Abstract: PD51-07
Sources of Funding: none

Introduction

The impact of the time interval (TI) between prostate biopsy and robot-assisted radical prostatectomy (RARP) on the risk of biochemical recurrence (BCR) has been controversial so far. It is possible that clinicians empirically decide on curative treatments earlier for patients who are expected to have a worse prognosis, resulting in a so-called treatment selection bias. Therefore, we performed propensity score matching analysis to investigate the potential impact of treatment delays in patients with localized prostate cancer._x000D_

Methods

We retrospectively reviewed the medical records of 812 patients who were treated with RARP at our institution. A multivariate Cox analysis was used to identify the independent significant preoperative risk factors for BCR. Using these preoperative risk factors, a propensity score matching analysis was conducted to adjust for the preoperative characteristics between two patient groups: Group A, TI ≤ 6 months; Group B, TI ≥ 6 months). Clinicopathological outcomes and BCRFS between the two groups were compared to investigate the impact of TI ≥ 6 months on oncological outcomes after RARP.

Results

The median follow-up period after RARP was 32.2 months (6.1-104.9 months). The multivariate analysis revealed that PSA, primary (pGS) and secondary (sGS) Gleason score, and a positive prostate biopsy were independent preoperative risk factors for BCR. One hundred and two patients with Group B were matched with an equal number of patients with Group A based on propensity scores by using six preoperative factors: PSA, pGS and sGS, clinical T stage, age, and positive prostate biopsy. The propensity adjusted 5-year BCRFS for patients with TI ≥ 6 months was 85.5%. This was not worse than that of patients with TI ≤ 6 months (85.0%, p = 0.85). Similarly for D&[prime]Amico low-risk patients, the propensity adjusted 5-year BCRFS rates for Group A and Group B were 99.2% and 99.4%, respectively (p = 0.84); for intermediate-risk patients, 89.1% and 79.6%, respectively (p = 0.19); and for high-risk patients, 69.9% and 89.1%, respectively (p = 0.36). There were no significant differences with regards to Gleason upgrading (p = 0.46) or upstaging (p = 0.11) after propensity adjustments between the two groups._x000D_

Conclusions

In our cohorts, a delay in the time from biopsy to RARP did not significantly affect BCR. Therefore, hasty treatment decisions are unnecessary for at least 6 months after biopsy of early prostate cancer. However, we suppose that our results may not be same for patients with very high-risk/locally advanced cancer.

Funding

none