Prevalence of circulating tumor cells in localized prostate cancer.

BACKGROUND Circulating tumor cells (CTC) predict overall survival in patients with metastatic prostate cancer. The objective of this study is to measure CTC before radical prostatectomy in intermediate- and high-risk prostate cancer patients. MATERIALS AND METHODS The study accrued 12 patients and 10 provided adequate peripheral blood sample. Blood was drawn preoperatively and assayed for CTC using the CellSearch system. Patients were categorized as CTC positive (≥ 1 CTC) or CTC negative (no CTC). RESULTS Median age was 64.5 years (range 49-77 years), median prostate specific antigen was 7.4 ng/ml (range 5.7-25.7 ng/ml). Seven patients had intermediate-risk and 3 patients had high-risk prostate cancer. One patient was found to be CTC positive. CONCLUSIONS Our pilot study shows that CTC are rare in patients with clinically localized disease despite intermediate- to high-risk features. CTC may not be the optimal marker to predict prognosis or detect residual disease after radical prostatectomy.