Cancer is a broad term used to describe a group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body. It is a leading cause of death worldwide and has a significant impact on individuals, families, and societies. Cancer can affect people of all ages, races, and backgrounds, and it can develop in virtually any part of the body.
Normal cells in the body grow, divide, and die in an orderly manner, forming new cells to replace the old or damaged ones. However, cancerous cells do not follow this normal pattern. Instead, they continue to grow and divide uncontrollably, forming a mass of tissue called a tumor. Not all tumors are cancerous, though; some are benign and do not spread to other parts of the body.
When cancerous cells invade and destroy surrounding tissues or spread to other parts of the body through the bloodstream or lymphatic system, the condition is referred to as metastasis. Metastatic cancer is often more difficult to treat and carries a poorer prognosis.
There are numerous types of cancer, each with its own unique characteristics, risk factors, and treatment approaches. Some of the most common types include breast cancer, lung cancer, prostate cancer, colorectal cancer, and skin cancer. Cancer can also manifest in the blood, such as leukemia, lymphoma, and myeloma.