Objective: to describe the follow-up of men with an elevated 'Prostate Cancer gene 3' (PCA3, a promising novel tool for prostate cancer detection) and a negative repeat biopsy (Bx-), as a previous study in men with one or two negative Bx (Bx-) scheduled for repeat Bx showed that a higher PCA3 score corresponded with a higher probability of a positive repeat Bx (Bx+).
Patients and methods: this study comprised an analysis of the follow-up of men with a PCA3 score of ≥ 20 and a repeat Bx-, after which a follow-up Bx was taken. The initial study data in 463 men were also analysed to compare characteristics of: (i) men with a PCA3 score of ≥ 20 and ≥ 35 and a repeat Bx+, vs those with a Bx-; and (ii) men with a repeat Bx- and a PCA3 score of ≥ 20 vs <20 and a PCA3 score of ≥ 35 vs <35.
Results: a follow-up Bx was taken in 51 selected men; the Bx+ rate was 55%. Men with a follow-up Bx+ had a higher PCA3 score (mean 69.5, median 50.4) than those with a Bx- (mean 37.7, median 28.2; P < 0.001). They also more often had high-grade prostatic intraepithelial neoplasia (HGPIN) at the previous Bx (46% vs 17%; P= 0.029). Men with a PCA3 score of ≥ 35 and a repeat Bx+ had a higher PCA3 score (mean 113.9, median 75.7) than those with a Bx- (mean 87.3, median 56.9; P= 0.047). Men with a repeat Bx- and an elevated/high PCA3 score more often had HGPIN than men with a low PCA3 score.
Conclusions: an elevated/high PCA3 score can predict prostate cancer in men with one or two previous Bx-. If the repeat Bx is negative, an elevated/high PCA3 score combined with HGPIN might predict prostate cancer at the follow-up Bx.