Does transrectal ultrasonography-guided biopsy of the prostate lead to possible further metastasis via circulating tumor cells?

Background/aim: We evaluate whether transrectal ultrasonography (TRUS)-guided prostate biopsy might lead to spillage of tumor cells into peripheral blood as a result of disruption of the epithelial barrier and ultimately result in metastasis. Materials and methods: Eighty-eight patients underwent TRUS-guided prostate needle biopsy due to prostate-specific antigen (PSA) increase or abnormal digital rectal examination at the Samsun Research and Training Hospital (Samsun, Turkey) between April 2016 and September 2018. Approximately 10 mL of whole blood was collected from patients before, 1 week after, and 1 month after biopsy. Samples were analyzed for CD117 positivity and prostate-specific membrane antigen (PSMA) levels using flow cytometry. Patients with pathologically determined prostate cancer and without CD117 positivity before biopsy were included in the study. The study group thus consisted of 55 patients. Results: Subjects’ PSA levels ranged from 2.3 to 40.0 ng/mL (median: 7.9 ng/mL), and their Gleason score was a median of 7 (range: 5–9). PSMA levels ranged between 9.3 ng/mL and 118.5 ng/mL and CD117 antigen levels between 0 and 5. We detected no CD117- positive cells in blood samples collected 7 days or 1 month after biopsy. Conclusion: We detected no circulating tumor cells in the peripheral circulation following biopsy. Prostate needle biopsy seems to be a safe method in terms of spillage of tumor cells into blood circulation as a possible cause of further metastasis.