Metastasis

Metastasis is the multistep process by which cancer cells within a malignant tumour escape and form secondary tumours (metastases) at a distant organ in the body. Successful invasion of blood or lymphatic vessels by malignant cells precedes the formation of a micrometases at the new site before complete colonisation to the secondary tumour. Resistance to apoptosis is an attribute thought to enable such cells to survive in a foreign environment.