What is a tumor?

Cancer is a group of more than 500 different diseases. It can develop almost anywhere in any body part.
Cancer can start in any part of the body. When cancer cells form a lump or growth, it is called a cancerous tumour. A tumour is cancerous when it:

  • grows into nearby tissues
  • has cells that can break away and travel through the blood or lymphatic system and spread to lymph nodes and distant parts of the body.
  • Lumps that are not cancer are called benign
  • Lumps that are cancer are called malignant

The latter process is called metastasizing and is a major cause of death from cancer. A neoplasm and malignant tumour are other common names for cancer.Cells are the basic units that make up the human body. Cells grow and divide to make new cells as the body needs them. Usually, cells die when they get too old or damaged. Then, new cells take their place.

Non-cancerous tumours

Tumours that are not cancerous are called non-cancerous tumours. Non-cancerous tumours just like:

  • stay in one place and don’t spread to other parts of the body (no growth)
  • don’t usually come back after they are removed (not repeat)
  • tend to have a regular and soft (smooth) shape and have a covering called a capsule
  • may be moved easily in the tissue


  • Benzene and other chemicals and toxins
  • Drinking too much alcohol
  • Environmental toxins, such as certain poisonous mushrooms and a type of poison that can grow on peanut plants (aflatoxins)
  • Excessive sunlight exposure
  • Genetic problems
  • Obesity
  • Radiation exposure
  • Viruses