Predictors of cancer on repeat prostate biopsy: A contemporary UK series

Summary 

Objective

The aim of our study was to review current rebiopsy practice across our cancer network and to develop evidence-based guidelines to assist clinicians and patients in taking the decision when to proceed to repeat prostate biopsy in a UK healthcare setting.

Methods

We conducted case note review of patients who underwent more than one prostate biopsy over a 5-year period (2000–2005) within a single cancer network.

Results

Multivariate logistic regression analysis demonstrated that the factors from the first biopsy associated with the diagnosis of cancer at rebiopsy were PINATYP (RR=4.1, p<0.05), ASAP (RR=3.9, p<0.05), HGPIN (RR=3.8, p<0.05), abnormal DRE (RR=2.2, p<0.05). Histological evidence of inflammation reduced the risk of cancer on rebiopsy in comparison with benign prostatic tissue. Age below 70 also resulted in a reduced risk.

PSA doubling time correlated with a final diagnosis of cancer on Pearson correlation test (coefficient −.011). Only 43 patients (21.5%) had the average PSA measurement frequency within 6 months; however, the average PSA measurement frequency was not predictive of cancer diagnosis (between groups ANOVA, p>0.05).

61 patients were diagnosed with prostate cancer. 38 patients (62%) received definitive local therapy with 13 patients (21%) receiving no immediate treatment.

Conclusions

Our retrospective series has defined predictors of a cancer diagnosis on repeat biopsy in a UK population. The findings of this study will form the basis of our local guidelines for the time-being, but there is scope for a large prospective study utilizing the 10 or 12 core protocol recommended by NICE to ascertain the most appropriate frequency of PSA testing and the indications for repeat biopsy.

Keywords: PSA, Prostate biopsy, Prostate cancer