This study focuses on individuals have been diagnosed with advanced, metastatic, castration-resistant prostate cancer that has progressed despite prior treatment. The purpose of the study is to collect blood, tumor tissue, and bone marrow samples from prostate cancer patients to monitor their circulating tumor cell numbers as a biomarker. Circulating tumor cells (CTCs) are rare cells in the bloodstream that have broken off from a tumor and could possibly lead to future metastases (spreading of cancer). A biomarker is a biological molecule found in blood, other body fluids, or tissues that may be a sign of a condition or disease. Researchers aim to explore whether circulating tumor cells can be utilized as a biomarker. The results of this pilot study will enable researchers to further confirm that very small nuclear CTCs may be able to help predict the onset of cancer spreading to the liver or lungs before a standard scan is able to detect this event.

• CS Cancer at Beverly Hills
• CS Cancer at Cedars-Sinai Medical Center