DNA content in the diagnostic biopsy for benign-adjacent and cancer-tissue areas predicts the need for treatment in men with T1c prostate cancer undergoing surveillance in an expectant management programme

Isharwal, S., D.V. Makarov, H.B. Carter,J.I. Epstein, A.W. Partin, P. Landis, C. Marlow, and R.W. Veltri
BJU International, Vol. 105, no. 3, pp. 329-333. DOI: 10.1111/j.1464-410X.2009.08791.x

Objective: To assess the DNA content in benign-adjacent and cancer-tissue areas of a diagnostic biopsy, to predict which patients would subsequently develop an unfavourable biopsy necessitating treatment for prostate cancer in the expectant management (EM) programme.

Patients and Methods: Of 71 patients who had benign-adjacent and cancer-tissue areas of diagnostic biopsies available, 39 developed unfavourable biopsies (Gleason score ≥7, Gleason pattern 4/5, three or more cores positive for cancer, >50% of any core involved with cancer), while 32 maintained favourable biopsies on annual surveillance examination (median follow-up 3.7 years). DNA content was measured on Feulgen-stained biopsy sections using an automatic imaging system (AutoCyteTM, TriPath Imaging Inc, Burlington, NC, USA). Cox proportional-hazard regression and Kaplan-Meier plots were used to identify significant predictors for unfavourable biopsy conversion.

Results: Univariately, DNA content measurements i.e. an excess of optical density (OD) in the benign-adjacent tissuer area, and the sd of the OD in the cancer tissue were significant, with a hazard ratio and 95% confidence interval of 2.58 (1.17–5.68; P = 0.019) and 5.36 (1.89–15.24; P = 0.002), respectively, for predicting unfavourable biopsy conversion that required intervention. Also, several other DNA content measurements in benign-adjacent and cancer-tissue areas showed a trend to statistical significance. Further, benign-adjacent excess of OD (3.12, 1.4–6.95; P = 0.005) and cancer sd of OD (5.88, 2.06–16.82; P = 0.001) remained significant in the multivariate model to predict unfavourable biopsy conversion. Patients with benign-adjacent excess of OD > 25.0 and cancer sd of OD of >4.0 had the highest risk for unfavourable biopsy conversion (P < 0.001).

Conclusions: DNA content measurements in the benign-adjacent and cancer-tissue areas appear to be useful for predicting unfavourable biopsy conversion (a recommendation for intervention) on annual surveillance examinations in the EM programme.

Wagner Faculty