Incidental Meningioma With Altered PSMA Expression After Systemic Hormone Therapy and Local Radiotherapy Detected by 68 Ga-PSMA PET/CT.

ABSTRACT: A 59-year-old man underwent radical prostatectomy for adenocarcinoma in 2009. Because of the progression of PSA levels, a 68 Ga-PSMA PET/CT scan was performed in January 2020. A suspicious uptake was detected in the left cerebellar hemisphere, and there was no evidence of distant metastatic disease other than recurrent malignancy in the prostatectomy bed. MRI revealed a meningioma located in the left cerebellopontine angle. Although PSMA uptake of the lesion increased in the first imaging after hormone therapy, partial regression was noted after radiotherapy applied to this region.

Increased expression of androgen receptor and PSA genes in LNCaP (prostate cancer) cell line due to high concentrations of EGCG, an active ingredient in green tea.

OBJECTIVES: Androgen receptor (AR) play a key role in the onset and progression of prostate cancer. Epigallocatechin-3-gallate (EGCG) is a polyphenolic compound and the active ingredient in green tea, which is involved in modulating gene expression through epigenetic alterations. Previous studies have shown that EGCG at low concentrations reduces the expression of AR and prostate-specific antigen (PSA) in the LNCaP cell line of prostate cancer. In this study, the effect of higher EGCG concentrations on AR and PSA expression in LNCaP prostate cancer cell line was investigated. METHODS: In this study, LNCaP prostate cancer cell line was used and after MTT test, concentrations of 40, 60 and 80 µg/mL EGCG were used for treatment. Then, the expression of AR and PSA genes was evaluated by RT-PCR. AR protein expression was also assessed by Western blotting. RESULTS: The present study showed that treatment of LNCaPs cells by EGCG reduces cell proliferation. The IC50 value was 42.7 µg/mL under experimental conditions. It was also observed that EGCG at concentrations of 40 and 80 µg/mL increased the expression of AR and PSA (p<0.05). CONCLUSIONS: The present study showed that the effect of EGCG on AR expression was different at different concentrations, so that unlike previous studies, higher concentrations of EGCG (80 and 40 µg/mL) increased AR and PSA expression. It seems that due to the toxic effects of EGCG in high concentrations on cancer cells and the possibility of its effect on normal cells, more caution should be exercised in its use.

Early Prostate-Specific Antigen Kinetics for Low- and Intermediate-Risk Prostate Cancer Treated With Definitive Radiation Therapy.

PURPOSE: This study used a patient-specific model to characterize and compare ideal prostate-specific antigen (PSA) kinetics for low- and intermediate-risk prostate cancer after definitive radiation treatment with conventionally fractionated, hypofractionated, stereotactic body radiation therapy, or brachytherapy, both high-dose and low-dose rate. METHODS AND MATERIALS: This retrospective analysis includes low- and intermediate-risk patients with prostate cancer treated between 1998 and 2018 at an National Cancer Institute-designated comprehensive cancer center. Demographics and treatment characteristics were prospectively collected. Patients had at least 2 PSA measurements within 24 months of treatment and were free from biochemical recurrence. The incidence of, time to, and risk factors for PSA nadir (nPSA) and bounce (bPSA) were analyzed at 24 months after radiation therapy. Ideal PSA kinetics were characterized for each modality and compared. RESULTS: Of 1042 patients, 45% had low-risk cancer, 37% favorable intermediate risk, and 19% unfavorable intermediate risk. nPSAs were higher for ablative modalities, both as absolute nPSA and relative to initial PSA. Median time to nPSA ranged from 14.8 to 17.1 months. Over 50% treated with nonablative therapy (conventionally fractionated, hypofractionated, and low-dose rate) reached an nPSA threshold of ≤0.5 ng/mL compared with 23% of stereotactic body radiation therapy and 33% of high-dose rate cohorts. The incidence of bPSA was 13.3% and not affected by treatment modality, Gleason score, or prostate volume. PSA decay rate was faster for ablative therapies in the 6- to 24-month period. CONCLUSIONS: Analysis of PSA within 24 months after radiation therapy revealed ablative therapies are associated with a latent PSA response and higher nPSA. Multivariable logistics modeling revealed younger age, initial PSA above the median, presence of bPSA, and ablative therapy as predictors for not achieving nPSA ≤0.5 ng/mL. PSA decay rate appears to be faster in ablative therapies after a latent period. Understanding the different PSA kinetic profiles is necessary to assess treatment response and survey for disease recurrence.

Antihormone treatment differentially regulates PSA secretion, PSMA expression and 68Ga-PSMA uptake in LNCaP cells.

BACKGROUND: In recent years, a variety of innovative therapeutics for castration-resistant prostate cancer have been developed, including novel anti-androgenic drugs, such as abiraterone or VPC-13566. Therapeutic monitoring of these pharmaceuticals is performed either by measuring PSA levels in serum or by imaging. PET using PSMA ligands labeled with Fluor-18 or Gallium-68 is the most sensitive and specific imaging modality for detection of metastases in advanced prostate cancer. To date, it remains unclear how PSMA expression is modulated by anti-hormonal treatment and how it correlates with PSA secretion. METHODS: We analyzed modulation of PSMA-mRNA and protein expression, 68Ga-PSMA uptake and regulation of PSA secretion by abiraterone or VPC-13566 in LNCaP cells in vitro. RESULTS: We found that abiraterone and VPC-13566 upregulate PSMA protein and mRNA expression but block PSA secretion in LNCaP cells. Both anti-androgens also enhanced 68Ga-PSMA uptake normalized by the number of cells, whereas abiraterone and VPC-13566 reduced 68Ga-PSMA uptake in total LNCaP monolayers treated due to cell death. CONCLUSION: Our data indicate that PSA secretion and PSMA expression are differentially regulated upon anti-androgen treatment. This finding might be important for the interpretation of 68Ga-PSMA PET images in monitoring therapies with abiraterone and VPC-13566 in prostate cancer patients, but needs to be validated in vivo.

Psoralea corylifolia L. extract ameliorates benign prostatic hyperplasia by regulating prostate cell proliferation and apoptosis.

ETHNOPHARMACOLOGICAL RELEVANCE: Psoralea corylifolia L. seed (PCL), commonly known as "Poguzhi" or "BuguZhi", has been widely used to treat kidney yang deficiency in traditional Chinese medicine (TCM) where tonifying the yang deficiency is a representative understanding for treatment of hormonal deficiency disorders such as enuresis, oliguria, and prostatic diseases. Although PCL has been commonly used to treat problems of the urinary system, its efficacy against benign prostatic hyperplasia (BPH) has not yet been reported. AIM OF THE STUDY: In the present study, we aimed to assess the in vitro and in vivo efficacy of PCL against BPH, a condition which negatively impacts quality of life in men. MATERIALS AND METHODS: Normal human prostate cell lines, RWPE-1 and WPMY-1 cells, were stimulated with 10 nM dihydrotestosterone (DHT) to establish an in vitro BPH model. Subsequently, cells were treated with 100 or 200 µg/ml PCL, which inhibited cell proliferation without cytotoxicity, to evaluate the anti-BPH effect of PCL. Eight-week-old male Wistar rats were castrated, except for those in the control group (Con), and BPH was induced by subcutaneous injection of 10 mg/kg testosterone propionate (TP). Concurrent with daily TP injections, 5 mg/kg of finasteride (Fina) and 50 or 100 mg/kg PCL were orally administrated daily for four weeks, excluding the weekends. RESULTS: In DHT-stimulated RWPE-1 and WPMY-1 cells, expression of androgen receptor (AR) androgen signaling-related markers such as 5α-reductase 2 (5AR2), AR, and prostate-specific antigen (PSA) was upregulated, whereas 100 or 200 µg/ml of PCL treatment downregulated these markers. Furthermore, PCL significantly reduced the mRNA expression of anti-apoptotic genes and increased the mRNA expression of pro-apoptotic gene. In vivo, administration of PCL reduced prostate size and weight in TP-induced BPH rats. Moreover, histological alterations in epithelium thickness were significantly restored by the administration of PCL. Immunohistochemical analysis revealed increased expression of AR and proliferating cell nuclear antigen (PCNA) in TP-induced BPH prostates; these changes were suppressed by administration of 50 or 100 mg/kg PCL. CONCLUSIONS: We demonstrated the effect of PCL against BPH, mediated by the regulation of prostate cell proliferation and apoptosis, in DHT-stimulated normal human prostate cell lines and TP-induced BPH rats. These findings suggest that PCL could be a potential therapeutic agent against BPH.

Radiotherapy of Prostate Carcinoma: A Comparison of the Predictive Role of EAU Versus NCCN Risk Stratification Systems.

BACKGROUND/AIM: To compare the predictive efficacy of National Comprehensive Cancer Network (NCCN) and European Association of Urology (EAU) risk stratification systems in radiotherapy of prostate cancer. PATIENTS AND METHODS: One-thousand-nine-hundred-nine patients treated with definitive (1,074), adjuvant (381), and salvage radiotherapy (454) were analysed. RESULTS: Both systems significantly predicted biochemical-relapse-free-survival, metastasis-free-survival, and disease-free-survival, while only the NCCN system correlated with local-control in the definitive radiotherapy group. In the adjuvant setting, both systems failed to predict all outcomes. In the salvage setting, only the NCCN system significantly predicted biochemical-relapse-free-survival, metastasis-free-survival and disease-free-survival. CONCLUSION: This analysis confirms the efficacy of both systems in definitive radiotherapy and suggests the utility of the NCCN also in salvage radiotherapy.

Dithiocarbamate prodrugs activated by prostate specific antigen to target prostate cancer.

Disulfiram in conjunction with copper has been shown to be a potent anticancer agent. However, disulfiram's therapeutic potential in prostate cancer is hindered by off-target effects due to its reactive and nucleophilic thiol-containing component, diethyldithiocarbamate (DTC). To minimize undesirable reactivity, we have strategically blocked the thiol moiety in DTC with a cleavable p-aminobenzyl (pAB) group linked to peptide substrates recognized by prostate specific antigen (PSA). Here we report the synthesis and evaluation in cancer cell models of two PSA-activatable prodrugs: HPD (Ac-HSSKLQL-pAB-DTC and RPD (RSSYYSL-pAB-DTC). In vitro exposure to PSA was found to trigger activation of HPD and RPD to release diethyldithiocarbamate, and both prodrugs were found to induce toxicity in prostate cancer cells, with HPD showing the most promising selectivity. With copper supplementation, the IC50 of HPD was 1.4 µM in PSA-expressing LNCaP cells, and 11 µM in PC3 cells that do not express PSA. These studies demonstrate the utility of using peptide recognition handles to direct the activity of dithiocarbamate prodrugs for selective cytotoxicity of cancer cells.

Immunohistochemical analysis of the impact of ischemic change in benign prostatic hyperplasia.

OBJECTIVE: We conducted experiments to elucidate the impact of ischemic change on benign prostatic hyperplasia (BPH) using immunohistochemistry. METHODS: Medical records of consecutive patients over 60 years of age who underwent transurethral resection of the prostate for BPH between January 2009 and September 2012 were evaluated. As vascular risk factors, the presence or absence of diabetes mellitus, hypertension, current smoking, obesity, dyslipidemia, and diseases related to bladder function were investigated. As BPH-related factors, International Prostate Symptom Score, quality of life, maximal flow rate, postvoid residual volume, prostate-specific antigen, prostate volume, prostate calculi, and medication state for BPH were investigated. Immunohistochemistry was performed for hypoxia-inducible factor (HIF-1α), sex hormone receptors, and smooth muscle actin. Additionally, microvessel density (MVD) and diffuse fibrosis (DF) were evaluated. RESULTS: A total of 101 patients were included and HIF-1α expression in stroma and glands were observed in 56 (55.4%) and 34 (33.7%) cases, respectively. There was no significant association between HIF-1α expression and vascular risk factors or BPH-related variables. However, there was a significant correlation between the HIF-1α expression in stroma and higher MVD. HIF-1α expression in the stroma was also significantly correlated with higher expressions of the androgen and progesterone receptors in the stroma. DF was frequently found in cases with higher HIF-1α expression in the stroma than in those with lower HIF-1α expression. CONCLUSION: In patients with response to ischemic changes of the prostate, HIF-1α expression could be confirmed, and the expression of the androgen receptor was significantly lower in these patients. Chronic ischemic damage in the prostate can progress to a condition that is refractory to pharmacologic therapy. Chronic ischemic damage, which can progress to refractory phase to pharmacologic therapy, is correlated with the hormonal status of prostate.

Pao Pereira Extract Attenuates Testosterone-Induced Benign Prostatic Hyperplasia in Rats by inhibiting 5α-Reductase.

Benign prostatic hyperplasia (BPH) is one of the most common diseases in the urinary system of elderly men. Pao extract is an herbal preparation of the bark of the Amazon rainforest tree Pao Pereira (Geissospermum vellosii), which was reported to inhibit prostate cancer cell proliferation. Herein we investigated the therapeutic potential of Pao extract against BPH development in a testosterone-induced BPH rat model. The administration of testosterone induced the prostate enlargement, compared with the sham operated group with vehicle treatment. The BPH/Pao group showed reduced prostate weight comparable with BPH/finasteride group. Notably, Pao treatment did not significantly reduce body weights and sperm number of rats, compared with the control group. Furthermore, Pao extract treatment reduced the proliferative index in prostate glands and testosterone-induced expression levels of AR, as well as androgen-associated proteins such as SRD5A1 and PSA. Moreover, Pao extract and its active component, flavopereirine, induced cytotoxicity on human prostate epithelial RWPE-1 cells in a dose- and time- dependent manner with G2/M arrest. Consistently, Pao extract and flavopereirine suppressed the expression levels of SRD5A1, AR and PSA, respectively. Together, these data demonstrated that Pao extract suppresses testosterone-induced BPH development through inhibiting AR activity and expression, and suggested that Pao extract may be a promising and relative safe agent for BPH.

Clinicopathological predictors of positive 68Ga-PSMA-11 PET/CT in PSA-only recurrence of localized prostate cancer following definitive therapy.

OBJECTIVE: To demonstrate the effect of clinicopathological factors on 68Ga-PSMA-11 PET/CT positivity at the time of biochemical recurrence (BCR) of localized prostate cancer (PCa) following definitive therapy. METHODS: We retrospectively reviewed our institutional database for PCa patients who had BCR and subsequently underwent 68Ga-PSMA-11 PET/CT between April 2014 and February 2018. A total of 51 patients who were metastasis-free before PSMA imaging and previously treated with definitive therapy (radical prostatectomy or external beam radiotherapy) for localized disease (pT1c-T3b pN0-1 cM0) were included. RESULTS: 37 out of 51 patients (72.5%) had positive 68Ga-PSMA-11 PET/CT scans. Age at diagnosis, Gleason score (GS), D'Amico risk status of PCa, initial PSA level before treatment and PSA doubling time were not associated with PSMA positivity. Pre-scan PSA levels of > 0.2 ng/ml and PSA velocity of ≥ 1 ng/ml/year were significantly associated with increased PSMA positivity, whereas history of androgen deprivation therapy showed a trend towards significance. The optimal cutoffs for distinguishing between positive and negative scans were ≥ 0.71 ng/ml for pre-scan PSA and ≥ 1.22 ng/ml/yr for PSA velocity. In multivariable analysis, log pre-scan PSA and pre-scan PSA level > 0.2 ng/ml remained significant predictors for PSMA positivity, whereas the association of PSA velocity and of ADT was lost. CONCLUSIONS: In BCR of localized PCa following definitive therapy, pre-scan PSA was strongly associated with positive 68Ga-PSMA-11 scan, even at PSA levels ranging from 0.2 to 1.0 ng/ml. Therefore, clinical and pathological predictors of positive 68Ga-PSMA-11 PET/CT in PSA-only recurrence of localized prostate cancer need to be further elucidated.

Effects of Lespedeza Cuneata aqueous extract on testosterone-induced prostatic hyperplasia.

CONTEXT: Lespedeza cuneata G. Don (Fabaceae), has been used as a traditional treatment of various diseases. There is a report L. cuneata effects on hormone replacement therapy for endocrine-related disease. However, studies related to benign prostatic hyperplasia (BPH) have not been investigated. OBJECTIVE: The effects of L. cuneata aqueous extract (LCW) on testosterone-induced prostatic hyperplasia (TPH) were examined. MATERIALS AND METHODS: Male Wistar rats (10 weeks, 330-350 g) were randomly divided to 6 groups (n = 6): Control group; TPH group (3 mg/kg, s.c, daily); TPH + LCW (25, 50, 100 mg/kg); TPH + Finasteride 10 mg/kg for 6 weeks. At the end of treatment, histological change of prostate, serum dihydrotestosterone (DHT) level, mRNA expression of 5α-reductase, inflammatory factors, proliferating cell nuclear antigen (PCNA) and fibroblast growth factor-2 (FGF-2) in prostate were examined. Then, LCW was treated with BPH-1, a human BPH cell line, at 25, 50, 100 µg/mL for 24 h and examine mRNA level of androgen receptor (AR) and prostate-specific antigen (PSA). In addition, the content of vicenin-2 was analyzed. RESULTS: LCW treatment of TPH inhibited serum DHT levels by 54.5, 51.2 and 54.1% and mRNA expression of 5α-reductase were inhibited 54.3, 61.3 and 73.6%, respectively. In addition, mRNA expression of inflammatory factors, PCNA and FGF-2 were decreased in the prostate of rats. Also, LCW attenuated mRNA level of AR and PSA in BPH-1 cell. The content of vicenin-2 in the LCW was analyzed to 0.89 mg/g. DISCUSSION AND CONCLUSIONS: Based on the results, LCW is a potential pharmacological candidate for the treatment of prostatic hyperplasia.

68Ga-PSMA-11 PET/CT in prostate cancer patients with biochemical recurrence after radical prostatectomy and PSA <0.5 ng/ml. Efficacy and impact on treatment strategy.

PURPOSE: The primary aim of this retrospective, single-centre analysis was to assess the performance of 68Ga-PSMA-11 PET/CT in prostate cancer (PCa) patients in early PSA failure after radical prostatectomy (RP). The secondary aim was to assess the potential impact of 68Ga-PSMA-11 PET/CT on treatment strategy. METHODS: 68Ga-PSMA-11 PET/CT is performed in our institution within an investigational new drug (IND) trial in PCa patients with biochemical recurrence (BCR). The records of all patients enrolled between March 2016 and July 2017 were evaluated. These records were retrospectively analysed according to the following inclusion criteria: (a) RP as primary therapy, (b) proven BCR, ©) PSA levels in the range 0.2-0.5 ng/ml at the time of the 68Ga-PSMA-11 PET/CT investigation, and (d) no salvage radiotherapy (S-RT) performed after recurrence. The performance of 68Ga-PSMA-11 PET/CT was evaluated in terms of detection rate on a per-patient and a per-region basis (local vs. distant lesions). We further performed an intention-to-treat (ITT) analysis. The patient cohort was grouped into three subpopulations, blinded to the 68Ga-PSMA-11 PET/CT results, according to the patients' characteristics and different patterns of treatment: (1) S-RT (with or without systemic treatment), (2) stereotactic body radiotherapy (SBRT) (with or without systemic treatment), and (3) systemic treatment. The treatment strategy was re-evaluated for each patient taking into consideration the 68Ga-PSMA-11 PET/CT images. RESULTS: We enrolled 119 PCa patients (mean age 66 years, range 44-78 years) with a mean PSA level at the time of 68Ga-PSMA-11 PET/CT of 0.34 ng/ml (median 0.32 ng/ml, SD ±0.09, range 0.20-0.50 ng/ml). 68Ga-PSMA-1 1 PET/CT was positive in 41 of the 119 patients, resulting in an overall detection rate of 34.4%. 68Ga-PSMA-11 uptake was observed in the prostate bed (3 patients, 2.5%), in the pelvic lymph nodes (21, 17.6%), in the retroperitoneal lymph nodes (4, 3.4%) and in the skeleton (21, 17.6%). Regarding ITT, 81 patients (68.1%) were considered possible candidates for S-RT only in the prostate bed and none of the patients (0%) for SBRT. According to the 68Ga-PSMA-11 PET/CT results, the intended treatment was changed in 36 patients (30.2%). According to the PET/CT results, S-RT was recommended in 70 patients (58.8%), only to the prostate bed in 58 (48.7%) and SBRT in 29 (24.4%). The intended RT planning was modified in 36 (87.8%) of 41 patients with a positive 68Ga-PSMA-11 PET/CT result. CONCLUSION: In our patient series with PSA levels <0.5 ng/ml, 68Ga-PSMA-11 PET/CT had a detection rate of 34.4%. In the ITT analysis, 30.2% of patients had a change in the intended treatment. These data support the hypothesis that 68Ga-PSMA-11 PET/CT is a useful procedure in the management of PCa patients showing early recurrence after RP, and should be implemented in routine clinical practice.

68Ga-PSMA-11 PET/CT in recurrent prostate cancer: efficacy in different clinical stages of PSA failure after radical therapy.

OBJECTIVES: The primary objective was the evaluation of Gallium 68 (68Ga)-prostate-specific membrane antigen (PSMA)-11 positron emission tomography/computed tomography (PET/CT) detection rate, for identifying the site of prostate cancer (PCa) relapse (local vs systemic), stratifying the population according to different clinical stages of biochemical recurrence (BCR). Secondary aims were: 1) to evaluate the association of clinical/pathologic features and 68Ga-PSMA-11 PET/CT detection rate, 2) to compare 68Ga-PSMA-11 PET/CT with other imaging procedures, and 3) to evaluate the positive predictive value (PPV) in a per-patient analysis. MATERIAL AND METHODS: This population was enrolled through a prospective, open label, single-center trial performed at the Nuclear Medicine of the University Hospital of Bologna (Eudract: 2015-004589-27 OsSC). The inclusion criteria were: (1) proven PCa, (2) surgery or radiotherapy as definitive therapy, (3) proven BCR, (4) prostate-specific antigen (PSA) 0.2-2 ng/ml, (5) age ≥ 35 years, and 6() willing to sign an informed consent. Three-hundred and thirty-two (332) patients were enrolled between March 2016 and June 2017; mean/median PSA was 0.84/0.61 ng/ml, 97.9% (325/332) of patients received radical prostatectomy and 2.1% (7/332) radiotherapy. Different patterns of BCR were identified by referent physicians as follows: (a) persisting detectable PSA after radical prostatectomy in 13.5% (45/332) of patients (subgroup 1), (b) first-time PSA failure after radical therapy in 44.9% (149/332) (subgroup 2), and (c) PSA increase after salvage or hormonal therapy in 41.6% (138/332) (subgroup 3). RESULTS: Primary objective: 68Ga-PSMA-11 PET/CT detection rate was 53.6% (CI 95% 48.1%-59.1%). In a patient-based analysis, disease confined to pelvis (prostate bed and/or lymph-nodes) was detected in 24.7% of cases (82/332). The presence of at least one distant lesion was observed in 28.9% of cases (96/332). The detection rate in different subgroups was: subgroup 1 = 64.5%, subgroup 2 = 45.6%, and subgroup-3 = 58.7%. Secondary objectives: 1) PSA (p = 0.041) and PSAdt (p = 0.001) showed association with 68Ga-PSMA-11 PET/CT detection rate, and 2) correlative imaging was available in 73.2% of patients (243/332). When 68Ga-PSMA-11 PET/CT was positive, correlative imaging resulted negative in 83% of cases (108/130). 3) The calculated PPV was 96.2%. CONCLUSION: Our data confirmed the efficacy of 68Ga-PSMA-11 PET/CT for detecting local vs systemic disease in PCa patients presenting PSA failure after radical therapy. Furthermore, 68Ga-PSMA-11 PET/CT detection rate is different depending on the clinical stage of BCR, and this information should be taken into consideration by referring physicians.

Phase II Trial of Acai Juice Product in Biochemically Recurrent Prostate Cancer.

BACKGROUND: Plant derivatives have been studied as therapies for prostate cancer based on their purported anti-inflammatory and antioxidant properties and low toxicities. The acai berry is an example of a plant rich in phytochemicals, which may slow the growth of prostate cancer. METHODS: This was a phase II, Simon 2-stage clinical trial in patients with biochemically recurrent prostate cancer with a primary endpoint of prostate-specific antigen (PSA) response. Patients were asymptomatic, with a rising PSA of at least 0.2 ng/mL, and were treated with twice daily intake of Acai Juice Product until PSA progression, with a primary endpoint of PSA response. RESULTS: Twenty-one patients were enrolled in the first stage of the trial. One of those patients had a PSA response within the study time period. The PSA doubling time was lengthened in 71% of patients (95% confidence interval = 48% to 89%) on the trial, and in a small number of responders, this was sustained over an extended time. CONCLUSIONS: This study did not meet its primary endpoint of 50% PSA response. Nevertheless, the overall tolerability and effects on PSA stabilization warrant further exploration in a biochemically recurrent population.

Bone Flare to Androgen Deprivation Therapy in Metastatic, Hormone-Sensitive Prostate Cancer on 68Ga-Prostate-Specific Membrane Antigen PET/CT.

A 69-year-old man with newly diagnosed prostate cancer PSA 274 ng/mL, Gleason 4+3, T-stage 3b) underwent Ga-PSMA PET/CT for staging with follow-up scans 6 and 13 weeks after androgen deprivation therapy (ADT) initiation. Six weeks after ADT initiation, lymph node metastases observed at staging showed metabolic and radiological regression, whereas the skeleton showed increased PSMA uptake in existing bone metastases and several new PSMA-avid lesions. Skeletal PSMA uptake decreased after 13 weeks of ADT, and prostate-specific antigen decreased to 16 ng/mL. These findings suggest the presence of the flare phenomenon to ADT in bone metastases seen on PSMA PET/CT.

In vitro design of mesenchymal to epithelial transition of prostate cancer metastasis using 3D nanoclay bone-mimetic scaffolds.

Nanocomposite scaffolds show extensive applications in regenerative medicine and have shown promise as in vitro analogues of human tissue that can be used for the study of diseases. The complex nature of cancer metastasis is recently investigated using several 3D scaffold models. Herein, we report a polymer-nanoclay-based in vitro tumour model that recapitulates early stage of prostate cancer (PCa) colonization during skeletal metastasis on bone mimetic scaffolds. A unique cell culture system termed as "sequential culture (SC)" has been applied to create a bone-mimetic niche for colonization of PCa cells. Human mesenchymal stem cells (MSCs) were seeded on the bone-mimetic scaffolds, where they differentiated into bone cells and then formed mineralized bone matrix without osteogenic supplements. Further, PCa was seeded on MSCs-seeded scaffolds. Sequentially cultured PCa cells with MSCs formed self-organized multicellular tumoroids with distinct tight cellular junctions and hypoxic core regions. Extensive quantitative reverse transcription-polymerase chain reaction experiments were performed to evaluate the expressions of genes related to osteotropic bone metastasis of PCa. On the nanoclay scaffolds, the MSCs differentiated to mature osteoblasts and epithelial to mesenchymal transition was inhibited whereas mesenchymal to epithelial transition was enhanced, as also the hypoxia increased angiogenesis, and finally, PCa cells initiated osteoblastic lesion. Further, the SC technique has significant effects on expression of key metastasis-related genes. Therefore, the SC-based tumour model can be applied to recapitulate more consistent osteotropic cancer cell behavior in understanding tumour biology. This model also can be implemented for drug screening to target colonization stage of PCa cells in the bone microenvironment.

Heterogeneity in Definitions of High-risk Prostate Cancer and Varying Impact on Mortality Rates after Radical Prostatectomy.

BACKGROUND: Multiple definitions of high-risk prostate cancer (PC) exist in clinical practice. Prior studies have primarily evaluated the variability in prediction of biochemical recurrence. OBJECTIVE: To examine the impact of different definitions on mortality after radical prostatectomy (RP). DESIGN, SETTING, AND PARTICIPANTS: Retrospective study of 6477 men with clinically localized disease undergoing RP at Barnes-Jewish Hospital (St. Louis, MO, USA) and Cleveland Clinic (Cleveland, OH, USA) between 1995 and 2007. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Seven pretreatment definitions of high-risk PC (prostate-specific antigen [PSA] ≥20ng/ml, biopsy Gleason score 8-10, clinical stage ≥T2c, cT3, D'Amico definition, National Comprehensive Cancer Network definition, Kattan nomogram) were evaluated. The Kaplan-Meier method was used to generate unadjusted survival estimates. Multivariable Cox proportional hazard regression models (controlling for age) were used to estimate the hazard ratio (HR) for PC-specific mortality (PCSM) and overall mortality (OM) in the high-risk group compared to men with lower risk not meeting that definition. RESULTS AND LIMITATIONS: 6477 men were treated with RP from 1995 to 2007 and were followed for a median of 67 mo. Depending on the definition, patients with high-risk PC comprised between 0.7% (when using cT3 as the criterion) and 8.2% (when using the D'Amico criterion) of the population. The 10-yr PC survival estimates varied from 89.7% (PSA ≥20ng/ml) to 69.7% (cT3) and overall survival ranged from 83.4% to 58.1%. On multivariable analysis, all high-risk definitions were associated with a higher risk of PCSM compared to lower risk (HR ranging from 4.38 for PSA ≥20ng/ml to 19.97 for cT3; all p<0.001). All definitions of high risk except for preoperative PSA ≥20ng/ml were associated with a higher risk of OM (HR 1.72 for D'Amico to 3.31 for cT3; all p<0.01). CONCLUSIONS: Heterogeneity in outcomes existed, depending on the pretreatment definition of high-risk PC. Clinical stage T3 and Gleason score 8-10 were most strongly associated with PCSM and OM. PATIENT SUMMARY: There is variability in prostate cancer outcomes after surgery, depending on the definition of pretreatment high-risk disease used. Clinical stage T3 and high Gleason score were most strongly associated with prostate cancer-specific mortality and overall mortality.

Oncologic Outcomes of Definitive Treatments for Low- and Intermediate-Risk Prostate Cancer After a Period of Active Surveillance.

BACKGROUND: To compare oncologic outcomes of different definitive treatment (DT) modalities in a cohort of patients with prostate cancer (PCa) after active surveillance (AS). METHODS: We identified 237 patients with National Comprehensive Cancer Network (NCCN) low- and intermediate-risk prostate cancer diagnosed from 1990 to 2012 who did not undergo immediate DT within 12 months of diagnosis (ie, AS patients as well as watchful waiting and those refusing DT). Charts were examined for clinical/pathologic data and type of DT: surgery (RP), radiation including brachytherapy (XRT), cryotherapy, and androgen deprivation therapy monotherapy (ADT). The impact of DT on oncologic outcomes of biochemical recurrence (BCR), metastasis, disease-specific (DSS), and overall survival (OS) was examined with the Cox proportional hazards model, along with the Kaplan-Meier method and log-rank test. RESULTS: After median time on AS of 63.4 months, 40% of patients underwent DT: 47% XRT, 28% RP, 14% ADT, and 11% cryotherapy. On multivariable analysis, the use of XRT predicted higher BCR (hazard ratio [HR] 6.1, P = .001) and worse overall mortality (HR 2.1, P = .03) compared with other treatments, controlling for age, Charlson Comorbidity Index (CCI), stage, Gleason score, and NCCN risk category. Median follow-up was 71.7 months. On Kaplan-Meier analysis, 10-year OS was superior for RP versus XRT among patients with prostatic specific antigen (PSA) velocity >2.0 ng/mL/y. CONCLUSIONS: Low- and intermediate-risk patients with PCa who progress to DT after AS may be inadequately treated with radiation therapy compared with other DT modalities, especially when pretreatment PSA velocity is > 2 ng/mL/y.

Genomic Scores are Independent of Disease Volume in Men with Favorable Risk Prostate Cancer: Implications for Choosing Men for Active Surveillance.

PURPOSE: We sought to determine whether disease volume at prostate biopsy would correlate with genomic scores among men with favorable risk prostate cancer. MATERIALS AND METHODS: We identified all men with NCCN® (National Comprehensive Cancer Network®) very low and low risk disease who underwent Oncotype DX® prostate testing at our institution from 2013 to 2016. Disease volume was characterized as the percent of positive cores, the number of cores with greater than 50% involvement, the largest involvement of any single core and prostate specific antigen density. Nonparametric testing was performed to compare the median Genomic Prostate Score™ and the likelihood of favorable pathology findings between quartiles of disease volume. RESULTS: We identified 112 (37.8%) and 184 men (62.2%) at NCCN very low and low risk, respectively. Median scores did not differ significantly between disease volume quartiles (all p >0.05). However, the median likelihood of favorable pathology findings statistically differed between volume quartiles (all <0.05). Seven of the 105 men (6.3%) with very low risk disease were reclassified at low risk and 13 of 181 (7.2%) with low risk disease were reclassified at intermediate risk. Genomic disease reclassification did not depend on biopsy tumor volume. CONCLUSIONS: In patients with NCCN very low and low risk prostate cancer genomic scores did not demonstrate meaningfully significant differences by volume based on clinically established cutoff points. Moreover, genomic scores identified and reclassified men with higher risk disease despite generally acceptable surveillance characteristics in this group according to grade and volume. This suggests that in patients at low risk the tumor biological potential measured by genomics rather than by volume should inform decisions on active surveillance candidacy.

Effect on Overall Survival of Locoregional Treatment in a Cohort of De Novo Metastatic Prostate Cancer Patients: A Single Institution Retrospective Analysis From the Royal Marsden Hospital.

BACKGROUND: The optimal management of the primary tumor in metastatic at diagnosis (M1) prostate cancer (PCa) patients is not yet established. We retrospectively evaluated the effect of locoregional treatment (LRT) on overall survival (OS) hypothesizing that this could improve outcome through better local disease control and the induction of an antitumor immune response (abscopal effect). PATIENTS AND METHODS: M1 at diagnosis PCa patients referred to the Prostate Targeted Therapy Group at the Royal Marsden between June 2003 and December 2013 were identified. LRT was defined as either surgery, radiotherapy (RT) or transurethral prostatectomy (TURP) administered to the primary tumor at any time point from diagnosis to death. Kaplan-Meier analyses generated OS data. The association between LRT and OS was evaluated in univariate (UV) and multivariate (MV) Cox regression models. RESULTS: Overall 300 patients were identified; 192 patients (64%) experienced local symptoms at some point during their disease course; 72 patients received LRT (56.9% TURP, 52.7% RT). None of the patients were treated with prostatectomy. LRT was more frequently performed in patients with low volume disease (35.4% vs. 16.2%; P < .001), lower prostate-specific antigen (PSA) level at diagnosis (median PSA: 75 vs. 184 ng/mL; P = .005) and local symptoms (34.2% vs. 4.8%; P < .001). LRT was associated in UV and MV analysis with longer OS (62.1 vs. 55.8 months; hazard ratio [HR], 0.74; P = .044), which remained significant for RT (69.4 vs. 55.1 months; HR, 0.54; P = .002) but not for TURP. RT was associated with better OS independent of disease volume at diagnosis. CONCLUSION: These data support the conduct of randomized phase III trials to evaluate the benefit of local control in patients with M1 disease at diagnosis.