Lung Cancer; Types, Causes, Symptoms, Diagnosis & Treatment

The body is made up of millions of cells of different types sizes and functions. These are divided forming tissues and organs. When cells age or suffer some damage, they die and are replaced by new ones.

In some cases, this process may go out of control. The cells contain genetic material, which determines how each of them grows, divides and relates to the others. When this genetic material is damaged, growth and cell division gets out of control. Thus, cells do not die when they should die and new cells are created that the body does not need. These cells form what is known as a tumor, which escapes the control mechanisms of the immune system.

When the cells of this tumor have the ability to spread invading other nearby tissues, it is a malignant tumor or cancer. If the mutated cells originate in the lung, we talk about lung cancer.

Lung cancer is the second most common cancer in men and women behind prostate cancer and breast cancer respectively. Lung cancer is the leading cause of death from cancer worldwide. Every year, more people die from lung cancer than from cancers of the colon, breast, and prostate combined.

1Types of lung cancer

Lung cancer is classified based on the type of cell that causes the tumor. In order to determine this nature, it is necessary to carry out a histological diagnosis, which consists of the study of a portion of tissue under a microscope.

There are mainly two different types of lung cancer:

  • Small cell lung carcinoma: represents approximately 20% of lung tumors that are diagnosed and is closely related to smoking. It is usually very aggressive and spreads rapidly to other parts of the body. It tends to present a better response to chemotherapy than other types of lung cancer.
  • Non-small cell lung carcinoma: It represents approximately 80 percent of diagnosed lung tumors. It is subdivided into three types:

» Squamous cell carcinoma: Represents 40% of lung cancers, being the most common type. They are centrally located and their growth is relatively slow causing necrosis (irreversible tissue death) and cavitation (pathological formation of cavities in tissues or organs).

» Non-squamous carcinomas:

– Adenocarcinoma: It represents 30% of cases of lung cancer and is the most frequent in women. This tumor is located in the periphery of the pulmonary tissue and can affect the pleura and the chest wall.

– Large cell carcinoma: Represents 10% of lung tumors. It has characteristics other than squamous cell carcinoma and adenocarcinoma.