Association between BK polyomavirus and prostate cancer: a systematic review and meta-analysis

Prostate cancer (PCa) is the second most commonly diagnosed malignancy in men worldwide, but the role of viral infection, particularly BK polyomavirus (BKPyV), remains controversial. To clarify this association, we conducted a systematic review and meta-analysis of 23 studies published between January 1, 2000, and May 1, 2025. The pooled prevalence of BKPyV in PCa tissues was 22% (95% CI: 12-34%; I²= 96.27%), indicating that the inter-study heterogeneity is high. Eleven case-control studies showed that BKPyV infection was associated with increased odds of PCa (pooled OR = 3.04, 95% CI: 2.15-4.30; I²= 31.7%). Subgroup analyses by specimen type, detection method, molecular target, study location, and Gleason score demonstrated a consistent positive association, although residual heterogeneity persisted. Because all included studies relied on PCR-based detection, the identified viral DNA cannot distinguish episomal, integrated, defective, or transcriptionally active states, nor establish temporal order or causality. Overall, BKPyV may represent a plausible cofactor or context-dependent marker in PCa, and the observed pattern is compatible with several hypotheses, including hit-and-run, microenvironment driven phenomenon, and a mixed phenomenon. Standardized molecular assays and more complete clinicopathological annotation are needed in future studies.

https://www.crd.york.ac.uk/PROSPERO/view/CRD420251179044, identifier CRD420251179044.