Aim: To test if Ki67 expression is prognostic for biochemical recurrence (BCR) after radical prostatectomy (RP).
Methods: Ki67 immunohistochemistry was performed on tissue microarrays constructed from specimens obtained from 464 men undergoing RP at the Durham and West LA Veterans Affairs Hospitals. Hazard ratios (HR) for Ki67 expression and time to BCR were estimated using Cox regression.
Results: Ki67 was associated with more recent surgery year (p < 0.001), positive margins (p = 0.001) and extracapsular extension (p < 0.001). In center-stratified analyses, the adjusted HR for Ki67 expression and BCR approached statistical significance for west LA (HR: 1.54; p = 0.06), but not Durham (HR: 1.10; p = 0.74).
Conclusion: This multi-institutional 'real-world' study provides limited evidence for the prognostic role of Ki67 in predicting outcome after RP.
Keywords: Ki67; biochemical recurrence; castration-resistant prostate cancer; immunohistochemistry; metastases; prostate cancer; tissue microarray.