UROLOGICAL ONCOLOGY

Should we replace the Gleason score with the amount of high-grade prostate cancer?
Vis AN, Roemeling S, Kranse R, Schröder FH, van der Kwast TH
Department of Urology, Erasmus Medical Center, Rotterdam, The Netherlands
Eur Urol. 2007; 51: 931-9

• Objectives: The stage and grade shift of currently diagnosed prostate cancer has led to a diminished prognostic power of the Gleason score system. We investigated the predictive value of the amount of high-grade cancer (Gleason growth patterns 4/5) in the biopsy for prostate-specific antigen (PSA) and clinical relapse after radical prostatectomy.
• Methods: PSA-tested participants (N = 281) of the European Randomized Study of Screening for Prostate Cancer (ERSPC) who underwent radical prostatectomy were analyzed. Besides clinical features, and serum-PSA, histopathologic features as determined in the diagnostic biopsy and matching radical prostatectomy specimen were related to patient outcome.
• Results: At a median follow-up of 7 yr, 39 (13.9%), 24 (8.5%), and 12 (4.3%) patients had PSA >/= 0.1 ng/ml, PSA >/= 1.0 ng/ml, and clinical relapse after radical prostatectomy, respectively. Using Cox proportional hazards, PSA level (p = 0.002), length of tumour (p = 0.040), and length of high-grade cancer (p = 0.006) in the biopsy, but not Gleason score, were independent prognostic factors for biochemical relapse (PSA >/= 0.1 ng/ml) when assessed as continuous variables. In radical prostatectomies, the proportion of high-grade cancer (p < 0.001) was most predictive of relapse (PSA >/= 0.1 ng/ml). For PSA >/= 1.0 ng/ml and clinical relapse, the amount of high-grade cancer, both in the biopsy specimen (p = 0.016 and p = 0.004, respectively) and radical prostatectomy specimen (p = 0.002 and p = 0.005, respectively), but not Gleason score, was an independent predictor.
• Conclusions: In biopsy and radical prostatectomy specimens of surgically treated prostate cancer, the amount of high-grade cancer is superior to the Gleason grading system in predicting patient outcome. We propose that, in addition to the Gleason score, the amount of Gleason growth patterns 4/5 in the biopsy (whether absolute length or proportion) should be mentioned in the pathology report.
  
  
• Editorial Comment
  Gleason sum score is widely used for tayloring treatment to patients with prostate carcinoma. In this report, the authors compare the usual Gleason sum score to the amount of Gleason 4/5 (aggressive growth pattern) in the biopsy in predicting outcome after radical prostatcetomy. They found that the proportion of aggressive tumor correlates very well with PSA relapse after radical prostatectomy and suggest to indicate this proportion in the pathological report.
  Indeed, from these data and other reports this approach can only be emphasized and every pathologist should be asked for this additional service. The only caveat may be the difficulty to define the proportion of aggressive tumor growth (Gleason 4/5) in biopsies with small amount of tumors. Still, this approach may be very helpful in clinical practice.

Dr. Andreas Bohle
Professor of Urology
HELIOS Agnes Karll Hospital
Bad Schwartau, Germany
E-mail: boehle@urologie-bad-schwartau.de