Kammerer-Jacquet SF, et al. - Because immunohistochemical testing for Ki-67 improved the prediction of death from prostate cancer in a previous cohort of conservatively treated clinically located prostate cancer, researchers analyzed its validation of use with whole biopsy sections rather than tissue micro-arrays for routine diagnostics. Cases of prostate cancer biopsy have been identified in the UK, treated conservatively between 1990 and 2003. The interquartile hazard ratio for continuous Ki-67 was 1.68 in univariate analysis. Investigators are now advocating the introduction of Ki-67 in clinical practice as a viable and feasible prognostic biomarker. According to findings, Ki-67 association with mortality was highest in grade groups 1 and 2, showing that Ki-67 can be used as a routine biomarker for active surveillance in patients.