Serum prostate-specific antigen (PSA) concentration is positively associated with rate of disease reclassification on subsequent active surveillance prostate biopsy in men with low PSA density

Low risk is low risk, regardless of race or ethnicity: Outcomes of prostate cancer active surveillance and factors associated with reclassification in a racially diverse cohort

INTRODUCTION

Active surveillance (AS) is the standard for very low- and low-risk prostate cancer. Although risk factors for pathologic reclassification while on AS have been identified, results are mixed for non-Hispanic Black (NHB) and Hispanic ethnicity. We aim to further explore how race and ethnicity may be affecting AS participation and outcomes in a primarily urban, diverse, and vulnerable population.

MATERIALS AND METHODS

Patients eligible for AS from 2005-2020 were reviewed. Demographics, race/ethnicity, prostate specific antigen (PSA), prostate volume, and pathologic characteristics were analyzed between patients enrolled in AS and those that underwent immediate therapy. Kaplan-Meier survival analysis was used to compare biochemical recurrence (BCR) rates. Cox proportional hazards models were used to develop prediction models for clinical reclassification.

RESULTS

A total of 471 men were eligible for AS. Of those, 188 (39.9%) enrolled in AS while 283 (60.1%) underwent immediate radical therapy. No significant differences were found in racial/ethnic composition between the AS and immediate treatment groups. In our AS cohort, 79 (42.0%) experienced clinical reclassification and underwent deferred treatment. BCR rates were similar between treatment groups. Race/ethnicity were not found to be predictors of clinical reclassification, while metrics at diagnostic biopsy such as elevated PSA, higher PSA density, and lower prostate volume increased reclassification odds.

CONCLUSIONS

In our diverse population, NHB race and Hispanic ethnicity were not significant predictors of adverse reclassification while on AS. Our findings support utilizing other metrics taken at initial biopsy to identify high-risk patients such as PSA, prostate volume, and PSA density.

Active Surveillance in Prostate Cancer: Role of Available Biomarkers in Daily Practice

Prostate cancer (PCa) is the most commonly diagnosed cancer in men. The diagnosis is currently based on PSA levels, which are associated with overdiagnosis and overtreatment. Moreover, most PCas are localized tumours; hence, many patients with low-/very low-risk PCa could benefit from active surveillance (AS) programs instead of more aggressive, active treatments. Heterogeneity within inclusion criteria and follow-up strategies are the main controversial issues that AS presently faces. Many biomarkers are currently under investigation in this setting; however, none has yet demonstrated enough diagnostic ability as an independent predictor of pathological or clinical progression. This work aims to review the currently available literature on tissue, blood and urine biomarkers validated in clinical practice for the management of AS patients.

The impact of pretreatment PSA on risk stratification in men with Gleason 6 prostate cancer: Implications for active surveillance

BACKGROUND

There are limited data to support the safety of active surveillance in men with favorable-intermediate risk prostate cancer due only to a prostate specific antigen (PSA) above 10 ng/ml. We therefore evaluated the impact of pretreatment PSA on risk-stratification in men with Gleason 6 prostate cancer.

METHODS

We identified men aged 18 to 75 with cT1-2cN0cM0, pre-treatment PSA < 20 ng/ml, Gleason 6 prostate cancer diagnosed from 2010 to 2016 in the National Cancer Database who underwent radical prostatectomy. The associations of patient and disease features with Gleason score upgrading or adverse pathologic features at prostatectomy were evaluated using logistic regression. To evaluate for non linear relationships between PSA and each outcome, we examined predicted marginal event rates standardized for baseline characteristics with PSA modeled using restricted cubic splines RESULTS: A total of 75,566 patients were included in the cohort. In unadjusted analyses, patients with pretreatment PSA ≥ 10 ng/ml had higher rates of Gleason core upgrading (58.8% vs. 47.9%; P< 0.001) and adverse pathologic features (19.7% vs. 10.0%; P< 0.001) compared to patients with PSA < 10 ng/ml. In multivariable analyses, PSA ≥ 10 ng/ml was associated with statistically significantly increased risks of Gleason score upgrading (OR 1.47;95%CI 1.39 - 1.55) and adverse pathologic features (OR 2.15;95%CI 2.01 - 2.30). When modeled as a non linear continuous covariate, PSA was associated with increased adjusted rates of Gleason score upgrading and adverse pathologic features without a clear dichotomization at a threshold of 10 ng/ml.

CONCLUSION

Higher pretreatment PSA was independently associated with increased risks of Gleason score upgrading and adverse pathologic features at prostatectomy. Flexible modeling of the relationship between PSA and each outcome did not support dichotomization at a threshold of 10 ng/ml. These results can be used to improve patient risk-stratification for active surveillance.

How can we predict the active surveillance candidates meeting all Epstein criteria prior to prostate biopsy to avoid overdiagnosis?

OBJECTIVE

To investigate the effectiveness of PSA, prostate volume (PV) and free-to-total PSA ratio (fPSA%) in predicting patients meeting all active surveillance criteria, including Epstein criteria.

METHOD

Retrospective analysis was made of the data of 1901 men who underwent transrectal ultrasound (TRUS)-guided prostate biopsy in our clinic between January 2015 and December 2019. The active surveillance criteria were determined as Gleason score ≤6, when specified ≤2 positive cores with <50% cancer involvement in every positive core, a clinical T1c, a PSA <10ng/mL and a PSA density <0.15 ng/mL/cc. Patients who met all active surveillance criteria were included in Group 1, and other patients with prostate cancer were included in Group 2.

RESULTS

The study included 336 patients with available data of age, total-free PSA levels, PV calculated by TRUS. Group 1 consisted of 82 patients and Group 2 consisted of 254 patients. PV and fPSA% were significantly higher and PSA was significantly lower in Group 1 than in Group 2. On multivariate analysis, the independent predictors were determined to be PSA and PV while fPSA% was not.

CONCLUSION

By using PSA and PV in predicting patients meeting all active surveillance criteria, unnecessary biopsies and ultimately overdiagnosis can be reduced.

Prostate-specific antigen density is predictive of outcome in suboptimal prostate seed brachytherapy

PURPOSE

In prostate seed brachytherapy, a D₉₀ of <130 Gy is an accepted predictive factor for biochemical failure (BF). We studied whether there is a subpopulation that does not need additional treatment after a suboptimal permanent seed brachytherapy implantation.

METHODS AND MATERIALS

A total of 486 patients who had either BF or a minimum followup of 48 months without BF were identified. BF was defined according to the Phoenix definition (nadir prostate-specific antigen + 2). Univariate and multivariate analyses were performed, adjusting for known prognostic factors such as D₉₀ and prostate-specific antigen density (PSAD) of ≥0.15 ng/mL/cm³, to evaluate their ability to predict BF.

RESULTS

Median followup for patients without BF was 72 months (interquartile range 56-96). BF-free recurrence rate at 5 years was 95% and at 8 years 88%. In univariate analysis, PSAD and cancer of the prostate risk assessment score were predictive of BF. On multivariate analysis, none of the factors remained significant. The best prognosis had patients with a low PSAD (<0.15 ng/mL/cm³) and an optimal implant at 30 days after implantation (as defined by D₉₀ ≥ 130 Gy) compared to patients with both factors unfavorable (p = 0.006). A favorable PSAD was associate with a good prognosis, independently of the D₉₀ (<130 Gy vs. ≥130 Gy, p = 0.7).

CONCLUSIONS

Patients with a PSAD of <0.15 ng/mL/cm³ have little risk of BF, even in the case of a suboptimal implant. These results need to be validated in other patients' cohorts.

Active surveillance for prostate cancer: current evidence and contemporary state of practice

Prostate cancer remains one of the most commonly diagnosed malignancies worldwide. Early diagnosis and curative treatment seem to improve survival in men with unfavourable-risk cancers, but significant concerns exist regarding the overdiagnosis and overtreatment of men with lower-risk cancers. To this end, active surveillance (AS) has emerged as a primary management strategy in men with favourable-risk disease, and contemporary data suggest that use of AS has increased worldwide. Although published surveillance cohorts differ by protocol, reported rates of metastatic disease and prostate-cancer-specific mortality are exceedingly low in the intermediate term (5-10 years). Such outcomes seem to be closely associated with programme-specific criteria for selection, monitoring, and intervention, suggesting that AS--like other management strategies--could be individualized based on the level of risk acceptable to patients in light of their personal preferences. Additional data are needed to better establish the risks associated with AS and to identify patient-specific characteristics that could modify prognosis.

Radiation Treatment of Lymph Node Recurrence from Prostate Cancer: Is 11C-Choline PET/CT Predictive of Survival Outcomes?

PET/CT is a valuable tool to detect lymph node (LN) metastases in patients with biochemical failure after primary treatment for prostate cancer (PCa). The aim was to assess the predictive role of imaging parameters derived by (11)C-choline PET/CT on survival outcomes-overall survival, locoregional relapse-free survival, clinical relapse-free survival (cRFS), and biochemical relapse-free survival (bRFS)-in patients treated with helical tomotherapy (HTT) for LN recurrence.

METHODS

This retrospective study included 68 patients affected by PCa (mean age, 68 y; age range, 51-81 y) with biochemical recurrence after primary treatment (median prostate-specific antigen values obtained at the time of PET/CT scan, 2.42 ng/mL; range, 0.61-27.56 ng/mL) who underwent (11)C-choline PET/CT from January 2005 to January 2013 and were treated with HTT in correspondence of the pathologic choline LN uptake. PET-derived parameters, including maximum/mean standardized uptake value (SUVmax and SUVmean, respectively) and metabolic tumor volume (MTV) with a threshold of 40%, 50%, and 60% were calculated. The best cutoff values of PET-derived parameters discriminating between patients with and without relapse, after treatment guided by PET, were assessed by receiver-operating-characteristic (ROC) curve analysis. Univariate and multivariate Cox regression analysis including the most predictive PET-derived parameters and survival outcomes were performed.

RESULTS

The median follow-up was 20 mo (mean, 26 mo; range, 3-97 mo). (11)C-choline PET/CT showed pathologic LN uptake in 4 patients at the pelvic level, in 5 at the abdominal level, in 13 at both the pelvic and the abdominal level, and in 46 at the abdominal or pelvic or other sites. The 2-y overall survival, locoregional relapse-free survival, cRFS, and bRFS were 87%, 91%, 51%, and 40%, respectively. On the basis of ROC curves, the most discriminative cutoff value for MTV values was an MTV threshold of 60% (MTV60) of greater than 0.64 cm(3). No significant cutoff values were found for SUVmax or SUVmean at univariate analysis, whereas MTV60 was confirmed as an independent predictor in multivariate analysis and significantly correlated with bRFS and cRFS. MTV60 and extrapelvic disease well predict the risk of cRFS.

CONCLUSION

(11)C-choline PET/CT performed as a guide for HTT on LN recurrence is predictive of survival. In particular, MTV60 and extrapelvic disease were the best predictors of tumor response for bRFS and cRFS in PCa patients with LN recurrence after primary treatment. This information may be useful in emerging treatment strategies.

Intermediate and Longer-Term Outcomes From a Prospective Active-Surveillance Program for Favorable-Risk Prostate Cancer

PURPOSE

To assess long-term outcomes of men with favorable-risk prostate cancer in a prospective, active-surveillance program.

METHODS

Curative intervention was recommended for disease reclassification to higher cancer grade or volume on prostate biopsy. Primary outcomes were overall, cancer-specific, and metastasis-free survival. Secondary outcomes were the cumulative incidence of reclassification and curative intervention. Factors associated with grade reclassification and curative intervention were evaluated in a Cox proportional hazards model.

RESULTS

A total of 1,298 men (median age, 66 years) with a median follow-up of 5 years (range, 0.01 to 18.00 years) contributed 6,766 person-years of follow-up since 1995. Overall, cancer-specific, and metastasis-free survival rates were 93%, 99.9%, and 99.4%, respectively, at 10 years and 69%, 99.9%, and 99.4%, respectively, at 15 years. The cumulative incidence of grade reclassification was 26% at 10 years and was 31% at 15 years; cumulative incidence of curative intervention was 50% at 10 years and was 57% at 15 years. The median treatment-free survival was 8.5 years (range, 0.01 to 18 years). Factors associated with grade reclassification were older age (hazard ratio [HR], 1.03 for each additional year; 95% CI, 1.01 to 1.06), prostate-specific antigen density (HR, 1.21 per 0.1 unit increase; 95% CI, 1.12 to 1.46), and greater number of positive biopsy cores (HR, 1.47 for each additional positive core; 95% CI, 1.26 to 1.69). Factors associated with intervention were prostate-specific antigen density (HR, 1.38 per 0.1 unit increase; 95% CI, 1.22 to 1.56) and a greater number of positive biopsy cores (HR, 1.35 for one additional positive core; 95% CI, 1.19 to 1.53).

CONCLUSION

Men with favorable-risk prostate cancer should be informed of the low likelihood of harm from their diagnosis and should be encouraged to consider surveillance rather than curative intervention.

Active surveillance for prostate cancer: a systematic review of clinicopathologic variables and biomarkers for risk stratification

CONTEXT

Active surveillance (AS) is an important strategy to reduce prostate cancer overtreatment. However, the optimal criteria for eligibility and predictors of progression while on AS are debated.

OBJECTIVE

To review primary data on markers, genetic factors, and risk stratification for patient selection and predictors of progression during AS.

EVIDENCE ACQUISITION

Electronic searches were conducted in PubMed, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to April 2014 for original articles on biomarkers and risk stratification for AS.

EVIDENCE SYNTHESIS

Patient factors associated with AS outcomes in some studies include age, race, and family history. Multiple studies provide consistent evidence that a lower percentage of free prostate-specific antigen (PSA), a higher Prostate Health Index (PHI), a higher PSA density (PSAD), and greater biopsy core involvement at baseline predict a greater risk of progression. During follow-up, serial measurements of PHI and PSAD, as well as repeat biopsy results, predict later biopsy progression. While some studies have suggested a univariate relationship between urinary prostate cancer antigen 3 (PCA3) and transmembrane protease, serine 2-v-ets avian erythroblastosis virus E26 oncogene homolog gene fusion (TMPRSS2:ERG) with adverse biopsy features, these markers have not been consistently shown to independently predict AS outcomes. No conclusive data support the use of genetic tests in AS. Limitations of these studies include heterogeneous definitions of progression and limited follow-up.

CONCLUSIONS

There is a growing body of literature on patient characteristics, biopsy features, and biomarkers with potential utility in AS. More data are needed on practical applications such as combining these tests into multivariable clinical algorithms and long-term outcomes to further improve AS in the future.

PATIENT SUMMARY

Several PSA-based tests (free PSA, PHI, PSAD) and the extent of cancer on biopsy can help to stratify the risk of progression during active surveillance. Investigation of several other markers is under way.

Extended followup and risk factors for disease reclassification in a large active surveillance cohort for localized prostate cancer

PURPOSE

Active surveillance to manage prostate cancer provides an alternative to immediate treatment in men with low risk prostate cancer. We report updated outcomes from a long-standing active surveillance cohort and factors associated with reclassification.

MATERIALS AND METHODS

We retrospectively reviewed data on all men enrolled in the active surveillance cohort at our institution with at least 6 months of followup between 1990 and 2013. Surveillance consisted of quarterly prostate specific antigen testing, repeat imaging with transrectal ultrasound at provider discretion and periodic repeat prostate biopsies. Factors associated with repeat biopsy reclassification and local treatment were determined by multivariate Cox proportional hazards regression. We also analyzed the association of prostate specific antigen density and outcomes stratified by prostate size.

RESULTS

A total of 810 men who consented to participate in the research cohort were followed on active surveillance for a median of 60 months. Of these men 556 (69%) met strict criteria for active surveillance. Five-year overall survival was 98%, treatment-free survival was 60% and biopsy reclassification-free survival was 40%. There were no prostate cancer related deaths. On multivariate analysis prostate specific antigen density was positively associated with the risk of biopsy reclassification and treatment while the number of biopsies and time between biopsies were inversely associated with the 2 outcomes (each p <0.01). When stratified by prostate volume, prostate specific antigen density remained significantly associated with biopsy reclassification for all strata but prostate specific antigen density was only significantly associated with treatment in men with a smaller prostate.

CONCLUSIONS

Significant prostate cancer related morbidity and mortality remained rare at intermediate followup. Prostate specific antigen density was independently associated with biopsy reclassification and treatment while on active surveillance.