PATHOLOGY

Relationship between Primary Gleason Pattern on Needle Biopsy and Clinicopathologic Outcomes among Men with Gleason Score 7 Adenocarcinoma of the Prostate
Gonzalgo ML, Bastian PJ, Mangold LA, Trock BJ, Epstein JI, Walsh PC, Partin AW
Department of Urology, James Buchanan Brady Urological Institute, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
Urology. 2006; 67: 115-9

• Objectives: To examine the relationship among needle biopsy primary grade, prostatectomy grade, and postprostatectomy biochemical recurrence among men with Gleason score 7 disease.
• Methods: We identified 320 men with Gleason score 7 tumors on prostate biopsy treated with radical prostatectomy between 1991 and 2001 by a single surgeon. None of these patients had received neoadjuvant or adjuvant hormonal therapy or radiotherapy. The chi-square test and Kaplan-Meier method were used to evaluate the correlation among biopsy Gleason score, prostatectomy Gleason score, and biochemical recurrence.
• Results: A total of 252 (79%) and 68 (21%) men had primary Gleason pattern 3 and 4 identified on needle biopsy, respectively. Of the patients with Gleason pattern 3+4 tumors on biopsy, 24% were upgraded to primary pattern 4 or more on final pathologic analysis. Of the patients with Gleason pattern 4+3 tumors on biopsy, 47% were downgraded to primary pattern 3 or less on final pathologic analysis. The actuarial risk of biochemical prostate-specific antigen recurrence was significantly lower among patients with Gleason pattern 4+3 on biopsy, if the prostatectomy Gleason score was downgraded to 3+4 or less (p = 0.03).
• Conclusions: Approximately 47% of men with a diagnosis of Gleason pattern 4+3 on needle biopsy are downgraded at radical prostatectomy and will have biochemical prostate-specific antigen recurrence-free outcomes similar to patients originally diagnosed with Gleason pattern 3+4 adenocarcinoma. This group of patients may benefit from definitive treatment such as radical prostatectomy for management of their disease.
  
  
• Editorial Comment
  Gleason score 7 may result from 3+4=7 or 4+3=7. Data regarding the importance of the percentage of Gleason 4 pattern in Gleason score 7 tumors are rapidly expanding but still controversial (1). In recently generated nomograms, patients with Gleason scores of 4+3 and 3+4 are stratified differently, underscoring the importance of the relative amount of pattern 4 (2). Whether or not the actual percentage of pattern 4 tumor should be included in the report is not clear based on the data published to date and, if this emerges as an important parameter, meaningful discriminatory cut-off points for the percentage of pattern 4 will need to be defined.
  In the article surveyed, most frequently there is downgrading of patients originally graded as Gleason pattern 4+3=7. In 24% of the patients with Gleason pattern 3+4 tumors on biopsy were upgraded to primary pattern 4 or more on final pathologic analysis, and approximately 47% with a diagnosis of Gleason 4+3 on needle biopsy were downgraded at radical prostatectomy. The latter group had biochemical prostate-specific antigen recurrence-free outcomes similar to patients originally diagnosed with Gleason pattern 3+4 adenocarcinoma.

References
1. Amin M, Boccon-Gibod L, Egevad L, Epstein JI, Humphrey PA, Mikuz G, et al.: Prognostic and predictive factors and reporting of prostate carcinoma in prostate needle biopsy specimens. Scand J Urol Nephrol Suppl. 2005; 216: 20-33.
2. Makarov DV, Sanderson H, Partin AW, Epstein JI: Gleason score 7 prostate cancer on needle biopsy: is the prognostic difference in Gleason scores 4 + 3 and 3 + 4 independent of the number of involved cores? J Urol. 2002; 167: 2440-2.

Dr. Athanase Billis
Full-Professor of Pathology
State University of Campinas, Unicamp
Campinas, São Paulo, Brazil