Cancer grows as cells multiply over and over

Benign and cancerous (malignant) tumours Tumours (lumps) can be benign or cancerous (malignant). Benign means it is not cancer. Benign tumours: usually grow quite slowly don’t spread to other parts of the body usually have a covering made up of normal cells Benign tumours are made up of cells that are quite similar to normal cells. They only cause a problem if they: grow very large become uncomfortable or painful are visible and unpleasant to look at  press on other body organs take up space inside the skull (such as a brain tumour) release hormones that affect how the body works