Introduction

Previously, we developed the postoperative nomogram to predict the non-biochemical recurrence in patients with open and RARP (IJU 21:479, 2014). However, we found the significant differences of pathological and prognostic outcomes between open and RARP (AUA2016 Hirasawa). Therefore, we up-dated and developed the postoperative nomogram to predict the non-biochemical recurrence rate using the Japanese patients treated with RARP.

Methods

A total of 1000 Japanese patients with T1-3N0M0 prostate cancer who underwent RARP and pelvic lymph node dissection at Tokyo Medical University hospital from 2009 to 2015 were studied. Patients with neoadjuvant therapy were excluded. A nomogram was constructed based on Cox hazard regression analysis evaluating the prognostic significance of serum PSA and pathological factors in the RARP specimens. The discriminating ability of the nomogram was assessed by the concordance index (C-index), and the predicted and actual outcomes were compared with a bootstrapped calibration plot_x000D_ .

Results

With a mean follow up of 32.0 months, a total of 145 patients (14.5%) experienced_x000D_ biochemical recurrence with a 5-year non-biochemical recurrence rate of 80.0%. A Cox hazard regression analysis showed that preoperative PSA (p<0.0005), prostatectomy Gleason score (p<0.0005), pathological stage (p=0.001), surgical margins (p<0.0005), and lymphovascular invasion (p=0.0024) were significant factor to predict biochemical recurrence. Based on this analysis, a nomogram was constructed to predict non-biochemical recurrence using PSA level and pathological features in RARP specimens. The concordance index was 0.80, and the calibration plots appeared to be accurate._x000D_

Conclusions

Since RARP became most popular procedure in Japan, our postoperative nomogram can provide valuable information to many patients regarding the need for adjuvant/salvage radiation or hormonal therapy after RARP. To our knowledge, our nomogram may be the first nomogram for the non-Caucasian Asian population who were treated with RARP

Funding

none