[948] Various Morphometric Measurements of Cancer in Needle Prostatic Biopsies: Which Is Predictive of Pathologic Stage and PSA Failure Post-Surgery?

MM Quintal, A Billis, L Meirelles, LLL Freitas, LA Magna, U Ferreira. School of Medicine, University of Campinas (Unicamp), Campinas, Brazil

Background: Cancer extent in needle biopsies (NB) can be measured in a number of ways that have been found to correlate with several clinicopathological findings. It is controversial, however, which one has the highest predictive value. The aim of this study is to investigate which method used to measure tumor is most predictive of stage >pT2 and PSA progression post-surgery.
Design: The study was based on 168 NB with the correspondent radical prostatectomies. All NB were extended with a mean of 11 cores (range 7-20). Tumor extent was evaluated as: number and percentage of positive cores; total length of cancer in mm and the percentage of cancer in all cores; and, the greatest length and the greatest percentage of cancer in a single core. To relate the variables to the outcome of stage >pT2 (stage pT2+ was excluded) we used logistic regression; to PSA progression the Cox model; and, to time of biochemical failure the Kaplan-Meier curves. Two-sided P-values of <0.05 were considered.
Results: All methods of measurement significantly predicted stage >pT2. Percentage of cancer in all cores had the strongest prediction. On multivariate analysis, this method had a gain in prediction when associated either to preoperative PSA, Gleason grade in the biopsy or both. With the exception of the greatest length and the greatest percentage of cancer in a single core, the other methods significantly were associated with PSA biochemical failure. Percentage of cancer in all cores had again the strongest prediction but no gain was found when associated to preoperative PSA, Gleason grade in the biopsy or both. Time of PSA progression was significantly related to percentage of positive cores, greatest length of cancer in a single core and length and percentage of extent of cancer in all cores. The latter method had the strongest relation.
Conclusions: All methods for measurement of cancer extent in needle biopsies had positive predictive value for stage >pT2 but not all of them predicted PSA progression. Percentage of linear extent in mm of cancer in all cores had the strongest positive predictive value for stage >pT2 and PSA progression; in association with preopeative PSA and Gleason grade may improve the predictive value of stage >pT2 of the available presurgical nomograms.
Category: Genitourinary (including renal tumors)

Tuesday, March 23, 2010 1:00 PM

Poster Session IV # 112, Tuesday Afternoon

 

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