The process of prostate cancer metastasizing from the prostate gland to other parts of the body is called “disease progression.” Disease progression also includes the emergence of new metastases, as well as the growth (enlarging) of existing metastases. Disease progression is measured by evidence seen on scans and on PSA progression.
Other than for Provenge, disease progression is one measure of treatment failure.
Exactly how prostate cancer spreads is not yet well characterized. It is often thought to spread either through the vascular system or through the lymphatic system. It may use both. The end result of the spread is development of tumors in other parts of the body, both near and distant from the location of the prostate gland. Bones are the most common sites for metastases to develop, but prostate cancer can also spread to soft tissue organs.