How does cancer start?

Cancer is a complex disease that involves the uncontrolled growth and spread of abnormal cells. It can start due to various factors, including genetic mutations, exposure to carcinogens, and certain lifestyle choices. Here's a step-by-step explanation of how cancer typically begins: 1. Cell Division: Normally, cells in the body divide and grow in a controlled manner. They have a set lifespan and are replaced by new cells when they die. 2. Mutation: Sometimes, errors can occur in the genetic material (DNA) of a cell when it divides. These errors are known as mutations. Most mutations are harmless, but some can interfere with the cell's normal processes. 3. Growth Signal Ignition: Mutations can lead to the cell ignoring signals that tell it to stop growing or to die. Instead, the cell continues to grow and divide. 4. Uncontrolled Growth: As these abnormal cells continue to grow and divide, they form a mass known as a tumour. 5. Benign vs. Malignant: Not all tumours are cancerous. Benign tumours remain localized and do not invade nearby tissues or spread to other parts of the body. However, if the tumour is malignant, it can invade and damage healthy tissue and organs. 6. Metastasis: The most dangerous aspect of malignant tumours is their ability to spread to other parts of the body through the blood and lymph systems. This process is called metastasis. 7. Cancer Development: Over time, the accumulation of mutations can lead to the development of cancer. This process can be influenced by a combination of genetic predisposition and environmental factors.

Your body is made up of 100 million million cells. Cancer can start when just one of them begins to grow and multiply too much. The result is a growth called a tumour. Benign tumours are localised growths - they only cause problems if they put pressure on nearby tissues, such as the brain.