The lungs

When we breathe in, air passes from our nose or mouth through the windpipe (trachea), which divides into two tubes (airways), one going to each lung. These are known as the right and left bronchus.

They divide to form smaller tubes called bronchioles, which carry air through the lungs. At the end of the bronchioles are millions of tiny air sacs called alveoli.

In the alveoli, oxygen is absorbed from the air we breathe in and passes into the bloodstream to be circulated around the body.

Carbon dioxide is a waste gas that needs to be removed from the body. It passes from the bloodstream into the alveoli and is then breathed out from the lungs.

The right lung has three main areas (known as lobes) and the left lung has two. Many lung cancers start in the cells lining the bronchi and are called carcinomas of the bronchus.

Structure of the lungs and pleura
Structure of the lungs and pleura

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The lungs are covered by a membrane, or lining, called the pleura, which has an inner and outer layer. The inner layer covers the lungs. The outer layer lines the ribcage and the diaphragm – a sheet of muscle that separates the chest from the abdomen. The pleura produces a fluid that acts as a lubricant, which helps you to breathe easily and allows the lungs to move in and out smoothly.

Back to Lung cancer

Types of lung cancer

The main types of primary lung cancer are small cell lung cancer and non-small cell lung cancer. They are treated differently.

Cancer and cell types

Cancers are grouped into types. Types of cancer often behave and respond to treatments in different ways.

How it is treated

There are five main types of cancer treatment. You may receive one, or a combination of treatments, depending on your cancer type.

What is cancer?

There are more than 200 different kinds of cancer, each with its own name and treatment.

Why do cancers come back?

Sometimes, tiny cancer cells are left behind after cancer treatment. These can divide to form a new tumour.