Prognostic Value of Tumor Volume in Prostate Cancer
Camilla Hilliges, Fredrik Wiklund, Peter Wiklund, Lars Egevad. Karolinska Institutet, Stockholm, Sweden
Background: Tumor volume of prostate cancer has been shown to correlate with recurrence rate after radical prostatectomy. However, it remains controversial whether it is an independent prognostic factor and if total tumor volume (Vtot) or the volume of the main tumor (V1) is the best predictor of outcome.
Design: Tumor volume was measured on radical prostatectomy specimens from the Karolinska Hospital 1998 - 2002. Men with neoadjuvant treatment or TURP prior to surgery, unavailable clinical follow-up data or histological slides were excluded and 282 cases remained for analysis. All specimens were completely embedded, cancer was outlined with Indian ink and the volumes of the main tumor (V1), secondary tumor foci (V2) and other tumor foci (V3) were measured by computerized planimetry. Vtot was calculated by adding V1, V2 and V3. Cox regression models were used to assess the correlation between clinical and histopathological features and biochemical recurrence.
Results: Mean follow-up time was 60.8 months (range 1-144). Gleason scores (GS) were 5-6 (47.2%), 7 (40.8%) and 8-10 (12.1%). Extraprostatic extension (EPE), positive surgical margins (PSM) and seminal vesicle invasion (SVI) were seen in 47.5%, 46.8% and 12.8%, respectively. Mean Vtot was 2.9 ml (range 0.04-15.3) and mean V1 was 2.4 ml (range 0.02-15.3). Both Vtot (hazard ratio [HR] 1.13, 95% confidence interval [95% CI] 1.07-1.19) and V1 (HR 1.12, 95% CI 1.06-1.18) predicted recurrence free survival in univariate analysis. Recurrence rate in men with Vtot <1, 1-1.9, 2-2.9, 3-3.9 and ≥4 ml was 27.3%, 28.8%, 37.5%, 48.5% and 63.9%, respectively. In multivariate analysis adjusting for preoperative serum PSA, GS, EPE, PSM and SVI only GS (p<0.001) and PSM (p<0.001) remained independent predictors of recurrence.
Conclusions: Total tumor volume of prostate cancer and volume of the main tumor both predict biochemical recurrence rate in univariate analysis but not in multivariate analysis including preoperative serum PSA and other histopathological prognostic factors. Postoperative measurement of tumor volume is a time-consuming procedure that is unnecessary in routine practice.
Category: Genitourinary (including renal tumors)
Wednesday, March 21, 2012 1:00 PM
Poster Session VI # 166, Wednesday Afternoon