Tumor progression defines the process of invasiveness which leads to settlement and growth of a tumor cell in an organ that is distant from the site of the primary tumor. Such a “secondary” tumor is called metastasis.
Loss of contact between the individual tumor cell and the tissue of the primary tumor
Penetration through the basal lamina of the primary tumor
Invasion of blood and/or lymphatic vessels
Adaptation to the blood pressure
Adhesion to vessel endothelia, extravasation, embedding, and...