Treatment outcomes and late toxicities of intensity-modulated radiation therapy for 1091 Japanese patients with localized prostate cancer

Aim

This study aimed to evaluate the treatment result of intensity-modulated radiation therapy (IMRT) in a large number of Japanese patients with prostate cancer.

Results of combined radiotherapy and hormonal treatment of prostate cancer patients with initial PSA value >40 ng/ml

AimTo evaluate the outcome of prostate cancer patients with initial PSA value >40 ng/ml.BackgroundThe outcome of prostate cancer patients with very high initial PSA value is not known and patients are frequently treated with palliative intent. We analyzed the outcome of radical combined hormonal treatment and radiotherapy in prostate cancer patients with initial PSA value >40 ng/ml.MethodsBetween January 2003 and December 2007 we treated, with curative intent, 56 patients with non-metastatic prostate cancer and initial PSA value >40 ng/ml. The treatment consisted of two months of neoadjuvant hormonal treatment (LHRH analog), radical radiotherapy (68–78 Gy, conformal technique) and an optional two-year adjuvant hormonal treatment.ResultsThe median time of follow up was 61 months. 5-Year overall survival was 90%. 5-Year biochemical disease free survival was 62%. T stage, Gleason score, PSA value, and radiotherapy dose did not significantly influence the outcome. Late genitourinal and gastrointestinal toxicity was acceptable.ConclusionRadical treatment in combination with hormonal treatment and radiotherapy can be recommended for this subgroup of prostate cancer patients with good performance status and life expectancy.     

Signification d’une hyperfixation prostatique du fluorodésoxyglucose (18F) chez un patient sans antécédent de cancer de la prostate. Cas cliniques,revue et méta-analyse de la littérature

FDG is not suited for the detection of prostate cancer. However, high prostate uptake demonstrated unexpectedly on FDG PET/CT requested for another indication may lead to the detection of prostate cancer, although a non-malignant origin is more common. We report 4 cases of prostate incidentaloma detected on high FDG prostate uptake, corresponding to 4 typical images and circumstances: diffuse uptake, focal uptake with various levels of SUV_max and of serum PSA level assayed on the basis of PET/CT result. We performed a meta-analysis of the 6 series in the literature currently reporting characterisation of prostate incidentalomas, in a total of 47,935 FDG PET, the average frequency of this incidentaloma is 1.5%; it was characterised in 68% of cases, corresponding to cancer in 16% of characterised cases, adenocarcinoma in 75 cases/78. There was no correlation between the Gleason score and the SUV_max; adenocarcinoma Gleason = 6 can be unexpectedly detected with FDG. Among the risk factors for malignancy, there is a SUV_max > 3, a peripheral location within the prostate and no calcification in the hypermetabolic area. Prostate biopsy may be indicated only in case the management of the patient would be modified if prostate cancer is confirmed; it is prompted in the case of clear elevation of serum PSA level, but also when serum PSA level is normal but there is one or several risk factors on FDG PET/CT images.     

The impact of PSA and digital rectal examination on the risk of prostate cancer specific mortality in men with a PSA level <2.5 ng/ml

IntroductionIt is unknown whether a normal range, diagnostic serum prostate specific antigen (PSA) level's influence on prostate cancer specific mortality (PCSM) is dependent upon digital rectal examination (DRE) findings.MethodsBetween 2004 and 2007, 9081 men diagnosed with non-palpable (T1c, N = 1710) or palpable (T2–T4, N = 7371) and non-metastatic prostate cancer (PC) were identified from surveillance, epidemiology, and end results data, selected based on pre-treatment PSA < 2.5 ng/ml. A multivariable competing risks regression model evaluated whether DRE findings interacted with PSA level in predicting risk of PCSM.ResultsAfter median follow-up of 2.83 years, 118 of 548 deaths (21.5%) were due to PC. Increasing diagnostic PSA was associated with increased risk of PCSM (AHR = 3.52; 95% CI: 1.25–9.89; P = .017) in men with T1c, Gleason score 7–10 PC, but decreased PCSM risk (AHR = 0.66; 95% CI: 0.52–0.83; P < .001) for men with T2–T4 PC and any Gleason score.DiscussionFor men with diagnostic PSA level <2.5 ng/ml and palpable PC, risk of early PCSM increases by 34% for a 1 point decrease in PSA from 2. This suggests the existence of clinically detectable, low PSA secreting disease with an elevated risk of early PCSM, highlighting the importance of the DRE in men with PC and normal range, diagnostic PSA.     

Prostate-specific antigen and 17-hydroxylase polymorphic genotypes in patients with prostate cancer and benign prostatic hyperplasia

We investigated the association of prostate cancer (PCa) and benign prostatic hyperplasia (BPH) with genetic polymorphisms in prostate-specific antigen (PSA) (-158 G/A) and 17-hydroxylase (CYP17) (-34 T/C) genes in a Turkish population. In this study, we investigated the distribution of these polymorphisms in 148 PCa patients, 136 BPH patients, and 102 healthy individuals as controls. The polymorphisms were analyzed using polymerase chain reaction-restriction fragment length polymorphism assay. Genotype and allele frequencies were calculated, and their associations with PCa or BPH risk are assayed. The frequency of PSA gene GA and GG genotypes was significantly higher in PCa patients than in controls (p = 0.017 and p = 0.019, respectively). GG genotype was also associated with BPH (p = 0.033). In a case analysis, according to Gleason score, the association of PSA gene GG genotype with Gleason score >7 was near to statistical significance (odds ratio, 2.94; 95% confidence interval, 0.95-9.28). There was also an association between CYP17 polymorphism and BPH (p = 0.004). No association was observed between PCa and CYP17 gene polymorphism. These data demonstrate that PSA gene promoter variation may play a significant role in the development of PCa and BPH, and that CYP17 gene polymorphism may be associated with BPH in the Turkish population studied.     

Synthesis and evaluation of a novel near-infrared fluorescent probe based on succinimidyl-Cys-C(O)-Glu that targets prostate-specific membrane antigen for optical imaging

Prostate-specific membrane antigen (PSMA), which is highly expressed in both localized and metastatic prostate cancer (PCa), is an ideal target for imaging and therapy of PCa. We previously reported radiolabeled asymmetric urea derivatives as a PSMA-targeting radiotracer for single-photon emission computed tomography (SPECT) and positron emission tomography (PET) imaging. Here, based on these radiopharmaceutical probes, we designed a novel near-infrared (NIR) fluorescent imaging probe (800CW-SCE) by chemical conjugation between IRDye 800CW-Maleimide and an asymmetric urea compound, known as PSMA inhibitor, for optical imaging. In the in vitro cellular uptake study, 800CW-SCE was internalized into PSMA-positive PCa cells (LNCaP cells) but not into PSMA-negative PCa cells (PC-3 cells). Moreover, in the in vivo imaging study, the probe was highly accumulated in LNCaP tumors but not in PC-3 tumors, and remained in LNCaP tumors until 24 h after intravenous administration. These results suggest that the potent NIR conjugate may contribute to clinical intraoperative optical imaging.     

The importance of an exponential prostate-specific antigen decline after external beam radiotherapy for intermediate risk prostate cancer

Background: To study the influence of an exponential prostate-specific antigen (PSA) decline on biochemical failure after external-beam radiotherapy (EBRT). Methods: We analyzed 114 patients with intermediate risk prostate cancer (Gleason ≤ 6 and PSA 10–20 or Gleason 7 and PSA <10). Patients were randomized between EBRT doses of either 70.2 Gy or 79.2 Gy (1.8 Gy per day). All patients had a follow up of at least six PSA measurements post-EBRT. Exponential decline and PSA half life were included in a Cox regression analysis for factors associated with biochemical failure. Results: A total of 80/114 (70.2%) patterns were classified as having an exponential PSA decline. Both exponential decline (HR 0.115, 95%CI 0.03–0.44, p = 0.0016) and PSA half life ratio were statistically significant predictors (HR 1.03 (95% CI 1.01–1.06)) of biochemical failure. In the model predicting for exponential decline, none of the factors were significant. Conclusion: Patients with an exponential PSA decline show a better biochemical outcome in the long term.     

Combined hypermethylation of APC and GSTP1 as a molecular marker for prostate cancer: quantitative pyrosequencing analysis

A total of 149 human prostate tissues obtained from our institute were assessed: 52 specimens of benign prostate hyperplasia (BPH) and 97 specimens of prostate cancer (PCa). The methylation status of the genes of Adenomatous polyposis coli (APC) and glutathione-S-transferase-P1 (GSTP1) was analyzed by quantitative pyrosequencing. A methylation score (M score) was calculated to capture the combined methylation level of both genes. The methylation level of each single gene and that of both genes combined was significantly higher in PCa specimens than in BPH (each p < 0.001). The value of APC methylation, GSTP1 methylation, and M score for predicting PCa was measured by the area under the receiver operating characteristic (ROC) curve and reached 0.954, 0.942, and 0.983, respectively. The sensitivity and specificity of the M score in discriminating between PCa and BPH reached 92.8% and 100.0%, respectively. The M score was positively associated with the serum prostate-specific antigen (PSA) level (p trend < 0.001). Our study demonstrates that the quantitative measurement of two methylation markers might drastically improve the ability to discriminate PCa from BPH.     

The clinical significance of circulating miR-21, miR-142, miR-143, and miR-146a in patients with prostate cancer

BackgroundProstate cancer (PCa) is the most common type of solid tissue cancer among men in western countries. In this study, we determined the levels of circulating miR-21, miR-142, miR-143, miR-146a, and RNU 44 levels as controls for early diagnosis of PCa.MethodsThe circulating miRNA levels in peripheral blood samples from 43 localized PCa patients, 12 metastatic PCa (MET) patients, and a control group of, 42 benign prostate hyperplasia (BPH) patients with a total of 97 volunteers were determined the by PCR method.ResultsNo differences in the DCT values were found among the groups. In PCa and PCaMet groups the expression of miR21 and miR142 were higher compared to the BHP group. No other differences were observed among the other groups. miR21 expression in the PCa group was 6.29 folds upregulated whereas in the PCaMet group 10.84 folds up-regulated. When the total expression of miR142 is evaluated, it showed a positive correlation with mir21 and mir 146 (both p<0.001). Also, the expression of miR146 shows a positive correlation with both miR21 and miR143 (both p<0.001). Expression of miRNAs was found to be an independent diagnostic factor in patients with Gleason score, PSA, and free PSA levels.ConclusionsOur study showed that co-expression of miR21, miR-142, miR-143, and miR-146a and the upregulation of miR-21 resulted in increased prostate carcinoma cell growth. In the PCaMet group, miR21 is the most upregulated of all miRNAs. These markers may provide a novel diagnostic tool to help diagnose PCa with aggressive behavior.     

前列腺PI-RADS V2.1评分联合血清PSA相关指标对灰区前列腺癌的诊断价值研究

摘要 目的：探讨前列腺影像报告和数据系统第2.1版（PI-RADS V2.1）评分联合血清前列腺特异抗原（PSA）相关指标对灰区前列腺癌的诊断价值。方法：回顾性分析2016年1月至2019年12月的187例经病理证实且PSA为灰区（4-10 ng/mL）的前列腺癌或前列腺增生患者资料。根据病理结果分为前列腺癌（PCa）组与前列腺增生组（BPH）组。由两名经验丰富的MRI诊断医师通过盲法对所有患者MRI图像进行PI-RADS V2.1评分,统计并计算血清PSA相关指标：总前列腺特异抗原（t-PSA）、游离前列腺特异抗原（f-PSA）、游离前列腺特异抗原与总前列腺特异抗原比值（f-PSA/t-PSA）、前列腺特异抗原密度（PSAD）。采用t检验比较各项指标在两组间的差异性,并使用受试者工作曲线（ROC）分析各项指标对灰区前列腺癌的诊断效能。结果：PI-RADS V2.1评分与PSAD在PCa与BPH组之间的差异具有统计学意义（P＜0.05）,而t-PSA、f-PSA、f-PSA/t-PSA在PCa与BPH组之间的差异均无统计学意义（P＞0.05）。根据ROC曲线分析,PI-RADS V2.1评分、PSAD、PI-RADS V2.1评分联合PSAD诊断灰区前列腺癌的曲线下面积（AUC）分别为0.814、0.671及0.838,且PI-RADS V2.1评分联合PSAD的AUC显著高于单独应用PI-RADS V2.1评分（Z=1.989,P＜0.05）与PSAD（Z=3.174,P＜0.05）。结论：PI-RADS V2.1评分与PSAD对诊断灰区前列腺癌具有较高诊断效能,且联合PI-RADS V2.1评分与PSAD能进一步提高诊断效能。     

Explication of the roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) as diagnostic and predictor tools for prostate cancer in equivocal PSA range of 4–10 ng/mL

BackgroundProstate cancer (PCa) is one of the most commonly encountered cancers and the leading cause of death worldwide. Currently used biomarkers accounts difficulties in discriminating benign from malignant cases or predicting outcome, so investigating new biomarkers performance is needed.ObjectivesAssessment of diagnostic and predictor roles of prostate health index (PHI) and urokinase plasminogen activator (uPA) in PCa.Methods194 males with initial tPSA of 4–10 ng/mL were categorized into three groups: PCa, benign prostatic hyperplasia (BPH) and healthy control. Serum levels of tPSA, fPSA, p2PSA, and uPA were performed by ELISA with calculation of PHI as (p2PSA/fPSA) × √PSA.ResultsPHI and uPA were significantly higher in PCa patients relevant to BPH and healthy control (p ≤ 0.001). Both markers outperformed all assessed biomarkers and showed the highest area under the curve (AUC) in ROC curve analysis. Both were significantly higher in PCa patients with {Gleason score ≥ 7, late stages (cT2b,c; T3), LN extension and distant metastasis}relative to their counterparts. Additionally, PHI and uPA and were independent predictors of distant metastasis and Gleason score ≥ 7, while PHI was predictor of LN invasion (β = 0.25, p = 0.004).ConclusionPHI and uPA would be of potential value in discriminating between PCa, BPH and healthy men in addition, both are promising as independent predictors of adverse pathological features.     

Ultrasound Elastography of the Prostate Using an Unconstrained Modulus Reconstruction Technique: A Pilot Clinical Study

A novel full-inversion-based technique for quantitative ultrasound elastography was investigated in a pilot clinical study on five patients for non-invasive detection and localization of prostate cancer and quantification of its extent. Conventional-frequency ultrasound images and radiofrequency (RF) data (~5 MHz) were collected during mechanical stimulation of the prostate using a transrectal ultrasound probe. Pre and post-compression RF data were used to construct the strain images. The Young's modulus (YM) images were subsequently reconstructed using the derived strain images and the stress distribution estimated iteratively using finite element (FE) analysis. Tumor regions determined based on the reconstructed YM images were compared to whole-mount histopathology images of radical prostatectomy specimens. Results indicated that tumors were significantly stiffer than the surrounding tissue, demonstrating a relative YM of 2.5 ± 0.8 compared to normal prostate tissue. The YM images had a good agreement with the histopathology images in terms of tumor location within the prostate. On average, 76% ± 28% of tumor regions detected based on the proposed method were inside respective tumor areas identified in the histopathology images. Results of a linear regression analysis demonstrated a good correlation between the disease extents estimated using the reconstructed YM images and those determined from whole-mount histopathology images (r² = 0.71). This pilot study demonstrates that the proposed method has a good potential for detection, localization and quantification of prostate cancer. The method can potentially be used for prostate needle biopsy guidance with the aim of decreasing the number of needle biopsies. The proposed technique utilizes conventional ultrasound imaging system only while no additional hardware attachment is required for mechanical stimulation or data acquisition. Therefore, the technique may be regarded as a non-invasive, low cost and potentially widely-available clinical tool for prostate cancer diagnosis.     

DNA methylation profiles in African American prostate cancer patients in relation to disease progression

This study examined whether differential DNA methylation is associated with clinical features of more aggressive disease at diagnosis and prostate cancer recurrence in African American men, who are more likely to die from prostate cancer than other populations. Tumor tissues from 76 African Americans diagnosed with prostate cancer who had radical prostatectomy as their primary treatment were profiled for epigenome-wide DNA methylation levels. Long-term follow-up identified 19 patients with prostate cancer recurrence. Twenty-three CpGs were differentially methylated (FDR q ≤ 0.25, mean methylation difference ≥ 0.10) in patients with vs. without recurrence, including CpGs in GCK, CDKL2, PRDM13, and ZFR2. Methylation differences were also observed between men with metastatic-lethal prostate cancer vs. no recurrence (five CpGs), regional vs. local pathological stage (two CpGs), and higher vs. lower tumor aggressiveness (one CpG). These results indicate that differentially methylated CpG sites identified in tumor tissues of African American men may contribute to prostate cancer aggressiveness.     

Synthesis and evaluation of 18F-labeled CJ-042794 for imaging prostanoid EP4 receptor expression in cancer with positron emission tomography

The potent and selective prostanoid EP4 receptor antagonist CJ-042794 was radiolabeled with ¹⁸F, and evaluated for imaging EP4 receptor expression in cancer with positron emission tomography (PET). The fluorination precursor, arylboronic acid pinacol ester 4, was prepared in 4 steps with 42% overall yield. ¹⁸F-CJ-042794 was synthesized via a copper-mediated ¹⁸F-fluorination reaction followed by base hydrolysis, and was obtained in 1.5 ± 1.1% (n = 2) decay-corrected radiochemical yield. PET/CT imaging and biodistribution studies in mice showed that ¹⁸F-CJ-042794 was excreted through both renal and hepatobiliary pathways with significant retention in blood. The EP4-receptor-expressing LNCaP prostate cancer xenografts were clearly visualized in PET images with 1.12 ± 0.08%ID/g (n = 5) uptake value and moderate tumour-to-muscle contrast ratio (2.73 ± 0.22) at 1 h post-injection. However, the tumour uptake was nonspecific as it could not be blocked by co-injection of cold standard, precluding the application of ¹⁸F-CJ-042794 for PET imaging of EP4 receptor expression in cancer.     

Le test urinaire PCA3 : quelles perspectives ?

Since its introduction 10 years ago, the urinary PCA3 test was evaluated in several studies that allowed demonstration of its diagnostic value when predicting prostate biopsy outcome. Its good specificity, notably when compared to seric PSA, offers to the urologist the opportunity to better evaluate whether prostate biopsies are warranted, especially in patients with at least one set of previous negative biopsies. Several points remain to be determined such as its true influence on prostate decision making in clinical practice and the resulting medico-economic benefit. The place of the urinary PCA3 test among other developing prostate cancer biomarkers, notably PHI index and urinary TMPRSS2:ERG fusions, has also to be defined.