Lung Cancer: Symptoms, Stages, Signs, Diagnosis, Causes, Treatment, Survival Rates

Lung cancer is one of the most common and most deadly cancers. There are two types of lung cancer: small cell lung cancer and non-small cell lung cancer. What are their symptoms and how is it treated?

Lung Cancer: Symptoms, Stages, Signs, Diagnosis, Causes, Treatment, Survival Rates
Lung Cancer: Symptoms, Stages, Signs, Diagnosis, Causes, Treatment, Survival Rates

Definition: what is lung cancer?

Discover our latest podcast

In order to understand lung cancer, it is necessary to first known about the respiratory system. The lungs receive air through the trachea which is split up into two bronchi, one for each lung. Each of these branches out more and more until they form bronchiole, which then finish with a cluster of small sacs, known as alveoli. The role of the alveoli is to take oxygen from the inhaled air and transfer it into the blood and also to take the carbon dioxide to remove it from the lungs during exhalation.

Lung cancer is a particularly high risk that can easily spread due to the fact that the blood has to passes through the lungs in order to be oxygenated, and because the lungs are in close contact with so many blood vessels and lymphatics.

There are two types of lung cancer. “Small cell” lung cancer represents about 20% of cases and it is likely that at the time of diagnosis, the cancer has already spread elsewhere in the body. It grows quickly and is often impossible to treat with surgery. For this type of cancer, chemotherapy and radiotherapy are preferred.

“Non-small cell” lung cancer represents around 80% of cases, it is more easily detected and treated than small cell and it develops slower. This type of cancer has 3 sub groups: adenocarcinoma, squamous cell carcinoma and undifferentiated non-small cell carcinoma.

Causes: what causes lung cancer?

Even if the exact causes of lung cancer aren’t exactly known, there are some supporting factors for this disease, among them being tobacco use which is solely responsible in 80 to 90% of lung cancer cases. This is because a smoker has a risk that is ten times higher of contracting this cancer than a non-smoker. Passive smoking increases the risk of cancer by 26%.

Another factor is people exposed to cancerous particles in the air where they work, such as asbestos, arsenic or cadmium. All these are susceptible for triggering cancer. This is why for businesses which use these products, it is crucial that they protect their employees.

Finally, other lung diseases can be risk factors, such as obstructive pulmonary disease, silicosis or even tuberculosis.

The symptoms of lung cancer

In the majority of cases, the cancer doesn’t present any symptoms. This absence of symptoms is explained by the fact that the lungs are not too affected and as a consequence the tumours are not felt when they affect the pleural cavity or support on neighbouring organs which then give signs of compression. It is for this reason that these cancers are often detected late.

However, there are some signs of lung cancer that can lead to diagnosis:

- harsh cough, which gets worse or doesn’t disappear

- pains in the thorax which enhance during coughing or deep breathing

- wheezy breathing

- rapid shortness of breath

- husky voice for nearly a month

This cancer also involves fatigue, weight loss, a prolonged fever, headaches, phlebitis and nerve problems with mental confusion among others.

Treatment: how to care for lung cancer?

If cancer is suspected, the doctor will give the patient a chest X-ray. This makes it possible to visualise the tumour damage that is present in the lungs but doesn’t determine the nature of the tumour (mild or malignant). The radiogram doesn’t identify all tumours, especially the smallest ones, which is why doctors generally carry out a chest C.T. scan as a follow up.

Even though treatments exist, lung cancer is one of the deadliest. For those who are affected, the survival rate is 5 years after diagnosis: 17% in women and 14% in men. And even if patients respond well to treatment at first, it is very common that they will relapse in the months or years that follow.

Nowadays, there are three treatments for lung cancer: surgery, radiotherapy and chemotherapy. They can be prescribed alone or combined depending on the wide diversity of cases.

When the tumour is localised and can surely be removed, surgery can be carried out. When possible, it can either involve removing a lobe of the lung or the lung as a whole, according to the size, the localisation and the advancement of the tumour. (It is important to note that we have two lungs, the left being made up of two lobes, the right of three). Hospitalisation only takes a few days, but recovery can take several months.

For those who are diagnosed with an advanced stage of cancer, it is often too late to have surgery as the tumour is no longer localised but disseminated. The doctor can therefore suggest chemotherapy and/or radiotherapy in order to slow down the growth of the tumour(s). Indeed, these treatments can extend life expectancy, but they can cause side effects.

Breast Cancer: Symptoms, Signs, Causes, Stages, Treatment, Survival Rate Breast Cancer: Symptoms, Signs, Causes, Stages, Treatment, Survival Rate