A Higher Number of Circulating Tumor Cells (CTC) in Peripheral Blood Indicates Poor Prognosis in Prostate Cancer Patients - A Meta-analysis

Objective: The prevalence of prostate cancer (PCa) is high and PCa is the most common cutaneous cancer in men worldwide. Despite extensive research efforts, very few biomarkers of PCa have been introduced to date in clinical practice. A meta-analysis was performed on the most recently reported CTC to assess its prognostic effect and to elucidate whether its detection in the peripheral blood of patients diagnosed with metastatic, castration-resistant prostate cancer (CPRC) and Hormone Refractory Prostate Cancer (HRPC) can be used as a prognostic factor for survival.
Methods: We searched Science Direct, EMBASE, PubMed, and Cell Research databases for studies that assessed the prognostic relevance of the presence number of circulating tumor cells (CTC) detection in the peripheral blood (PB). A fixed effects model with relative risk (RR) and 95% confidence interval (95% CI) is used for analysis.
Results: A total of 4 studies, including 486 patients, were eligible for final analysis. Pooled analysis indicated the presence number of CTC per 7.5 ml peripheral blood is associated with a poor survival rate (RR=2.51, 95% CI 1.96-3.21).
Conclusion: The unfavorable count (presence of 5 or more CTCs per 7.5 ml peripheral blood) was associated with poor overall survival in patients with PCa. CTC counts can be used as an accurate and independent predictor of survival rate in patients with PCa.