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

Physicochemical properties of inclusion complexes of highly soluble β-cyclodextrins with highly hydrophobic testosterone propionate

Hydroxypropyl-β-cyclodextrin (HP-β-CyD) and sulfobutyl ether-β-cyclodextrin (SBE-β-CyD) were used to generate hydrophilic complexes of the poorly water-soluble drug testosterone propionate (TP). The inclusion complexes were obtained by freeze-drying, and then analyzed at both liquid and solid states. Phase solubility studies, performed according to the type-A_L solubility diagrams of TP in presence of both CyDs, suggested the formation of water-soluble complexes at 1:1 molar ratio. These results were confirmed by continuous variation method (Job's plot). Both CyDs increased water-solubility of TP 100-fold as compared to the native drug. The host-guest arrangement of CyD complexes in a water solution was further investigated by one- and two-dimensional NMR spectroscopy, highlighting the insertion of the tetracyclic ring of TP into the CyD cavity, and the interaction of the pending ester chain of drug with the primary hydroxyl groups of CyDs at the narrow end of the toroid structure. In solid phase, FTIR-ATR spectroscopy showed that the CO stretching mode of the TP vibrational spectrum changed if the complex between the drug and CyDs occurred. This change is temperature-dependent, and its evolution, accounted for by deconvolution procedures, provided the thermodynamic parameters explaining the mechanisms involved in the formation of inclusion complexes.

Clinical performance of 68Ga-PSMA-11 PET/MRI for the detection of recurrent prostate cancer following radical prostatectomy

PURPOSE

Sensitive visualization of recurrent prostate cancer foci is a challenge in patients with early biochemical recurrence (EBR). The recently established ⁶⁸Ga-PSMA-11 PET/CT has significantly improved the detection rate with published values of up to 55% for patients with a serum PSA concentration between 0.2-0.5 ng/mL. The increased soft tissue contrast in the pelvis using simultaneous ⁶⁸Ga-PSMA-11 PET/MRI might further improve the detection rate in patients with EBR and low PSA values over PET/CT.

METHODS

We retrospectively analyzed a cohort of 56 consecutive patients who underwent a ⁶⁸Ga-PSMA-11 PET/MRI for biochemical recurrence in our institution between April and December 2016 with three readers. Median PSA level was 0.99 ng/mL (interquartile range: 3.1 ng/mL). Detection of PSMA-positive lesions within the prostate fossa, local and distant lymph nodes, bones, or visceral organs was recorded. Agreement among observers was evaluated with Fleiss's kappa (k).

RESULTS

Overall, in 44 of 56 patients (78.6%) PSMA-positive lesions were detected. In four of nine patients (44.4%) with a PSA < 0.2 ng/mL, suspicious lesions were detected (two pelvic and one paraaortic lymph nodes, and two bone metastases). In eight of 11 patients (72.7%) with a PSA between 0.2 and < 0.5 ng/mL, suspicious lesions were detected (two local recurrences, six lymph nodes, and one bone metastasis). Five out of 20 patients with a PSA < 0.5 ng/mL had extrapelvic disease. In 12 of 15 patients (80.0%) with a PSA between 0.5 and < 2.0 ng/mL, suspicious lesions were detected (four local recurrences, nine lymph nodes, and four bone metastases). In 20 of 21 patients (95.2%) with a PSA >2.0 ng/mL, suspicious lesions were detected. The overall interreader agreement for cancer detection was excellent (κ = 0.796, CI 0.645-0.947).

CONCLUSIONS

Our data show that ⁶⁸Ga-PSMA-11 PET/MRI has a high detection rate for recurrent prostate cancer even at very low PSA levels <0.5 ng/mL. Furthermore, even at those low levels extrapelvic disease can be localized in 25% of the cases and local recurrence alone is seen only in 10%.

[Cytoreductive, radical prostatectomy in metastatic prostate cancer]

The resection of the primary tumor in patients with metastatic prostate cancer is controversially debated. Retrospective clinical studies indicate survival benefits and prevention of secondary, locoregional complications; however, results of ongoing multicenter prospective studies are still lacking. This review highlights the rationale behind the cytoreductive prostatectomy and summarizes current clinical study results.

Predictors of overall survival in metastatic castration-resistant prostate cancer patients receiving [177Lu]Lu-PSMA-617 radioligand therapy

Prostate-specific membrane antigen (PSMA) is a promising target for the diagnosis of and therapy for metastatic castration-resistant prostate cancer (mCRPC). The aim of this study was to measure overall-survival (OS) in mCRPC patients who received either abiraterone or enzalutamide prior to PSMA therapy. The second aim of this study was to analyse the predictors of OS according to different pre-therapeutic parameters and also the responses to the first cycle of radioligand therapy (RLT) base on PSA level. Patients with mCRPC and a history of therapy with either abiraterone or enzalutamide or both, were included in this study. Different laboratory tests and pre-therapeutic parameters have been included into the analysis. One-hundred patients received a total of 347 cycles of Lu-PSMA (median: three cycles). 69 patients showed a decline in PSA two months after the first cycle, and 38 of those patients showed a PSA decline of = > 50%. The median OS was 60 weeks. In the multivariate analysis, the level of albumin, AST and haemoglobin, existence of liver metastases and a decline of > 14% in PSA level had a significant impact on overall-survival. The median OS is significantly longer in patients without hepatic involvement, with high levels of albumin and Hb and low levels of AST. A decline in PSA levels of more than 14% was the most important response parameter with regard to overall survival.

Positive surgical margins and biochemical recurrence following minimally-invasive radical prostatectomy - An analysis of outcomes from a UK tertiary referral centre

Background

Positive surgical margins are a strong prognostic marker of disease outcome following radical prostatectomy, though prior evidence is largely from a PSA-screened population. We therefore aim to evaluate the biochemical recurrence in men with positive surgical margins (PSM) after minimally-invasive radical prostatectomy (MIRP) in a UK tertiary centre.

Methods

Retrospective study of men undergoing laparoscopic or robotic-assisted radical prostatectomy between 2002 and 2014. Men with positive surgical margins (PSM) were identified and their biochemical recurrence (BCR) rate compared with men without PSM. The primary outcome measures were BCR rates and time to BCR. Cox regression was used to estimate adjusted hazard ratios for biochemical recurrence rate (BCR), accounting for potential confounders.

Results

Five hundred ninety-two men were included for analysis. Pre-operative D’Amico risk stratification showed 37.5%, 53.3% and 9.3% of patients in the low, intermediate and high-risk groups, respectively. On final pathological analysis, the proportion of patients with local staging pT2, pT3a and pT3b was 68.8%, 25.2% and 6.1% respectively. Overall positive margin rate was 30.6%. On multivariate analysis, the only pre-operative factor associated with PSM was age >65years. Patients with PSM were more likely to have higher tumour volume and more advanced pathological local stage. The BCR rate was 10.7% in margin-positive patients and 5.1% in margin-negative patients, at median 4.4-year follow-up. Upon multivariate analysis, high pre-operative PSA and high Gleason group were the only significant predictors of BCR (P<0.05).

Conclusions

In comparison to patients with negative surgical margins, those with PSM do not translate into worse medium-term oncological outcomes in the majority of cases amongst our cohort. We found that high pre-operative PSA and high Gleason group were the only significant predictors of BCR.

Electronic supplementary material

The online version of this article (10.1186/s12894-017-0262-y) contains supplementary material, which is available to authorized users.

Artesunate suppresses the viability and mobility of prostate cancer cells through UCA1, the sponge of miR-184

Artesunate (ART) is a sesquiterpene lactone isolated from the leafy portions of the Chinese herb Artemisia annua. Here, we evaluated the effect of ART on the prostate cancer (PCa) cell lines DU145 and LNCaP and explored its potential mechanisms. ART inhibited the viability and mobility of DU145 and LNCaP cells. Mechanistically, we found that UCA1, one of the most important lncRNAs in malignancies of the urinary system, may be a potential mediator contributing to the tumor suppressor function of ART. First, the UCA1 level was reduced significantly after being exposed to ART. In addition, UCA1 was up-regulated in prostate cancer tissues compared to hyperplastic prostatic tissues, and a higher UCA1 level predicted poor prognosis in PCa patients. Furthermore, reintroduction of UCA1 into PCa cells reversed the effect of ART on apoptosis and metastatic ability. Then we determined that the miR-184/Bcl-2 axis might be the downstream signaling pathway of UCA1 upon ART treatment. UCA1 binds to miR-184 through its seed sequences and may function as a sponge for miR-184.

The Prognostic Factors of Biochemical Recurrence-Free Survival Following Radical Prostatectomy

Objective: To evaluate outcomes, biochemical recurrence-free survival (BCRFS) and to identify parameters influencing BCRFS of radical prostatectomy (RP) and bilateral pelvic lymph node dissection in a single-institution. Methods: A retrospective review of prostate cancer (PC) patients received RP was identified from the medical records. Data was collected from 2007 to 2016. 178 patients received RP were enrolled in a study. These patients were evaluated on efficacy of RP by using prostate-specific antigen (PSA) to analyze BCRFS and compared with Gleason score, pathologic staging, margin status and lymph node status with BCRFS. Results: The median follow up was 32.5 months (n = 178). Sixty-nine patients had extracapsular extension on pathologic results whereas 93 patients were classified as a high risk group. The median time for biochemical recurrence (BCR) was 22.3 months. The 3-year BCRFS in patients with a Gleason score 6, 3+4, 4+3, 8 and 9-10 were 85.8%, 84.6%, 78.7%, 53.3% and 35.8% . Multivariate analysis showed that extracapsular extension was independently associated with BCRFS. Conclusions: New group grading system indicates impact on BCRFS on univariate analysis but show negative impact on a multivariate Cox regression, only pathologic staging was independently associated with the cancer control outcome.

Tissue-Based MicroRNAs as Predictors of Biochemical Recurrence after Radical Prostatectomy: What Can We Learn from Past Studies?

With the increasing understanding of the molecular mechanism of the microRNAs (miRNAs) in prostate cancer (PCa), the predictive potential of miRNAs has received more attention by clinicians and laboratory scientists. Compared with the traditional prognostic tools based on clinicopathological variables, including the prostate-specific antigen, miRNAs may be helpful novel molecular biomarkers of biochemical recurrence for a more accurate risk stratification of PCa patients after radical prostatectomy and may contribute to personalized treatment. Tissue samples from prostatectomy specimens are easily available for miRNA isolation. Numerous studies from different countries have investigated the role of tissue-miRNAs as independent predictors of disease recurrence, either alone or in combination with other clinicopathological factors. For this purpose, a PubMed search was performed for articles published between 2008 and 2017. We compiled a profile of dysregulated miRNAs as potential predictors of biochemical recurrence and discussed their current clinical relevance. Because of differences in analytics, insufficient power and the heterogeneity of studies, and different statistical evaluation methods, limited consistency in results was obvious. Prospective multi-institutional studies with larger sample sizes, harmonized analytics, well-structured external validations, and reasonable study designs are necessary to assess the real prognostic information of miRNAs, in combination with conventional clinicopathological factors, as predictors of biochemical recurrence.

Salvage lymph node dissection after 68Ga-PSMA or 18F-FEC PET/CT for nodal recurrence in prostate cancer patients

The management of patients with biochemical recurrence (BCR) after definitive treatment for prostate cancer remains controversial. Our aim was to determine survival rates and complications of salvage lymph node dissection (sLND) in patients with recurrent prostate cancer after radical prostatectomy, while evaluating biochemical response (BR) with two different positron emission tomography/computed tomography (PET/CT) tracers used for preoperative imaging. sLND was performed in 104 patients diagnosed with isolated nodal recurrence on either ¹⁸F-fluoroethylcholine (¹⁸F-FEC) or ⁶⁸Ga-PSMA-HBED-CC (⁶⁸Ga-PSMA) PET/CT. Surgical complications, BR, clinical recurrence (CR), and cancer-specific survival (CSS) were evaluated. Logistic regression was used to determine predictors of complete BR (cBR) and CR after sLND and survival rates were assessed. Median follow-up was 39.5 months. Median patient age and prostate-specific antigen (PSA) at sLND were 64 years and 4.1 ng/mL. Median number of lymph nodes (LNs) removed was 13; median number of positive LNs was 3 per patient. Rate of Clavien-Dindo Grade III complications was low (4.8%). 29.8% of patients developed cBR (PSA < 0.2 ng/mL), and 56.7% partial BR (PSA postoperative < PSA preoperative) after sLND. Patients with LN metastases diagnosed on ⁶⁸Ga-PSMA PET/CT showed a higher rate of cBR compared to ¹⁸F-FEC PET/CT (45.7 vs. 21.7%, p = 0.040). PSA at sLND (p = 0.031) and choice of PET tracer (p = 0.048) were independent predictors of cBR. The 5-year BCR-free, CR-free and CSS rates were 6.2%, 26.0%, and 82.8%, respectively. While preoperative staging with ⁶⁸Ga-PSMA seems superior, only a limited number of patients developed cBR after surgery. Most patients experienced BCR and CR during follow-up.

Concurrent treatment with simvastatin and NF-κB inhibitor in human castration-resistant prostate cancer cells exerts synergistic anti-cancer effects via control of the NF-κB/LIN28/let-7 miRNA signaling pathway

We examined the anti-cancer effects and molecular mechanism of simvastatin in human castration-resistant prostate cancer (CRPC) cells, particularly focused on LIN28B and its target molecule, let-7 microRNA (miRNA) among the various target genes of NF-κB. A human CRPC cell line (PC3) was used in the current study. Gene expression patterns were evaluated using real time-PCR and western blot analysis. CCK-8 assay was used for assessing cell viability and proliferation, and a clonogenic assay was adopted to evaluate clonal proliferative capabilities. Induction of apoptotic cell death was analyzed via flow cytometry. Small interfering RNA (siRNA) and short-hairpin RNA (shRNA) were used for manipulating the expression of genes of interest. PC3 showed relatively higher expression levels of LIN28B and lower expression levels of let-7 miRNAs. Simvastatin treatment significantly inhibited cell viability and clonal proliferation in a dose-dependent manner. Importantly, the downregulated let-7 miRNA family was restored after simvastatin treatment. We further observed that human CRPC cells transfected with LIN28B-siRNA or shRNA also showed upregulated let-7 miRNAs. Finally, dual treatment with simvastatin and an NF-κB inhibitor (CAPE) synergistically induced apoptotic cell death, along with reduction of LIN28B expression, and restoration of let-7 miRNAs levels. Our data illustrate that simvastatin remarkably inhibits the growth of human CRPC cells by suppressing NF-κB and LIN28B and subsequently upregulating let-7 miRNAs. Moreover, concurrent treatment with simvastatin and an NF-κB inhibitor synergistically suppressed the growth of human CRPC cells, suggesting a novel therapeutic approach for human CRPC treatment.

Does T1- and diffusion-weighted magnetic resonance imaging give value-added than bone scintigraphy in the follow-up of vertebral metastasis of prostate cancer?

PURPOSE

To evaluate the effectiveness of limited Magnetic Resonance (MR) images including T1- and diffusion-weighted image (DWI) for monitoring vertebral metastasis in patients with prostate cancer.

MATERIALS AND METHODS

From July 2014 to November 2016, patients diagnosed with spinal metastasis from prostate cancer using 99mTc bone scintigraphy were enrolled. Regardless of the primary local therapy, the changes in spinal metastasis were followed up using bone scan and biparametric MR (T1+DWI). All tests were followed up for more than 3 months.

RESULTS

Among the 14 follow-ups of 10 patients, 6 and 10 (including all progressed cases on bone scan) follow-ups were determined to show progressive disease using bone scan and biparametric MR, respectively. Otherwise, we could have predicted neurologic sequela earlier using biparametric MR. Examination time for biparametric MR was 15 minutes, and it was 4 hours for bone scan, respectively.

CONCLUSIONS

Although bone scan has been considered the standard test for bony metastasis in men with prostate cancer, limited MR including T1 and DWI has an additional benefit in monitoring spinal metastasis in patients who are already diagnosed as having spinal metastasis. The limited MR is more sensitive in detecting progressive disease. In addition, it can reduce neurologic complications caused by spinal metastasis.

[Significance of PSMA imaging in prostate cancer]

BACKGROUND

Prostate cancer (PCa) is one of the most common malignancies of men in developed countries. To improve clinical diagnostics of PCa, ⁶⁸Ga-PSMA-11 was recently introduced as a new PET tracer. ⁶⁸Ga-PSMA-11 is able to specifically bind to the prostate-specific membrane antigen (PSMA), which is upregulated on the surface of prostate cancer cells in most patients.

OBJECTIVES

To analyse the current significance of ⁶⁸Ga-PSMA-11 PET imaging in prostate cancer in relation to staging of men with initial diagnosis, biochemical recurrence and metastatic disease.

MATERIALS AND METHODS

Retrospective analysis of current literature (PubMed search) regarding ⁶⁸Ga-PSMA-11 PET diagnostics in primary staging, in biochemical recurrence and in metastasized disease.

RESULTS

Compared to conventional imaging, ⁶⁸Ga-PSMA-11 PET/CT reaches a higher sensitivity with an excellent specificity in the clinical diagnosis of primary staging as well as staging for recurrence and advanced, metastasized disease. In biochemical recurrence, ⁶⁸Ga-PSMA-11 PET/CT shows significantly higher detection rates in comparison to choline PET/CT, especially in patients with low PSA values. In the clinical diagnosis of recurrent disease, therapy concepts were changed in more than a quarter of the patients due to the use of ⁶⁸Ga-PSMA-11 PET/CT. The significance of staging with ⁶⁸Ga-PSMA-11 PET/CT in advanced metastasized patients remains uncertain.

CONCLUSIONS

Due to the excellent results of ⁶⁸Ga-PSMA-11 PET imaging, even in patients with slightly elevated PSA levels, it will continue to play an important role in clinical diagnostics of prostate cancer and, thus, its clinical utilization will become more widely spread.

Activity of cabazitaxel in patients with metastatic castration-resistant prostate cancer after treatment with single or dual regimens of novel androgen receptor-targeting agents

The purpose of this study was to evaluate the efficacy of cabazitaxel for patients with metastatic castration-resistant prostate cancer (mCRPC) after sequential therapy with docetaxel (DTX) and single or dual regimens of novel androgen receptor-axis-targeted (ARAT) agents. We retrospectively reviewed 84 consecutive patients treated with cabazitaxel at Kobe University Hospital and related hospitals from September 2014 to September 2016. The association of each prognostic parameter with progression-free survival (PFS) was evaluated, including the sequence of therapy. Patients were divided according to their treatment after receiving cabazitaxel as follows: group 1 (after DTX and single regimen of novel ARAT agent) and group 2 (after DTX and dual novel ARAT agents). Median PFS for cabazitaxel treatment was 10.3 months (range 4.5-14.2 months). Prostate-specific antigen (PSA) response rates (≥30%) were 46.8 and 46.1% in group 1 and group 2, respectively [p = 0.96, hazard ratio (HR) 1.02, 95% confidence interval (CI) 0.57-1.80]. PSA response rates (≥50%) were 43.8 and 26.9% in patients of group 1 and group 2, respectively (p = 0.18, HR 1.54, 95% CI 0.78-3.04). Univariate analysis revealed that PFS for cabazitaxel treatment was significantly associated with baseline alkaline phosphatase, bone metastasis, and prior sequential therapy. Multivariate analysis revealed that bone metastasis and prior sequential therapy were independently associated with PFS. Prior sequential therapy with single regimen or dual regimens of novel ARAT agents was independently associated with PFS of patients with mCRPC treated with cabazitaxel. The effect of cabazitaxel after the administration of DTX and single novel ARAT agent was more sustained.

Consensus statement on definition, diagnosis, and management of high-risk prostate cancer patients on behalf of the Spanish Groups of Uro-Oncology Societies URONCOR, GUO, and SOGUG

PURPOSE

Prostate cancer (PCa) is the most prevalent malignancy in men and the second cause of mortality in industrialized countries.

METHODS

Based on Spanish Register of PCa, the incidence of high-risk PCa is 29%, approximately. In spite of the evidence-based beneficial effect of radiotherapy and androgen deprivation therapy in high-risk PCa, these patients (pts) are still a therapeutic challenge for all specialists involved, in part due to the absence of comparative studies to establish which of the present disposable treatments offer better results.

RESULTS

Nowadays, high-risk PCa definition is not well consensual through the published oncology guides. Clinical stage, tumour grade, and number of risk factors are relevant to be considered on PCa prognosis. However, these factors are susceptible to change depending on when surgical or radiation therapy is considered to be the treatment of choice. Other factors, such as reference pathologist, different diagnosis biopsy schedules, surgical or radiotherapy techniques, adjuvant treatments, biochemical failures, and follow-up, make it difficult to compare the results between different therapeutic options.

CONCLUSIONS

This article reviews important issues concerning high-risk PCa. URONCOR, GUO, and SOGUG on behalf of the Spanish Groups of Uro-Oncology Societies have reached a consensus addressing a practical recommendation on definition, diagnosis, and management of high-risk PCa.

Early abiraterone acetate treatment is beneficial in Japanese castration-resistant prostate cancer after failure of primary combined androgen blockade

Background

Development of novel agents targeting the androgen axis has led to improved overall survival in castration-resistant prostate cancer (CRPC). This study aimed to investigate the optimal timing of treatment with one such agent, abiraterone acetate (AA), in Japanese patients.

Materials and methods

Between July 2014 and February 2016, 106 CRPC patients were administered AA in Nagoya City University Hospital, Nagoya, Japan and in four affiliated hospitals following failure of primary combined androgen blockade (CAB). Of these, records of 69 patients treated before chemotherapy were retrospectively analyzed. Patients were divided into two AA treatment groups: (1) first- or second-line after diagnosis of CRPC, designated the Early Group, and (2) third-line onwards, designated the Deferred Group. Prostate-specific antigen (PSA) response rate, ≥ 50% PSA decline rate with treatment, progression-free survival (PFS), and overall survival (OS) were compared between the two groups. National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0 was used to classify adverse events.

Results

In 24 patients in the Early Group and 45 patients in the Deferred Group, no significant differences in baseline parameters were observed between groups. PSA response rate, ≥ 50% PSA decline rate and PFS (but not OS) were significantly better in the Early Group than in the Deferred Group. Serum aspartate aminotransferase/alanine aminotransferase elevations were the most common Grade 3 treatment-related toxicities, and were clinically manageable. In subgroup analyses of the Early Group, comparison of first-line AA with second-line AA after flutamide treatment showed no changes in PSA response rate, PFS, or OS.

Conclusion

This study suggests improved favorable outcomes of first- or second-line AA treatment in Japanese chemotherapy-naïve CRPC patients after failed CAB; statistical confirmation of such improvement was evident for PFS, but not OS. In addition, early AA treatment exhibited an acceptable safety profile.

Predicting Response and Recognizing Resistance: Improving Outcomes in Patients With Castration-resistant Prostate Cancer

Optimal sequencing strategies for approved agents in metastatic castration-resistant prostate cancer (mCRPC) are unclear. Retrospective clinical studies suggest cross-resistance between specific therapies. This review assesses treatment decisions for mCRPC. Increased use of chemohormonal therapy in castration-sensitive disease may affect subsequent treatment decisions in mCRPC. Initial abiraterone or enzalutamide treatment may result in cross-resistance for subsequent androgen receptor-targeted therapy. Clinical responses may be seen in both docetaxel- and cabazitaxel-treated patients progressing after treatment with abiraterone or enzalutamide. These observations are supported by proposed resistance mechanisms. In conclusion, small, retrospective studies suggest cross-resistance between specific therapies in mCRPC. Larger prospective studies are required.

Impact of Early Salvage Radiation Therapy in Patients with Persistently Elevated or Rising Prostate-specific Antigen After Radical Prostatectomy

BACKGROUND

Salvage radiation therapy (SRT) is a recommended treatment option for biochemical recurrence after radical prostatectomy (RP). However, its effectiveness may be limited to specific categories of patients.

OBJECTIVE

We aimed to identify the optimal candidates for early SRT after RP.

DESIGN, SETTING, AND PARTICIPANTS

The study included 925 node-negative patients treated with SRT after RP at seven institutions. Patients received SRT for either prostate-specific antigen (PSA) rising, or PSA persistence after RP that was defined as PSA level ≥0.1 ng/ml at 1 mo after surgery. All patients received local radiation to the prostate and seminal vesicle bed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcome measured was distant metastasis after SRT. Regression tree analysis was used to develop a risk-stratification tool. Multivariable Cox regression analysis and nonparametric curve fitting methods were used to explore the relationship between PSA level at SRT and the probability of metastasis-free survival at 8 yr.

RESULTS AND LIMITATIONS

At a median follow-up of 8.0 yr, 130 patients developed distant metastasis. At multivariable analysis, pre-SRT PSA level was significantly associated with distant metastasis (hazard ratio: 1.06, p<0.0001). However, when patients were stratified into five risk groups using regression tree analysis (area under the curve: 85%), early SRT administration provided better metastasis-free survival in three groups only: (1) low risk: undetectable PSA after RP, Gleason score ≤7, and tumour stage ≥pT3b, (2) intermediate risk: undetectable PSA after RP with Gleason score ≥8, (3) high risk: PSA persistence after RP with Gleason score ≤7.

CONCLUSIONS

We developed an accurate risk stratification tool to facilitate the individualised recommendation for early SRT based on prostate cancer characteristics. Early SRT proved to be beneficial only in selected groups of patients who are more likely to be affected by clinically significant but not yet systemic recurrence at the time of salvage treatment administration.

PATIENT SUMMARY

In patients affected by prostate cancer recurrence after radical prostatectomy, the early administration of salvage radiation therapy is beneficial only for selected subgroups of patients. In this study, these groups of patients were identified.

Estradiol for the mitigation of adverse effects of androgen deprivation therapy

Prostate cancer (PCa) is the second most commonly diagnosed cancer in men. Conventional endocrine treatment for PCa leads to global sex steroid deprivation. The ensuing severe hypogonadism is associated with well-documented adverse effects. Recently, it has become apparent that many of the biological actions attributed to androgens in men are in fact not direct, but mediated by estradiol. Available evidence supports a primary role for estradiol in vasomotor stability, skeletal maturation and maintenance, and prevention of fat accumulation. Hence there has been interest in revisiting estradiol as a treatment for PCa. Potential roles for estradiol could be in lieu of conventional androgen deprivation therapy or as low-dose add-back treatment while continuing androgen deprivation therapy. These strategies may limit some of the side effects associated with conventional androgen deprivation therapy. However, although available data are reassuring, the potential for cardiovascular risk and pro-carcinogenic effects on PCa via estrogen receptor signalling must be considered.

Osteoporosis in Frail Patients: A Consensus Paper of the Belgian Bone Club

In this consensus paper, the Belgian Bone Club aims to provide a state of the art on the epidemiology, diagnosis, and management of osteoporosis in frail individuals, including patients with anorexia nervosa, patients on dialysis, cancer patients, persons with sarcopenia, and the oldest old. All these conditions may indeed induce bone loss that is superimposed on physiological bone loss and often remains under-recognized and under-treated. This is of particular concern because of the major burden of osteoporotic fractures in terms of morbidity, mortality, and economic cost. Therefore, there is an urgent need to appreciate bone loss associated with these conditions, as this may improve diagnosis and management of bone loss and fracture risk in clinical practice.

Testosterone Responders to Continuous Androgen Deprivation Therapy Show Considerable Variations in Testosterone Levels on Followup: Implications for Clinical Practice

PURPOSE

We determined whether men on continuous androgen deprivation therapy who achieve testosterone less than 0.7 nmol/l demonstrate subsequent testosterone elevations during followup and whether such events predict worse oncologic outcomes.

MATERIALS AND METHODS

We evaluated a random, retrospective sample of 514 patients with prostate cancer treated with continuous androgen deprivation therapy in whom serum testosterone was less than 0.7 nmol/l at University Health Network between 2007 and 2016. Patients were followed from the date of the first testosterone measurement of less than 0.7 nmol/l to progression to castrate resistance, death or study period end. Study outcomes were the development of testosterone elevations greater than 0.7, greater than 1.1 and greater than 1.7 nmol/l, and progression to a castrate resistant state. Survival curves were constructed to determine the rate of testosterone elevations. Multivariate Cox regression analysis was done to assess whether elevations predicted progression to castrate resistance.

RESULTS

Median patient age was 74 years and median followup was 20.3 months. Within 5 years of followup 82%, 45% and 18% of patients had subsequent testosterone levels greater than 0.7, greater than 1.1 and greater than 1.7 nmol/l, respectively. In 96% to 100% of these patients levels less than 0.7 nmol/l were subsequently reestablished within 5 years. No patient baseline characteristic was associated with elevations and elevations were not a significant predictor of progression to a castrate resistant state.

CONCLUSIONS

Men on continuous androgen deprivation therapy in whom initial testosterone is less than 0.7 nmol/l frequently show subsequent elevations in serum testosterone. Such a development should not trigger an immediate response from physicians as these events are prognostically insignificant with regard to oncologic outcomes. Levels are eventually reestablished at less than 0.7 nmol/l.

Abiraterone plus Prednisone in Metastatic, Castration-Sensitive Prostate Cancer

BACKGROUND

Abiraterone acetate, a drug that blocks endogenous androgen synthesis, plus prednisone is indicated for metastatic castration-resistant prostate cancer. We evaluated the clinical benefit of abiraterone acetate plus prednisone with androgen-deprivation therapy in patients with newly diagnosed, metastatic, castration-sensitive prostate cancer.

METHODS

In this double-blind, placebo-controlled, phase 3 trial, we randomly assigned 1199 patients to receive either androgen-deprivation therapy plus abiraterone acetate (1000 mg daily, given once daily as four 250-mg tablets) plus prednisone (5 mg daily) (the abiraterone group) or androgen-deprivation therapy plus dual placebos (the placebo group). The two primary end points were overall survival and radiographic progression-free survival.

RESULTS

After a median follow-up of 30.4 months at a planned interim analysis (after 406 patients had died), the median overall survival was significantly longer in the abiraterone group than in the placebo group (not reached vs. 34.7 months) (hazard ratio for death, 0.62; 95% confidence interval [CI], 0.51 to 0.76; P<0.001). The median length of radiographic progression-free survival was 33.0 months in the abiraterone group and 14.8 months in the placebo group (hazard ratio for disease progression or death, 0.47; 95% CI, 0.39 to 0.55; P<0.001). Significantly better outcomes in all secondary end points were observed in the abiraterone group, including the time until pain progression, next subsequent therapy for prostate cancer, initiation of chemotherapy, and prostate-specific antigen progression (P<0.001 for all comparisons), along with next symptomatic skeletal events (P=0.009). These findings led to the unanimous recommendation by the independent data and safety monitoring committee that the trial be unblinded and crossover be allowed for patients in the placebo group to receive abiraterone. Rates of grade 3 hypertension and hypokalemia were higher in the abiraterone group.

CONCLUSIONS

The addition of abiraterone acetate and prednisone to androgen-deprivation therapy significantly increased overall survival and radiographic progression-free survival in men with newly diagnosed, metastatic, castration-sensitive prostate cancer. (Funded by Janssen Research and Development; LATITUDE ClinicalTrials.gov number, NCT01715285 .).

Istaroxime, a potential anticancer drug in prostate cancer, exerts beneficial functional effects in healthy and diseased human myocardium

The current gold standard for prostate cancer treatment is androgen deprivation therapy and antiandrogenic agents. However, adverse cardiovascular events including heart failure can limit therapeutic use. Istaroxime, which combines Na⁺-K⁺-ATPase (NKA) inhibition with sarco/endoplasmic reticulum Ca²⁺-ATPase 2a (SERCA2a) stimulation, has recently shown promising anti-neoplastic effects in prostate cancer (PC) models and may also improve cardiac function. Considering the promising anticancer effects of istaroxime, we aimed to assess its functional effects on human myocardium.

Prostate Tumor Overexpressed-1 (PTOV1) promotes docetaxel-resistance and survival of castration resistant prostate cancer cells

Metastatic prostate cancer is presently incurable. The oncogenic protein PTOV1, first described in prostate cancer, was reported as overexpressed and significantly correlated with poor survival in numerous tumors. Here, we investigated the role of PTOV1 in prostate cancer survival to docetaxel and self-renewal ability. Transduction of PTOV1 in docetaxel-sensitive Du145 and PC3 cells significantly increased cell survival after docetaxel exposure and induced docetaxel-resistance genes expression (ABCB1, CCNG2 and TUBB2B). In addition, PTOV1 induced prostatospheres formation and self-renewal genes expression (ALDH1A1, LIN28A, MYC and NANOG). In contrast, Du145 and PC3 cells knockdown for PTOV1 significantly accumulated in the G2/M phase, presented a concomitant increased subG1 peak, and cell death by apoptosis. These effects were enhanced in docetaxel-resistant cells. Analyses of tumor datasets show that PTOV1 expression significantly correlated with prostate tumor grade, drug resistance (CCNG2) and self-renewal (ALDH1A1, MYC) markers. These genes are concurrently overexpressed in most metastatic lesions. Metastases also show PTOV1 genomic amplification in significant co-occurrence with docetaxel-resistance and self-renewal genes. Our findings identify PTOV1 as a promoter of docetaxel-resistance and self-renewal characteristics for castration resistant prostate cancer. The concomitant increased expression of PTOV1, ALDH1A1 and CCNG2 in primary tumors, may predict metastasis and bad prognosis.

Successful Yttrium-90 Microsphere Radioembolization for Hepatic Metastases of Prostate Cancer

Prostate cancer is the most common solid tumor malignancy worldwide with an estimated 180,000 new cases of prostate cancer and 26,000 deaths in the USA in 2016. Although significant advances in the treatment of prostate cancer have recently been made, the treatment of metastatic disease remains a challenge. With visceral metastases marking more advanced tumor stages, liver involvement is associated with the worst prognosis. So far, no locoregional treatment regimens for the management of liver metastases of prostatic cancer exist. Herein, we report for the first time a successful treatment of hepatic metastases of prostatic cancer using radioembolization with selective intra-arterial administration of Yttrium-90 resin microspheres.

Radium-223 dichloride for the treatment of castration-resistant prostate cancer with symptomatic bone metastases

INTRODUCTION

Castration-resistant prostate cancer (CRPC) is associated with the development of bone metastases, increased mortality, and a reduction in the patient's quality of life (QOL). The management of metastatic CRPC (mCRPC) has rapidly evolved over the past decade, with a number of available therapeutic agents improving overall survival. Radium-223 dichloride (radium-223), the first targeted alpha therapy, improves survival accompanied by QOL benefits with a favorable safety profile. It is approved in over 40 countries for the treatment of patients with CRPC with symptomatic bone metastases and no known visceral metastatic disease. Areas covered: The current management of CRPC in men with bone metastases, and in particular the role of radium-223 in this setting, is reviewed and discussed. A search of bibliographic databases for peer-reviewed literature and major meetings was conducted. Expert commentary: In treating patients with mCRPC, the best sequencing and/or combination of radium-223 with other agents has yet to be fully elucidated. The role of radium-223 in treating patients with hormone-sensitive metastatic prostate cancer who are candidates for chemotherapy should also be investigated in well-designed trials. The ability to tailor radium-223 therapy to both the clinical and genetic profiles of CRPC patients would be a promising development.

Risk of Testosterone Flare in the Era of the Saturation Model: One More Historical Myth

CONTEXT

When luteinizing hormone-releasing hormone (LHRH) agonists were introduced in the 1980s, it was universally believed that the initial transient rise in serum testosterone (T), termed T flare, caused rapid prostate cancer (PCa) growth and led to disease progression, complications, and death. It became routine to offer antiandrogens (AAs) to prevent these risks. However, over the last decade, it has become recognized that androgens have a finite ability to stimulate PCa growth (the saturation model), providing a theoretical challenge to the risks of T flare.

OBJECTIVE

To review evidence for the risks associated with T flare from a modern perspective, specifically prostate-specific antigen (PSA) flare, disease progression, and spinal cord compression.

EVIDENCE ACQUISITION

An Ovid Medline database search was conducted to identify articles related to "testosterone flare", "disease flare", and "PSA flare" associated with LHRH agonists. The literature review included papers published from May 1, 1980 through May 1, 2016. Key search terms included, luteinizing hormone-releasing hormone, gonadotropin-releasing hormone, and antiandrogens.

EVIDENCE SYNTHESIS

Initial administration of LHRH agonists uniformly results in peak increases in serum T by 40-100% on days 2-3, returning to baseline by days 7-8, after which T declines to castrate levels by approximately 2-3 wk. Of six LHRH agonist studies reporting PSA during the period of T flare, five showed no significant rise in PSA despite the presence of advanced disease with mean baseline PSA as high as ≥500ng/ml. Evidence for disease flare was limited to one report of greater bone pain with LHRH agonists alone versus LHRH agonists with AAs. Three other RCTs reported no disease flare. Rates of spinal cord compression were no greater for LHRH agonists alone compared with castration or estrogen treatment. We identified no studies of men treated with LHRH agonists versus placebo/no treatment to assess the effects of LHRH agonists compared with the natural history of advanced PCa.

CONCLUSIONS

Although T flare has been considered risky for 30 yr, a modern review of the evidence collected primarily in the 1980s and 1990s fails to support this view. Specifically, T flare does not appear to be associated with significantly increased PSA, disease progression, or adverse events, even in men with widely metastatic disease. These results are consistent with the saturation model, first introduced in 2006. There seems little value in adding AA to LHRH agonists, except possibly for men with extensive vertebral metastases and serum T concentrations well below the saturation point of approximately 250ng/dl (8.7nmol/l).

PATIENT SUMMARY

A review of the literature reveals no evidence for increased risks associated with testosterone flare from the initiation of luteinizing hormone-releasing hormone (LHRH) agonists. This appears to be an unsupported belief from an earlier era when our understanding of testosterone's relationship to prostate cancer was less sophisticated. Except in rare instances, there appears to be no need to use an androgen blocker when beginning treatment with LHRH agonists.

Lactate dehydrogenase predicts combined progression-free survival after sequential therapy with abiraterone and enzalutamide for patients with castration-resistant prostate cancer

BACKGROUND

An array of clinical issues remains to be resolved for castration-resistant prostate cancer (CRPC), including the sequence of drug use and drug cross-resistance. At present, no clear guidelines are available for the optimal sequence of use of novel agents like androgen-receptor axis-targeted (ARAT) agents, particularly enzalutamide, and abiraterone.

METHODS

This study retrospectively analyzed a total of 69 patients with CRPC treated with sequential therapy using enzalutamide followed by abiraterone or vice versa. The primary outcome measure was the comparative combined progression-free survival (PFS) comprising symptomatic and/or radiographic PFS. Patients were also compared for total prostate-specific antigen (PSA)-PFS, overall survival (OS), and PSA response. The predictors of combined PFS and OS were analyzed with a backward-stepwise multivariate Cox model.

RESULTS

Of the 69 patients, 46 received enzalutamide first, followed by abiraterone (E-A group), and 23 received abiraterone, followed by enzalutamide (A-E group). The two groups were not significantly different with regard to basic data, except for hemoglobin values. In a comparison with the E-A group, the A-E group was shown to be associated with better combined PFS in Kaplan-Meier analysis (P = 0.043). Similar results were obtained for total PSA-PFS (P = 0.049), while OS did not differ between groups (P = 0.62). Multivariate analysis demonstrated that pretreatment lactate dehydrogenase (LDH) values and age were significant predictors of longer combined PFS (P < 0.05). Likewise, multivariate analysis demonstrated that pretreatment hemoglobin values and performance status were significant predictors of longer OS (P < 0.05).

CONCLUSIONS

The results of this study suggested the A-E sequence had longer combined PSA and total PSA-PFS compared to the E-A sequence in patients with CRPC. LDH values in sequential therapy may serve as a predictor of longer combined PFS.

[Neuroendocrine prostate cancer: Natural history, molecular features, therapeutic management and future directions]

Neuroendocrine prostate cancer is a rare malignancy with a an adverse prognostic. Histologically, It can be pure (small cells or large cells neuroendocrine carcinoma) or mixed with a adenocarcinoma component. Rarely diagnosed de novo, neuroendocrine prostate cancer is generally associated with advanced stage disease resistant to castration. As such, this histological subtype could represent an aggressive evolution of prostatic adenocarcinoma, through the epithelio-neuroendocrine transdifferentiation mechanism (phenomenon of lineage plasticity). Nonetheless, neuroendocrine prostate cancer is a heterogeneous malignancy with multiple histopathological variants showing distinct clinical features. The broad variety of molecular analyses could help to understand the ontogeny of this histological subtype and its signaling pathways. This may also allow identifying diagnostic and prognostic biomarkers as well as potential molecular targets. However, treatment options are currently limited and consist only in platinium-based chemotherapy for advanced stage disease.

A phase II randomized trial of Observation versus stereotactic ablative RadiatIon for OLigometastatic prostate CancEr (ORIOLE)

Background

We describe a randomized, non-blinded Phase II interventional study to assess the safety and efficacy of stereotactic ablative radiotherapy (SABR) for hormone-sensitive oligometastatic prostate adenocarcinoma, and to describe the biology of the oligometastatic state using immunologic, cellular, molecular, and functional imaging correlates. 54 men with oligometastatic prostate adenocarcinoma will be accrued. The primary clinical endpoint will be progression at 6 months from randomization with the hypothesis that SABR to all metastases will forestall progression by disrupting the metastatic process. Secondary clinical endpoints will include local control at 6 months post-SABR, toxicity and quality of life, and androgen deprivation therapy (ADT)-free survival (ADT-FS). Further fundamental analysis of the oligometastatic state with be achieved through correlation with investigational ¹⁸F–DCFPyL PET/CT imaging and measurement of circulating tumor cells, circulating tumor DNA, and circulating T-cell receptor repertoires, facilitating an unprecedented opportunity to characterize, in isolation, the effects of SABR on the dynamics of and immunologic response to oligometastatic disease.

Methods/design

Patients will be randomized 2:1 to SABR or observation with minimization to balance assignment by primary intervention, prior hormonal therapy, and PSA doubling time. Progression after 6 months will be compared using Fisher’s exact test. Hazard ratios and Kaplan-Meier estimates of progression free survival (PFS), ADT free survival (ADT-FS), time to locoregional progression (TTLP) and time to distant progression (TTDP) will be calculated based on an intention-to-treat. Local control will be assessed using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria. Withdrawal from the study prior to 6 months will be counted as progression. Adverse events will be summarized by type and grade. Quality of life pre- and post- SABR will be measured by Brief Pain Inventory.

Discussion

The ORIOLE trial is the first randomized, non-blinded Phase II interventional study in the North America evaluating the safety and efficacy of SABR in oligometastatic hormone-sensitive prostate cancer. Leading-edge laboratory and imaging correlates will provide unique insight into the effects of SABR on the oligometastatic state.

Trial registrations

ClinicalTrials.gov Identifier: NCT02680587.

URL of Registry: https://clinicaltrials.gov/show/NCT02680587

Date of Registration: 02/08/2016.

Date of First Participant Enrollment: 05/23/2016.

Triptorelin for the relief of lower urinary tract symptoms in men with advanced prostate cancer: results of a prospective, observational, grouped-analysis study

BACKGROUND

Lower urinary tract symptoms (LUTSs) may develop in men with prostate cancer (PCa) and can impact quality of life (QoL). Gonadotropin-releasing hormone (GnRH) agonists as androgen deprivation therapy are standard treatment for PCa, however, data are limited on their effects on LUTSs. A grouped analysis of national observational, non-interventional studies initiated in clinical practice was performed to assess the effectiveness of triptorelin in reducing moderate or severe LUTSs, measured using the International Prostate Symptom Score (IPSS) in men with advanced or metastatic PCa.

METHODS

Men with PCa and LUTSs scheduled to receive triptorelin (3-month or 1-month extended release formulation) were recruited into prospective, non-interventional studies at centres in Algeria, Australia, Belgium, China, Hungary, Romania and South Korea. The primary effectiveness endpoint was the proportion of patients with moderate or severe LUTSs, assessed by IPSS, after 48 weeks. Secondary endpoints included: total IPSS, QoL due to urinary symptoms (IPSS Question 8) and prostate-specific antigen (PSA) levels at 24 and 48 weeks.

RESULTS

A total of 2701 patients were recruited; 1851 patients with moderate or severe LUTSs at baseline (IPSS > 7), received triptorelin and had follow-up IPSS (efficacy population). The proportion of patients with moderate or severe LUTSs was reduced to 67.2% from baseline at week 48, following a reduction to 75.9% at week 24: the overall time effect was significant (p < 0.001). QoL due to urinary symptoms significantly improved from a mean score of 3.7 at baseline, to adjusted means of 2.5 and 2.1, at weeks 24 and 48, respectively (p < 0.001 versus baseline). Mean PSA levels were reduced from 158.8 ng/ml at baseline to 11.5 and 16.0 ng/ml at weeks 24 and 48, respectively.

CONCLUSIONS

Within the limitations of these observational studies, improvements in LUTSs and QoL observed after 24 weeks and maintained at 48 weeks indicate that triptorelin-induced effects improve LUTSs in patients with advanced PCa.

The value of multimodality imaging in the investigation of a PSA recurrence after radical prostatectomy in the Irish hospital setting

INTRODUCTION

The diagnostic evaluation of a PSA recurrence after RP in the Irish hospital setting involves multimodality imaging with MRI, CT, and bone scanning, despite the low diagnostic yield from imaging at low PSA levels. We aim to investigate the value of multimodality imaging in PC patients after RP with a PSA recurrence.

METHODS

Forty-eight patients with a PSA recurrence after RP who underwent multimodality imaging were evaluated. Demographic data, postoperative PSA levels, and imaging studies performed at those levels were evaluated.

RESULTS

Eight (21%) MRIs, 6 (33%) CTs, and 4 (9%) bone scans had PCa-specific findings. Three (12%) patients had a positive MRI with a PSA <1.0 ng/ml, while 5 (56%) were positive at PSA ≥1.1 ng/ml (p = 0.05). Zero patient had a positive CT TAP at a PSA level <1.0 ng/ml, while 5 (56%) were positive at levels ≥1.1 ng/ml (p = 0.03). Zero patient had a positive bone at PSA levels <1.0 ng/ml, while 4 (27%) were positive at levels ≥1.1 ng/ml (p = 0.01).

CONCLUSION

The diagnostic yield from multimodality imaging, and isotope bone scanning in particular, in PSA levels <1.0 ng/ml, is low. There is a statistically significant increase in the frequency of positive findings on CT and bone scanning at PSA levels ≥1.1 ng/ml. MRI alone is of investigative value at PSA <1.0 ng/ml. The indication for CT, MRI, or isotope bone scanning should be carefully correlated with the clinical question and how it will affect further management.

Modern treatment of metastatic prostate cancer

The treatment of prostate cancer with remote metastases has advanced greatly in recent years. Treatment options are dependent on the extent of the metastases, the patient’s general condition and wishes, and the treatment response. We present an overview of the latest options for systemic treatment of patients with metastatic prostate cancer, based on availability in Norway.

68Ga-PSMA-11 PET/CT: the rising star of nuclear medicine in prostate cancer imaging?

Ever since the introduction of ⁶⁸Ga-prostate-specific membrane antigen 11 positron-emission tomography/computed tomography (⁶⁸Ga-PSMA-11 PET/CT) a few years ago, it has rapidly achieved great success in the field of prostate cancer imaging. A large number of studies have been published to date, indicating a high potential of ⁶⁸Ga-PSMA-11 PET/CT in the work-up of prostate cancer patients, including primary diagnosis, staging and biochemical recurrence. The aim of this review is to present the most important data on this novel, highly promising imaging technique, and to formulate recommendations for possible applications of ⁶⁸Ga-PSMA-11 PET/CT in clinical routine.

Therapy assessment in prostate cancer using choline and PSMA PET/CT

While PET with non-FDG tracers (mainly choline and Ga-PSMA) has commonly been used for restaging in men with biochemically recurrent prostate cancer, as well as for primary staging, it is only recently that a few preliminary studies have addressed the possible use of PET for monitoring the response to systemic therapy of metastatic disease, especially innovative treatments such as abiraterone and enzalutamide. This article aims to evaluate the role of PET imaging with different non-FDG radiotracers for assessment of therapy in advanced prostate cancer patients.