EAU-ESTRO-SIOG Guidelines on Prostate Cancer. Part II: Treatment of Relapsing, Metastatic, and Castration-Resistant Prostate Cancer

Cost-effectiveness analyses and cost analyses in castration-resistant prostate cancer: A systematic review

Background

Treatment of metastatic prostate cancer is associated with high personal and economic burden. Recently, new treatment options for castration-resistant prostate cancer became available with promising survival advantages. However, cost-effectiveness of those new treatment options is sometimes ambiguous or given only under certain circumstances. The aim of this study was to systematically review studies on the cost-effectiveness of treatments and costs of castration-resistant prostate cancer (CRPC) and metastasizing castration-resistant prostate cancer (mCRPC) on their methodological quality and the risk of bias.

Methods

A systematic literature search was performed in the databases PubMed, CINAHL Complete, the Cochrane Library and Web of Science Core Collection for costs-effectiveness analyses, model-based economic evaluations, cost-of-illness analyses and budget impact analyses. Reported costs were inflated to 2015 US$ purchasing power parities. Quality assessment and risk of bias assessment was performed using the Consolidated Health Economic Evaluation Reporting Standards checklist and the Bias in Economic Evaluations checklist, respectively.

Results

In total, 38 articles were identified by the systematic literature search. The methodological quality of the included studies varied widely, and there was considerable risk of bias. The cost-effectiveness treatments for CRPC and mCRPC was assessed with incremental cost-effectiveness ratios ranging from dominance for mitoxantrone to $562,328 per quality-adjusted life year gained for sipuleucel-T compared with prednisone alone. Annual costs for the treatment of castration-resistant prostate cancer ranged from $3,067 to $77,725.

Conclusion

The cost-effectiveness of treatments of CRPC strongly depended on the willingness to pay per quality-adjusted life year gained/life-year saved throughout all included costs-effectiveness analyses and model-based economic evaluations. High-quality cost-effectiveness analyses based on randomized controlled trials are needed in order to make informed decisions on the management of castration-resistant prostate cancer and the resulting financial impact on the healthcare system.

Focal Salvage Treatment of Radiorecurrent Prostate Cancer: A Narrative Review of Current Strategies and Future Perspectives

Over the last decades, primary prostate cancer radiotherapy saw improving developments, such as more conformal dose administration and hypofractionated treatment regimens. Still, prostate cancer recurrences after whole-gland radiotherapy remain common, especially in patients with intermediate- to high-risk disease. The vast majority of these patients are treated palliatively with androgen deprivation therapy (ADT), which exposes them to harmful side-effects and is only effective for a limited amount of time. For patients with a localized recurrent tumor and no signs of metastatic disease, local treatment with curative intent seems more rational. However, whole-gland salvage treatments such as salvage radiotherapy or salvage prostatectomy are associated with significant toxicity and are, therefore, uncommonly performed. Treatments that are solely aimed at the recurrent tumor itself, thereby better sparing the surrounding organs at risk, potentially provide a safer salvage treatment option in terms of toxicity. To achieve such tumor-targeted treatment, imaging developments have made it possible to better exclude metastatic disease and accurately discriminate the tumor. Currently, focal salvage treatment is being performed with different modalities, including brachytherapy, cryotherapy, high-intensity focused ultrasound (HIFU), and stereotactic body radiation therapy (SBRT). Oncologic outcomes seem comparable to whole-gland salvage series, but with much lower toxicity rates. In terms of oncologic control, these results will improve further with better understanding of patient selection. Other developments, such as high-field diagnostic MRI and live adaptive MRI-guided radiotherapy, will further improve precision of the treatment.

Quality of life in men with metastatic prostate cancer in their final years before death - a retrospective analysis of prospective data

Background

Quality of Life (QoL) is the most important outcome for patients in palliative care along with symptom alleviation. Metastatic prostate cancer (mPC) is a life-threatening illness, and hence, a palliative care approach may be beneficial to this group. Over time, new life-prolonging treatments have been developed for men with mPC, but the possibility to prolong life should also be balanced against the men’s QoL, particularly because there are side effects involved with these treatments. The aim of this study was to evaluate QoL, functioning and symptoms in men with mPC during their final years before death.

Methods

This is a retrospective analysis of data from a long-term prospective study of men (n = 3885) with prostate cancer from two regions in Sweden. Validated questionnaires asking about participants’ QoL, functioning and symptoms were used to collect data. From the overall study, 190 men with mPC were identified. They were stratified into three groups, depending on the amount of time that had passed between the last questionnaire and their death; < 6 months, 6–18 months and > 18 months before death.

Results

Men with mPC generally rated their QoL poorly compared to established clinically significant threshold values. The group of men that were < 6 months before death rated their QoL, functioning and several symptoms significantly worse than the two other groups. Men that died after the year 2006 reported lower QoL and functioning and more pain and fatigue than those who died before 2006.

Conclusion

The results in this study indicate that men with mPC have unmet needs with regards to QoL and symptoms. A palliative care approach, alongside possible life-prolonging treatments, that focuses on QoL and symptom relief, may serve as an important frame to give the best support to these men in their final years of life.

Dendritic cells pulsed with prostate-specific membrane antigen in metastatic castration-resistant prostate cancer patients: a systematic review and meta-analysis

BACKGROUND

Dendritic cells (DCs) are used in many malignancies as vaccines to induce immunity against specific cancer antigens. The role of DCs in metastatic castration-resistant prostate cancer (mCRPC) is not determined. In this study, the proportion of mCRPC patients with clinically significant response to targeted therapy by DCs pulsed with prostate-specific membrane antigen was evaluated, and the possible adverse effects of this modality were investigated.

METHODS

Major databases were searched up to Feb 2017, to identify studies in which the antitumor efficacy of DCs pulsed with the extracellular portion of PSMA was studied for the treatment of mCRPC. Data were collected by two reviewers and analyzed using Comprehensive Meta-Analysis software, version 2.0.

FINDINGS

Our study consisted of 6 nonrandomized prospective (cohort) trials, overall reporting on 153 mCRPC patients. The event rate that is the representative of fraction of patients showing antitumor response was 0.43 (95% confidence interval = 0.355-0.512; P = 0.097). No significant between-study heterogeneity or inconsistency was detected (I2 = 5.47; Q = 5; P = 0.382). Our study failed to demonstrate a significant therapeutic efficacy for DCs in mCRPC. However, no significant adverse effects were seen.

Role of multiparametric magnetic resonance imaging for patients under active surveillance for prostate cancer: a systematic review with diagnostic meta-analysis

BACKGROUND

The use of multiparametric magnetic resonance imaging (mpMRI) in the setting of patients under active surveillance (AS) is promising. In this systematic-review we aimed to analyse the role of mpMRI in patients under AS.

METHODS

A comprehensive literature research for English-language original and review articles, recently published, was carried out using Medline, Scopus and Web of sciences databases until 30 October 2017. The following MeSH terms were used: 'active surveillance', 'prostate cancer', 'multiparametric magnetic resonance imaging'. A diagnostic meta-analysis was performed for 3.0 T mpMRI in predicting disease re-classification.

RESULTS

In total, 226 studies were selected after research and after removal of duplicates. After analysis on inclusion criteria, 43 studies were identified as eligible for this systematic review with a total of 6,605 patients. The timing of MRI during follow-up of AS differed from all studies like criteria for inclusion in the AS protocol. Overall, there was a low risk of bias across all studies. The diagnostic meta-analysis for 1.5 tesla showed a sensitivity of 0.60, negative predictive value (NPV) of 0.75 and a hierarchical summary receiving operating curve (HSROC) of 0.74 while for 3.0 tesla mpMRI a sensitivity of 0.81, a NPV of 0.78 and a HSROC of 0.83.

CONCLUSIONS

Overall, the available evidence suggests that both 1.5 or 3.0 Tesla mpMRI are a valid tool to monitor progression during AS follow-up, showing good accuracy capabilities in detecting PCa re-classification. However, the modality to better define what means 'disease progression' on mpMRI must be further evaluated.

Effect of early salvage radiotherapy at PSA < 0.5 ng/ml and impact of post-SRT PSA nadir in post-prostatectomy recurrent prostate cancer

BACKGROUND

For patients with recurrent prostate cancer after radical prostatectomy (RP), salvage radiotherapy (SRT) offers a second chance of cure. European guidelines (EAU) recommend SRT at a PSA < 0.5 ng/ml. We analyze the efficacy of SRT given according to this recommendation and investigate the predictive power of the post-SRT PSA nadir.

METHODS

Between 1998 and 2013, 301 patients of two university hospitals received SRT at a PSA < 0.5 ng/ml (median 0.192 ng/ml, IQR 0.110-0.300). Patients, who previously received androgen deprivation therapy, were excluded. All patients had 3D-conformal RT or intensity-modulated radiotherapy (IMRT, n = 59) (median 66.6 Gy). The median follow-up was 5.9 years. Progression and overall survival were the endpoints.

RESULTS

After SRT, 252 patients re-achieved an undetectable PSA. In univariate analysis, pre-RP PSA ≥ 10 ng/ml, pT3-4, Gleason score (GS) 7-10 or 8-10, negative surgical margins, post-RP PSA ≥ 0.1 ng/ml, pre-SRT PSA ≥ 0.2 ng/ml and post-SRT PSA nadir ≥ 0.1 ng/ml correlated unfavorably with post-SRT progression. In a multivariable Cox model, pT3-4, GS 7-10, negative margins and a pre-SRT PSA ≥ 0.2 ng/ml were significant risk factors. If the post-SRT PSA was added to the analysis, it dominated the outcome (HR = 9.00). Of the patients with a pre-SRT PSA < 0.2 ng/ml, only 9% failed re-achieving an undetectable PSA. Overall survival in these patients was 98% after 5.9 years compared to 91% in patients with higher pre-SRT PSA (Logrank p = 0.004).

CONCLUSIONS

SRT at a PSA < 0.2 ng/ml correlates significantly with achieving a post-SRT undetectable PSA (<0.1 ng/ml) and subsequently with improved freedom from progression. Given these overall favorable outcomes, whether additional androgen deprivation therapy is required for these men requires further study.

Retrospective Analysis of Patients With Prostate Cancer Initiating GnRH Agonists/Antagonists Therapy Using a German Claims Database: Epidemiological and Patient Outcomes

Objective: The objective of this study was to obtain real-world information on gonadotropin-releasing hormone agonist/antagonist (GnRHa) therapy in patients with advanced prostate cancer (PCa).

Materials and methods: Anonymized, routine healthcare claims data from approx. 75 German statutory health insurance funds from 2010–2015 (n = 4,205,227) were analyzed. Patients had an enrolment of 1 year before GnRHa, 1 index quarter of initial GnRHa prescription and ≥2 years of follow-up.

Results: In total, 2,382 patients with PCa were eligible. The most frequent index therapy was leuprolide in 56.6%. The rank order of PCa comorbidity prevalence was consistent over time (% at index and 3-years of follow-up): hypertension (71.5; 85.0), hyperlipidemia (45.2; 60.8), cardiovascular disease (CVD) (35.7; 54.1), and diabetes (28.3; 36.2). Comparing pooled therapy classes (agonists, hybrids, and antagonist), no significant differences in the incidence of CVD or diabetes were observed. For hypertension, there was a significant increase for agonists (16.4%) compared to antagonists (6.9%, p = 0.022) and leuprolide hybrid group (11.6%, p = 0.006). During the follow-up period 23.9% of all PCa patients died. There were no significant differences concerning mortality rate and discontinuation rates between the cohorts. In total, 11.2% of all patients discontinued GnRHa after first prescription; the mean time to first switch to another GnRHa therapy was 100 days earlier for hybrids than for agonists (p = 0.016).

Conclusion: This comparative retrospective analysis provides real-world information about healthcare characteristics and treatment patterns, highlighting the impact of different GnRHa on clinical outcomes for patients with advanced PCa in Germany.

Patient Selection for Radium-223 Therapy in Patients With Bone Metastatic Castration-Resistant Prostate Cancer: New Recommendations and Future Perspectives

Radium-223 therapy was registered in 2013 as a new life-prolonging therapeutic option for patients with symptomatic bone metastatic castration-resistant prostate cancer after the phase 3 ALSYMPCA study. Postregistration reports on the use of radium-223 in real-world populations demonstrate that appropriate selection of patients for radium-223 therapy is challenging. While primarily retrospective and post hoc studies identified prognostic variables associated with overall survival, validated predictive biomarkers are still lacking. Important pretherapeutic prognostic variables include the number of prior therapies, baseline Eastern Cooperative Oncology Group performance status, baseline extent of bone metastatic disease, and baseline alkaline phosphatase, prostate-specific antigen, and lactate dehydrogenase levels. We reviewed the currently available literature to provide recommendations on patient selection for radium-223 therapy in patients with bone metastatic castration-resistant prostate cancer. In addition, the recent evidence from the report of the European Medicines Agency's Pharmacovigilance Risk Assessment Committee regarding the restricted use of radium-223 after interim data analysis of the ERA-223 trial has been incorporated into our recommendations. Future perspectives are also discussed, including radium-223 re-treatment, the use of concomitant therapies, and the implementation of pretherapeutic molecular analysis for treatment stratification.

Remarkable response to abiraterone acetate in castration-resistant prostate cancer patient with aggressive liver metastasis

Introduction

The number of treatment options for metastatic castration-resistant prostate cancer has increased in recent years. Abiraterone, which selectively inhibits CYP17 in the androgen synthesis pathway, is widely used. Liver metastasis is one of the worst prognostic factors in metastatic castration-resistant prostate cancer. Only a few case reports have shown abiraterone successfully treated the liver metastasis of metastatic castration-resistant prostate cancer.

Case presentation

A 62-year-old man with prostate-specific antigen of 16.69 ng/mL was diagnosed with Gleason 8 (3 + 5) poorly differentiated prostate adenocarcinoma. Androgen deprivation therapy and sequential anti-androgen replacement were performed; however, the disease advanced to castration-resistant prostate cancer with liver metastasis. Prior to docetaxel, abiraterone achieved marked improvements in liver metastasis and prostate-specific antigen.

Conclusion

Metastatic castration-resistant prostate cancer patients with visceral metastasis were excluded from COU-AA-302, which is phase III trial on abiraterone prior to docetaxel. Although docetaxel is the recommended treatment for the visceral metastasis of castration-resistant prostate cancer according to the European Association of Urology guidelines, abiraterone also has potential as a treatment option.

Molecular underpinnings of enzalutamide resistance

Prostate cancer (PCa) is among the most common adult malignancies, and the second leading cause of cancer-related death in men. As PCa is hormone dependent, blockade of the androgen receptor (AR) signaling is an effective therapeutic strategy for men with advanced metastatic disease. The discovery of enzalutamide, a compound that effectively blocks the AR axis and its clinical application has led to a significant improvement in survival time. However, the effect of enzalutamide is not permanent, and resistance to treatment ultimately leads to development of lethal disease, for which there currently is no cure. This review will focus on the molecular underpinnings of enzalutamide resistance, bridging the gap between the preclinical and clinical research on novel therapeutic strategies for combating this lethal stage of prostate cancer.

18F-NaF/223RaCl2 theranostics in metastatic prostate cancer: treatment response assessment and prediction of outcome

Theranostics refers to companion agents with identical or similar structure targeted to a specific biological entity for imaging and treatment. Although the concept has a long history with radioiodine in thyroidology, but it has experienced remarkable recent renaissance in management of neuroendocrine tumors and prostate cancer. Bone scintigraphy based on osteoblastic reaction and targeted radionuclide therapy with the alpha-particle calcium-mimetic agent, 223RaCl2, also form a theranostic model for imaging and treatment of osseous metastatic disease. Since the regulatory approval of 223RaCl2 in 2013, there has been accumulating evidence on the potential use of 18F-NaF PET scintigraphy in the assessment of response and prediction of outcome in males with metastatic castrate-resistant prostate cancer who undergo 223RaCl2 therapy. We review the 18F-NaF/223RaCl2 as theranostic companion in the management of prostate cancer with emphasis on the utility of 18F-NaF and other relevant PET radiotracers in the therapy response and prognosis assessments.

Impact of sodium 18F-fluoride PET/CT, 18F-fluorocholine PET/CT and whole-body diffusion-weighted MRI on the management of patients with prostate cancer suspicious for metastasis: a prospective multicentre study

PURPOSE

To compare the impact of 18F-sodium-fluoride (NaF) PET/CT, 18F-fluorocholine (FCH) PET/CT and diffusion-weighted whole-body MRI (DW-MRI) on the management of patients with prostate cancer (PCa) suspicious for distant metastasis.

METHODS

Prostate cancer patients were prospectively included between December 2011 and August 2014 and benefited from these three whole-body imaging (WBI) modalities within 1 month in addition to the standard PCa workup. Management was prospectively decided by clinicians during two multidisciplinary meetings, before and after the whole-body imaging workup. Rates of induced changes of whole-body imaging modalities were compared by Cochran's Q test.

RESULTS

One-hundred-one patients (27 at staging, 59 at first biochemical recurrence (BCR) and 15 at first episode of rising serum level of prostate-specific antigen during androgen-deprivation therapy) were included. The overall rate of management changes was 52%: 29% as a consequence of WBI, higher for FCH-PET/CT than for NaF-PET/CT or DW-MRI (p < 0.0001) and highest (41%) for FCH-PET/CT at BCR. Actual management was adequate in all patients but two.

CONCLUSIONS

Whole-body imaging induced a change in management in approximately a third of PCa patients suspicious for metastasis. The impact rate was determined to be greatest at first BCR using FCH-PET/CT. NaF-PET/CT and DW-MRI seemed less useful in this context.

Current therapeutic options in metastatic castration-resistant prostate cancer

BACKGROUND

The tumors of many patients with prostate cancer eventually become refractory to androgen deprivation therapy with progression to metastatic castration-resistant disease. Significant advances in the treatment of metastatic castration-resistant prostate cancer (mCRPC) have been made in recent years, and new treatment strategies have recently been made available. The aim of this report was to schematically review all the approved pharmacologic treatment options for patients with mCRPC through 2018, analyzing the efficacy and possible side effects of each therapy to assist clinicians in reaching an appropriate treatment decision. New biomarkers potentially of aid in the choice of treatment in this setting are also briefly reviewed.

METHODS

We performed a literature search of clinical trials of new drugs and treatments for patients diagnosed with mCRPC published through 2018.

RESULTS

Two new hormonal drugs, abiraterone acetate and enzalutamide have been approved by FDA in 2011 and 2012, respectively for the treatment of patients with mCRPC and have undergone extensive testing. While these treatments have shown a benefit in progression-free and overall survival, the appropriate sequencing must still be determined so that treatment decisions can be made based on their specific clinical profile. Cabazitaxel has been shown to be an efficient therapeutic option in a postdocetaxel setting, while its role in chemotherapy-naïve patients must still be determined. Sipuleucel-T and radium-223 have been studied in patients without visceral metastases and have achieved overall survival benefits with good safety profiles. The feasibility and efficacy of combinations of new treatments with other known therapies such as chemotherapy are currently under investigation.

CONCLUSIONS

Drug development efforts continue to attempt to prolong survival and improve quality of life in the mCRPC setting, with several therapeutic options available. Ongoing and future trials are needed to further assess the efficacy and safety of these new drugs and their interactions, along with the most appropriate sequencing.

A Territory-wide, Multicenter, Age- and Prostate-specific Antigen-matched Study Comparing Chemohormonal Therapy and Hormonal Therapy Alone in Chinese Men With Metastatic Hormone-sensitive Prostate Cancer

BACKGROUND

There is a lack of real-world data regarding the treatment outcomes of chemohormonal therapy versus hormonal therapy alone in Chinese men with metastatic hormone-sensitive prostate cancer.

PATIENTS AND METHODS

We conducted a territory-wide, multicenter, age- and prostate-specific antigen (PSA)-matched cohort study comparing chemohormonal therapy and hormonal therapy alone in Chinese men with metastatic hormone-sensitive prostate cancer. Patient and disease characteristics were reviewed. The primary outcome was PSA progression-free survival. Secondary outcomes included clinical progression-free survival and castration resistance-free survival. Kaplan-Meier and multivariate Cox regression analyses were performed.

RESULTS

From January 2015 to July 2016, 32 Chinese men with metastatic hormone-sensitive prostate cancer were treated with chemohormonal therapy, and they were matched to 32 Chinese men who were treated with hormonal therapy alone. Patient and disease characteristics were similar between the 2 groups. The chemohormonal therapy group had a significantly better PSA progression-free survival (P = .001) and castration resistance-free survival (P = .002) than the hormonal therapy group. There was no significant difference in the clinical progression-free survival between the 2 groups. Upon multivariate Cox regression analyses, the use of chemohormonal therapy was significantly associated with a longer time to PSA progression (hazard ratio, 0.31; 95% confidence interval, 0.31-0.73; P = .008) and a longer time to castration resistance (hazard ratio, 0.38; 95% confidence interval, 0.17-0.83; P = .015), but was not associated with clinical progression.

CONCLUSIONS

The use of chemohormonal therapy could prevent PSA progression and the development of castration resistance when compared with hormonal therapy alone in Chinese men with metastatic hormone-sensitive prostatic cancer.

LXRs, SHP, and FXR in Prostate Cancer: Enemies or Ménage à Quatre With AR?

Androgens and androgen receptor (AR, NR3C4) clearly play a crucial role in prostate cancer progression. Besides, the link between metabolic disorders and the risk of developing a prostate cancer has been emerging these last years. Interestingly, “lipid” nuclear receptors such as LXRα/NR1H3 and LXRβ/NR1H2 (as well as FXRα/NR1H4 and SHP/NR0B2) have been described to decrease the lipid metabolism, while AR increases it. Moreover, these former orphan nuclear receptors can regulate androgen levels and modulate AR activity. Thus, it is not surprising to find such receptors involved in the physiology of prostate. This review is focused on the roles of liver X receptors (LXRs), farnesoid X receptor (FXR), and small heterodimeric partner (SHP) in prostate physiology and their capabilities to interfere with the androgen-regulated pathways by modulating the levels of active androgen within the prostate. By the use of prostate cancer cell lines, mice deficient for these nuclear receptors and human tissue libraries, several authors have pointed out the putative possibility to pharmacologically target these receptors. These data open a new field of research for the development of new drugs that could overcome the castration resistance in prostate cancer, a usual phenomenon in patients.

Taxane-based chemohormonal therapy for metastatic hormone-sensitive prostate cancer

BACKGROUND

There has been considerable development in the treatment of advanced prostate cancer over the last decade. A number of agents, including docetaxel, cabazitaxel, abiraterone acetate, enzalutamide and sipuleucel-T, have been reported to improve outcomes in men with castration-resistant disease and their use is being explored in hormone-sensitive prostate cancer.

OBJECTIVES

To assess the effects of early taxane-based chemohormonal therapy for newly diagnosed, metastatic, hormone-sensitive prostate cancer.

SEARCH METHODS

We performed a comprehensive search using multiple databases (the Cochrane Library, MEDLINE, Embase, Scopus, Google Scholar, and Web of Science), trials registries, other sources of grey literature, and conference proceedings, up to 10 August 2018. We applied no restrictions on publication language or status.

SELECTION CRITERIA

We included randomized or quasi-randomized controlled trials in which participants were administered taxane-based chemotherapy with systemic androgen deprivation therapy (ADT) within 120 days of beginning ADT versus ADT alone at the time of diagnosis of metastatic disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently classified studies and abstracted data from the included studies. We performed statistical analyses using a random-effects model. We rated the quality of evidence according to the GRADE approach.

MAIN RESULTS

The search identified three studies in which 2,261 participants were randomized to receive either ADT alone, or taxane-based chemotherapy at a dose of 75mg per square meter of body surface area at three-weekly intervals for six or nine cycles in addition to ADT.Primary outcomesEarly treatment with taxane-based chemotherapy in addition to ADT probably reduces death from any cause compared to ADT alone (hazard ratio (HR) 0.77, 95% confidence interval (CI) 0.68 to 0.87; moderate-certainty evidence); this would result in 94 fewer deaths per 1,000 men (95% CI 51 to 137 fewer deaths). We downgraded the certainty of evidence due to study limitations related to potential performance bias. Based on the results of one study with 375 participants, the addition of taxane-based chemotherapy to ADT may increase the incidence of Grade III to V adverse events compared to ADT alone (risk ratio (RR) 2.98, 95% CI 2.19 to 4.04; low-certainty evidence); this would result in 405 more Grade III to V adverse events per 1,000 men (95% CI 243 to 621 more events). We downgraded the certainty of evidence due to study limitations and imprecision.Secondary outcomesEarly taxane-based chemotherapy in addition to ADT probably reduces the risk of prostate cancer-specific death (RR 0.79, 95% CI 0.70 to 0.89; moderate-certainty evidence). We downgraded the certainty of evidence due to study limitations related to potential performance and detection bias. The addition of taxane-based chemotherapy also probably reduces disease progression compared to ADT alone (HR 0.63, 95% CI 0.56 to 0.71; moderate-certainty evidence). We downgraded the certainty of evidence because of study limitations related to potential performance bias. The addition of taxane-based chemotherapy to ADT may result in a large increase in the risk of treatment discontinuation due to adverse events (RR 79.41, 95% CI 4.92 to 1282.78; low-certainty evidence). We downgraded the certainty of evidence due to study limitations and imprecision. This estimate is derived from a single study with no events in the control arm but a discontinuation rate of 20% in the intervention arm. Taxane-based chemotherapy may increase the incidence of adverse events of any grade (RR 1.11, 95% CI 1.06 to 1.17; low-certainty evidence). We downgraded our assessment of the certainty of evidence due to very serious study limitations. There may be a small improvement, which may not be clinically important, in quality of life at 12 months with combination treatment (mean difference (MD) 2.85 on the Functional Assessment of Cancer Therapy-Prostate scale, 95% CI 0.13 higher to 5.57 higher; low-certainty evidence). We downgraded the certainty of evidence for study limitations related to potential performance, detection and attrition bias.

AUTHORS' CONCLUSIONS

Compared to ADT alone, the early (within 120 days of beginning ADT) addition of taxane-based chemotherapy to ADT for hormone-sensitive prostate cancer probably prolongs both overall and disease-specific survival and delays disease progression. There may be an increase in toxicity with taxane-based chemotherapy in combination with ADT. There may also be a small, clinically unimportant improvement in quality of life at 12 months with taxane-based chemotherapy and ADT treatment.

Single-Fraction Stereotactic Body Radiotherapy for Oligometastatic Lymph Node Relapse in Prostate Cancer

BACKGROUND

Stereotactic body radiotherapy (SBRT) emerged as a treatment option in oligometastatic (≤3 metastases) patients experiencing lymph node relapse from treated prostate cancer. No recommendations are available concerning dose schedule, and available studies report the use of multiple-fraction regimens due to theoretical lower toxicity and higher cumulative dose delivered to the target. The aim of the present study was to evaluate the safety and efficacy of a dose-intensive, single-fraction SBRT regimen.

PATIENTS AND METHODS

Retrospective data on outcome and toxicity from 27 treatments on 23 consecutive patients were collected. Statistical analysis was performed.

RESULTS

Median follow-up was 22 months (range 6-63, interquartile range 15-28). Biochemical progression-free survival (bPFS) at 6 months, 1 year, and 2 years were 65%, 40%, and 26%, respectively. In 2 cases acute toxicity of grade 1 were observed.

CONCLUSION

Single-fraction SBRT for lymph node relapse of oligometastatic prostate cancer resulted in promising biochemical control with minimal toxicity.

Consensus on management of castration-resistant prostate cancer on behalf of the Urological Tumours Working Group (URONCOR) of the Spanish Society of Radiation Oncology

BACKGROUND

The knowledge in the field of castration-resistant prostate cancer (CRPC) is developing rapidly, with emerging new therapies and advances in imaging. Nonetheless, in multiple areas there is still a lack of or very limited evidence, and clear guidance from clinicians regarding optimal strategy is required.

METHODS

A modified Delphi method, with 116 relevant questions divided into 7 different CRPC management topics, was used to develop a consensus statement by the URONCOR group.

RESULTS

A strong consensus or unanimity was reached on 93% of the proposed questions. The seven topics addressed were: CRPC definition, symptomatic patients, diagnosis of metastasis, CRPC progression, M0 management, M1 management and sequencing therapy, and treatment monitoring.

CONCLUSIONS

The recommendations based on the radiation oncology experts' opinions are intended to provide cancer specialists with expert guidance and to standardise CRPC patient management in Spain, facilitating decision-making in different clinically relevant issues regarding CRPC patients.

Identifying the Optimal Candidate for Salvage Lymph Node Dissection for Nodal Recurrence of Prostate Cancer: Results from a Large, Multi-institutional Analysis

BACKGROUND

Salvage lymph node dissection (SLND) represents a possible treatment option for prostate cancer patients affected by nodal recurrence after local treatment. However, SLND may be associated with intra- and postoperative complications, and the oncological benefit may be limited to specific groups of patients.

OBJECTIVE

To identify the optimal candidates for SLND based on preoperative characteristics.

DESIGN, SETTING, AND PARTICIPANTS

The study included 654 patients who experienced prostate-specific antigen (PSA) rise and nodal recurrence after radical prostatectomy (RP) and underwent SLND at nine tertiary referral centers. Lymph node recurrence was documented by positron emission tomography/computed tomography (PET/CT) scan using either ¹¹C-choline or ⁶⁸Ga-labeled prostate-specific membrane antigen ligand.

INTERVENTION

SLND.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The study outcome was early clinical recurrence (eCR) developed within 1 yr after SLND. Multivariable Cox regression analysis was used to develop a predictive model. Multivariable-derived coefficients were used to develop a novel risk calculator. Decision-curve analysis was used to evaluate the net benefit of the predictive model.

RESULTS AND LIMITATIONS

Median follow-up was 30 (interquartile range, 16-50) mo among patients without clinical recurrence (CR), and 334 patients developed CR after SLND. In particular, eCR at 1 yr after SLND was observed in 150 patients, with a Kaplan-Meier probability of eCR equal to 25%. The development of eCR was significantly associated with an increased risk of cancer-specific mortality at 3 yr, being 20% versus 1.4% in patients with and without eCR, respectively (p<0.0001). At multivariable analysis, Gleason grade group 5 (hazard ratio [HR]: 2.04; p<0.0001), time from RP to PSA rising (HR: 0.99; p=0.025), hormonal therapy administration at PSA rising after RP (HR: 1.47; p=0.0005), retroperitoneal uptake at PET/CT scan (HR: 1.24; p=0.038), three or more positive spots at PET/CT scan (HR: 1.26; p=0.019), and PSA level at SLND (HR: 1.05; p<0.0001) were significant predictors of CR after SLND. The coefficients of the predictive model were used to develop a risk calculator for eCR at 1 yr after SLND. The discrimination of the model (Harrel'sC index) was 0.75. At decision-curve analysis, the net benefit of the model was higher than the "treat-all" option at all the threshold probabilities.

CONCLUSIONS

We reported the largest available series of patients treated with SLND. Roughly 25% of men developed eCR after surgery. We developed the first risk stratification tool to identify the optimal candidate to SLND based on routinely available preoperative characteristics. This tool can be useful to avoid use of SLND in men more likely to progress despite any imaging-guided approach.

PATIENT SUMMARY

The risk of early recurrence after salvage lymph node dissection (SLND) was approximately 25%. In this study, we developed a novel tool to predict the risk of early failure after SLND. This tool will be useful to identify patients who would benefit the most from SLND from other patients who should be spared from surgery.

Metastases-yield and Prostate-specific Antigen Kinetics Following Salvage Lymph Node Dissection for Prostate Cancer: A Comparison Between Conventional Surgical Approach and Prostate-specific Membrane Antigen-radioguided Surgery

The first results on ^99mTechnetium prostate-specific membrane antigen-radioguided surgery (^99mTc-PSMA- RGS) showed promising outcome. Here, we sought to evaluate if this targeted molecular surgical approach might be more effective than conventional salvage lymph node dissection (sLND). We prospectively analysed 42 consecutive patients who underwent sLND based on preoperative ⁶⁸Gallium (⁶⁸Ga)-PSMA-positron emission tomography (PET) imaging between 2015 and 2018. In 29 patients, the dissection field was based solely ⁶⁸Ga-PSMA-PET imaging (conventional surgical approach [CSA]), whereas 13 patients underwent ^99mTc-PSMA-RGS. Preoperative characteristics of both groups were similar. Final pathology revealed no metastases in nine CSA patients (31%), whereas all visible lesions on preoperative ⁶⁸Ga-PSMA-PET were removed in patients who underwent RGS. A PSA decline in general, >50% and >90% within 6 wk was seen in 50%, 29%, and 7% versus 100%, 92%, and 53% in CSA versus RGS groups, respectively (all p<0.01). This is the first comparison of conventional and PSMA-radioguided approach with regards to short-term efficacy of sLND. Although long-term outcome needs to be awaited, RGS offers promising results. PATIENT SUMMARY: We compared two surgical approaches for lymph node dissection in lymph node only recurrent prostate cancer patients. The radioguided approach was superior in removing the affected lymph nodes, resulting in a more pronounced prostate-specific antigen decline.

Combining anticancer drugs with osteoprotective agents in prostate cancer-A contemporary update

Recently, a plethora of life-prolonging cytotoxic, next-generation hormonal, immunotherapeutical as well as radionuclide therapies has emerged as a standard care for metastasized castration-resistant prostate cancer. Being strikingly effective in cancer control, these novel therapies might in fact exert a beneficial impact on skeletal events. Therefore, combining anticancer drugs with osteoprotective agents might lead to additional clinical advantage but must be weighed against simultaneously exposing patients to serious toxicities. In addition, further survival prolongation by changing treatment paradigm in both metastasized hormone-sensitive and nonmetastatic castration-resistant disease might potentially increase the risk for bone density reduction complications due to a growing efficacy of androgen ablation leading to prolonged exposure. To address both possible indications of combined treatment and to draw practical conclusions, we performed a comprehensive review of the currently available evidence.

Effect on Survival of Androgen Deprivation Therapy Alone Compared to Androgen Deprivation Therapy Combined with Concurrent Radiation Therapy to the Prostate in Patients with Primary Bone Metastatic Prostate Cancer in a Prospective Randomised Clinical Trial: Data from the HORRAD Trial

BACKGROUND

The cornerstone of standard treatment for patients with primary bone metastatic prostate cancer (mPCa) is androgen deprivation therapy (ADT). Retrospective studies suggest a survival benefit for treatment of the primary prostatic tumour in mPCa, but to date, no randomised-controlled-trials (RCTs) have been published addressing this issue.

OBJECTIVE

To determine whether overall survival is prolonged by adding local treatment of the primary prostatic tumour with external beam radiation therapy (EBRT) to ADT.

DESIGN, SETTING, AND PARTICIPANTS

The HORRAD trial is a multicentre RCT recruiting 432 patients with prostate-specific antigen (PSA) >20ng/ml and primary bone mPCa on bone scan between 2004 and 2014.

INTERVENTION

Patients were randomised to either ADT with EBRT (radiotherapy group) or ADT alone (control group).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Primary endpoint was overall survival. Secondary endpoint was time to PSA progression. Crude and adjusted analyses were applied to evaluate treatment effect.

RESULTS AND LIMITATIONS

Median PSA level was 142ng/ml and 67% of patients had more than five osseous metastases. Median follow up was 47 mo. Median overall survival was 45 mo (95% confidence interval [CI], 40.4-49.6) in the radiotherapy group and 43 mo (95% CI: 32.6-53.4) in the control group (p=0.4). No significant difference was found in overall survival (hazard ratio [HR]: 0.90; 95% CI: 0.70-1.14; p=0.4). Median time to PSA progression in the radiotherapy group was 15 mo (95% CI: 11.8-18.2), compared with 12 mo (95% CI: 10.6-13.4) in the control group. The crude HR (0.78; 95% CI: 0.63-0.97) was statistically significant (p=0.02).

CONCLUSIONS

The current RCT comparing ADT to ADT with EBRT to the prostate in patients with primary bone mPCa did not show a significant difference in overall survival, although the CI cannot exclude a substantial survival benefit. Further research is needed to confirm our findings.

PATIENT SUMMARY

This study investigated the effect of adding radiation therapy to the prostate to hormonal therapy in prostate cancer patients with metastasis to the bone at diagnosis. In our patient group, additional radiotherapy did not improve overall survival. Further research is needed to confirm our findings.

TWITTER SUMMARY

Adding radiotherapy to the prostate in patients with bone metastatic prostate cancer does not improve overall survival.

Importance of androgen-deprivation therapy during enzalutamide treatment in men with metastatic castration-resistant prostate cancer following chemotherapy: results from retrospective, multicenter data

BACKGROUND

Enzalutamide can significantly prolong the survival of patients with metastatic castration-resistant prostate cancer (mCRPC). However, there is a paucity of evidence on continuing androgen-deprivation therapy (ADT) for mCRPC. Here, we analyzed the effect of concomitant ADT during enzalutamide treatment in men with mCRPC following chemotherapy.

METHODS

We retrospectively reviewed the medical records of 232 patients with mCRPC who received oral enzalutamide (160 mg per day) following chemotherapy at 9 tertiary centers in Korea between 2014 and 2016. The primary endpoint was overall survival, while secondary endpoints included time to prostate-specific antigen (PSA) progression and radiographic progression-free survival.

RESULTS

The median age of the patients was 71 years (interquartile range, 64-75 years). The proportion of patients in a grade group ≥4 was 77.6%. The rate of concomitant ADT was 29.3%, and the all-cause mortality rate was 27.1% (n = 63). Median overall survival, time to PSA progression, and radiographic progression-free survival were 24.0, 8.0, and 10.0 months, respectively. Notably, concomitant ADT showed a significant association with longer overall survival (median duration not reached vs. 18.2 months; p = 0.008). After adjusting for confounding factors, concomitant ADT was still associated with longer overall survival (hazard ratio, 0.35; 95% confidence interval, 0.17-0.72).

CONCLUSION

Concomitant ADT during enzalutamide treatment may improve the survival of patients with mCRPC following chemotherapy.

Low-frequency ultrasound enhances chemotherapy sensitivity and induces autophagy in PTX-resistant PC-3 cells via the endoplasmic reticulum stress-mediated PI3K/Akt/mTOR signaling pathway

Background

Sonodynamic therapy (SDT) is an emerging tumor-inhibiting method that has gained attention in cancer therapy in the last several years. Although autophagy has been observed in SDT-treated cancer cells, its role and mechanism of action remain unclear. This study aimed to investigate the effects of low-frequency ultrasound on autophagy and drug-resistance of paclitaxel (PTX)-resistant PC-3 cells via the endoplasmic reticulum stress (ERs)-mediated PI3K/AT/mTOR signaling pathway.

Methods

CCK-8 assay was conducted to select the appropriate exposure time for PTX-resistant PC-3 cells under low-frequency ultrasound. PTX-resistant PC-3 cells were divided into a control group, PTX group, ultrasound group, ultrasound + PTX group, ultrasound + PTX + autophagy-related gene 5 (Atg5) siRNA group, and ultrasound + 4-PBA (an ERs inhibitor) group. Autophagy was observed by transmission electron microscopy (TEM) and fluorescence microscopy. Cell proliferation was evaluated using CCK-8 assay; apoptosis was detected by flow cytometry. Expression of multiple drug-resistance genes was detected by qRT-PCR. Western blotting was used to detect the expression of ERS-related proteins, autophagy-related proteins, apoptosis-related proteins, and PI3K/AKT/mTOR pathway-related proteins.

Results

Ten-second exposure was selected as optimal for all experiments. Compared to the PTX group, the level of autophagy, inhibition rate, apoptosis rate, and expression of ERS-related proteins (GRP78) increased, whereas the expression of multiple drug-resistance genes (MRP3, MRP7, and P-glycoprotein), PI3K/AKT/mTOR pathway-related proteins (PI3K, p-AKT, mTORC1), and apoptosis-related proteins (Bcl-2, NF-κB) decreased in PTX-resistant PC-3 cells after low-frequency ultrasound and PTX treatment for 24 h. These trends were more obvious after treatment with Atg5 siRNA, excluding the autophagy level. Post 4-PBA-treatment, the expression of GRP78 and LC3II proteins decreased, whereas that of PI3K, p-AKT, and mTORC1 increased.

Conclusion

Results indicated that ultrasound induces autophagy by ERs-mediated PI3K/AKT/mTOR signaling pathway in PTX-resistant PC-3 cells; this autophagy acts as a cytoprotector during low-frequency ultrasound-mediated reversal of drug resistance.

Prospective Immunophenotyping of CD8+ T Cells and Associated Clinical Outcomes of Patients With Oligometastatic Prostate Cancer Treated With Metastasis-Directed SBRT

PURPOSE

This study examined the effects of metastasis-directed stereotactic body radiation therapy (mdSBRT) on CD8⁺ T-cell subpopulations and correlated post-mdSBRT immunophenotypic responses with clinical outcomes in patients with oligometastatic prostate cancer (OPCa).

METHODS AND MATERIALS

Peripheral blood mononuclear cells were prospectively isolated from 37 patients with OPCa (≤3 metastases) who were treated with mdSBRT. Immunophenotyping identified circulating CD8⁺ T-cell subpopulations, including tumor-reactive (T_TR), effector memory, central memory (T_CM), effector, and naïve T cells from samples collected before and after mdSBRT. Univariate Cox proportional hazards regression was used to assess whether changes in these T-cell subpopulations were potential risk factors for death and/or progression. The Kaplan-Meier method was used for survival. Cumulative incidence for progression and new distant metastasis weas estimated, considering death as a competing risk.

RESULTS

Median follow-up was 39 months (interquartile range, 34-43). Overall survival at 3 years was 78.2%. Cumulative incidence for local progression and new distant metastasis at 3 years was 16.5% and 67.6%, respectively. Between baseline and day 14 after mdSBRT, an increase in the T_CM cell subpopulation was associated with the risk of death (hazard ratio, 1.22 [95% confidence interval, 1.02-1.47]; P = .033), and an increase in the T_TR cell subpopulation was protective against the risk of local progression (hazard ratio, 0.80 [95% confidence interval, 0.65-0.98]; P = .032).

CONCLUSIONS

An increase in the T_TR cell subpopulation was protective against the risk of disease progression, and an increase in the T_CM cell subpopulation was associated with the risk of death in patients with OPCa treated with mdSBRT. Disease control may be further improved by better understanding the CD8⁺ T-cell subpopulations and by enhancing their antitumor effect.

Diagnostic Performance of 18F-Fluciclovine in Detection of Prostate Cancer Bone Metastases

PURPOSE

F-fluciclovine is a synthetic amino acid radiotracer that has recently been approved in Europe and the United States for PET imaging in men with biochemical recurrence (BCR) of prostate cancer after prior definitive treatment. Accurate identification of the sites of disease in patients presenting with BCR of prostate cancer is important in determining the appropriate treatment. Bone is the most frequent site of metastatic disease in patients with prostate cancer.

METHODS

We conducted a comprehensive review of the available preclinical and clinical data on the diagnostic performance of F-fluciclovine PET/CT in an attempt to draw practical and general conclusions on the utility and limitations of F-fluciclovine PET/CT in localization of osseous metastatic disease in prostate cancer.

RESULTS

The cumulative preclinical data and results of some retrospective and 2 prospective clinical studies suggest that F-fluciclovine can detect early bone marrow involvement in patients with BCR of prostate cancer and negative prior bone-specific imaging findings.

CONCLUSIONS

F-fluciclovine PET/CT seems to offer useful information for early detection of bone metastases in men with BCR of prostate cancer. Additional investigations will be needed to compare the diagnostic performance of F-fluciclovine PET/CT to other standard and novel imaging methods in initial staging, BCR, and castrate-resistant phases of disease.

Diagnostic performance of choline PET/CT for the detection of bone metastasis in prostate cancer: A systematic review and meta-analysis

Purpose

The aim of this study was to evaluate the diagnostic performance of choline positron emission tomography/computed tomography (PET/CT) for the detection of bone metastasis in patients with prostate cancer.

Methods

MEDLINE, EMBASE and the Cochrane Library were searched up to 20 February 2018 for studies that used 11C-choline or 18F-choline PET/CT for the detection of bone metastasis in patients with prostate cancer and “histopathology and/or clinical follow-up” as the reference standard. Methodological quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Pooled diagnostic accuracy with the 95% confidence interval (CI) was calculated using a bivariate random effects model. We also constructed hierarchical summary receiver operating characteristic curves and performed meta-regression analyses.

Results

Fourteen studies with reasonable methodological quality were included in the analysis. On a per-patient basis, the pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were 0.89 (95% CI 0.80–0.94), 0.98 (95% CI 0.95–0.99), 40.4 (95% CI 19.7–82.6), 0.12 (95% CI 0.07–0.20), and 344 (95% CI 148–803), respectively. On a per-lesion basis, the pooled sensitivity, specificity, PLR, NLR, and DOR were 0.91 (95% CI 0.85–0.94), 0.97 (95% CI 0.95–0.98), 34.1 (95% CI 20.0–58.1), 0.10 (95% CI 0.06–0.16), and 358 (95% CI 165–778), respectively. In the meta-regression analysis, the clinical setting (staging vs. restaging) was the only source of study heterogeneity on a per-patient basis.

Conclusions

Choline PET/CT shows excellent diagnostic performance for the detection of bone metastasis. However, a negative choline PET/CT result cannot ensure the lack of bone metastasis.

Stereotactic ablative radiation therapy for oligometastatic prostate cancer delays time-to-next systemic treatment

PURPOSE

Local ablative treatment to oligometastatic patients can result in long-term disease-free survival in some cancer patients. The importance of this treatment paradigm in prostate cancer is a rapidly evolving field. Herein, we report on the safety and preliminary clinical outcomes of a modern cohort of oligometastatic prostate cancer (OPC) patients treated with consolidative stereotactic ablative radiation (SABR).

METHODS

Records of men with OPC who underwent consolidative SABR at our institution were reviewed. SABR was delivered in 1-5 fractions of 5-18 Gray. Kaplan-Meier estimates of local progression-free survival (LPFS), biochemical progression-free survival (bPFS; PSA nadir + 2), distant progression-free survival (DPFS), and time-to-next intervention (TTNI) were calculated.

RESULTS

In total, 66 OPC patients were identified with consolidative SABR delivered to 134 metastases: 89 bone, 40 nodal, and 5 viscera. The majority of men (49/66) had hormone-sensitive prostate cancer (HSPC). Crude grade 1 and 2 acute toxicities were 36% and 11%, respectively, with no ≥ grade 3 toxicity. At 1 year, LPFS was 92% and bPFS and DPFS were 69%. Of the 18 men with HSPC who had deferred hormone therapy , 11 (56%) remain disease free following SABR (1-year ADT-FS was 78%). In 17 castration-resistant men, 11 had > 50% prostate-specific antigen (PSA) declines with 1-year TTNI of 30%.

CONCLUSIONS

Consolidative SABR in OPC is feasible and well tolerated. The heterogeneity and small size of our series limit extrapolation of clinically meaningful outcomes following consolidative SABR in OPC, but our preliminary data suggest that this approach warrants continued prospective study.

Number-needed-to-treat analysis of clinical progression in patients with metastatic castration-resistant prostate cancer in the STRIVE and TERRAIN trials

BACKGROUND

This analysis estimated the number needed to treat with enzalutamide versus bicalutamide to achieve one additional patient with chemotherapy-naïve metastatic castration-resistant prostate cancer who would obtain clinical benefit regarding progression-free survival, radiographic progression-free survival, or no prostate-specific antigen progression at 1 and 2 years following treatment initiation.

METHODS

Clinical event rates were obtained from the STRIVE (NCT01664923) and TERRAIN (NCT01288911) trials, and the number needed to treat was the inverse of the absolute rate difference between the event rates of enzalutamide and bicalutamide. The 95% Confidence Interval of the number needed to treat was derived from the 95% Confidence Interval of the event rate difference.

RESULTS

Using STRIVE data (patients with metastatic disease: n = 128 enzalutamide; n = 129 bicalutamide) comparing enzalutamide with bicalutamide at 1 and 2 years, the numbers needed to treat to achieve one additional patient with chemotherapy-naïve metastatic castration-resistant prostate cancer with progression-free survival were 2.0 and 2.8, respectively; with radiographic progression-free survival, 2.6 and 3.0, respectively; and without prostate-specific antigen progression, 1.8 and 2.4, respectively. Using TERRAIN data (n = 184 enzalutamide; n = 191 bicalutamide) comparing enzalutamide with bicalutamide at 1 and 2 years, the numbers needed to treat to achieve one additional patient with progression-free survival were 4.3 and 3.7, respectively; with radiographic progression-free survival, 10.0 and 2.8, respectively; and without prostate-specific antigen progression, 2.1 and 3.2, respectively.

CONCLUSIONS

The combined data from TERRAIN and STRIVE demonstrated that treating chemotherapy-naïve metastatic castration-resistant prostate cancer with enzalutamide leads to more patients without clinical progression at 1 and 2 years than with bicalutamide.

TRIAL REGISTRATION

STRIVE (NCT01664923; registration date: August 10, 2012) and TERRAIN (NCT01288911; registration date: February 1, 2011).

Predictive value of combined analysis of pro-NPY and ERG in localized prostate cancer

This study aimed to investigate if combined analysis of pro-Neuropeptide Y (NPY) and ERG expression in tumor tissue are associated with biochemical failure (BF), castration-based treatment, castration-resistant prostate cancer (CRPC), and prostate cancer (PCa)-specific death for men undergoing radical prostatectomy (RP) for PCa. This study included 315 patients, who underwent RP from 2002 to 2005. Both pro-NPY and ERG expression were analyzed using immunohistochemistry and were scored as low or high and negative or positive, respectively. Risk of BF, castration-based treatment, CRPC, and PCa-specific death were analyzed with multiple cause-specific Cox regression analyses and stratified cumulative incidences using competing risk assessment. Median follow-up was 13.0 years (95% CI: 12.7-13.2). In total, 85.7% were pro-NPY high and 14.3% were pro-NPY low. The combined analyses of pro-NPY and ERG expression was not associated with risk of BF (p = 0.7), castration-based treatment (p = 0.8), CRPC (p = 0.4) or PCa-specific death (p = 0.5). In the multiple cause-specific Cox regression analysis, pro-NPY high and ERG positivity was not associated with BF (HR: 1.02; 95% CI 0.6-1.7; p = 0.94). In conclusion the combination of pro-NPY and ERG expression did not show association with risk of BF, castration-based treatment, CRPC, and PCa-specific death following RP.

Risk of secondary rectal cancer and colon cancer after radiotherapy for prostate cancer: a meta-analysis

PURPOSE

To investigate whether radiotherapy for prostate cancer increases the risk of therapy-related rectal cancer and colon cancer.

METHODS

A systematic literature search was carried out using the Medline (PubMed), EMBASE, and the Cochrane Library to identify studies examining the association between radiotherapy for prostate cancer and secondary colorectal cancer (rectal cancer and colon cancer) published before March 19, 2018. The risk of second colorectal cancer after radiotherapy was summarized using unadjusted odds ratio (OR) and adjusted hazard ratio (HR) with their 95% confidence interval (CI). Subgroup and sensitivity analyses were conducted to detect potential bias and heterogeneity.

RESULTS

After study selection, 16 reports were retrieved for analysis. When patients received radiotherapy compared with those unexposed to radiation, there was an increased risk of the rectal cancer (OR 1.37, 95%CI 1.01 to 1.85), but not colon cancer. According to adjusted HR, there was an increased risk of the rectal cancer (HR 1.64, 95%CI 1.39 to 1.94), and colon cancer (HR 1.33, 95%CI 1.02 to 1.76). The OR for rectal cancer showed an increased risk with longer latent period (5 years lag time versus 10 years lag time, OR: 1.56 versus 2.22). Brachytherapy had no association with second cancer across all analyses.

CONCLUSIONS

Radiotherapy was associated with an increased risk of subsequent rectal cancer compared with patients unexposed to radiation. Colon may be free from the damage of radiation. Brachytherapy had no association with second rectal cancer or colon cancer.

New Insights in Prostate Cancer Development and Tumor Therapy: Modulation of Nuclear Receptors and the Specific Role of Liver X Receptors

Prostate cancer (PCa) incidence has been dramatically increasing these last years in westernized countries. Though localized PCa is usually treated by radical prostatectomy, androgen deprivation therapy is preferred in locally advanced disease in combination with chemotherapy. Unfortunately, PCa goes into a castration-resistant state in the vast majority of the cases, leading to questions about the molecular mechanisms involving the steroids and their respective nuclear receptors in this relapse. Interestingly, liver X receptors (LXRα/NR1H3 and LXRβ/NR1H2) have emerged as new actors in prostate physiology, beyond their historical roles of cholesterol sensors. More importantly LXRs have been proposed to be good pharmacological targets in PCa. This rational has been based on numerous experiments performed in PCa cell lines and genetic animal models pointing out that using selective liver X receptor modulators (SLiMs) could actually be a good complementary therapy in patients with a castration resistant PCa. Hence, this review is focused on the interaction among the androgen receptors (AR/NR3C4), estrogen receptors (ERα/NR3A1 and ERβ/NR3A2), and LXRs in prostate homeostasis and their putative pharmacological modulations in parallel to the patients' support.

Combined androgen blockade achieved better oncological outcome in androgen deprivation therapy for prostate cancer: Analysis of community-based multi-institutional database across Japan using propensity score matching

Background

This study investigated how differences in the method of the first‐line androgen deprivation therapy (ADT) affected the time to castration‐resistant prostate cancer.

Methods

The Japan Study Group of Prostate Cancer compiled a nationwide community‐based database on prostate cancer patients who underwent ADT. That database included 13 774 patients who were started on ADT by surgical or medical castration alone (monotherapy group, 5395 cases) or ADT in combination with a nonsteroidal anti‐androgen (combined androgen blockade (CAB) group, 8379 cases). We used logistic regression analysis with background factors as independent factors to calculate propensity scores in regard to selection of CAB. Next, for 8826 cases of propensity score‐matched patients, we compared the survival rates in the two groups.

Results

The CAB group showed a significantly better progression‐free survival (PFS) rate (65.6% vs 59.6% at 5 years; median time to progression, 11.6 vs 7.1 years; hazard ratio in the CAB group: 0.78, with a 95% confidence interval of 0.72 to 0.84; P < 0.001). In subgroup analysis based on the background factors, the PFS rate was generally better in the CAB group in all risk subgroups except for those having significant risk factors.

Conclusion

Propensity score matching analysis revealed the prolongation of PFS by CAB in prostate cancer patients without significant risk factors. It would possible to decide the type of the first‐line ADT according to the prostate cancer risk.