Upgrading the Gleason score in extended prostate biopsy: implications for treatment choice.
OBJECTIVE
To determine the incidence of overestimation of Gleason score (GS) in extended prostate biopsy, and consequently circumventing unnecessary aggressive treatment.


METHODS
This is a retrospective study of 464 patients who underwent prostate biopsy and radical prostatectomy between January 2001 and November 2007. The GS from biopsy and radical prostatectomy were compared. The incidence of overestimation of GS in biopsies and tumor volume were studied. Multivariate analysis was applied to find parameters that predict upgrading the GS in prostate biopsy.


RESULTS
The exact agreement of GS between prostate biopsy and radical prostatectomy occurred in 56.9% of cases. In 29.1% cases it was underestimated, and it was overestimated in 14%. One hundred and six (22.8%) patients received a diagnosis of high GS (8, 9, or 10) in a prostate biopsy. In 29.2% of cases, the definitive Gleason Score was 7 or lower. In cases in which GS was overestimated in the biopsy, tumors were significantly smaller. In multivariate analysis, the total percentage of tumor was the only independent factor in overestimation of GS. Tumors occupying less than 33% of cores had a 5.6-fold greater chance of being overestimated.


CONCLUSIONS
In the extended biopsy era and after the International Society of Urological Pathology consensus on GS, almost one third of tumors considered to have high GS at the biopsy may be intermediate-risk cancers. In that condition, tumors are smaller in biopsy. This should be remembered by professionals involved with prostate cancer to avoid overtreatment and undesirable side effects.
Moreira Leite
Katia Ramos
KR
Laboratory of Medical Investigation - LIM 55, Urology Department, Medical School, Universidade de São Paulo, Brazil.
Camara-Lopes
Luiz H A
LH
Dall'Oglio
Marcos F
MF
Cury
Jose
J
Antunes
Alberto A
AA
Sañudo
Adriana
A
Srougi
Miguel
M
D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D016009:Chi-Square Distribution; D006801:Humans; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000473:pathology* / Q000601:surgery; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000473:pathology* / Q000601:surgery; D012044:Regression Analysis; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D047368:Tumor Burden