Metastasis is the process by which the cancerous cells spreads to different parts of the body (spread of tumour from the primary site of origin to different areas of the body).
These cells divide uncontrollably forming a mass of cells called tumor.
This property of is exhibited by malignant tumors.
Since, the cells can break away from the primary site and spread to other sites in the body it can cause tumor in any part of the body.