The lungs are organs located within the chest cavity that allow oxygen taken in through the respiratory system to mix with the blood and help remove carbon dioxide from the body through the airways. There are two lungs in the chest cavity, one on the right and one on the left.
Due to certain external factors, uncontrolled growth may occur in lung cells. These proliferating cells are completely different from normal lung cells and are harmful. These abnormal cells combine to form lung cancer. This cancer develops in the lungs or airways and, over time, grows further and begins to metastasize—spread to different parts of the body through the blood or lymphatic system. If left untreated, cancer growing in the lungs and spreading to other organs prevents patients from living a healthy life.
Lung Cancer
Lung cancer is one of the most common cancers in the world. In our country, more than 40,000 people are diagnosed with this disease every year. In the United States, the number is 190,000 annually. According to data from the International Agency for Research on Cancer, 2.2 million people worldwide were diagnosed with lung cancer in 2020.
What Are the Causes of Lung Cancer?
Today, it has been clearly established that the most significant cause of lung cancer is smoking and the use of other tobacco products. Other causes include certain chemicals (such as uranium, arsenic, cadmium, chromium, nickel, and asbestos), radon gas found in soil, and radiation exposure.
Additionally, scientific studies have shown that individuals who have never smoked but have been exposed to cigarette smoke for long periods are at an increased risk of developing lung cancer. Other factors include air pollution and exposure to certain chemicals in the workplace.
In general, lung cancer is much less common among individuals who follow healthy lifestyle practices.
What Are the Types of Lung Cancer?
Lung cancers are divided into two main groups: small cell lung cancers and non-small cell lung cancers. Small cell lung cancers are rarer and account for 10–15% of all lung cancers. Non-small cell lung cancers consist of various cell types. The most common among them are adenocarcinomas, epidermoid (squamous cell) carcinomas, and large cell carcinomas. There are also other, less common types.
The classification of lung cancers into these types has important medical reasons. For instance, small cell lung cancers grow and metastasize significantly faster than non-small cell lung cancers. As a result, the treatment approaches for small cell lung cancers differ from those for non-small cell lung cancers, as explained in the treatment section below. Similarly, non-small cell lung cancers are further classified based on cell type. The most common types, adenocarcinomas and squamous cell carcinomas, have distinct diagnostic and treatment methods.
Knowing the cell type of lung cancer helps determine which tests to prioritize and which ones to avoid wasting time on. This enables quicker diagnosis and more effective treatment, thereby improving the chances of success.
