High-risk Prostate Cancer Patients Research Articles

Predictors of radiation-induced late rectal toxicity in prostate cancer treatment: a volumetric and dosimetric analysis.

Prostate cancer (PCa) is a prevalent malignancy in European men, often treated with radiotherapy (RT) for localized disease. While modern RT achieves high success rates, concerns about late gastrointestinal (GI) toxicities persist. This retrospective study aims to identify predictors for late GI toxicities following definitive conventionally fractionated external beam RT (EBRT) for PCa, specifically exploring the dose to the rectal wall. A cohort of 96 intermediate- to high-risk PCa patients underwent EBRT between 2008 and 2016. Rectum and rectum wall contours were delineated, and 3D dose matrices were extracted. Volumetric and dosimetric indices were computed, and statistical analyses were performed to identify predictors using the Mann-Whitney U-rank test, logistic regression, and recursive feature elimination. In our cohort, 15 out of 96 patients experienced grade II late proctitis. Our analysis reveals distinct optimal predictors for rectum and rectum wall (RW) structures varying with α/β values (3.0 and 2.3 Gy) across prescribed doses of 68 to 76 Gy. Despite variability, RW predictors demonstrate greater consistency, notably V68Gy[%] to V74Gy[%] for α/β 3.0 Gy, and V68Gy[%] to V70Gy[%] for α/β 2.3 Gy. The model with α/β 2.3 Gy, featuring RW volume receiving 70 Gy (V70Gy[%]), stands out with a BIC value of 62.92, indicating its superior predictive effectiveness. Finally, focusing solely on the rectum structure, the V74Gy[%] emerges the best predictor for α/β 3.0 Gy, with a BIC value of 66.73. This investigation highlights the critical role of V70Gy[%] in the rectum wall as a robust predictor for grade II late gastrointestinal (GI) toxicity following external beam radiation therapy (EBRT) for prostate cancer (PCa). Furthermore, our findings suggest that focusing on the rectum wall specifically, rather than the entire rectum, may offer improved accuracy in assessing proctitis development. A V70Gy (in EQD2 with α/β 2.3 Gy) of ≤5% and if possible ≤1% for the rectal wall should be achieved to minimize the risk of late grade II proctitis.

Predicting contralateral extraprostatic extension in unilateral high-risk prostate cancer: a multicentric external validation study.

Accurate prediction of extraprostatic extension (EPE) is crucial for decision-making in radical prostatectomy (RP), especially in nerve-sparing strategies. Martini et al. introduced a three-tier algorithm for predicting contralateral EPE in unilateral high-risk prostate cancer (PCa). The aim of the study is to externally validate this model in a multicentric European cohort of patients. The data from 208 unilateral high-risk PCa patients diagnosed through magnetic resonance imaging (MRI)-targeted and systematic biopsies, treated with RP between January 2016 and November 2021 at eight referral centers were collected. The evaluation of model performance involved measures such as discrimination (AUC), calibration, and decision-curve analysis (DCA) following TRIPOD guidelines. In addition, a comparison was made with two established multivariable logistic regression models predicting the risk of side specific EPE for assessment purposes. Overall, 38%, 48%, and 14% of patients were categorized as low, intermediate, and high-risk groups according to Martini et al.'s model, respectively. At final pathology, EPE on the contralateral prostatic lobe occurred in 6.3%, 12%, and 34% of patients in the respective risk groups. The algorithm demonstrated acceptable discrimination (AUC 0.68), comparable to other multivariable logistic regression models (p = 0.3), adequate calibration and the highest net benefit in DCA. The limitations include the modest sample size, retrospective design, and lack of central revision. Our findings endorse the algorithm's commendable performance, supporting its utility in guiding treatment decisions for unilateral high-risk PCa patients.

Proteomic Identification of Small Extracellular Vesicle Proteins LAMB1 and Histone H4 for Prostate Cancer Diagnosis and Risk Stratification.

Diagnosis and stratification of prostate cancer (PCa) patients using the prostate-specific antigen (PSA) test is challenging. Extracellular vesicles (EVs), as a new star of liquid biopsy, has attracted interest to complement inaccurate PSA screening and invasiveness of tissue biopsy. In this study, a panel of potential small EV (sEV) protein biomarkers is identified from PCa cell lines using label-free LC-MS/MS proteomics. These biomarkers underwent further validation with plasma and urine samples from different PCa stages through parallel reaction monitoring-based targeted proteomics, western blotting, and ELISA. Additionally, a tissue microarray containing cancerous and noncancerous tissues is screened to provide additional evidence of selected sEV proteins associated with cancer origin. Results indicate that sEV protein LAMB1 is highly expressed in human plasma of metastatic PCa patients compared with localised PCa patients and control subjects, while sEV protein Histone H4 is highly expressed in human urine of high-risk PCa patients compared to low-risk PCa patients and control subjects. These two sEV proteins demonstrate higher specificity and sensitivity than the PSA test and show promise for metastatic PCa diagnosis, progression monitoring, and risk stratification.

The 2012 Briganti nomogram predicts disease progression after surgery in high-risk prostate cancer patients

ABSTRACT Objectives We tested whether the 2012 Briganti nomogram for the risk of pelvic lymph node invasion (PLNI) may represent a predictor of disease progression after surgical management in high-risk (HR) prostate cancer (PCa) patients according to the European Association of Urology. Methods Between January 2013 and December 2021, HR PCa patients treated with robot-assisted radical prostatectomy (RARP) and extended pelvic lymph node dissection (ePLND) were identified. The 2012 Briganti nomogram was evaluated as a continuous and categorical variable, which was dichotomized using the median. The risk of disease progression, defined as the event of biochemical recurrence and/or local recurrence/distant metastases was assessed by Cox regression models. Results Overall, 204 patients were identified. The median 2012 Briganti nomogram score resulted 12.0% (IQR: 6.0–22.0%). PLNI was detected in 57 (27.9%) cases. Compared to patients who had preoperatively a 2012 Briganti nomogram score ≤12%, those with a score >12% were more likely to present with higher percentage of biopsy positive cores, palpable tumors at digital rectal examination, high-grade cancers at prostate biopsies, and unfavorable pathology in the surgical specimen. At multivariable Cox regression analyses, disease progression, which occurred in 85 (41.7%) patients, was predicted by the 2012 Briganti nomogram score (HR: 1.02; 95%CI: 1.00–1.03; p = 0.012), independently by tumors presenting as palpable (HR: 1.78; 95%CI: 1.10.2.88; p = 0.020) or the presence of PLNI in the surgical specimen (HR: 3.73; 95%CI: 2.10–5.13; p = 0.012). Conclusions The 2012 Briganti nomogram represented an independent predictor of adverse prognosis in HR PCa patients treated with RARP and ePLND. As the score increased, so patients were more likely to experience disease progression, independently by the occurrence of PLNI. The association between the nomogram, unfavorable pathology and tumor behavior might turn out to be useful for selecting a subset of patients needing different treatment paradigms in HR disease.

Abstract CT023: Prostate cancer in situ autovaccination with the intratumoral viral mimic poly-ICLC: Making a cold tumor hot

Abstract PURPOSE To test the safety of sequential intratumoral plus systemic intramuscular injection of poly-ICLC, and its efficacy in priming antitumor immune responses in patients with prostate cancer (PCa). EXPERIMENTAL PROCEDURES This is an open-label dose-escalating phase 1 neoadjuvant clinical trial of poly-ICLC (NCT03262103) in 12 patients diagnosed with clinically localized PCa with plans to undergo radical prostatectomy (RP). Poly-ICLC was administered intratumorally (Artemis MRI-TRUS-guided) and intramuscularly (e.g., deltoid muscle). Comprehensive transcriptional profiling of tissues, phenotypic and transcriptional analysis of longitudinally collected peripheral blood, and analysis of the prostate tumor microenvironment (TME) were performed before and after poly-ICLC treatment in order to identify innate and adaptive antitumor immune responses within the tumor and in peripheral blood. This trial is the first to use human intratumoral immunotherapy instead of systemic immunomodulation for high-risk PCa patients. RESULTS Poly-ICLC was well tolerated (safe) in all 12 patients. There were no dose-limiting toxicities or TEAE (treatment-emergent adverse events) withdrawals during treatment. Eight of 10 evaluable patients (80%) had undetectable PSA (<0.1 ng/ml) at 1 year of follow-up post-RP. Eight of 12 evaluable patients (66.7%) and 7 of 10 patients (70%) with biopsy Gleason 8-10 had a lower Gleason score in the post-treatment RP specimen. Transcriptome profiling of paired biopsy and RP specimens showed significant upregulation of gene signatures associated with immune cell infiltration and TP53-associated metabolic genes, but downregulation of gene signatures associated with metastasis and DNA replication. Genes upregulated by poly-ICLC were associated with a good prognosis. Treatment with poly-ICLC increased systemic immune responses, as demonstrated by an increase in cytolytic signatures, T- and NK-cell signatures, and NK-cell subsets in the blood. Multiplex immunohistochemistry analysis revealed a significant increase in the densities of CD4- and CD8-T cells and B cells, as well as evidence of tertiary lymphoid structures (TLS) within the TME of post-treatment RP specimens compared to baseline. CONCLUSIONS Poly-ICLC treatment can reliably transform the cold TME of PCa into a hot, immune-enhanced ecosystem. The identified baseline and response biomarkers, tertiary lymphoid structures, potential clinical benefit, and immunologic correlates require validation in larger studies. Citation Format: Sujit S. Nair, Dimple Chakravarty, Sreekumar Balan, Alexander Hakansson, Manuel Duval, Elai Davicioni, Yang Liu, Swati Bhardwaj, Tin Htwe Thin, Monica Garcia-barros, Kenneth Haines, Majd Al Shaarani, Rachel Weil, Marcia Meseck, Parita Ratnani, Monali Fatterpekar, Ivan Jambor, Elena Gonzalez-Gugel, Adam Farkas, Vinayak Wagaskar, Kacie Schlussel, Cristina Pasat-karasik, Kamala Bhatt, Zachary Dovey, Adriana Pedraza, Akriti Gupta, Dara Lundon, Ante Peros, Sneha Parekh, Lily Davenport, Xiangfu Zhang, Raghav Gupta, Macy Robison, Cynthia Knauer, Ethan Ellis, Dmitry Rykunov, Boris Reva, Babu Padanilam, Matthew D. Galsky, Rachel Brody, Mani Menon, Andres Salazar, Nina Bhardwaj, Ashutosh K. Tewari. Prostate cancer in situ autovaccination with the intratumoral viral mimic poly-ICLC: Making a cold tumor hot [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT023.

Initial [18F]DCFPyL PET/CT in treatment-naïve prostate cancer: correlation with post-ADT PSA outcomes and recurrence.

Positron emission tomography (PET) with prostate-specific membrane antigen (PSMA) targeting tracers has emerged as a valuable diagnostic tool for prostate cancer (PCa), androgen deprivation therapy (ADT) stands as the cornerstone treatment for advanced PCa, yet forecasting the response to hormonal therapy poses a significant clinical hurdle. In a prospective cohort of 86 PCa patients undergoing short-term ADT, this study evaluated the prognostic potential of [18F]DCFPyL PET/CT scans. Comprehensive data encompassing clinical profiles, baseline prostate-specific antigen (PSA) levels, and imaging metrics were assessed. We developed predictive models for assessing decreases in PSA levels (PSA50 and PSA70) based on a combination of PET-related parameters and clinical factors. Kaplan-Meier survival analysis was utilized to ascertain the prognostic value of PET-based metrics. In this study, elevated [18F]DCFPyL uptake within the primary tumor, as indicated by a SUV ≥ 6.78 (p = 0.0024), and a reduction in the tumor volume (TV) of primary PSMA-avid tumor with PSMA-TV < 41.96 cm3 (p = 0.038), as well as an increased burden of metastatic PSMA-avid tumor, with PSMA-TV (PSMA-TV ≥ 71.39 cm3) (p = 0.012) were identified in association with diminished progression-free survival (PFS). PET and clinical parameters demonstrated constrained predictive capacity for PSA50 response as indicated by an area under the curve (AUC) of 0.442. Our study revealed that pretreatment [18F]DCFPyL uptake in primary or metastatic tumor sites is prognostically relevant in high-risk PCa patients undergoing ADT. Further research is needed to develop robust predictive models in this multifaceted landscape of PCa management.

(O-28) CHRONOLOGY OF ENDOGENOUS TESTOSTERONE RECOVERY AFTER DISCONTINUATION OF ANDROGEN DEPRIVATION THERAPY - RESULTS FROM A PROSPECTIVE ANALYSIS

Abstract I - Testosterone recovery after different androgen deprivation therapy regimens for prostate cancer varies widely (7-96%) in the literature, with data coming mainly from retrospective studies. O - Evaluate testosterone recovery after ADT cessation prospectively. M - This secondary analysis of a neoadjuvant ADT study for high-risk prostate cancer patients collected total testosterone (TT) levels at baseline and up to 12 months post-ADT cessation. Three recovery outcomes were assessed: return to non-castrate (TT &amp;gt; 50 ng/dL), normal (TT ≥ 300 ng/dL), and baseline (BTB - TT ≥ baseline). A time-to-event analysis and multivariate analysis were conducted. R - 1-year follow-up data from 53 patients (60 with at least 1 follow-up data. Mean age was 64.6 (± 5.89), 28% had diabetes (DM), and 61% had hypertension (HTN). Mean TT levels were 450 ng/dL (± 170) at baseline, 112.7 ± 96.9 at 3 months, 208.5 ± 197 at 6 months, 341.8 ± 172 at 9 months, and 381.1 ± 166 at 12 months. Figure 1 shows the cumulative incidence of each outcome over time. The median time to achieve T &amp;gt; 50 was 5 months, for T &amp;gt; 300 it was 9.1 months, and for BTB it was 13.1 months. At 1 year post-ADT discontinuation, 98.1% had returned to TT &amp;gt; 50, 79.5% had TT &amp;gt; 300, and 33.9% had returned to baseline level. In a multivariate analysis including DM, HTN, age, and baseline T, only baseline T was associated with a higher chance of recovery to normality (baseline T &amp;gt; 450-88.5% vs. 46.9%, HR: 3.06, p &amp;lt; 0.05). C - In this prospective analysis, after discontinuing 3-month neoadjuvant ADT, most achieved normal T levels (80%) after 1 year, but less than half recovered to baseline levels. Cumulative Incidence of each outcome Financing Janssen-Cilag Farmacêutica Ltda.

Abstract 4205: Investigating micro-environmental changes in a syngeneic radio-recurrent prostate cancer model

Abstract Approximately 1 in 8 men in Canada will be diagnosed with prostate cancer (PCa) in their lifetime, with ~20% presenting with high-risk disease. A standard treatment is radiotherapy (RT) and while many patients respond well to RT, up to 40% of men with high-risk disease can recur, often within the prostate. It can be challenging to salvage prostate relapses due to the morbidity of re-irradiation and the high rate of subsequent progression. The tumor micro-environment (TME) is altered after radiotherapy with increased immune-suppressor and immune-stimulatory effects occurring concurrently. Therapies capitalizing on these changes in the TME might provide an advantage to tackling radiation-recurrent cancer. Identifying TME changes in radio-recurrent PCa is the first step; however, existing PCa animal models do not accurately model the TME. Our collaborator’s lab has created the DVL3 mouse model with a clinically relevant TME. It forms tumors with distinct glandular morphology and displays micro-environmental responses to RT like what is seen in high-risk PCa patients, making this model an innovative tool for investigating radio-recurrence. The objective of this study is to create a radio-recurrent DVL3 PCa cell line to explore changes in the TME both in vitro and in vivo via orthotopic injection. To generate the radio-recurrent model, the DVL3 Parental cells (DVL3-Par) underwent a conventionally fractionated RT schedule (78Gy/39fx), herein referred to as DVL3-CF cells. The first part of the project involves in vitro characterization. Radiation resistance was evaluated via clonogenic assay which demonstrated a significant increase in clonogenic survival in the DVL3-CF cells relative to DVL3-Par. Characterization of DVL3-CF cells demonstrates that they are more proliferative at baseline, they recover quicker following G2/M blocks, they have decreased senescence following high dose radiation, and they are more invasive in vitro. The second part of the project evaluates the radio-recurrent model in vivo using an orthotopic mouse model as this best emulates the TME and clinical tumor progression. Parental and CF cells will be injected orthotopically into the prostate of C57/BL-6 mice and monitored for growth by MRI which will provide information on tumor volume as well as vasculature. At the time of sacrifice, the prostate and draining lymph nodes will be cryo-preserved and formalin fixed for downstream histological analysis. Transcriptional analyses, MRI data, and histological analysis of the tumors and draining lymph nodes will be compared across the radio-recurrent model and its parental cell line to evaluate environmental changes and potentially implicated mechanisms. This study will elucidate some of the complex interactions that are occurring within the TME of radio-recurrent PCa, increasing our understanding of mechanisms of radio-recurrence. Citation Format: Stephanie D. White, Xiaoyong Huang, Ian Mills, Stanley K. Liu. Investigating micro-environmental changes in a syngeneic radio-recurrent prostate cancer model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4205.

Abstract 471: Attenuation of circulating miR-17-5p, miR-20b-5p, and miR-106a-5p in low-risk prostate cancer patients following proton therapy

Abstract Introduction: Liquid biopsies offer a novel approach to diagnose, predict cancer outcomes, and monitor treatment response by analyzing tumor-derived substances. Circulating cell-free microRNAs (miRNAs) show clinical promise as biomarkers within prostate cancer (PCa) and have been implicated with PCa prognosis and outcomes. However, their potential for monitoring and assessing radiotherapy (RT) treatment response remains understudied. Understanding miRNA expression changes during RT is crucial, as they impact RT efficacy by directly affecting genes and proteins within RT-response pathways. Aim: This study aimed to profile the expression of three oncogenes, miR-17-5p, miR-20b-5p, and miR-106a-5p and to determine their association with PCa risk groups in patients receiving proton therapy (PT). Patients and Methods: Plasma was obtained from the University of Florida Health Proton Therapy Institute Outcomes Tracking Protocol biobank. Plasma was collected from men diagnosed with localized PCa without metastatic disease at three time points: prior to PT (PRE-PT), at 4 weeks following the start of PT (4WKSPD1), and at 8 weeks following the start of PT (8WKSPD1). The pilot study consisted of 38 patients, with 23 categorized as low-risk and 15 categorized as high-risk for PCa. MiRNA expression levels were evaluated using reverse transcription-polymerase chain reaction and quantified using the Livak method. Results: The study revealed a downregulation of miR-17-5p in response to PT, with median gene expression levels decreasing from 0.73 at PRE-PT to 0.587 at 8WKSPD1. Low-risk PCa patients also showed distinct miRNA expression changes with all three miRNAs (miR-17-5p, miR-20b-5p, and miR-106a-5p) downregulated from 0.953, 1.037, and 1.010 at PRE-PT to 0.398, 0.216, and 0.298 at 8WKSPD1, respectively. Statistical analysis using a Kruskal-Wallis test followed by a Dunn's post-hoc test identified significant differences (p=0.035) specifically between PRE-PT and 8WKSPD1 for miR-17-5p. Conclusion: The study revealed that PT led to a time-dependent reduction in miRNA levels, indicating a higher responsiveness in low-risk compared to high-risk PCa patients. This differential response highlights miR-17-5p, miR-20b-5p, and miR-106a-5p as potential PT response biomarkers, with clinical implications for personalizing PCa treatment. These results underscore the necessity for further validation of these miRNAs to maximize their clinical utility. Citation Format: Johnny Velasquez, Curtis Bryant, Nancy Mendenhall, Luisel Ricks-Santi. Attenuation of circulating miR-17-5p, miR-20b-5p, and miR-106a-5p in low-risk prostate cancer patients following proton therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 471.

A study on the impact of marital status on the survival status of prostate cancer patients based on propensity score matching

Marital status is an independent prognostic factor for survival in many types of cancers, but its prognostic impact on patients with prostate cancer (PCa) has not been established. The aim of this study was to explore the independent prognostic factors of PCa and to investigate the effect of marital status on survival outcomes in patients with different stratified by PCa. Using the surveillance, epidemiology, and end results (SEER) database, we collected data on 584,655 PCa patients diagnosed between 1975 and 2019. Marital status was classified as married, divorced, widowed, and single. We used the Kaplan–Meier analysis and single multivariate Cox proportional hazards regression analysis to determine the effect of marital status on overall survival (OS) and cancer-specific survival (CSS). In addition, we performed subgroup analyses for different ages, Gleason score and PSA values, and performed a 1:1 propensity score matching (PSM) to reduce the impact of confounding factors to obtain more accurate matching results. According to our findings, marital status was an independent prognostic factor for the survival of PCa patients and a better prognosis of married patients. Moreover, we also found that factors such as age, TNM stage, Gleason score, and PSA concentration were also considered as important predictors for the prognosis of PCa. The above findings can facilitate early detection and treatment of high-risk PCa patients, prolong their life and reduce family burden.

Performance of the F-PSMA 1007 PET/CT for high-risk prostate cancer staging: Experience from a Latin American reference center.

286 Background: Diagnostic staging in high-risk prostate cancer patients seeks to define the local extent of the disease as well as determine the presence of lymph nodes and distant metastases. Molecular imaging, such as PET PSMA, provides higher sensitivity and specificity for the detection of nodal and distant metastases compared to conventional imaging. 18F-PSMA-1007 is radiotracer that represents a cost-effective alternative to 68Ga-PSMA-11, although evidence is limited. We aim to describe the performance of PSMA-1007 in the staging of patients with high risk for prostate cancer in a Latin America reference center. Methods: We performed a cross-sectional study that included prostate cancer patients who underwent 18F-PSMA1007 PET/CT for initial staging in our center of reference between 2020-2023. Descriptive analysis was performed with frequencies for discrete variables, and central tendency and dispersion measures for continuous variables. High risk was defined using the NCCN prostate cancer guidelines. Contingency tables were designed to evaluate associations between groups. To compare categorical variables, we use Chi-square and ANOVA for continuous variables. This analysis was performed using Jamovi 2.3.21 statistical software. Results: Two hundred and seventeen patients were included. The median age was 67 years. The median PSA distribution was 12 ng/ml. The most frequent Gleason group was group 4 (42,7%), followed by group 3 (25,5%). The most prevalent results on the PET pattern are presented in Table. 32% of the patients presented positive lymph node findings. Before the F-PSMA 1007 PET/CT, 24% of the patients had lymph node involvement identified and 33.2% had negative lymph nodes with conventional imaging. These values changed to 39% and 56% respectively, with the F-PSMA 1007 PET/CT. Bone was the most frequent metastasis site (14,3%), followed by extrapelvic lymph node metastasis (12%). A favorable correlation between higher PSA levels and stratified risk assessment by PSMA pattern was evident (p&lt; 0.001). Conclusions: 18F-PSMA-1007 is an innovative radiotracer that can be used to evaluate the extension of prostate cancer involvement. Future studies with prospective cohorts should be carried out to establish analyses between 18F-PSMA-1007 use and its influence on the oncological management of these patients.[Table: see text]

Improving the identification of high-risk non-metastatic castration-resistant prostate cancer patients in clinical practice.

Non-metastatic castration-resistant prostate cancer (nmCRPC) represents a challenging disease state in prostate cancer care. nmCRPC patients with a high risk of progression to metastatic disease who are identified by a prostate-specific antigen doubling time (PSADT) ≤10 months are eligible for treatment with the novel androgen receptor inhibitors (ARIs), shown to delay disease progression and extend survival. However, nmCRPC is often unexploited in clinical practice due to a lack of standardization in the methodology and in the tools used for its identification. In this article, a group of Urology and Oncology specialists with acknowledged expertise in prostate cancer reviews the state of the art in the management of high-risk nmCRPC patients, identifies gaps and unmet needs, and proposes strategies to optimize the identification of this patient subgroup in the clinical practice and improve their health outcomes.

Clinical value of 18F-PSMA-1007 PET/MRI in primary staging of patients with intermediate- to high-risk prostate cancer.

To assess the utility of 18F-PSMA-1007 PET/MRI in initial staging of intermediate- to high-risk prostate cancer (HRPCa). A total of 46 patients with pathologically verified intermediate and/or HRPCa who underwent 18F-PSMA-1007 PET/MRI with dedicated pelvic high-resolution multiparametric MRI (mpMRI) were included. PET/MRI showed 100% sensitivity (SN), specificity (SP), positive predictive value (PPV), negative predictive value (NPV), and accuracy in detecting seminal vesicle (SV) and rectal invasion, versus 87.5%, 100%, 100% 93.8%, 95.7% and 50%, 100%,100%, 95.5%, and 95.7% for mpMRI respectively. However, PET/MRI had poor SN (40% and 0%) but high SP (94.4% and 100%) in detection of UB and neurovascular bundle (NV) invasion compared to 100% SN and SP for mpMRI. PET/MRI demonstrated stronger TNM staging agreement with the gold standard than mpMRI-WBMRI. It demonstrated concordance with T, N, and M stages in 40, 41, and 36 patients (k 0.84, 0.60, and 0.68, respectively) versus 29, 33, and 31 patients (k 0.54, 0.22, and 0.50) with accurate over all staging of 38/46 patients versus 30/46 patients (K 0.52 versus 0.22). 18F-PSMA-1007 PET/MRI is a promising imaging modality with high diagnostic accuracy in staging intermediate- and HRPCa; it improves local tumour evaluation and provides precise TNM staging. 18F-PSMA-1007 PET/MRI could have high diagnostic accuracy as shown in the current study for staging HRPCa patients that is crucial for treatment selection. We think that our study will contribute to the body of knowledge and improve the literature surrounding the clinical uses of integrated 18F-PSMA-1007 PET/MRI.

Early change in apparent diffusion coefficient as a predictor of response to neoadjuvant androgen deprivation and external beam radiation therapy for intermediate- to high-risk prostate cancer

To determine the role of serial apparent diffusion coefficient (ADC) as a biomarker for response to neoadjuvant androgen deprivation therapy (nADT) followed by external beam radiation therapy (EBRT) in intermediate- to high-risk prostate cancer (PCa) patients. This Health Insurance Portability and Accountability Act (HIPAA)-compliant, institutional review board (IRB)-approved prospective study included 12 patients with intermediate- to high-risk PCa patients prior to nADT and EBRT, who underwent serial serum prostate-specific antigen (PSA) and multiparametric prostate magnetic resonance imaging (mpMRI) at baseline (BL), 8-weeks after nADT initiation (time point [TP]1), 6-weeks into EBRT delivery (TP2), and 6-months after nADT initiation (TP3). Tumour volume (tVOL) and tumour and normal tissue ADC (tADC and nlADC) were determined at all TPs. tADC and nlADC dynamics were correlated with post-treatment PSA using Pearson's correlation coefficient. Paired t-tests compared pre/post-treatment ADC. There was a sequential decrease in PSA at all TPs, reaching their lowest values at TP3 post-treatment completion. Mean tADC increased significantly from baseline to TP1 (917.8±107.7×10-6 versus 1033.8±139.3×10-6 mm2/s; p<0.01), with no subsequent change at TP2 or TP3. Both percentage and absolute change in tADC from BL to TP1 correlated with post-treatment PSA (r=-0.666, r=-0.674; p=0.02). Post-treatment PSA in good responders (<0.1 ng/ml) versus poor responders (≥ 0.1 ng/ml) was associated with a greater increase in tADC from BL to TP1 (169.2±122.4×10-6 versus 22.9±75.5×10-6 mm2/s, p=0.03). This pilot study demonstrates the potential for early ADC metrics as a biomarker of response to nADT and EBRT in intermediate to high-risk PCA.

External validation of an algorithm to personalize nerve sparing approaches during robot-assisted radical prostatectomy in men with unilateral high-risk prostate cancer.

Limited evidence exists about preserving neurovascular bundles during radical prostatectomy (RP) for high-risk prostate cancer (HRPCa) patients. Hence, we validated an existing algorithm predicting contralateral extraprostatic extension (cEPE) risk in unilateral high-risk cases. This algorithm aims to assist in determining the suitability of unilateral nerve-sparing RP. Among 264 patients, 48 (18%) had cEPE. The risk of cECE varied: 8%, 17.2%, and 30.8% for the low, intermediate, and high-risk groups, respectively. Despite a higher risk of cECE among individuals classified as low-risk in the development group compared to the validation group, our algorithm's superiority over always/never nerve-sparing RP was reaffirmed by decision curve analysis. Therefore, we conclude that bilateral excision may not always be justified in men with unilateral HRPCa. Instead, decisions can be based on our suggested nomogram.

Timing of High-Dose-Rate Brachytherapy With External Beam Radiation Therapy in Patients With Intermediate- and High-Risk Localized Prostate Cancer and Its Effects on Toxicity and Quality of Life: A Randomized Controlled Trial (THEPCA)

BackgroundHDR brachytherapy(HDR-BT) and external beam radiotherapy(EBRT) are effective treatments for prostate cancer(PC) but cause genitourinary(GU) and gastrointestinal(GI) toxicities. There is no consensus on the timing of HDR-BT in relation to EBRT and the effect of sequencing on patients. ObjectiveThe primary objective was to assess differences, if any, in the incidence of Grade 3 or higher GU toxicities from treatment. We also aimed to explore the incidence of G1-4 GI toxicities, quality of life and patient satisfaction. Suppression of PSA and signals for survival differences were also analysed. MethodologyA single-centre randomised trial in intermediate and high-risk localised PC patients to receive HDR-BT before (Arm A) or after (Arm B) EBRT. Toxicities were graded using CTCAE. IIEF and FACT-P were used to assess erectile dysfunction and QOL at 0, 3, 9 and 12 months. Results50 patients were recruited to each arm, with 48 and 46 patients completing treatment and follow up in each arm. 81.5% had high-risk disease. There were no G3 or G4 GU or GI toxicities. G1 urinary frequency was the most common adverse event experienced in both arms, peaking in incidence 3 months after commencing treatment (45.7 and 42.2% in Arm A and B, respectively). Up to 11 % of patients reported G1 urinary frequency at 12 months. Other G1 GU toxicities experienced by >10% of patients were urinary tract obstruction, tract pain and urgency. These symptoms also peaked in incidence at 3 months. G2 GU toxicities were uncommon and experienced in a maximum of 2 patients within each arm at any time point.Over 30% of patients had G1 flatulence at baseline and this remained the most frequently occurring G1 GI toxicity throughout the study, peaking at 12months (21.4% and 25.6% in Arm A and Arm B, respectively). Other GI toxicities experienced by more than 10% of patients were GI pain, proctitis and rectal mucositis, most of which demonstrated a peak incidence at 3 or 9 months. G2 GI toxicities were uncommon, except G2 flatulence.No significant difference was found in CTCAE, IPSS, IIEF, FACT-P and QOL scores between the arms.Median PSA follow-up was 5 years. 7 patients had treatment failure in each arm. DFRS was 93.3% and 90.7% at 5 years in Arm A and B respectively, with median failure time of 60 and 48 months in Arm A and B respectively. There were no statistically significant difference between arms. ConclusionsThe sequencing of HDR-BT and EBRT did not impact the incidence of G3 or G4 toxicities and no significant differences were seen in other patient reported outcomes. Treatment was well tolerated with maintained QOL scores. Treatment failure was low in both arms in a high-risk cohort, however a larger study with longer follow up is underway to establish whether the difference in median time to failure between the two arms is a signal of superiority.

Assessing the Value of CT in the Staging and Management of High-risk Prostate Cancer Patients

Assessing the Value of CT in the Staging and Management of High-risk Prostate Cancer Patients

Prediction of clinically significant prostate cancer by [68Ga]Ga-PSMA-11 PET/CT: a potential tool for selecting patients for active surveillance.

In our study, our aim was to investigate the role of [68Ga]Ga-PSMA-11 PET /CT imaging in the diagnosis of clinically significant prostate cancer (csPCa) (ISUP GG 2 and higher) in patients initially diagnosed with ISUP GG 1 and 2 after prostate biopsy. We retrospectively reviewed 147 patient records in whom [68Ga]Ga-PSMA-11 PET/CT imaging was performed preoperatively. All patients were initially diagnosed with ISUP GG 1 and 2 PCa by biopsy. Final pathology reports were obtained after radical prostatectomy. The [68Ga]Ga-PSMA-11 PET/CT images were evaluated to determine the PRIMARY score. Patients' mpMRI-PIRADS scores were also recorded when available and analyzed in correlation with the pathology results. For the 114 patients scored using PRIMARY, 19 out of 37 patients with scores of 1 and 2 (51%) were diagnosed with csPCa. Of the 77 patients with PRIMARY scores between 3 and 5, 64 (83%) had csPCa. Notably, every patient with a PRIMARY score of 5 had csPCa. PRIMARY scoring had a sensitivity of 77% and specificity of 58%, with a positive predictive value of 83%. A moderate correlation was observed between PRIMARY scores and ISUP GG (Rho = 0.54, p < 0.001). In contrast, the PIRADS score displayed a sensitivity and specificity of 86% and 25% respectively, with a positive predictive value of 68%. No substantial correlation was found between PIRADS and ISUP GG. Statistical analysis revealed a significant correlation between PRIMARY and ISUP GG (p < 0.001), but not between PIRADS and ISUP GG (p = 0.281). Comparatively, PRIMARY scoring was significantly more reliable than PIRADS scoring in identifying csPCa. [68Ga]Ga-PSMA-11 PET/CT imaging is promising for distinguishing high-risk prostate cancer patients from those apt for active surveillance, potentially aiding in the identification of csPCa.

Prostate cancer invading rectal serosa and anal sphincter treated with definitive radiation therapy: Case report and review of the literature

ABSTRACT Despite anatomical proximity, prostatic adenocarcinoma with rectal invasion is rare. We describe a case of prostate cancer invading the anal sphincter, treated with radiation therapy (RT). A 78-year-old patient underwent definitive radiotherapy in 2018 because of poorly differentiated adenocarcinoma, Gleason 4 + 3 (7). The initial stage was mrT4N0 on magnetic resonance imaging (MRI) images. The pre-treatment prostate-specific antigen level was 142 ng/mL, and the patient was subjected to androgen deprivation therapy. RT was performed using volumetric modulated arc therapy (VMAT) and a dose of 76 Gy in 38 fractions. After 2 months, MRI showed a complete response. During RT, toxicity was limited to mild gastro-intestinal and urologic symptoms. This report is the first to describe prostate cancer invasion of the anal sphincter and to extend to that condition the use of RT – already regarded as a useful treatment option for inoperable locally advanced high-risk prostate cancer (PC). This study suggests that VMAT can be a safe and effective treatment option for locally advanced high-risk PC patients.

Computed Tomography-Based Radiomics for Long-Term Prognostication of High-Risk Localized Prostate Cancer Patients Received Whole Pelvic Radiotherapy.

Given the high death rate caused by high-risk prostate cancer (PCa) (>40%) and the reliability issues associated with traditional prognostic markers, the purpose of this study is to investigate planning computed tomography (pCT)-based radiomics for the long-term prognostication of high-risk localized PCa patients who received whole pelvic radiotherapy (WPRT). This is a retrospective study with methods based on best practice procedures for radiomics research. Sixty-four patients were selected and randomly assigned to training (n = 45) and testing (n = 19) cohorts for radiomics model development with five major steps: pCT image acquisition using a Philips Big Bore CT simulator; multiple manual segmentations of clinical target volume for the prostate (CTVprostate) on the pCT images; feature extraction from the CTVprostate using PyRadiomics; feature selection for overfitting avoidance; and model development with three-fold cross-validation. The radiomics model and signature performances were evaluated based on the area under the receiver operating characteristic curve (AUC) as well as accuracy, sensitivity and specificity. This study's results show that our pCT-based radiomics model was able to predict the six-year progression-free survival of the high-risk localized PCa patients who received the WPRT with highly consistent performances (mean AUC: 0.76 (training) and 0.71 (testing)). These are comparable to findings of other similar studies including those using magnetic resonance imaging (MRI)-based radiomics. The accuracy, sensitivity and specificity of our radiomics signature that consisted of two texture features were 0.778, 0.833 and 0.556 (training) and 0.842, 0.867 and 0.750 (testing), respectively. Since CT is more readily available than MRI and is the standard-of-care modality for PCa WPRT planning, pCT-based radiomics could be used as a routine non-invasive approach to the prognostic prediction of WPRT treatment outcomes in high-risk localized PCa.