As of 2015, approximately 8 million people die from cancer annually, states the Centers for Disease Control and Prevention. Additionally, about 14 million people are diagnosed with cancer every year. As much as one-third of cancer cases are potentially preventable, but lack of education and services limit worldwide progress.
Cancer occurs when a cell's DNA becomes damaged and mutates in a manner that affects healthy cell division, according to MedicineNet. Instead of dying, these cancerous cells continue to divide and spread, often forming a tumor. Malignant tumors, or cancerous ones, display uncontrolled growth, while benign tumors do not spread, and they typically cause no harm to the body. Some types of cancer, such as leukemia, do not exhibit tumors.