Predictive factors and oncological outcomes of persistently elevated prostate-specific antigen in patients following robot-assisted radical prostatectomy

Impact of persistent PSA after salvage radical prostatectomy: a multicenter study

BACKGROUND AND OBJECTIVE

Persistent prostatic specific antigen (PSA) represents a poor prognostic factor for recurrence after radical prostatectomy (RP). However, the impact of persistent PSA on oncologic outcomes in patients undergoing salvage RP is unknown. To investigate the impact of persistent PSA after salvage RP on long-term oncologic outcomes.

MATERIAL AND METHODS

Patients who underwent salvage RP for recurrent prostate cancer between 2000 and 2021 were identified from twelve high-volume centers. Only patients with available PSA after salvage RP were included. Kaplan-Meier analyses and multivariable Cox regression models were used to test the effect of persistent PSA on biochemical recurrence (BCR), metastasis and any death after salvage RP. Persistent PSA was defined as a PSA-value ≥ 0.1 ng/ml, at first PSA-measurement after salvage RP.

RESULTS

Overall, 580 patients were identified. Of those, 42% (n = 242) harbored persistent PSA. Median follow-up after salvage RP was 38 months, median time to salvage RP was 64 months and median time to first PSA after salvage RP was 2.2 months. At 84 months after salvage RP, BCR-free, metastasis-free, and overall survival was 6.6 vs. 59%, 71 vs. 88% and 77 vs. 94% for patients with persistent vs. undetectable PSA after salvage RP (all p < 0.01). In multivariable Cox models persistent PSA was an independent predictor for BCR (HR: 5.47, p < 0.001) and death (HR: 3.07, p < 0.01).

CONCLUSION

Persistent PSA is common after salvage RP and represents an independent predictor for worse oncologic outcomes. Patients undergoing salvage RP should be closely monitored after surgery to identify those with persistent PSA.

Decipher Score predicts prostate specific antigen persistence after prostatectomy

BACKGROUND

The aim of this study was to evaluate genomic risk of patients with persistent prostate specific antigen (PSA) using mRNA expression analysis and a validated prognostic genomic-risk classifier.

METHODS

Monocentric retrospective study including all patients who underwent radical prostatectomy (RP) by one surgeon and Decipher Test from October 2013 to December 2018. PSA persistent population was defined as all patients with two consecutive PSA>0.1 ng/mL at follow-up after the surgery. Neurovascular Structure-adjacent Frozen-section Examination (NeuroSAFE) was performed intraoperatively for research of positive surgical margins. Multivariate analysis was performed for persistent PSA (pPSA) predictors. A specific localized, organ-confined, and negative margins sub-population with PSA persistence was compared to a similar sub-population without PSA persistence for genomic differential expression analyses.

RESULTS

A total of 564 patients were included and 61 of them had pPSA. Preoperative PSA was higher in the PSA persistent group (11.6 [6.4, 21.2] vs. 6.2 [4.7, 9.2] P=0.00010), as well as PSA density (PSAd) (0.3 [0.2, 0.5] vs. 0.2 [0.1, 0.3] P=0.0001). Postoperative characteristics, Gleason Score, and positive surgical margins were significantly higher in the PSA persistent population. 31 patients had pPSA in our specific subpopulation and were compared to 217 patients with no pPSA. On multivariate analysis, only Decipher Score (OR=5.64 [1.28; 24.89], P=0.022) and preoperative PSA (OR=1.06, [1.02; 1.09], P=0.001) were significant predictors for PSA persistence. We found two genes to be significantly upregulated with a 2.5-fold change in our specific subpopulation (SERPINB11 and PDE11A).

CONCLUSIONS

We found unique genomic features of patients with pPSA, whilst confirming previous clinical findings that this condition behaves to a worse prognosis. Given this high genomic risk, further imaging studies should be performed to select patients for early treatment intensification.

The Impact of the Percent of Residual Prostate-Specific Antigen on Metastasis-Free Survival in Patients with Persistent Prostate-Specific Antigen after Radical Prostatectomy

PURPOSE

Persistent levels of prostate-specific antigen (PSA) is a poor prognostic factor for recurrence after radical prostatectomy (RP). We investigated the impact of the percentage of residual PSA (%rPSA) [(post-/preoperative PSA)×100], representing a biochemical residual tumor, and the first postoperative PSA (fPSA) level on metastasis-free survival (MFS) in men with persistent levels of PSA after RP.

MATERIALS AND METHODS

We retrospectively identified male patients within a single tertiary referral hospital database who harbored persistent (≥0.1 ng/mL) vs. undetectable (<0.1 ng/mL) PSA levels 4 to 8 weeks after RP. Kaplan-Meier analyses and Cox regression models were used to test the effect of persistent PSA levels, the fPSA level, and %rPSA on MFS.

RESULTS

Of 1,205 patients, 178 patients with persistent PSA levels were enrolled. Seven-year MFS rates were 60.5% vs. 84.3% (p<0.001) for patients with a %rPSA ≥6% and <6%, respectively. Multivariable Cox regression models of the overall cohort revealed that persistent PSA levels (hazard ratio [HR], 3.94; p=0.010), extracapsular extension (HR, 4.17; 95% confidence interval [CI], 1.06-16.41; p=0.041), and pathological Gleason grade group (pGGG) (HR, 3.69; 95% CI, 1.32-10.27; p=0.013) were independent predictors of metastasis. Multivariable Cox regression models in men with persistent PSA levels revealed that the %rPSA (HR, 8.92; 95% CI, 1.74-45.71; p=0.009) and pGGG 4-5 (HR, 4.13; 95% CI, 1.22-13.96; p=0.022) were independent predictors of distant metastasis, but not the fPSA level after surgery.

CONCLUSIONS

Persistent levels of PSA were associated with worse MFS after RP. In men with persistent PSA levels after RP, the %rPSA is a valuable predictor of MFS unlike the fPSA level.

Short-term oncological and surgical outcomes of robot-assisted radical prostatectomy: A retrospective multicenter cohort study in Japan (the MSUG94 group)

INTRODUCTION

We evaluated oncological outcomes of patients undergoing robot-assisted radical prostatectomy (RARP) for prostate cancer (PCa) and their perioperative complications in Japan. We investigated clinical and pathological covariates to predict biochemical recurrence (BCR) after RARP.

METHODS

A retrospective multicenter cohort study was conducted in RARP patients with PCa at 10 institutions in Japan. Pre- and postoperative covariates were collected from enrolled patients. The primary endpoint was defined as biochemical recurrence-free survival (BRFS). Additionally, the association between BCR and clinicopathological covariates was determined.

RESULTS

We enrolled 2670 patients in this study. The median follow-up period was 26.0 months. RARP-related perioperative complications were identified in 198 patients (7.4%), including 69 patients (2.6%) with grade 3/4 complications according to the Clavien-Dindo classification. The 2-year BRFS was 88.0%. Using the Kaplan-Meier method, initial prostate-specific antigen (PSA) level of ≤7.6 ng/mL, biopsy and pathological Gleason score (GS) of ≤7, clinical and pathological T1/2, and low/intermediate risks according to the National Comprehensive Cancer Network risk classification, and negative surgical margin status had significant BRFS than their counterparts. In multivariate analysis, initial PSA, biopsy and pathological GS, clinical and pathological T stage, and surgical margin status significantly correlated with BCR after RARP.

CONCLUSION

In this study, RARP achieved a lower incidence of perioperative complications than other studies.

Clinicopathological and oncological significance of persistent prostate-specific antigen after radical prostatectomy: A systematic review and meta-analysis

Objective

To investigate the association of persistently elevated prostate-specific antigen (PSA) after radical prostatectomy (RP) with clinicopathological features and long-term oncological prognosis for the development of a potential management strategy.

Methods

A systematic literature search was performed using PubMed and Web of Science up to June 2021 to identify the eligible studies focusing on understanding the impact of persistent PSA in patients who underwent RP for localized prostate cancer. Meta-analyses were performed on parameters with available information.

Results

A total of 32 RP studies were identified, of which 11 included 26 719 patients with consecutive cohorts and the remaining 21 comprised 24 177 patients with cohorts carrying specific restrictions. Of the 11 studies with consecutive cohorts, the incidence of persistent PSA varied between 3.1% and 34.6% with a median of 11.0%. Meta-analyses revealed patients with persistent PSA consistently showed unfavorable clinicopathological features and a more than 3.5-fold risk of poorer biochemical recurrence, metastasis, and prostate cancer-specific mortality prognosis independently, when compared to patients with undetectable PSA. Similarly, cases with persistent PSA in different specific patient cohorts with a higher risk of prostate cancer also showed a trend of worse outcomes.

Conclusion

We found that the frequency of persistent PSA was about 11.0% in consecutive RP cohorts. Persistent PSA was significantly associated with unfavorable clinicopathological characteristics and worse oncological outcomes. Patients with persistent PSA after RP may benefit from early salvage treatment to delay or prevent biochemical recurrence, improving oncological outcomes for these patients. Further prospective randomized controlled trials are warranted to understand optimal systemic therapy in these patients.

A risk grouping algorithm for predicting factors of persistently elevated prostate-specific antigen in patients following robot-assisted radical prostatectomy

OBJECTIVE

After radical prostatectomy, prostate-specific antigen(PSA) value measuring ≥0.1 ng/mL is defined as persistent PSA(pPSA) and in many studies, it was found to be associated with aggressive disease and poor prognosis. Our aim in this study is to point out the pathological and clinical factors affecting pPSA among the patients who underwent robot-assisted radical prostatectomy(RARP) in an experienced academic centre and to make a useful risk grouping algorithm that can predict pPSA value based on operative data.

METHODS

We examined records of 1273 patients who underwent RARP retrospectively. Preoperative, operative and postoperative data were collected. Based on the PSA values (ng/mL) measured after 4-to-8 weeks of RARP, patients were divided into two groups as pPSA group (Group1)(n = 97) with PSA values ≥0.1 ng/mL and undetectable PSA group (Group2)(n = 778) with PSA values <0.1 ng/mL. Later on, Group1 was further divided into Group1a (PSA:0.1-0.2 ng/mL) and Group 1b (PSA≥0.2 ng/mL) to evaluate biochemical recurrence(BCR).

RESULTS

Multivariate logistic regression analyses of the collected data revealed that preoperative PSA≥20 ng/mL, operation time, a postoperative international society of urological pathology (ISUP) grade of ≥4, pT 3-4 and pN were independently associated with pPSA. Based on these results, a risk grouping algorithm predicting pPSA was developed. By looking at the risk grouping algorithm pPSA was found in 98.9% of the cases with a preoperative PSA value of ≥20 ng/mL, an operation time of 150 min, a postoperative ISUP grade of 4-5, a positive lymphovascular invasion (LVI) status, pT3-T4, and pN+; while pPSA was found in 25.5% of the cases with a preoperative PSA value of <20 ng/mL, an operation time of 100 min, a postoperative ISUP grade of <4-5, a negative LVI status, pT<3-4 and pN-. The estimated BCR-free survival time was 16.3 months in Group 1a and 57.0 months in Group2 (P < .001). Adjuvant treatment ratio was 64.9% in Group1 and 7.1% in Group2 (P < .001).

CONCLUSION

For the patients who underwent RARP, factors associated with aggressive disease can predict the PSA persistence. To plan our treatment modalities accurately, an applicable risk grouping algorithm in daily practice would be useful.

Benefits of early salvage therapy on oncological outcomes in high-risk prostate cancer with persistent PSA after radical prostatectomy

BACKGROUND

Patients with prostate-specific antigen (PSA) persistence are at the increased risk of disease progression. The aim of our study was to evaluate the impact of early salvage therapy on oncological outcomes in patients with persistent PSA after radical prostatectomy (RP).

METHODS

Within a single tertiary centre database, we identified men with persistent (≥ 0.1 ng/ml) versus undetectable (< 0.1 ng/ml) PSA 4-8 weeks after RP for high-risk prostate cancer (HRPCa). The cumulative incidence function was used to estimate cancer-specific survival (CSS) and clinical progression-free survival (CPFS). The Kaplan-Meier method was used to estimate overall survival (OS). The effects on oncological outcomes of salvage radiotherapy (SRT) ± androgen deprivation therapy (ADT) vs. ADT monotherapy were tested in the subgroup of patients with persistent PSA.

RESULTS

Of 414 consecutive patients who underwent RP for HRPC, 125 (30.2%) had persistent PSA. Estimated 10-year CPFS, CSS and OS for men with persistent vs. undetectable PSA were 63.8% vs. 93.5%, 78.5% vs. 98.3% and 54% vs. 83.2% (all p < 0.0001), respectively. In men with persistent PSA, ADT alone was associated with higher risk (hazard ratio (HR) for worse CSS (HR 3.9, p = 0.005) and OS (HR 4.7, p < 0.0001) but not for CP (HR 1.6, p = 0.2) when compared with SRT ± ADT.

CONCLUSION

In patients who underwent RP for HRPCa, persistent PSA was associated with poor oncological outcomes. Early SRT ± ADT resulted in significantly improved CSS and OS in men with persistent PSA comparing with early androgen deprivation monotherapy.

The Significance of Prostate Specific Antigen Persistence in Prostate Cancer Risk Groups on Long-Term Oncological Outcomes

Simple Summary

The current prostate cancer guidelines recommend performing the first prostate-specific antigen measurement at three months after radical prostatectomy. However, at an earlier measurement, persistence (≥0.1 ng/mL) of this biomarker could be found in up to 30% of cases, depending on the prostate cancer risk factors. Recent reports have demonstrated an increasing interest in prostate-specific antigen persistence as a possible additional predictor of disease progression and cancer-specific survival. However, the data remain scant, with weak evidence. We assessed the relationship between prostate-specific antigen persistence and long-term oncological outcomes within prostate cancer risk groups. We found that persistence of this biomarker could be used as an independent predictor of worse long-term outcomes in high-risk prostate cancer patients, while in intermediate-risk patients, this parameter significantly predicts only biochemical recurrence and has no impact on the outcomes in low-risk patients.

Abstract

Objective: To assess the significance of prostate-specific antigen (PSA) persistence at the first measurement after radical prostatectomy (RP) on long-term outcomes in different prostate cancer risk groups. Methods: Persistent PSA was defined as ≥0.1 ng/mL at 4–8 weeks after RP. Patients were stratified into low-, intermediate- and high-risk groups, according to the preoperative PSA, pathological stage, grade group and lymph nodes status. The ten-year cumulative incidence of biochemical recurrence (BCR), metastases, cancer-specific mortality (CSM) and overall mortality (OM) were calculated in patients with undetectable and persistent PSA in different PCa-risk groups. Multivariate regression analyses depicted the significance of PSA persistence on each study endpoint. Results: Of all 1225 men, in 246 (20.1%), PSA persistence was detected. These men had an increased risk of BCR (hazard ratio (HR) 4.2, p < 0.0001), metastases (HR: 2.7, p = 0.002), CRM (HR: 5.5, p = 0.002) and OM (HR: 1.8, p = 0.01) compared to the men with undetectable PSA. The same significance of PSA persistence on each study endpoint was found in the high-risk group (HR: 2.5 to 6.2, p = 0.02 to p < 0.0001). In the intermediate-risk group, PSA persistence was found as a predictor of BCR (HR: 3.9, p < 0.0001), while, in the low-risk group, PSA persistence was not detected as a significant predictor of outcomes after RP. Conclusions: Persistent PSA could be used as an independent predictor of worse long-term outcomes in high-risk PCa patients, while, in intermediate-risk patients, this parameter significantly predicts only biochemical recurrence and has no impact on the outcomes in low-risk PCa patients.

Management of Persistently Elevated Prostate-specific Antigen After Radical Prostatectomy: A Systematic Review of the Literature

CONTEXT

The prognosis and optimal management of pN0/pN1 patients with persistently elevated prostate-specific antigen (PSA) 6-8 wk after radical prostatectomy (RP) remain unclear.

OBJECTIVE

To perform a systematic review of oncologic outcomes and effectiveness of salvage therapies in men with a detectable PSA level after RP.

EVIDENCE ACQUISITION

A systematic review was performed in May 2020. A total of 2374 articles were screened, and 25 studies including 5217 men were selected and included in the systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.

EVIDENCE SYNTHESIS

PSA persistence was most commonly defined as PSA >0.1 ng/ml. PSA persistence was significantly correlated with disease aggressiveness and associated with worse oncologic outcomes than in men with undetectable PSA levels. The 5-yr recurrence-free survival rates varied from 21.5% to 67.0%. The ≥10-yr cancer-specific survival was 75-88%. Salvage radiotherapy ± androgen deprivation therapy was associated with improved survival outcomes. Risk stratification according to pathologic features, PSA levels/kinetics, and genomic classifier may aid in personalization of treatment. The usefulness of molecular imaging in this setting remains underevaluated. Main limitations of this systematic review are the retrospective design of the included studies and the lack of randomized controlled trials (RCTs) focusing on this specific population.

CONCLUSIONS

PSA persistence after RP is strongly correlated with poor oncologic outcomes. Our review suggests a benefit from immediate radiotherapy; however, current evidence is still low. Indication of subsequent therapies should be based on individual discussions, taking into account all the prognostic factors and the efficacy/toxicity imbalance of proposed treatment. Results from ongoing RCTs are awaited to state on the role of more intensified systemic therapy in this population.

PATIENT SUMMARY

Patients with a detectable prostate-specific antigen level after surgery are at high risk of subsequent progression. Immediate radiotherapy might improve survival outcomes. Further research into the role of molecular imaging and genomic classifier is needed in this patient population.

Factors affecting biochemical recurrence of prostate cancer after radical prostatectomy in patients with positive and negative surgical margin

Purpose

To investigate the clinical and pathological predictive factors affecting biochemical recurrence (BCR) after radical prostatectomy (RP) in patients with positive and negative surgical margin (SM).

Methods

Patients who underwent RP were retrospectively reviewed for the study. Demographic, clinical, pathological and oncological data were evaluated. All data were compared between patients with positive SM and negative SM to detect factors associated with SM status. Later, patients were divided into two groups as BCR-negative and BCR-positive groups. Data were separately compared between BCR groups for all patients, SM-negative and SM-positive patients, respectively.

Results

A total of 254 patients with a mean age of 63.5 years and the mean prostate-specific antigen of 10.9 ng/ml were evaluated in the study. SM positivity was found to be an independent prognostic factor for BCR (p = 0.013, Odds Ratio (OR): 0.267, 95% Confidence Interval (CI): 0.094-0.755). In SM-positive patients, biopsy Gleason Score and International Society of Urological Pathology grade were found to be independent predictive factors for BCR (p < 0.05). However, only tumor to SM distance (TSMD) was found to be an independent risk factor for BCR (p = 0.024) in SM-negative patients. The predictive cutoff value of the TSMD was found to be 75 μm for BCR (100% sensitivity and 63.9% specificity) (AUC = 0.803, p = 0.024). Although all of 46 patients with >75 μm TSMD were recurrence free, 5 of 31 patients with <75 μm TSMD had BCR (p = 0.009; OR: 0.839 CI: 0.719-0.979).

Conclusion

High Gleason Score and International Society of Urological Pathology grade of biopsy were found to be associated with BCR in SM-positive patients. For SM-negative patients, only TSMD was found to be associated with BCR after RP.

Undetectable PSA after radical prostatectomy is more likely in low burden N+ prostate cancer patients when an extended lymph node dissection is performed

OBJECTIVES

To analyze the likelihood of undetectable PSA (< 0.01 ng/mL) after extended (ePLND) versus standard pelvic lymph-nodes dissection (sPLND) in pN+ patients.

MATERIALS AND METHODS

The institutional prospectively maintained Prostate Cancer Database was queried for patients who underwent radical prostatectomy with PLND and were found with 3or less lymph-nodal metastases between 2007 and 2017. The extension of the PLND was defined according to the number of lymph-nodes (LN) removed. Patients in the 75th or higher percentile of lymph-nodes removed were considered as the ePLND group; patients in the 25th or lower percentile in the sPLND group. Groups were compared in clinical and pathological variables. Student T-test was used for comparing continuous variables; chi-square test was used for categorical variables. Multivariable logistic regression assessed the probability of undetectable PSA at 3^rd month postoperatively. Kaplan-Meier method estimated the probability of biochemical recurrence. Differences between the groups were compared by Log-rank test.

RESULTS

1478 patients were treated within the time span considered. 95 with 1 to 3 lymph-nodal metastases were extracted. After accounting for inclusion criteria, 23 patients with a median of 11 LN removed were included in the sPLND group (25th percentile); 23 patients with > 27 LN were included in ePLND group (75th percentile). Surgical time was longer for ePLND. Sixteen patients (69.6%) who underwent ePLND had undetectable PSA postoperatively. At multivariable analysis, the probability of undetectable PSA at 3^rd month was higher in patients who received an ePLND (HR=5.18; IC 95%=1.16-23.11; P=.03).

CONCLUSIONS

ePLND is more likely to predict undetectable PSA at third month after radical prostatectomy, irrespective of disease characteristics.

Worth a local treatment? - Analysis of modern radiotherapy concepts for oligometastatic prostate cancer

Background

Prostate cancer (PCA) is the most-prevalent non-skin cancer in men worldwide. Nevertheless, the treatment of oligometastatic, especially lymph-node (ln) recurrent, PCA remains elusive. The aim of our study was to provide insights in radiotherapy (RT)-treatment of recurrent PCA exhibiting ln- or osseous (oss)-oligometastases.

Methods

Between April 2012 and April 2017, 27 oligometastatic PCA patients (19 ln and 8 single oss) were treated with RT at our institution.

Results

The metastasis-free survival (MFS) was 24.8 m (22.0–36.0 m) and 25.4 m (23.9–28.1 m) for the ln- and oss-subgroup resulting in 1-year MFS of 75.4 and 100% and 2-year MFS of 58.7 and 83.3% for ln- and oss-metastatic patients, respectively. Of notice, none of the recurrences for ln-patients was in the RT-field, constituting a local control of 100%.

Within the ln-group, pre-RT median-PSA was 2.6 ng/ml, median post-RT PSA was 0.3 ng/ml, which was significant (p = 0.003). Median biochemical-free survival (bfS) was 12.2 m. PCA that was initially confined to the prostate had a better bfS (p < 0.001) and MFS (p = 0.013). The oss-group had a median PSA of 4.9 ng/ml pre-treatment which dropped to a median value of 0.14 ng/ml (p = 0.004).

Toxicities were moderate, with only 1 case of III° toxicity. There were no deaths in the ln-group, thus overall survial was 100% here.

Conclusion

Our study points out the feasibility of RT as a treatment option in recurrent PCA and demonstrates an excellent local control with a low-toxicity profile.

Positive surgical margin is associated with biochemical recurrence risk following radical prostatectomy: a meta-analysis from high-quality retrospective cohort studies

Background and purpose

Although numerous studies have shown that positive surgical margin (PSM) is linked to biochemical recurrence (BCR) in prostate cancer (PCa), the research results have been inconsistent. This study aimed to explore the association between PSM and BCR in patients with PCa following radical prostatectomy (RP).

Materials and methods

In accordance with the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), PubMed, EMBASE and Wan Fang databases were searched for eligible studies from inception to November 2017. The Newcastle–Ottawa Scale was used to assess the risk of bias of the included studies. Meta-analysis was performed by using Stata 12.0. Combined hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated using random-effects or fixed-effects models.

Results

Ultimately, 41 retrospective cohort studies of high quality that met the eligibility criteria, comprising 37,928 patients (94–3294 per study), were included in this meta-analysis. The results showed that PSM was associated with higher BCR risk in both univariate analysis (pooled HR = 1.56; 95% CI 1.46, 1.66; p < 0.001) and multivariate analysis (pooled HR = 1.35; 95% CI 1.27, 1.43; p < 0.001). Moreover, no potential publication bias was observed among the included studies in univariate analysis (p-Begg = 0.971) and multivariate analysis (p-Begg = 0.401).

Conclusions

Our meta-analysis demonstrated that PSM is associated with a higher risk of BCR in PCa following RP and could serve as an independent prognostic factor in patients with PCa.

Electronic supplementary material

The online version of this article (10.1186/s12957-018-1433-3) contains supplementary material, which is available to authorized users.

Validation of American Joint Committee on Cancer eighth staging system among prostate cancer patients treated with radical prostatectomy

Background

The objective in this paper was to validate the prognostic performance of the American Joint Committee on Cancer (AJCC) 7th and 8th systems among prostate cancer patients treated with radical prostatectomy.

Methods

The surveillance, epidemiology and end results (SEER) database (2006-2014) was accessed through the SEER*Stat program and AJCC 7th and 8th editions were calculated utilizing T, N and M stages, histological grade group, as well as baseline prostatic-specific antigen (PSA). Cancer-specific and overall survival analyses according to 7th and 8th editions were conducted. Moreover, multivariate analysis was conducted through a Cox proportional hazard model.

Results

A total of 72,999 patients with prostate cancer were identified in the period from 2006 to 2014. Overall survival was assessed according to AJCC 7th and 8th staging systems. The test for trend for overall survival was significant (p < 0.0001) for both staging systems. Concordance index for AJCC 7th system was: 0.791 [standard error of the mean (SE): 0.017; 95% CI: 0.758-0.825]; while concordance index for AJCC 8th system was: 0.840 (SE: 0.015; 95% CI: 0.811-0.869). In a multivariate analysis among patients with M0 disease, lower grade group, N0 stage and pT2 stage were associated with better cancer-specific survival (p < 0.01); while PSA level did not predict cancer-specific survival.

Conclusion

There is a clear improvement in the discriminatory ability for AJCC 8th versus AJCC 7th staging system in the postprostatectomy setting. This may be related to better integration of biological factors into the staging system.

Impact of Postoperative Radiotherapy in Men with Persistently Elevated Prostate-specific Antigen After Radical Prostatectomy for Prostate Cancer: A Long-term Survival Analysis

BACKGROUND

Prostate cancer (PCa) patients with prostate-specific antigen (PSA) persistence after radical prostatectomy (RP) are at increased risk of mortality, although the natural history of these men is heterogeneous and the optimal management has not been established.

OBJECTIVE

To develop a model to predict cancer-specific mortality (CSM) and to test the impact of radiotherapy (RT) on survival in this setting.

DESIGN, SETTING, AND PARTICIPANTS

We identified 496 patients treated with RP and lymph node dissection at two referral centers between 1994 and 2014 who had PSA persistence, defined as a PSA level between 0.1 and 2 ng/ml at 6-8 wk after RP.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

A multivariable model predicting CSM was developed. We assessed whether the impact of postoperative PSA levels on survival differed according to baseline CSM risk. The nonparametric curve fitting method was then used to explore the relationship between baseline CSM risk and 10-yr CSM rates according to postoperative RT.

RESULTS AND LIMITATIONS

Median follow-up for survivors was 110 mo. Overall, 49 patients experienced CSM. The 10-yr CSM-free survival was 88%. Pathologic grade group and pathologic stage were independent predictors of CSM (all p=0.01). The association between CSM-free survival and PSA at 6-8 wk differed by the baseline CSM risk, whereby the effect of increasing PSA was evident only in patients with a CSM risk of ≥10%. Postoperative RT was beneficial when the predicted risk of CSM was ≥30% (p=0.001 by an interaction test). Our study is limited by its retrospective design.

CONCLUSIONS

Increasing PSA levels should be considered as predictors of mortality exclusively in men with worse pathologic characteristics. Postoperative RT in this setting was associated with a survival benefit in patients with a CSM risk of ≥30%. Conversely, individuals with a CSM risk of <30% should be initially managed expectantly.

PATIENT SUMMARY

Not all patients with prostate-specific antigen persistence have a poor prognosis. Pathologic characteristics should be used to estimate the risk of cancer-specific mortality in these individuals and to identify patients who could benefit from postoperative radiotherapy.