What is Cancer?

Cancer is defined as a disease in which abnormal cells divide uncontrollably and invade other tissues.

Cancers begin in the body’s basic unit of life, the cell. Many types of cells make up the body’s composition. These cells grow and divide to provide the body with the extra cells needed to stay healthy. When cells become old or damaged, they are replaced with new ones. This process occasionally goes wrong and the DNA of a cell becomes changed or damaged. When this happens, the old and damaged cells do not die off as they should and new cells are produced when the body has no need for them. In turn, these cells form a mass of tissue called a tumor.

There are more than 100 different types of cancer, being named for the type of cell or organ in which they originate from. They can, however, be grouped into a few broader, main categories. They are:

  • Carcinoma – Cancer that originates in the skin and in tissues that line the internal organs. This is the most common of the cancers.
  • Central Nervous System – Cancers that start in the tissues of the spinal cord and brain.
  • Sarcoma – Cancer that begins in the bones, cartilage, muscle, vascular, or hematopoietic tissues. These types of cancer are rare.
  • Leukemia – Cancer originating from an increase of white blood cells in the blood or bone marrow.
  • Lymphoma/Myeloma – Cancers from abnormal formation of white blood cells in bone marrow and the blood.