The spread of cancer cells from the original tumor to a distant part of the body, where they establish new cancerous growths.
Cancer cells can spread through the bloodstream or lymphatic system and reach other organs or tissues. A metastatic tumor retains characteristics of the original cancer; for example, breast cancer that spreads to the liver remains breast cancer, not liver cancer.
Metastasis is an important feature of many advanced cancers and can significantly affect treatment and prognosis.
QUICK FACT
A cancer found in another organ is not necessarily a new cancer originating there. If breast cancer spreads to the lungs, the resulting tumors are metastatic breast cancer.
COMMONLY CONFUSED WITH
Invasion: growth of malignant cells into nearby tissues; metastasis specifically involves spread to a distant site.
SEE ALSO