the age and overall health of the individual
According to the American Lung Association, a person with lung cancer that has not spread beyond the lungs has a 56% chance of living for at least another 5 years after the diagnosis. However, doctors only diagnose 16% of lung cancer cases in this early stage.
ASCO point out that the number of deaths from lung cancer fell by 3–4% each year from 2012 to 2016. One reason is that fewer people are smoking. The other is that new treatments are improving the outlook for people with lung cancer.
Quitting smoking and avoiding secondhand smoke are the best ways to prevent lung cancer. A doctor can advise about effective ways to do this.
Here, learn five ways to quit smoking.
In addition, products that can help people quit smoking are available for purchase online.
I have been smoking for 40 years and now I am 60. I cough a lot and I am starting to worry about my health. Will it really help if I give up now?
Yes. In addition to the effects on the pulmonary system, the benefits of quitting smoking on the cardiovascular system can be seen as early as weeks after quitting. This results in a decrease in risks of heart attacks and strokes.Seunggu Han, MD Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.