Safety and Efficacy Study of Neoadjuvant Radiohormonal Therapy for Oligometastatic Prostate Cancer: Protocol of an Open-Label, Dose-Escalation, Single-Centre Phase I/II Clinical Trial.

BACKGROUND: The optimal treatment for oligometastatic prostate cancer (OMPC) is still on its way. Accumulating evidence has proven the safety and feasibility of radical prostatectomy and local or metastasis-directed radiotherapy for oligometastatic patients. The aim of this trial is to demonstrate the safety and feasibility outcomes of metastasis-directed neoadjuvant radiotherapy (naRT) and neoadjuvant androgen deprivation therapy (naADT) followed by robotic-assisted radical prostatectomy (RARP) for treating OMPC. METHODS: The present study will be conducted as a prospective, open-label, dose-escalation, phase I/II clinical trial. The patients with oligometastatic PCa will receive 1 month of naADT, followed by metastasis-directed radiation and abdominal or pelvic radiotherapy. Then, radical prostatectomy will be performed at intervals of 4-8 weeks after radiotherapy, and ADT will be continued for 2 years. The primary endpoints of the study are safety profiles, assessed by the Common Terminology Criteria for Adverse Events (CTCAE) 5.0 grading scale, and perioperativemorbidities, assessed by the Clavien-Dindo classification system. The secondary endpoints include positive surgical margin (pSM), biochemical recurrence-free survival (bPFS), radiological progression-free survival (RPFS), postoperative continence, and quality of life (QoL) parameters. DISCUSSION: The optimal treatment for OMPC is still on its way, prompting investigation for novel multimodality treatment protocol for this patient population. Traditionally, radical prostatectomy has been recommended as one of the standard therapies for localized prostate cancer, but indications have expanded over the years as recommended by NCCN and EAU guidelines. RP has been carried out in some centres for OMPC patients, but its value has been inconclusive, showing elevated complication risks and limited survival benefit. Neoadjuvant radiotherapy has been proven safe and effective in colorectal cancer, breast cancer and other various types of malignant tumors, showing potential advantages in terms of reducing metastatic stem-cell activity, providing clinical downstaging, and reducing potential intraoperative risks. Existing trials have shown that naRT is well tolerated for high-risk and locally-advanced prostate cancer. In this study, we hope to further determine the optimal irradiation dose and patient tolerance for genitourinary, gastrointestinal and systemic toxicities with the design of 3+3 dose escalation; also, final pathology can be obtained following RP to further determine treatment response and follow-up treatment plans. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900025743. http://www.chictr.org.cn/showprojen.aspx?proj=43065.

Association between schizophrenia and prostate cancer risk: Results from a pool of cohort studies and Mendelian randomization analysis.

BACKGROUND: Observational studies analyzing the risk of prostate cancer in schizophrenia patients have generated mixed results. We performed a meta-analysis and a Mendelian randomization (MR) analysis to evaluate the relationship and causality between schizophrenia and the risk of prostate cancer. METHODS: A comprehensive and systematic search of cohort studies was conducted, and a random-effects model meta-analysis was performed to calculate the standardized incidence ratios (SIRs) for prostate cancer incidence among schizophrenia patients versus the general population. To investigate the correlation between genetically-predicted schizophrenia and prostate cancer risk, we used summary statistics from the Prostate Cancer Association Group to Investigate Cancer Associated Alterations in the Genome (PRACTICAL) consortium (61,106 controls and 79,148 cases), and 75 schizophrenia-associated single nucleotide polymorphisms (SNP) from European descent as the instrumental variable. RESULTS: In the meta-analysis of 13 cohort studies with 218,076 men involved, a decreased risk of prostate cancer was observed among schizophrenia patients [SIR 0.610; 95% confidence interval (CI) 0.500-0.740; p < 0.001] with significant heterogeneity (I2 = 83.3%; p < 0.001). However, MR analysis did not sustain the link between genetically-predicted schizophrenia and prostate cancer [odds ratio (OR) 1.033; 95% CI 0.998-1.069; p = 0.065]. The result was robust against extensive sensitivity analyses. CONCLUSIONS: Our study indicated a decreased risk of prostate cancer in schizophrenia patients through meta-analysis, while MR analysis did not support the connection between schizophrenia and prostate cancer. Due to the interaction of genetic variants between binary exposures, we need to be cautious in interpreting and presenting causal associations. Moreover, further research is needed to investigate underlying factors that might link schizophrenia to the risk of prostate cancer.

Cause-specific mortality of low and selective intermediate-risk prostate cancer patients with active surveillance or watchful waiting.

BACKGROUND: Active surveillance or watchful waiting (AS/WW) is increasingly being used as an alternative strategy to radical prostatectomy or radiation therapy for appropriately selected patients with prostate cancer (PCa). However, the prognosis of low-risk and selective intermediate-risk PCa patients after AS/WW is poorly defined. In this study we reviewed the patients registered in the Surveillance, Epidemiology, and End Results (SEER) Program to establish a competing risk nomogram for the prediction of prostate cancer-specific mortality (PCSM). METHODS: The information of patients undergoing AS/WW in the SEER program from 2004 to 2015 was obtained. All patients were ISUP (International Society of Urological Pathology) grade 1 or 2 PCa and also fulfilled the National Comprehensive Cancer Network's definition of low-risk PCa [prostate specific antigen (PSA) <10 ng/mL and cT2aN0M0 or less)]. A competing risk nomogram was used to analyze the association of tumor characteristics with PCSM and non-PCSM among the PCa patients with AS/WW. All cases were randomly divided into a training cohort and a validation cohort (1:1). A competing risk nomogram was constructed to predict PCSM in PCa patients with AS/WW. The performance of the PCSM nomogram was evaluated using the concordance index (C-index) and calibration curve. RESULTS: A total of 30,538 PCa patients were identified as low risk or selective intermediate risk with AS/WW. The 10-year cumulative incidence of death from prostate cancer and death from other cause were 2.8% (95% CI: 2.4-3.1%) and 19.3% (95% CI: 17.8-20.5%), respectively. Variables associated with PCSM included age, marital status, PSA, and ISUP grade. The PCSM nomogram had a good performance in both the training and validation cohorts, with a C-index of 0.744 (95% CI: 0.700-0.781, P<0.001) and 0.738 (95% CI: 0.700-0.777, P<0.001), respectively. CONCLUSIONS: Overall, the prognosis was favorable for the low- and selective intermediate-risk PCa patients with AS/WW. The competing risk nomogram yielded a good performance in identifying subgroups of patients with a higher risk of PCSM and potential candidates for AS/WW.

A 10-gene signature as a predictor of biochemical recurrence after radical prostatectomy in patients with prostate cancer and a Gleason score ≥7.

The time and speed of biochemical recurrence (BCR) of prostate cancer (PCa) after radical prostatectomy (RP) is highly variable. Stratification methods based on TNM staging and Gleason score (GS) do not allow the identification of patients at risk of BCR following RP. Therefore, the aim of the present study was to identify molecular signatures that can predict BCR risk effectively and facilitate treatment-related decisions for patients with PCa. RNA sequencing data and corresponding clinical data were downloaded from The Cancer Genome Atlas (TCGA) and Oncomine databases. Bioinformatics analysis was performed to identify differentially expressed genes in patients with GS=6 and GS ≥7. Cox regression models were used to determine the PCa signature (PCasig) and a clinical nomogram for the prediction of BCR. The performance of nomograms was assessed using time-dependent receiver operating characteristic curves and the concordance index (C-index). A PCasig comprising 10 genes, including SEMG2, KCNJ16, TFAP2B, SYCE1, KCNU1, AFP, GUCY1B2, GRIA4, NXPH1 and SOX11, was significantly associated with BCR, which was identified in TCGA cohort [hazard ratio (HR), 5.18; 95% CI, 3.241-8.272; C-index, 0.777] and validated in the Oncomine cohort (HR, 2.78; 95% CI, 1.39-5.54; C-index, 0.66). The expression levels of SEMG2, KCNJ16 and TFAP2B were downregulated in patients with GS ≥7. The expression levels of SYCE1, KCNU1, AFP, GUCY1B2, GRIA4, NXPH1 and SOX11 were upregulated in patients with GS ≥7. The clinical nomogram was constructed based on the GS and pathologic T stage (HR, 4.15; 95% CI, 1.39-5.54; C-index, 0.713). The addition of the PCasig to the clinical nomogram significantly improved prognostic value (HR, 7.25; 95% CI, 4.54-11.56; C-index, 0.782) with an net reclassification improvement of 75.3% (95% CI, 46.8-104.6%). Furthermore, the endogenous expression of each gene in the PCasig was measured in five PCa cell lines and in normal prostate cells, and these genes exhibited different expression levels relative to one another. In conclusion, an PCasig was identified by mining TCGA and successfully validated in an Oncomine cohort. This PCasig was an independent prognostic factor with a greater prognostic value for all patients regardless of GS than traditional clinical variables, which can improve the performance of clinical nomograms in predicting BCR of patients with GS ≥7.

A new risk stratification system of prostate cancer to identify high-risk biochemical recurrence patients.

BACKGROUND: Biochemical recurrence (BCR) is considered a decisive risk factor for clinical recurrence and the metastasis of prostate cancer (PCa). Therefore, we developed and validated a signature which could be used to accurately predict BCR risk and aid in the selection of PCa treatments. METHODS: A comprehensive genome-wide analysis of data concerning PCa from previous datasets of the Cancer Genome Atlas (TCGA) and the gene expression omnibus (GEO) was performed. Lasso and Cox regression analyses were performed to develop and validate a novel signature to help predict BCR risk. Moreover, a nomogram was constructed by combining the signature and clinical variables. RESULTS: A total of 977 patients were involved in the study. This consisted of patients from the TCGA (n=405), GSE21034 (n=131), GSE70770 (n=193) and GSE116918 (n=248) datasets. A 9-mRNA signature was identified in the TCGA dataset (composed of C9orf152, EPHX2, ASPM, MMP11, CENPF, KIF4A, COL1A1, ASPN, and FANCI) which was significantly associated with BCR (HR =3.72, 95% CI: 2.30-6.00, P<0.0001). This signature was validated in the GSE21034 (HR =7.54, 95% CI: 3.15-18.06, P=0.019), GSE70770 (HR =2.52, 95% CI: 1.50-4.22, P=0.0025) and GSE116918 datasets (HR =4.75, 95% CI: 2.51-9.02, P=0.0035). Multivariate Cox regression and stratified analysis showed that the 9-mRNA signature was a clinical factor independent of prostate-specific antigen (PSA), Gleason score (GS), or AJCC T staging. The mean AUC for 5-year BCR-free survival predictions of the 9-mRNA signature (0.81) was higher than the AUC for PSA, GS, or AJCC T staging (0.52-0.73). Furthermore, we combined the 9-mRNA signature with PSA, GS, or AJCC T staging and demonstrated that this could enhance prognostic accuracy. CONCLUSIONS: The proposed 9-mRNA signature is a promising biomarker for predicting BCR-free survival in PCa. However, further controlled trials are needed to validate our results and explore a role in individualized management of PCa.