Cancer /ˈkænsə(r)/ is a class of diseases in which a group of cells display uncontrolled growth (division beyond the normal
limits), invasion (intrusion on and destruction of adjacent tissues), and sometimes metastasis (spread to other locations
in the body via lymph or blood). These three malignant properties of cancers differentiate them from benign tumors, which
are self-limited, and do not invade or metastasize. Most cancers form a tumor but some, like leukemia, do not.