Saint Alphonsus Health System

Understanding Cancer

Key Points

  • Although cancer is the second leading cause of death in the United States, the survival rate for many types of cancer has improved in recent years.
  • Cancer occurs when cells do not stop growing (dividing) and do not die when they should. Cancer cells can spread (metastasize) to distant parts of the body through the bloodstream or lymphatic system.
  • Cancer is the result of changes in the genes that control normal cell growth and death. These changes may be inherited, or may result from lifestyle factors.
  • People can reduce their risk of cancer by adopting a healthy lifestyle. Screening exams can detect some pre-cancerous conditions. In addition, people who notice certain signs and symptoms that may suggest cancer should see a doctor.
  • Cancer can be treated with surgery, radiation therapy, chemotherapy, hormones and/or substances that improve the immune system's ability to fight cancer.
  • Clinical trials (research studies with people) are a treatment option for cancer patients.

Almost 1.4 million new cases of invasive cancer will be diagnosed in the United States every year, and over half a million people will die of the disease. Cancer is the second leading cause of death in this country. However, improvements in cancer detection, diagnosis and treatment have increased the survival rate for many types of cancer. About 65 percent of all people diagnosed with cancer will be alive five years after treatment.