Prostate-specific antigen half-life: a new predictor of progression-free survival and overall survival in Chinese prostate cancer patients

Intermediate PSA half-life after neoadjuvant hormone therapy predicts reduced risk of castration-resistant prostate cancer development after radical prostatectomy

Background

The magnitude and rapidity of the tumor response to androgen deprivation is known to predict the durability of the therapy. We have investigated the predictive value of categorizing patients by the half-life of PSA under neoadjuvant androgen deprivation therapy in patients with biochemical recurrence after radical prostatectomy.

Methods

Medical records of 317 patients who received neoadjuvant androgen deprivation therapy before radical prostatectomy and developed biochemical recurrence were analyzed. The patients were categorized into five groups according to PSA half-life. Risk of developing castration resistance was evaluated by Kaplan-Meier analysis and by Cox proportional risk regression analysis.

Results

The median follow-up duration was 50.1 months (IQR 31.8–68.7) and median PSA half-life was 22.1 days (IQR 12.7–38.4). Comparison of survival curves revealed that patients in the intermediate response group showed significantly lower 5-year castration-resistant prostate cancer rate (37.5%) compared to non-response and ultra-rapid response groups (63.6%, p = 0.007; 56.1%, p = 0.031; respectively). In the multivariate regression model, intermediate response compared to non-response was associated with significantly reduced risk of castration resistance development (hazard ratio 0.397, 95% confidence interval 0.191–0.823, p = 0.013) and overall mortality (hazard ratio 0.138, 95% confidence interval 0.033–0.584, p = 0.007). When subcategorized by Gleason score, Kaplan-Meier curve revealed that, in the high Gleason score stratum, 5-year castration-resistant prostate cancer rate for intermediate response group (44.0%) was exceptionally lower than that in non-response group (66.7%, p = 0.047), while castration resistance increased in other groups.

Conclusion

Short PSA half-life as well as no response after androgen deprivation is associated with increased risk of treatment failure compared to intermediate PSA half-life.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3775-6) contains supplementary material, which is available to authorized users.

The role of gonadotrophin-releasing hormone antagonists in the treatment of patients with advanced hormone-dependent prostate cancer in the UK

Purpose

Comparing gonadotrophin-releasing hormone (GnRH) antagonists and agonists as androgen deprivation therapy for advanced prostate cancer (PC).

Methods

This article stems from a round-table meeting in December 2014 to compare the properties of GnRH agonists and antagonists in the published literature in order to identify the patient groups most likely to benefit from GnRH antagonist therapy. A broad PubMed and congress abstract search was carried out in preparation for the meeting to ensure that the latest data and opinion were available for the discussions.

Results

In randomised, controlled trials, GnRH antagonist therapy provides more rapid suppression of luteinising hormone, follicle-stimulating hormone and testosterone than GnRH agonist treatment. Compared with the GnRH agonist, there is evidence of improved disease control by a GnRH antagonist, with longer interval to prostate-specific antigen progression and greater reduction of serum alkaline phosphatase. In a post hoc analysis of six randomised trials, the risk of cardiac events within 1 year of initiating therapy was significantly lower among men receiving GnRH antagonist than agonist. Pre-clinical laboratory data suggest a number of mechanisms whereby GnRH antagonist therapy may benefit men with pre-existing cardiovascular disease (CVD), the most plausible hypothesis being that, unlike GnRH agonists, GnRH antagonists do not activate T lymphocytes, which act to increase atherosclerotic plaque rupture.

Conclusion

When making treatment decisions, clinicians should consider comorbidities, particularly CVD, in addition to effects on PC. GnRH antagonists may be appropriate in patients with significant CV risk, existing osteopenia, lower urinary tract symptoms and significant metastatic disease.

Degarelix monotherapy compared with luteinizing hormone-releasing hormone (LHRH) agonists plus anti-androgen flare protection in advanced prostate cancer: an analysis of two randomized controlled trials

OBJECTIVES

The objective of this study was to assess differences in efficacy outcomes between luteinizing hormone-releasing hormone (LHRH) agonist plus antiandrogen (AA) flare protection and monotherapy with the gonadotrophin-releasing hormone antagonist degarelix in patients with prostate cancer.

METHODS

Data from 1455 patients were pooled from two prospective, phase III randomized 1-year clinical trials of degarelix versus LHRH agonist with or without AA. The AA bicalutamide was administered at the investigator's discretion. Adjusted hazard ratios (HRs) were calculated using a Cox proportional hazards regression model and a conditional logistic regression model was used for a case-control analysis of odds ratios (ORs).

RESULTS

Patients received degarelix monotherapy (n = 972) or LHRH agonist (n = 483) of whom 57 also received AA. Overall, prostate-specific antigen progression-free survival (PSA PFS) was improved with degarelix versus LHRH agonist + AA (Cox proportional hazards regression model-adjusted HR for PSA PFS failure was 0.56 [95% confidence interval (CI) 0.33-0.97, p = 0.038]). To compensate for a higher proportion of patients with metastases, Gleason score 7-10, and PSA >20 ng/ml in the LHRH agonist + AA group, a case-control analysis using a conditional logistic regression model was utilized. This resulted in an OR for PSA PFS of 0.42 (95% CI 0.20-0.89; p = 0.023) in the overall population, and 0.35 (95% CI 0.13-0.96; p = 0.042) in patients with PSA >50 ng/ml at baseline, when treated with degarelix versus LHRH agonists + AA. There were a small number of deaths, 1.9% with degarelix and 7% with LHRH agonists + AA (case-control analysis OR = 0.37; p = 0.085).

CONCLUSIONS

Degarelix monotherapy produced a more favorable effect on PSA PFS outcomes than a LHRH agonist + AA flare protection therapy in patients with prostate cancer when a case-control analysis was used to compensate for differences between treatment groups.

Degarelix therapy for prostate cancer in a real-world setting: experience from the German IQUO (Association for Uro-Oncological Quality Assurance) Firmagon® registry

Background

We investigated the use of the gonadotropin-releasing hormone (GnRH) antagonist degarelix in everyday clinical practice using registry data from uro-oncology practices in Germany.

Methods

Data were analysed retrospectively from the IQUO (Association for uro-oncological quality assurance) patient registry. Data were prospectively collected from all consecutive PCa patients treated with degarelix (n = 1010) in 138 uro-oncology practices in Germany between May 2009 and December 2013.

Results

Median overall survival had not yet been reached in the all-patient group or in subgroups who had or had not received prior hormonal therapy (HT). Cox regression analysis showed that patients who had received prior HT (n = 542) had a 58 % increased mortality risk (hazard ratio 1.58, 95 % CI 1.20–2.09) versus patients who had not (n = 468) (p = 0.001). Also, in patients who had received prior luteinizing hormone-releasing hormone (LHRH) analogue therapy (LHRH agonists or GnRH antagonists), median time to PSA progression was shorter (209 weeks) than in those who had not received prior LHRH analogues (n = 555; median PSA progression-free survival not yet reached). Degarelix was generally well tolerated.

Conclusions

Degarelix was effective and well tolerated in everyday clinical practice, confirming observations from clinical studies. Patients who received prior HT appeared to have a significantly higher mortality risk.

Constitutively active AR-V7 plays an essential role in the development and progression of castration-resistant prostate cancer

This study aimed to investigate the role of AR-V7 in development of castration-resistant prostate cancer (CRPC) and to determine whether the AR-V7 expression in CRPC tissues can predict cancer-specific survival. We enrolled 100 localized prostate cancer (PCa) (cohort 1), 104 newly diagnosed metastatic PCa (cohort 2), and 46 CRPC (cohort 3) patients treated at our institution. The expression of AR-V7 in PCa was assessed by immunohistochemistry. Cox regression models were used to evaluate the predictive role of all covariates for the development of CRPC in cohort 2 and for cancer-specific survival in cohort 3. Time to CRPC and cancer-specific survival curves were estimated using the Kaplan-Meier method. AR-V7 expression rate in cohort 3 was significantly elevated compared with other two cohorts (p < 0.001). Multivariate analysis revealed that AR-V7 was an independent predictive factor for CRPC development (HR = 2.627, p = 0.001) and for cancer specific survival (HR = 2.247, p = 0.033). Furthermore, the AR-V7 expression was associated with shorter survival in CRPC patients. Our results demonstrated protein AR-V7 levels in primary tumors can be used as a predictive marker for the development of CRPC and as a prognostic factor in CRPC patients. Therapy targeting AR-V7 may help prevent PCa progression and improve the prognosis of CRPC patients.

Correlation Between Testosterone and PSA Kinetics in Metastatic Prostate Cancer Patients Treated With Diverse Chemical Castrations

To assess total testosterone and prostatic-specific antigen (PSA) kinetics among diverse chemical castrations, advanced-stage prostate cancer patients were randomized into three groups of 20: Group 1, Leuprolide 3.75 mg; Group 2, Leuprolide 7.5 mg; and Group 3, Goserelin 3.6 mg. All groups were treated with monthly application of the respective drugs. The patients' levels of serum total testosterone and PSA were evaluated at two time periods: before the treatment and 3 months after the treatment. Spearman's rank correlation coefficient was utilized to verify the hypothesis of linear correlation between total testosterone and PSA levels. At the beginning the patients' age, stage, grade, PSA, and total testosterone were similar within the three groups, with median age 72, 70, and 70 years in Groups 1, 2, and 3, respectively. Three months after the treatment, patients who received Leuprolide 7.5 mg presented significantly lower median total testosterone levels compared with Goserelin 3.6 mg and Leuprolide 3.75 mg (9.5 ng/dL vs. 20.0 ng/dL vs. 30.0 ng/dL, respectively; p = .0072), while those who received Goserelin 3.6 mg presented significantly lower PSA levels compared with Leuprolide 7.5 mg and Leuprolide 3.75 mg (0.67 vs. 1.86 vs. 2.57, respectively; p = .0067). There was no linear correlation between total testosterone and PSA levels. Overall, regarding castration levels of total testosterone, 28.77% of patients did not obtain levels ≤50 ng/dL and 47.80% did not obtain levels ≤20 ng/dL. There was no correlation between total testosterone and PSA kinetics and no equivalence among different pharmacological castrations.

A critical review of the analytical approaches for circulating tumor biomarker kinetics during treatment

Changes in serum tumor biomarkers may indicate treatment efficacy. Traditional tumor markers may soon be replaced by novel serum biomarkers, such as circulating tumor cells (CTCs) or circulating tumor nucleic acids. Given their promising predictive values, studies of their kinetics are warranted. Many methodologies meant to assess kinetics of traditional marker kinetics during anticancer treatment have been reported. Here, we review the methodologies, the advantages and the limitations of the analytical approaches reported in the literature. Strategies based on a single time point were first used (baseline value, normalization, nadir, threshold at a time t), followed by approaches based on two or more time points [half-life (HL), percentage decrease, time-to-events…]. Heterogeneities in methodologies and lack of consideration of inter- and intra-individual variability may account for the inconsistencies and the poor utility in routine. More recently, strategies based on a population kinetics approach and mathematical modeling have been reported. The identification of equations describing individual kinetic profiles of biomarkers may be an alternative strategy despite its complexity and higher number of necessary measurements. Validation studies are required. Efforts should be made to standardize biomarker kinetic analysis methodologies to ensure the optimized development of novel serum biomarkers and avoid the pitfalls of traditional markers.

DNA aptamer evolved by cell-SELEX for recognition of prostate cancer

Morbidity and mortality of prostate cancer (PCa) have increased in recent years worldwide. Currently existing methods for diagnosis and treatment do not make the situation improve, especially for hormone refractory prostate cancer (HRPC). The lack of molecular probes for PCa hindered the early diagnosis of metastasis and accurate staging for PCa. In this work, we have developed a new aptamer probe Wy-5a against PCa cell line PC-3 by cell-SELEX technique. Wy-5a shows high specificity to the target cells with dissociation constants in the nanomolar range, and does not recognize other tested PCa cell lines and other tested tumor cell lines. The staining of clinical tissue sections with fluorescent dye labeled Wy-5a shows that sections from high risk group with metastasis exhibited stronger fluorescence and sections from Benign Prostatic Hyperplasia (BPH) did not exhibit notable fluorescence, which suggests that aptamer Wy-5a may bind to protein related to the progression of PCa. The high affinity and specificity of Wy-5a makes this aptamer hold potential for application in diagnosis and target therapy of PCa.

Potential value of rapid prostate-specific antigen decline in identifying primary resistance to abiraterone acetate and enzalutamide

ABSTRACT: 

Aim: To identify factors predicting primary resistance to new-generation hormonal agents (NHAs), abiraterone acetate and enzalutamide in patients with castration-resistant prostate cancer (CRPC). Patients & methods: Our hospital has conducted two successive named patient NHA programs. A total of 57 patients with progressive CRPC previously treated with first-line docetaxel-based chemotherapy received standard NHA doses: abiraterone acetate 1000 mg once-daily combined with prednisone (5 mg twice daily) or enzalutamide 160 mg once-daily. Patients, who were assessed monthly to check their hematological parameters and prostate-specific antigen (PSA) levels, also underwent imaging investigations every 3–4 months. In total, 24 variables were assessed as potential predictors of primary NHA resistance. Results: Univariate analysis indicated that baseline pain and lactate dehydrogenase levels, and PSA levels after 1 month’s treatment were predictive of primary NHA resistance. Only the predictive value of PSA levels after 1 month of treatment was confirmed at multivariate analysis. This factor strongly predicted progression-free and overall survival. Conclusion: Results suggest the use of a simple and rapid method of identifying patients with primary resistance to NHAs: patients not achieving a ≥50% reduction in PSA levels within the first treatment month should undergo intensive investigations to verify whether they have primary resistance to NHAs.

Experience with degarelix in the treatment of prostate cancer

Degarelix is a gonadotrophin-releasing hormone (GnRH) antagonist for the first-line treatment of androgen-dependent advanced prostate cancer. It has a direct mechanism of action that blocks the action of GnRH on the pituitary with no initial surge in gonadotrophin or testosterone levels. Degarelix is the most extensively studied and widely available GnRH antagonist worldwide. Clinical studies have demonstrated similar efficacy to the GnRH agonist leuprolide in achieving testosterone suppression in patients with prostate cancer. However, degarelix produces a faster suppression of testosterone and prostate-specific antigen (PSA), with no testosterone surge or microsurges, thus preventing the risk of clinical flare in advanced disease. Clinical trials have demonstrated that degarelix can offer improved disease control when compared with a GnRH agonist in terms of superior PSA progression-free survival (suggesting that degarelix likely delays progression to castration-resistant disease), and a more significant impact on bone serum alkaline phosphatase and follicle-stimulating hormone. Degarelix is generally well tolerated, with no reports of systemic allergic reactions in any clinical studies. In conclusion, degarelix offers clinicians a rational first-line hormonal monotherapy option for the management of advanced prostate cancer.

The prognostic factors of effective ketoconazole treatment for metastatic castration-resistant prostate cancer: who can benefit from ketoconazole therapy?

We investigated the prognostic value of some variables of effective ketoconazole treatment for metastatic castration-resistant prostate cancer (mCRPC). In total, 163 patients with mCRPC were eligible, receiving ketoconazole 200-400 mg three times daily with replacement doses of prednisone. Progression-free survival (PFS) was calculated from the beginning of the ketoconazole therapy to the onset of disease progression. The prognostic value of different variables for PFS was assessed by Cox regression analysis. The median PFS was 2.6 months (0.5-8.6 months) for these patients. The serum testosterone level changed during therapy, which decreased when the prostate-specific antigen (PSA) declined; the serum testosterone level increased as the levels of PSA relapsed. The median PFS values for patients associated with different factors were the following: 1.4 and 3.5 months for a nadir PSA of ≥ 0.2 and <0.2 ng ml(-1), respectively (hazard rate (HR)=4.767, P<0.001); 3.1 and 1.6 months for a baseline testosterone of ≥ 0.1 and <0.1 ng ml(-1), respectively (HR=2.865, P=0.012); 2.8 and 1.9 months for a baseline haemoglobin of ≥ 120 and <120 g l(-1), respectively (HR=1.605, P<0.001); and 3.0 and 1.9 months for a PSA doubling time (PSADT) of ≥ 2.0 and <2.0 months, respectively (HR=1.454, P=0.017). A risk model was constructed according to the four factors that divided patients into three subgroups of low risk (0-1 factors), moderate risk (2 factors) and high risk (3-4 factors) with PFS values of 3.6, 3.0 and 1.4 months, respectively (HR=1.619, P<0.001). A nadir PSA of ≥ 0.2 ng ml(-1), a baseline testosterone of <0.1 ng ml(-1), a baseline haemoglobin of <120 g l(-1) and a PSADT of <2 months were associated with a poor PFS. This risk model could provide evidence to predict the survival benefit of ketoconazole therapy.

Androgen deprivation therapy: past, present and future

Since Huggins and Hodges demonstrated the responsiveness of prostate cancer to androgen deprivation therapy (ADT), androgen-suppressing strategies have formed the cornerstone of management of advanced prostate cancer. Approaches to ADT have included orchidectomy, oestrogens, luteinizing hormone-releasing hormone (LHRH) agonists, anti-androgens and more recently the gonadotrophin-releasing hormone antagonists. The most extensively studied antagonist, degarelix, avoids the testosterone surge and clinical flare associated with LHRH agonists, offering more rapid PSA and testosterone suppression, improved testosterone control and improved PSA progression-free survival compared with agonists. The clinical profile of degarelix appears to make it a particularly suitable therapeutic option for certain subgroups of patients, including those with metastatic disease, high baseline PSA (>20 ng/mL) and highly symptomatic disease. As well as forming the mainstay of treatment for advanced prostate cancer, ADT is increasingly used in earlier disease stages. While data from clinical trials support the use of ADT neoadjuvant/adjuvant to radiotherapy for locally advanced or high-risk localized prostate cancer, it remains to be established whether specific ADT classes/agents provide particular benefits in this clinical setting.

Gonadotropin-releasing hormone: an update review of the antagonists versus agonists

Gonadotropin-releasing hormone agonists and antagonists provide androgen-deprivation therapy for prostate cancer. Unlike agonists, gonadotropin-releasing hormone antagonists have a direct mode of action to block pituitary gonadotropin-releasing hormone receptors. There are two licensed gonadotropin-releasing hormone antagonists, degarelix and abarelix. Of these, degarelix is the more extensively studied and has been documented to be more effective than the well-established, first-line agonist, leuprolide, in terms of substantially faster onset of castration, faster suppression of prostate-specific antigen, no risk for testosterone surge or clinical flare, and improved prostate-specific antigen progression-free survival, suggesting a delay in castration resistance. Other than minor injection-site reactions, degarelix is generally well tolerated, without systemic allergic reactions and with most adverse events consistent with androgen suppression or the underlying condition. In conclusion, degarelix provides a rational, first-line androgen-deprivation therapy suitable for the treatment of prostate cancer, with faster onset of castration than with agonists, and no testosterone surge. Furthermore, data suggest that degarelix improves disease control compared with leuprolide, and might delay the onset of castration-resistant disease. In view of these clinical benefits and the lack of need for concomitant anti-androgen treatment, gonadotropin-releasing hormone antagonists might replace gonadotropin-releasing hormone agonists as first-line androgen-deprivation therapy in the future.

[Survival is associated with time to reach PSA nadir (DAN) and the ratio DAN/nadir value after androgen deprivation for prostate cancer]

OBJECTIVE

The objective of this study was to assess the prognostic decrease rate of PSA in patients treated with androgen suppression (AS) for prostate cancer (PCa).

METHODS

We identified in our database CaP patients with histologically documented, treated with SA alone and for whom vital status with a minimum follow-up of 6 months (except death beforehand) was established. Patient characteristics and CaP and PSA at baseline, PSA nadir, time of reaching the nadir PSA (DAN) and the ratio of the DAN/nadir value (ratio DAN/Nadir) were analyzed in relation to progression-free survival, specific and overall survival.

RESULTS

One hundred ninety eight patients met the inclusion criteria and the median was 61.5 months (range 4.8 to 233). The median PSA at the start of the SA were 37.1 ng/mL and the median nadir PSA was 0.48 ng/mL. The median time to progression was 23.6 months. The median specific and overall survivals were 94 and 78 months, respectively. In univariate analysis, predictors of progression-free survival were PSA before SA, PSA nadir, DAN, DAN ratio/nadir, Gleason score, the percentage of core positive prostate biopsy and the status of bone scintigraphy. Except for PSA before SA which was no longer significant, predictors of specific and overall survival were similar and added the biochemical response (decrease of more than 50% of PSA) to a second hormonal manipulation during the biological progression. In multivariate analysis, the nadir PSA and the ratio DAN/Nadir remained significant predictors.

CONCLUSION

These results have confirmed in one hand the predictive value of survival in patients DAN SA for CaP: achieving faster nadir PSA was associated with shorter survival. They have introduced in the other hand the new concept of DAN/Nadir PSA which provides independent prognostic information.

Serum prostate-specific antigen value adjusted for non-cancerous prostate tissue volume in patients undergoing radical prostatectomy: a new predictor of biochemical recurrence in localized or locally advanced prostate cancer

The aim of this study was to investigate the significance of serum prostate-specific antigen (PSA) value adjusted for total tumor volume (PSA/tumor volume) and serum PSA value adjusted for non-cancerous prostate tissue volume (NCPV) (PSA/NCPV) as a predictor of pathological findings and clinical outcome after radical prostatectomy. Clinical and pathological data of 407 patients (median age: 66.5 years; range: 41.8-85.7 years) were reviewed retrospectively. The median follow-up period was 18.1 months (range: 1.0-107.8 months). Biochemical recurrence was defined as detectable PSA levels (greater than 0.2 ng ml(-1)) and the time of biochemical recurrence was taken to be the first time PSA became detectable. In the multivariate model, PSA/NCPV was an independent predictor of extracapsular extension and positive surgical margin (P<0.05), but PSA/tumor volume was not. Kaplan-Meier curves revealed that PSA/NCPV correlated with biochemical recurrence-free survival (P<0.001; log-rank test) but PSA/tumor volume did not (P=0.275; log-rank test). PSA/NCPV was also a significant independent prognostic factor for biochemical recurrence-free survival on multivariate Cox proportional hazard analysis (P=0.004, relative risk=2.42). Our findings suggest that PSA/NCPV is associated independently with extracapsular extension and surgical margin status and may be an independent prognostic variable of PSA recurrence after radical prostatectomy.