Maximum tumor diameter is not an independent prognostic factor in high-risk localized prostate cancer

OBJECTIVES: Previous studies suggest that maximum tumor diameter (MTD) is a predictor of recurrence in prostate cancer (PC). This study investigates the prognostic value of MTD for biochemical recurrence (BCR) in patients with PC, after radical prostatectomy (RP), with emphasis on high-risk localized prostate cancer. METHODS: RP specimens of 542 patients were evaluated with a median follow-up of 39.5 months (range 0.6–150 months). MTD was defined as the largest diameter of the largest tumor; high-risk as ≥T2c or PSA level > 20 ng/ml or Gleason score ≥8 and BCR as two consecutive PSA levels > 0.10 ng/ml. Proportional hazards multivariable regression models were composed to determine prognostic factors for BCR. RESULTS: Overall, 114 patients developed BCR after RP. The overall 5-year risk of BCR was 25% (95% CI = 20.4–29.6), and median MTD was 24 mm (range 1–65). MTD in the total and high-risk group was associated with total tumor volume, volume of the largest tumor, pre-operative PSA levels, and Gleason score. In a univariable analyses, MTD was weakly associated with risk of BCR (HR = 1.02 per mm increase, 95% CI = 1.002–1.035, P = 0.024) in the total group; in the high-risk group this association was lost (HR = 1.01, 95%CI = 0.99–1.03, P = 0.18). Multivariable analyses indicated that positive surgical margins, higher Gleason score, advanced pathological stage, and multiple tumors were the main prognostic factors for BCR irrespective of the risk profile. MTD did not provide additional information. CONCLUSIONS: MTD is not an independent prognostic factor for BCR in patients treated with RP, irrespective of the risk profile.