Defining pathological variables to predict biochemical failure in patients with positive surgical margins at radical prostatectomy: implications for adjuvant radiotherapy

The impact of positive surgical margin parameters and pathological stage on biochemical recurrence after radical prostatectomy: A systematic review and meta-analysis

BACKGROUND

To systematically review and perform a meta-analysis on the predictive value of the primary Gleason grade (PGG) at the positive surgical margin (PSM), length of PSM, number of PSMs, and pathological stage of the primary tumor on biochemical recurrence (BCR) in patients with prostate cancer (PCa) after radical prostatectomy (RP).

METHODS

A systematic literature search was performed using electronic databases, including PubMed, EMBASE, Cochrane Library, and Web of Science, from January 1, 2005, to October 1, 2023. The protocol was pre-registered in PROSPERO. Subgroup analyses were performed according to the different treatments and study outcomes. Pooled hazard ratios with 95% confidence intervals were extracted from multivariate analyses, and a fixed or random effect model was used to pool the estimates. Subgroup analyses were performed to explore the reasons for the heterogeneity.

RESULTS

Thirty-one studies that included 50,028 patients with PCa were eligible for this meta-analysis. The results showed that, compared to PGG3, PGG4/5 was associated with a significantly increased risk of BCR. Compared with PSM ≤3 mm, PSM ≥3 mm was associated with a significantly increased risk of BCR. Compared with unifocal PSM, multifocal PSM (mF-PSM) was associated with a significantly increased risk of BCR. In addition, pT >2 was associated with a significantly increased risk of BCR compared to pT2. Notably, the findings were found to be reliable based on the sensitivity and subgroup analyses.

CONCLUSIONS

PGG at the PSM, length of PSM, number of PSMs, and pathological stage of the primary tumor in patients with PCa were found to be associated with a significantly increased risk of BCR. Thus, patients with these factors should be treated differently in terms of receiving adjunct treatment and more frequent monitoring. Large-scale, well-designed prospective studies with longer follow-up periods are needed to validate the efficacy of these risk factors and their effects on patient responses to adjuvant and salvage therapies and other oncological outcomes.

Impact of Gleason score of the tumor at the positive surgical margin as a prognostic factor

Although numerous studies have reported that a positive surgical margin (PSM) is the most important predictive factor for biochemical recurrence (BCR) of prostate cancer (PCa), only a small number of studies have evaluated the predictive value of the Gleason score (GS) of the tumor at the margin in radical prostatectomy (RP). The present study aimed to investigate the preoperative factors that predict PSM and the significant predictive factors for BCR in cases with PSM. In addition, it was examined whether documenting the GS of the tumor at the margin in pathological reports is useful as a predictive factor for BCR. Data of 241 patients with PCa who underwent RP at Kurume University Hospital (Kurume, Japan) between January 2007 and December 2011 were retrospectively reviewed. The median follow-up period was 72 months and 122 patients had at least one PSM. The time to BCR was significantly shorter in patients with PSM than in those with a negative surgical margin. Multivariate analysis demonstrated that >10 ng/ml prostate-specific antigen at diagnosis (P=0.024) and >25% positive core at biopsy (P=0.041) were independent prognostic preoperative factors for PSM. The GS of the tumor at the margin was equal, lower and higher than those of the main tumor in 74 (60.7%), 16 (13.1%) and 32 (26.2%) RPs, respectively. The BCR rates were 35.7, 55.1 and 82.1% in patients whose GS of the tumor at the margin was 6, 7 and 8-10, respectively (P=0.0017). The GS of the tumor at the PSM (P=0.038) and anatomic location of the PSM (P=0.04) were identified as independent prognostic preoperative factors for BCR, whereas the GS of the main tumor and margin length were not. These results suggest that documenting the GS at the margin in pathological reports is useful as a predictive factor for BCR.

Impact of Multifocality and Multilocation of Positive Surgical Margin After Radical Prostatectomy on Predicting Oncological Outcome

OBJECTIVE

To assess the impact of focality and location of positive surgical margins (PSM) on long-term outcomes after radical prostatectomy (RP) for prostate cancer (PCa), including biochemical recurrence (BCR), metastasis and overall mortality.

PATIENTS AND METHODS

From a total of 2796 cases of RP between 1993 and 2007 in our single hospital, 476 cases with PSMs were identified and included in this study. PSM location was categorized into apex, peripheral, and bladder neck. Survival was estimated using the Kaplan-Meier method. Cox proportional hazard regression models were used to analyze the impact of PSM focality and location status on oncologic survival.

RESULTS

Of these 476 cases with PSMs, 335 (70.4%) cases were with single focal (sF) PSMs and 141 (29.6%) cases were with multifocal (mF) PSMs. Furthermore, 406 (85.3%) cases were found to have single location (sL) PSMs, and 70 (14.7%) cases were with multilocation (mL) PSMs. The median follow-up was 12.9 years. mF-PSMs and mL-PSMs showed significant impact on increased BCR risk on univariate analysis, and mL-PSMs remained significant on multivariate analysis (P = .048). Furthermore, the combination of multifocality and multilocation showed added prognostic value on predicting BCR-free survival, but not on metastasis-free survival or overall survival.

CONCLUSION

The presence of mF-PSMs and mL-PSMs, and especially the combination of both, demonstrated significant impact on BCR prognosis. Patients with apex sLsF-PSMs were less likely to have BCR when compared with all those with non-apex sLsF-PSMs. These results should be considered when evaluating patients for adjuvant therapy.

Tumor Volume and Clinical Failure in High-Risk Prostate Cancer Patients Treated With Radical Prostatectomy

INTRODUCTION

To identify the most significant cut-off of tumor volume (TV) for prediction of clinical failure (CF) among high-risk prostate cancer (hPCa) patients.

METHODS

Within a multi-institutional cohort, 262 patients treated with radical prostatectomy (RP) for hPCa were identified. CF was defined as local recurrence or distant metastases. A time dependent ROC curve was used to evaluate the area under the curve (AUC) using TV as single marker to predict clinical failure at 10 years. We searched for the TV cut off value with the highest combined sensitivity and specificity predicting CF. Three multivariable Cox regression analyses (MVA) tested the predictors of CF after RP. Predictors of the model 1 were pre-operative PSA, pathologic stage (PT), pathologic Gleason sum (GS), surgical margin status, and lymph node invasion. Predictors of the models 2 and 3 were the same of model 1 plus TV as a continuous or dichotomous variable using the defined cutoff, respectively. Validation (leave-one-out-cross-validation-LOOCV) of each model was performed.

RESULTS

Overall, 46 (17.6%) patients experienced CF. The TV value was 6.29 ml. In MVA of models 2 and 3, PT and GS remained independent predictors of CF. Moreover, in model 2 TV (HR:1.07,) and in model 3 TV >6.29 ml (HR:2.99,) were independently associated with CF. In LOOCV, the C-index of models 1-3 were 65.53%, 71.75%, and 70.26%, respectively.

CONCLUSIONS

TV is an independent predictor of CF in hPCa patients. Patients with a TV exceeding the cut-off of 6.29 ml are more likely to develop CF. Prostate 77:3-9, 2017. © 2016 Wiley Periodicals, Inc.

Loss of AZGP1 as a Superior Predictor of Relapse in Margin-Positive Localized Prostate Cancer

BACKGROUND

Positive surgical margins (PSMs) in localized prostate cancer (PC) confer a two- to three-fold increased risk of biochemical relapse (BR). Absent/weak AZGP1 expression and Gleason grade ≥4 at the margin are each independent predictors of BR in patients with PSMs. Our study aimed to determine whether the biomarkers AZGP1 expression and Gleason grade at the site of a PSM are significant independent markers of biochemical and clinical relapse (CR) when modeled together and whether one of these biomarkers may be superior in its capacity to predict outcome.

METHODS

A cohort of 275 consecutive patients with margin-positive localized PC following surgery were assessed for Gleason grade and AZGP1 expression at the PSM. BR-free survival was the primary end-point, while CR-free survival and PC-specific death were secondary endpoints. Kaplan-Meier Analysis and Cox Proportional Hazards Modeling were performed.

RESULTS

Absent AZGP1 expression was significantly associated with increased risk of BR (P = 0.001) and PC-specific death (P = 0.02). Gleason grade ≥4 at PSM was associated with BR (P = 0.02), CR (P = 0.003), and PC-specific death (P = 0.004). On multivariable analysis, absent AZGP1 expression remained an independent predictor of BR (HR 2.4, 95%CI 1.5-3.9, P < 0.001) when modeled with Gleason grade at margin (HR 1.3, 95%CI 0.9-1.9, P = 0.16), preoperative PSA (P = 0.002), seminal vesicle involvement (P = 0.002), extraprostatic extension (P = 0.001), Gleason score (P = 0.01), adjuvant treatment (P = 0.75), linear length of the involved margin (P = 0.001) and margin number (P = 0.09).

CONCLUSION

Absent AZGP1 expression is an independent predictor of BR in margin-positive localized PC and is associated with increased PC-specific mortality in a Phase II study. Absent AZGP1 expression was superior to Gleason grade at PSM in predicting relapse and should be incorporated into subsequent clinical trials of post-operative radiotherapy in men with margin-positive PC. Prostate 76:1491-1500, 2016. © 2016 Wiley Periodicals, Inc.

[RETROSPECTIVE ANALYSIS OF POSITIVE SURGICAL MARGIN AT RADICAL PROSTATECTOMY]

We retrospectively reviewed 182 patients who underwent radical prostatectomy in our hospital between April, 2009 to December, 2012, and who had not received any prior hormonal therapy. We also excluded the patients who couldn't followed up more than 6 months after surgery and pN1 patients. Positive surgical margins were observed in 65 cases. We determined what were the significant factors associated with the margin status. The another aim of present study is to evaluate the risk factor which might have significance for biochemical recurrence. BMI ≥ 25.0, prostate volume < 40 cm3, and biopsy positive core ≥ 25% were significant predictors of positive surgical margin. PSA nadir ≥ 0.02 ng/ml and pT3 were the significant factors which associated with biochemical recurrence of those patients with positive margin status.

[Prostate cancer surgical margin: review by the CCAFU (Oncology Committee of the French Association of Urology)]

OBJECTIVE

Literature showed the impact of surgical margin status on prognosis after radical prostatectomy (mostly on biochemical survival). Margin status is an easy self-evaluation of surgical practice to assess. The aim of this paper was to define what a positive surgical margin (PSM) is and how to prevent the occurrence, to precise the impact on survival and how to treat.

METHOD

A literature analysis with Pubmed has been performed to 2012, furthermore conclusions of the main congresses with selection committee and review publication have also been studied.

RESULTS

PSM is defined as "tumor cells touching the ink on the specimen edge". The most frequent reported incidence is between 15 to 20%. Margin status remains one of the major criteria to determine the need of adjuvant radiotherapy after surgery. Quality of life is not or only lightly modified by radiotherapy with the current techniques. Adjuvant radiotherapy improves biological survival but is synonymous with overtreatment in many times. Salvage radiotherapy has to be quickly performed after Prostate Specific Antigen (PSA) relapse (PSA<1 ng/mL even<0.5 ng/mL).

CONCLUSION

This literature review did not allow to suggest superiority of one surgical technique over another. In the same way, the kind of dissection i.e. bladder neck or neurovascular bundle preservation does no clearly modify PSM rate. However, it seems logical to "customize" dissection according to prostate cancer characteristics (D'Amico criteria for instance) guided with multiparametric MRI. Intrafascial dissection has to be applied only to low risk. Lastly, the debate between adjuvant or salvage radiotherapy is always ongoing.

Influence of focal and diffuse extraprostatic extension and positive surgical margins on biochemical progression following radical prostatectomy

PURPOSE

The amount of extraprostatic extension and positive surgical margin correlates in most studies with biochemical recurrence following radical prostatectomy. We studied the influence of focal and diffuse extraprostatic extension and positive surgical margins on biochemical progression using a simple method for quantification.

MATERIALS AND METHODS

A total of 360 prostates were step-sectioned and totally processed from 175 patients with stage T1c and 185 patients with clinical stage T2 submitted to radical retropubic prostatectomy. Extraprostatic extension was stratified into 2 groups: present up to 1 quadrant and/or section from the bladder neck or apex (Group 1, focal) and in more than 1 quadrant or section (Group 2, diffuse); and, positive surgical margin present up to 2 quadrants and/or sections (Group 1, focal) and in more than 2 quadrants or sections (Group 2, diffuse). The Kaplan-Meier product-limit analysis was used for the time to biochemical recurrence, and an univariate and multivariate Cox stepwise logistic regression model to identify significant predictors.

RESULTS

Extraprostatic extension was found in 129/360 (35.8%) patients, 39/129 (30.2%) in Group 1 and 90/129 (69.8%) in Group 2. In univariate analysis but not in multivariate analysis, patients showing diffuse extraprostatic extension (Group 2) had a significant higher risk to develop biochemical recurrence in a shorter time. Positive surgical margin was present in 160/360 (44.4%) patients, 81/160 (50.6%) patients in Group 1 and 79/160 (49.4%) patients in Group 2. Patients with diffuse positive surgical margins (Group 2) had a significant higher risk in both univariate and multivariate analyses. Diffuse positive surgical margin was the strongest predictor on both analyses and an independent predictor on multivariate analysis.

CONCLUSION

Diffuse extraprostatic extension in univariate analysis and positive surgical margins on both univariate and multivariate analyses are significant predictors of shorter time to biochemical progression following radical prostatectomy.

Impact of surgical margin status on prostate-cancer-specific mortality

Study Type--Diagnostic (exploratory cohort) Level of Evidence 2b. What's known on the subject? and What does the study add? Surgical margin status at radical prostatectomy (RP) has been shown to be a predictor of disease progression and the strongest predictor of benefit from adjuvant therapy, but the impact of a positive surgical margin (PSM) on long-term prostate-cancer-specific survival is unknown. The PSM rate is dependent on the pathological stage of the cancer. In a recent multicentre nomogram for 15-year prostate-cancer-specific mortality (PCSM) after RP, PSM was not significantly associated with PCSM, while Gleason score and pathological stage were the only significant predictors. This has not been validated in a single centre, and PSM has been shown to vary greatly with surgical technique. This is the first study on the impact of PSM on PCSM in a single surgeon's cohort. In other centres, the decision to administer adjuvant therapy may be influenced by surgical margin status. In this cohort, men routinely did not receive adjuvant therapy, affording the unique opportunity to study the long-term implications of a PSM.

OBJECTIVE

• To examine the relative impact of a positive surgical margin (PSM) and other clinicopathological variables on prostate-cancer-specific mortality (PCSM) in a large retrospective cohort of patients undergoing radical prostatectomy (RP).

PATIENTS AND METHODS

• Between 1982 and 2011, 4569 men underwent RP performed by a single surgeon. • Of the patient population, 4461 (97.6%) met all the inclusion criteria. • The median (range) age was 58 (33-75) years and the median prostate-specific antigen (PSA) was 5.4 ng/mL; RP Gleason score was ≤ 6 in 2834 (63.7%), 7 in 1351 (30.3%), and 8-10 in 260 (6.0%) patients; PSMs were found in 462 (10.4%) patients. • Cox proportional hazards models were used to determine the impact of a PSM on PCSM.

RESULTS

• At a median (range) follow-up of 10 years (1-29), 187 men (4.3%) had died from prostate cancer. • The 20-year prostate-cancer-specific survival rate was 75% for those with a PSM and 93% for those without. • Compared with those with a negative surgical margin, men with a PSM were more likely to be older (median age 60 vs 58 years) and to have undergone RP in the pre-PSA era (36.6% vs 11.8%). Additionally, they were more likely to have a higher PSA level (median 7.6 vs 5.2 ng/mL), a Gleason score of ≥ 7 (58.7% vs 33.7%), and a non-organ-confined tumour (90.9% vs 30.6% [P < 0.001 for all]). • In a univariate model for PCSM, PSM was highly significant (hazard ratio [HR] 5.0, 95% confidence interval [CI] 3.7-6.7, P < 0.001). • In a multivariable model, adjusting for pathological variables and RP year, PSM remained an independent predictor of PCSM (HR 1.4, 95% CI 1.0-1.9, P = 0.036) with a modest effect relative to RP Gleason score (HR 5.7-12.6) and pathological stage (HR 2.2-11.0 [P < 0.001]).

CONCLUSION

• Although a PSM has a statistically significant adverse effect on prostate-cancer-specific survival in multivariable analysis, Gleason grade and pathological stage were stronger predictors.

Low AZGP1 expression predicts for recurrence in margin-positive, localized prostate cancer

BACKGROUND

Men with positive margins after radical prostatectomy (RP) for localized prostate cancer (PC) have a 40-50% biochemical relapse rate at 5 years. Adjuvant radiotherapy improves biochemical progression-free and overall survival in men with positive margins, but is associated with increased toxicity. There is an urgent need to identify new prognostic markers to define the group of patients who would benefit from multimodality therapy.

METHODS

Nuclear β-catenin, membranous secreted frizzled-related protein 4 (sFRP4), zinc-alpha 2-glycoprotein (AZGP1), and macrophage inhibitory cytokine-1 (MIC-1) have previously been identified as molecular markers of outcome in localized PC. From these published studies, we identified a subset of patients with positive margins. The aim of this study was to assess the association between these four molecular markers and outcome in men with margin-positive, localized PC.

RESULTS

We identified 186 men with positive margins from 330 men with localized PC; 53% had preoperative PSA >10 ng/ml, 72% extraprostatic extension (EPE), 24% seminal vesicles involvement (SVI), and 57% RP Gleason score ≥ 7. AZGP1 (P = 0.009), membranous sFRP4 (P = 0.03) and MIC-1 (P = 0.04) expression predicted for biochemical relapse on univariate analysis. Only absent/low AZGP1 expression (P = 0.01) was an independent predictor of recurrence in margin-positive, localized PC when modeled with preoperative PSA (P = 0.2), EPE (P = 0.2), SVI (P = 0.4), Gleason score ≥ 7 (P = 0.5) and adjuvant treatment (P = 0.4). Furthermore, there was an association between absent/low AZGP1 expression and clinical recurrence (P = 0.007).

CONCLUSIONS

AZGP1 is a potential molecular marker for biochemical relapse in men with margin-positive, localized PC. Routine assessment of this biomarker may lead to better selection of patients who will benefit from post-RP radiotherapy.

High Gleason grade carcinoma at a positive surgical margin predicts biochemical failure after radical prostatectomy and may guide adjuvant radiotherapy

Study Type - Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Only 30-35% of patients with positive surgical margins after radical prostatectomy develop recurrent disease. Adjuvant radiotherapy reduces the rate of biochemical relapse or metastasis and improves overall survival after radical prostatectomy. Various pathological factors, such as location and extent of positive margins, have been proposed as possible prognostic factors in men with margin-positive prostate cancer, however, the recent International Society of Urological Pathology consensus meeting in Boston noted that there is limited data on the significance of Gleason grade of the carcinoma at a positive margin. The present study shows that the presence of high grade prostate cancer, i.e. Gleason pattern 4 or 5, at a positive surgical margin is an independent predictor of biochemical recurrence after radical prostatectomy. Moreover, patients with lower grade carcinoma at the margin have a similar prognosis to men with negative margins. Hence, assessment of Gleason grade at the site of positive margin may aid optimal selection of patients for adjuvant radiotherapy.

OBJECTIVE

• To establish predictors of biochemical recurrence by analysing the pathological characteristics of positive surgical margins (PSMs), including Gleason grade of the carcinoma at the involved margin.

PATIENTS AND METHODS

• Clinicopathological and outcome data on 940 patients who underwent radical prostatectomy (RP) between 1997 and 2003 were collected. • Of these, 285 (30.3%) patients with PSMs were identified for pathological review, including assessment of location of margin, linear extent, number of PSMs, plane of margin and Gleason grade (3 vs 4 or 5) at the margin.

RESULTS

• At a median follow-up of 82 months, the biochemical recurrence rate of the PSM cohort was 29%. • On univariate analysis, the presence of Gleason grade 4 or 5 at the margin (34.4% of cases) was significantly associated with biochemical recurrence (hazard ratio [HR] 2.80, 95% confidence interval [CI]= 1.82-4.32, P < 0.001) compared with the presence of Gleason grade 3. • Linear extent of margin involvement was also associated with recurrence (P= 0.009). • Single vs multiple margin involvement, location, and plane of the involved margin were not significant predictors of recurrence. • On multivariate analysis, Gleason grade 4 or 5 at the margin remained an independent predictor of recurrence (HR 2.14, 95% CI = 1.29-4.03, P= 0.003).

CONCLUSION

• The Gleason grade at the site of a PSM identifies patients at increased risk of biochemical recurrence and should aid stratification of patients for adjuvant radiation therapy.

Solitary and small (≤3 mm) apical positive surgical margins are related to biochemical recurrence after radical prostatectomy

OBJECTIVES

To evaluate the prognostic value of positive surgical margins (PSM) in radical prostatectomy (RPE) specimens in relation to multifocality, localization and size.

METHODS

A total of 1036 patients who underwent RPE and staged pT2-3a,pN0,M0 were evaluated. None had received adjuvant or neoadjuvant therapy. All specimens were routinely processed by complete whole mount sectioning. Exact number, localization and size of PSM were reassessed, and patients were followed up for a mean of 60 months.

RESULTS

A total of 267 patients (26%) showed PSM (20% pT2, 48% pT3a). Preoperative prostate-specific antigen, Gleason score (GS) and PSM were independent predictors of biochemical recurrence (BCR). BCR-free survival rates for patients with and without PSM were 59% and 80%, respectively (HR 2.1; P < 0.001). PSM were related to biochemical failure in pT2 and pT3a tumors (P = 0.001 and P = 0.015). A total of 64% of solitary PSM were apical. Multifocality, localization and size of PSM had no significant impact on BCR.

CONCLUSIONS

Solitary apical and small PSM in RPE have a significant impact on BCR-free survival in localized stages.