In order for a tumor to spread to distant sites, cancer cells must detach from the original tumor, pass into the circulation, enter into distant tissues, survive and grow in their new microenvironment.
In each of these steps, the cancer cells face new challenges, which they need to cope with by acquiring new properties. The most difficult barriers to metastasis are the escape from a primary tumor and the colonization in a foreign tissue. Traveling through the circulation is relatively easy in comparison.
Review Date:
1/1/2025 Reviewed By: Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. |