Cancer is a group of over 100 diseases characterized by the uncontrolled growth and spread of abnormal cells, which can form tumors and invade other parts of the body. It can start in almost any organ or tissue. If it spreads to other organs, it is called metastasizing, and is a major cause of death from cancer. In 2022, there were almost 20 million new cases of cancer worldwide. Lung cancer was the most frequently diagnosed (almost 2.5 million new cases), followed by breast cancer (2.29 million), colorectal cancer (1.93 million), prostate cancer (1.47 million), and stomach cancer (968,784).
Cancer is the second leading cause of death globally. In 2020, cancer accounted for nearly 10 million deaths worldwide, or 1 in 6 deaths. However, survival rates are improving due to advancements in screening, treatment, and prevention. From 2018 to 2022, overall cancer death rates decreased by 1.7% per year among men, 1.3% per year among women, and 1.5% per year among children ages 0–14. Between 30% and 50% of cancer deaths could be prevented by modifying or avoiding key risk factors like tobacco use, unhealthy weight, alcohol consumption, and lack of physical activity.
