Focal therapy for localized prostate cancer in the era of routine multi-parametric MRI

Surveillance after Focal Therapy - a Comprehensive Review

BACKGROUND

to date, no standardized, evidence-based follow-up schemes exist for the monitoring of patients who underwent focal therapy (FT) and expert centers rely mainly on their own experience and/or institutional protocols. We aimed to perform a comprehensive review of the most advantageous follow-up strategies and their rationale after FT for prostate cancer (PCa).

METHODS

a narrative review of the literature was conducted to investigate different follow-up protocols of FT for PCa. Outcomes of interest were post-ablation oncological and functional outcomes and complications.

RESULTS

Oncological success after FT was generally defined as the biopsy-confirmed absence of clinically significant PCa in the treated zone. De novo PCa in the untreated area usually reflects an inaccurate patient selection and should be treated as primary PCa. During follow-up, oncological outcomes should be evaluated with periodic PSA, multiparametric MRI and prostate biopsy. The use of PSA derivatives and new biomarkers is still controversial and therefore not recommended. The first MRI after FT should be performed between 6-12 months to avoid ablation-related artifacts and diagnostic delay in case of FT failure. Other imaging modalities, such as PSMA PET/CT scan, are promising but still need to be validated in the post-FT setting. A 12-month "for-protocol" prostate biopsy, including targeted and systematic biopsy, was generally considered the preferred biopsy method to rule out tumor persistence/recurrence. Subsequent mpMRIs and biopsies should follow a risk-adapted approach depending on the clinical scenario. Functional outcomes should be periodically assessed using validated questionnaires within the first year, when typically recover to a new baseline. Complications, despite uncommon, should be strictly monitored mainly in the first month.

CONCLUSIONS

FT follow-up is a multifaceted process involving clinical, radiological, and histological assessment. Studies evaluating the impact of different follow-up strategies and ideal timings are needed to produce standardized protocols following FT.

Clinical efficacy of prostate PI-RADS V2.1 score combined with serum PSA-related indicators in the detection of gray zone prostate cancer

PURPOSE

The purpose of this study is to improve the diagnostic accuracy of gray zone prostate cancer evaluation by combining the prostate imaging report and data system version 2.1 (PI-RADS V2.1) score with serum prostate-specific antigen (PSA).

METHODS

We analyzed data from 212 men suspected of having prostate cancer and compared PSA-related indicators and PI-RADS V2.1 scores between 96 patients with prostate cancer and 116 without prostate cancer. By contrasting PI-RADS V2.1 scores with serum PSA-related markers, the diagnostic precision in the detection of grey zone prostate cancer was assessed.

RESULTS

The median PI-RADS V2.1 scores and serum tPSA levels of patients with prostate cancer were significantly higher (P < 0.05). The PI-RADS V2.1 score correlated positively with serum tPSA, PSA density (PSAD), and prostate health index (PHI) levels (P < 0.05) and negatively correlated with fPSA/tPSA concentrations (P < 0.05). Logistic regression identified risk factors including family history, PI-RADS V2.1 score, tPSA, PSAD, and PHI, with prostate volume and fPSA/tPSA as protective factors (P < 0.05). Combining serum PSA-related indicators with the PI-RADS V2.1 score improved diagnostic accuracy for gray zone prostate cancer (AUC 0.986, specificity 99.14%, sensitivity 92.71%).

CONCLUSION

The presence of a family history, a high PI-RADS V2.1 score, and elevated serum PSA-related markers contribute to high prostate cancer risk and development. The combined use of these indicators offers superior predictive value in detecting prostate cancer compared to a single indicator.

Real-Time and Delayed Imaging of Tissue and Effects of Prostate Tissue Ablation

PURPOSE OF REVIEW

Prostate ablation is increasingly being utilized for the management of localized prostate cancer. There are several energy modalities with varying mechanism of actions which are currently used for prostate ablation. Prostate ablations, whether focal or whole gland, are performed under ultrasound and/or MRI guidance for appropriate treatment plan execution and monitoring. A familiarity with different intraoperative imaging findings and expected tissue response to these ablative modalities is paramount. In this review, we discuss the intraoperative, early, and delayed imaging findings in prostate from the effects of prostate ablation.

RECENT FINDINGS

The monitoring of ablation both during and after the therapy became increasingly important due to the precise targeting of the target tissue. Recent findings suggest that real-time imaging techniques such as MRI or ultrasound can provide anatomical and functional information, allowing for precise ablation of the targeted tissue and increasing the effectiveness and precision of prostate cancer treatment. While intraprocedural imaging findings are variable, the follow-up imaging demonstrates similar findings across various energy modalities. MRI and ultrasound are two of the frequently used imaging techniques for intraoperative monitoring and temperature mapping of important surrounding structures. Follow-up imaging can provide valuable information about ablated tissue, including the success of the ablation, presence of residual cancer or recurrence after the ablation. It is critical and helpful to understand the imaging findings during the procedure and at different follow-up time periods to evaluate the procedure and its outcome.

Application of targeted diagnosis of PSMA in the modality shift of prostate cancer diagnosis: a review

Prostate cancer (PCa) is a serious threat to the health of men all over the world. The progression of PCa varies greatly among different individuals. In clinical practice, some patients often progress to advanced PCa. Therefore, accurate imaging for diagnosis and staging of PCa is particularly important for clinical management of patients. Conventional imaging examinations such as MRI and CT cannot accurately diagnose the pathological stages of advanced PCa, especially metastatic lymph node (LN) stages. As a result, developing an accurate molecular targeted diagnosis is crucial for advanced PCa. Prostate specific membrane antigen (PSMA) is of great value in the diagnosis of PCa because of its specific expression in PCa. At present, researchers have developed positron emission tomography (PET) targeting PSMA. A large number of studies have confirmed that it not only has a higher tumor detection rate, but also has a higher diagnostic efficacy in the pathological stage of advanced PCa compared with traditional imaging methods. This review summarizes recent studies on PSMA targeted PET in PCa diagnosis, analyzes its value in PCa diagnosis in detail, and provides new ideas for urological clinicians in PCa diagnosis and clinical management.

Prediction and Mapping of Intraprostatic Tumor Extent with Artificial Intelligence

Background

Magnetic resonance imaging (MRI) underestimation of prostate cancer extent complicates the definition of focal treatment margins.

Objective

To validate focal treatment margins produced by an artificial intelligence (AI) model.

Design setting and participants

Testing was conducted retrospectively in an independent dataset of 50 consecutive patients who had radical prostatectomy for intermediate-risk cancer. An AI deep learning model incorporated multimodal imaging and biopsy data to produce three-dimensional cancer estimation maps and margins. AI margins were compared with conventional MRI regions of interest (ROIs), 10-mm margins around ROIs, and hemigland margins. The AI model also furnished predictions of negative surgical margin probability, which were assessed for accuracy.

Outcome measurements and statistical analysis

Comparing AI with conventional margins, sensitivity was evaluated using Wilcoxon signed-rank tests and negative margin rates using chi-square tests. Predicted versus observed negative margin probability was assessed using linear regression. Clinically significant prostate cancer (International Society of Urological Pathology grade ≥2) delineated on whole-mount histopathology served as ground truth.

Results and limitations

The mean sensitivity for cancer-bearing voxels was higher for AI margins (97%) than for conventional ROIs (37%, p < 0.001), 10-mm ROI margins (93%, p = 0.24), and hemigland margins (94%, p < 0.001). For index lesions, AI margins were more often negative (90%) than conventional ROIs (0%, p < 0.001), 10-mm ROI margins (82%, p = 0.24), and hemigland margins (66%, p = 0.004). Predicted and observed negative margin probabilities were strongly correlated (R2 = 0.98, median error = 4%). Limitations include a validation dataset derived from a single institution's prostatectomy population.

Conclusions

The AI model was accurate and effective in an independent test set. This approach could improve and standardize treatment margin definition, potentially reducing cancer recurrence rates. Furthermore, an accurate assessment of negative margin probability could facilitate informed decision-making for patients and physicians.

Patient summary

Artificial intelligence was used to predict the extent of tumors in surgically removed prostate specimens. It predicted tumor margins more accurately than conventional methods.

Landmarks in the evolution of prostate biopsy

Approaches and techniques used for diagnostic prostate biopsy have undergone considerable evolution over the past few decades: from the original finger-guided techniques to the latest MRI-directed strategies, from aspiration cytology to tissue core sampling, and from transrectal to transperineal approaches. In particular, increased adoption of transperineal biopsy approaches have led to reduced infectious complications and improved antibiotic stewardship. Furthermore, as image fusion has become integral, these novel techniques could be incorporated into prostate biopsy methods in the future, enabling 3D-ultrasonography fusion reconstruction, molecular targeting based on PET imaging and autonomous robotic-assisted biopsy.

Safety and Feasibility of Transperineal Targeted Microwave Ablation for Low- to Intermediate-risk Prostate Cancer

Background

Focal therapy has emerged as an interesting option for localized low- to intermediate-risk prostate cancer (PCa). Targeted microwave ablation (TMA) is a novel FT modality involving targeted delivery of microwave energy under multiparametric magnetic resonance imaging (MRI)/ultrasound guidance.

Objective

To describe the step-by-step procedure for TMA and report early functional outcomes.

Design, setting, and participants

This was an experimental phase 1–2 trial in 11 patients diagnosed with a single, MRI-visible PCa lesion of up to 12 mm, scored as International Society of Urological Pathology grade group (GG) 1 or 2.

Surgical procedure

Transperineal TMA under MRI/ultrasound image fusion guidance.

Measurements

We recorded patient and PCa features; intraoperative and postoperative parameters; pain (Visual Analog Scale [VAS]) and adverse events (Common Terminology Criteria for Adverse Events v5.0); and prostate-specific antigen (PSA), International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF-5) scores at 1 wk and 1, 3, and 6 mo.

Results and limitations

The median patient age was 67 yr (interquartile range [IQR] 18). Median PSA was 5.4 ng/ml (IQR 1.8), median prostate volume was 51 cm³ (IQR 35), and median lesion size on MRI was 10 mm (IQR 4). Ten patients had GG 2 PCa and one had GG 1 disease. The median procedure time was 40 min (IQR 30). No intraoperative complications were reported. All treatments were performed on a day-case basis and no patients were discharged with a urinary catheter. Postoperatively, no grade ≥2 complications were reported. No significant changes in PSA (p = 0.46), IPSS (p = 0.39), or IIEF-5 scores (p = 0.18) scores were reported. The postoperative VAS score at 24 h was 0 for all patients.

Conclusions

TMA is safe, feasible, and well tolerated in patients with low- to intermediate-risk PCa. Oncological outcomes are still awaited.

Patient summary

Targeted microwave therapy is safe and feasible for selected patients with low- to intermediate-risk prostate cancer. The procedure is well tolerated and does not require a urinary catheter after the procedure. Cancer control outcomes are still awaited.

mpMRI-US Fusion-Guided Targeted Cryotherapy in Patients with Primary Localized Prostate Cancer: A Prospective Analysis of Oncological and Functional Outcomes

Simple Summary

Targeted cryotherapy is an emerging treatment for prostate cancer (PCa). mpMRI is a powerful tool for image fusion techniques that deliver incremental precision in diagnostic and treatment of PCa. Fusion targeted cryotherapy (FTC) arises from the simultaneous application of both these procedures. Recurrence is a concern after any type of PCa treatment, especially after targeted treatments. In this article we investigate the recurrence rate after FTC and the role of Prostate-Specific Antigen (PSA) as a predictor of recurrences. Our research provides new evidence on the feasibility of FCT by providing new insights on patient management.

Abstract

Targeted therapy (TT) for prostate cancer (PCa) aims to ablate the malignant lesion with an adequate margin of safety in order to obtain similar oncological outcomes, but with less toxicity than radical treatments. The main aim of this study was to evaluate the recurrence rate (RR) in patients with primary localized PCa undergoing mpMRI/US fusion targeted cryotherapy (FTC). A secondary objective was to evaluate prostate-specific antigen (PSA) as a predictor of recurrences. We designed a prospective single-center single-cohort study. Patients with primary localized PCa, mono or multifocal lesions, PSA ≤ 15 ng/mL, and a Gleason score (GS) ≤ 4 + 3 undergoing FTC were enrolled. RR was chosen as the primary outcome. Recurrence was defined as the presence of clinically significant prostate cancer in the treated areas. PSA values measured at different times were tested as predictors of recurrence. Continuous variables were assessed with the Bayesian t-test and categorical assessments with the chix-squared test. Univariate and logistic regression assessment were used for predictions. A total of 75 cases were included in the study. Ten subjects developed a recurrence (RR: 15.2%), while fifty-six (84.8%) patients showed a recurrence-free status. A %PSA drop of 31.5% during the first 12 months after treatment predicted a recurrence with a sensitivity of 53.8% and a specificity of 79.2%. A PSA drop of 55.3% 12 months after treatment predicted a recurrence with a sensitivity of 91.7% and a specificity of 51.9%. FTC for primary localized PCa seems to be associated with a low but not negligible percentage of recurrences. Serum PSA levels may have a role indicating RR.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

Association of prostate zonal volume with location and aggressiveness of clinically significant prostate cancer: A multiparametric MRI study according to PI-RADS version 2.1

BACKGROUND

The relationship between prostate cancer (PCa) and benign prostatic hyperplasia (BPH) remains unclear. This study aimed to determine whether prostate zonal volume was associated with the location and aggressiveness of PCa.

METHODS

412 PCa patients were retrospectively enrolled. The volumes of the whole prostate (V) and transition zone (Vtz) were calculated by the prolate ellipsoid formula, and volume of the peripheral zone (Vpz) was calculated by their subtraction. Locations of PCa were divided into three categories, including peripheral zone (PZ), transition zone (Vtz) and mixed zone group. The mixed zone group was further divided into PZ-dominated, TZ-dominated and equally distributed subgroups.

RESULTS

The Vtz of Gleason score (GS) 3 + 4 group was the largest, while the Vpz of GS 9 group was the largest. Tumor diameters of the PZ and TZ groups were weakly correlated with their corresponding zonal volume (r = 0.261, p < 0.001; r = 0.311, p = 0.009, respectively). There was no significant difference in the zonal volumes and GS distribution among the location groups. The proportion of tumors with high-grade GS of 8 and 9 was higher in the PZ than that in the TZ group (38.5 vs 24.3%, p = 0.041). For tumors located in the TZ, the V and Vpz of tumors with high-grade GS were larger than those in the low-grade GS of 7 group (p = 0.033 and 0.039, respectively). Among the subgroups of mixed zone group, the Vtz of the TZ-dominated group was larger than those of PZ-dominated and equally distributed groups (p = 0.016 and 0.001, respectively).

CONCLUSION

PCa with high-grade GS is more likely to have a relatively larger Vpz and involve PZ, while PCa with a larger Vtz is more likely to be with low-grade GS, which support the theoretical model that pressure exerted by increasing prostate size/mechanical deformation may inhibit PCa growth from the clinical point. However, the increase in zonal volume might not be the direct cause of tumorigenesis and aggressiveness.

First experiences and results after cryoablation of prostate cancer with histopathological evaluation and imaging-based follow-up

Aim: To share our experience after 28 cryoablation treatments for prostate cancer (PCa) with histopathology, clinical data and MRI as the follow-up methods. Methods: Clinical follow-up comprised prostate specific antigen (PSA)-measurements, PSA-density and quality-of-life-parameters. multi-parametric (mp)MRI pre- and post-cryoablation were retrospectively re-analyzed in 23 cases using Likert scores. Follow-up-histopathology was performed via MRI/ultrasound fusion-guided and/or systematic biopsy. Receiver operating characteristic curve analysis was performed. Results: 17 PCa (61%) were diagnosed within 12-month post-cryotherapy (infield and out-of-field disease). PSA levels and PSA density were not significantly different between patients with or without PCa recurrence. mpMRI can characterize the decrease in prostate volume and necrosis. Area under the curve for the detection of PCa was 81% (global Likert scores), 74-87% (T2), 78% (diffusion weighted imaging) and 57-78% (dynamic contrast enhanced imaging; Youden-selected cutoff ≥3). Conclusion: Besides histopathological evaluation and control biopsy, MRI might have the potential to accurately detect PCa after cryotherapy. Clinical data and interdisciplinary communication are required for efficient monitoring after cryoablation treatments for PCa.

High-Intensity Focused-Ultrasound Focal Therapy Versus Laparoscopic Radical Prostatectomy: A Comparison of Oncological and Functional Outcomes in Low- and Intermediate-Risk Prostate Cancer Patients

To compare oncological and functional outcomes of high-intensity focused-ultrasound (HIFU) focal therapy (FT) versus laparoscopic radical prostatectomy (LRP) in patients treated for low- or intermediate-risk prostate cancer (PCa), we retrospectively analyzed data of consecutive patients comprising 30 men, who underwent HIFU-FT, and 96 men who underwent LRP, in an academic center. Oncological outcomes were assessed based on the follow-up prostate-specific antigen values. We used the International Index of Erectile Function short form score to assess erectile function (EF). Urinary continence status was defined based on the number of pads used per day. Median follow-up was 12.5 and 19.1 months in the LRP and HIFU-FT groups, respectively. The effects were computed after propensity score matching and expressed as average treatment effect (ATE). Compared to LRP, HIFU-FT was associated with increased risk of treatment failure (ATE 0.103–0.164, depending on definition, p < 0.01) and lower risk of urinary incontinence (ATE −0.808 at 12 months, p < 0.01). Risk of erectile dysfunction was higher in the LRP group (ATE 5.092, p < 0.01). Our results demonstrate that HIFU-FT may be a reasonable treatment option in selected PCa patients, willing to preserve their EF and urinary continence yet accepting a higher risk of treatment failure.

Machine Learning in Prostate MRI for Prostate Cancer: Current Status and Future Opportunities

Advances in our understanding of the role of magnetic resonance imaging (MRI) for the detection of prostate cancer have enabled its integration into clinical routines in the past two decades. The Prostate Imaging Reporting and Data System (PI-RADS) is an established imaging-based scoring system that scores the probability of clinically significant prostate cancer on MRI to guide management. Image fusion technology allows one to combine the superior soft tissue contrast resolution of MRI, with real-time anatomical depiction using ultrasound or computed tomography. This allows the accurate mapping of prostate cancer for targeted biopsy and treatment. Machine learning provides vast opportunities for automated organ and lesion depiction that could increase the reproducibility of PI-RADS categorisation, and improve co-registration across imaging modalities to enhance diagnostic and treatment methods that can then be individualised based on clinical risk of malignancy. In this article, we provide a comprehensive and contemporary review of advancements, and share insights into new opportunities in this field.

Oncological and functional outcome after partial prostate HIFU ablation with Focal-One®: a prospective single-center study

BACKGROUND

We aimed to evaluate oncological and functional outcomes of index lesion HIFU ablation with Focal-One^®.

MATERIALS AND METHODS

We prospectively assessed treatment-naïve men with localized prostate cancer between 2017 and 2019. Inclusion criteria were stage cT ≤ 2, ≥5 years of life expectancy, grade group ≤3. Multiparametric magnetic resonance was performed before ablation. Patients with a prostate volume of ≥80 ml underwent debulking. Treatment failure was defined as a histologically confirmed tumor that required salvage treatment or androgen deprivation therapy.

RESULTS

One hundred and eighty nine patients were enrolled. Data are presented as median and Interquartile Range (IQR). Median age was 70(11) years. Median baseline PSA was 5.8(3) ng/ml. Fourteen (7.4%) patients had prostate debulking before ablation. 104 (55%) patients underwent targeted ablation, 45 (23.8%) extended targeted ablation, 31 (16.4%) hemiablation, and 9 (4.8%) extended hemiablation. Median targeted ablated volume was 14(9) ml. Ninety-three complications occurred in 63/189 (33.3%) patients within 90 days. There were 77/93 (82.8%) minor (Clavien grade 1-2) and 16/93 (17.2%) major complications (Clavien grade 3a). Thirty-nine patients suffered from genito-urinary infections (Clavien grade 2). Fifteen patients required transurethral resection of the prostate/urethrotomy for recurrent urinary retention (Clavien grade 3a). One patient developed a recto-urethral fistula (Clavien grade 3a) and two long-lasting urinary incontinence. Median PSA nadir was 2.2(2.9) ng/ml. At a median follow-up of 29(15) months, 21/177 (11.9%) patients were treatment failures, 26 on monitoring, and 26 had a further ablation. Multivariable logistic regression found that failure patients had higher PSA (7.8 vs 5.7 ng/ml,p0.001) and double PSA nadir (4.8 vs 2.0 ng/ml, p < 0.001). Higher PSA nadir correlated with a 74% higher probability of failure (OR 1.74 95% CI 1.40-2.16). Cancer in the anterior stroma increased the odds of failure of three folds (OR 3.36 95% CI 1.18-9.53). Two mixed effect models (one for IPSS and one for IEEF-15) were estimated and they showed that time reaches the statistical significance coefficient only for the IEEF-15, meaning that subsequent evaluations of the indicators were significantly lower at each time point.

CONCLUSIONS

Index lesion HIFU ablation demonstrated satisfactory early oncological outcome but anteriorly located tumors had inadequate ablation. Urinary function was well preserved. Sexual function slightly decreased during follow-up.

An anthropomorphic pelvis phantom for MR-guided prostate interventions

PURPOSE

To design and manufacture a pelvis phantom for magnetic resonance (MR)-guided prostate interventions, such as MRGB (MR-guided biopsy) or brachytherapy seed placement.

METHODS

The phantom was designed to mimic the human pelvis incorporating bones, bladder, prostate with four lesions, urethra, arteries, veins, and six lymph nodes embedded in ballistic gelatin. A hollow rectum enables transrectal access to the prostate. To demonstrate the feasibility of the phantom for minimal invasive MRI-guided interventions, a targeted inbore MRGB was performed. The needle probe was rectally inserted and guided using an MRI-compatible remote controlled manipulator (RCM).

RESULTS

The presented pelvis phantom has realistic imaging properties for MR imaging (MRI), computed tomography (CT) and ultrasound (US). In the targeted inbore MRGB, a prostate lesion was successfully hit with an accuracy of 3.5 mm. The experiment demonstrates that the limited size of the rectum represents a realistic impairment for needle placements.

CONCLUSION

The phantom provides a valuable platform for evaluating the performance of MRGB systems. Interventionalists can use the phantom to learn how to deal with challenging situations, without risking harm to patients.

Focal therapy for primary and salvage prostate cancer treatment: a narrative review

Despite innovations in surgical technology and advancements in radiation therapy, radical treatments for clinically localized prostate cancer are associated with significant patient morbidity, including both urinary and sexual dysfunction. This has created a vital need for therapies and management strategies that provide an acceptable degree of oncologic efficacy while mitigating these undesirable side effects. Successful developments in screening approaches and advances in prostate imaging have allowed clinicians to identify, localize, and more precisely target early cancers. This has afforded urologists with an important opportunity to develop and employ focal ablation techniques that selectively destroy tumors while preserving the remainder of the gland, thus avoiding detrimental treatment effects to surrounding sensitive structures. A lack of high-level evidence supporting such an approach had previously hindered widespread adoption of focal treatments, but there are now numerous published clinical trials which have sought to establish benchmarks for safety and efficacy. As the clinical evidence supporting a potential role in prostate cancer treatment begins to accumulate, there has been a growing acceptance of focal therapy in the urologic oncology community. In this narrative review article, we describe the techniques, advantages, and side effect profiles of the most commonly utilized focal ablative techniques and analyze published clinical trial data supporting their evolving role in the prostate cancer treatment paradigm.

Dual-Functional PLGA Nanoparticles Co-Loaded with Indocyanine Green and Resiquimod for Prostate Cancer Treatment

PURPOSE

With the advance of screening techniques, there is a growing number of low-risk or intermediate-risk prostate cancer (PCa) cases, remaining a serious threat to men's health. To obtain better efficacy, a growing interest has been attracted to develop such emerging treatments as immunotherapy and focal therapy. However, few studies offer guidance on whether and how to combine these modalities against PCa. This study was designed to develop dual-functional nanoparticles (NPs) which combined photothermal therapy (PTT) with immunotherapy and determine the anti-tumor efficacy for PCa treatment.

METHODS

By a double emulsion technique, the drug nanocarrier, poly(lactic-co-glycolic acid) or PLGA, was applied for co-loading of a fluorescent dye, indocyanine green (ICG) and a toll-like receptor 7/8 (TLR7/8) agonist resiquimod (R848) to synthesize PLGA-ICG-R848 NPs. Next, we determined their characteristic features and evaluated whether they inhibited the cell viability in multiple PCa cell lines. After treatment with PLGA-ICG-R848, the maturation markers of bone marrow-derived dendritic cells (BMDCs) were detected by flow cytometry. By establishing a subcutaneous xenograft model of mouse PCa, we explored both the anti-tumor effect and immune response following the NPs-based laser ablation.

RESULTS

With a mean diameter of 157.7 nm, PLGA-ICG-R848 exhibited no cytotoxic effect in PCa cells, but they significantly decreased RM9 cell viability to (3.9±1.0)% after laser irradiation. Moreover, PLGA-ICG-R848 promoted BMDCs maturation with the significantly elevated proportions of CD11c+CD86+ and CD11c+CD80+ cells. Following PLGA-ICG-R848-based laser ablation in vivo, the decreased bioluminescent signals indicated a significant inhibition of PCa growth, while the ratio of splenic natural killer (NK) cells in PLGA-ICG-R848 was (3.96±1.88)% compared with (0.99±0.10)% in PBS group, revealing the enhanced immune response against PCa.

CONCLUSION

The dual-functional PLGA-ICG-R848 NPs under laser irradiation exhibit the anti-tumor efficacy for PCa treatment by combining PTT with immunotherapy.

MR-Guided High-Intensity Directional Ultrasound Ablation of Prostate Cancer

PURPOSE OF REVIEW

The goal of this paper was to review the novel treatment modality of high-intensity transurethral directional ultrasound for prostate cancer.

RECENT FINDINGS

Prostate cancer is a heterogeneous disease with some patients electing for active surveillance and focal therapies instead of definitive treatment with radical prostatectomy or radiation therapy. Prostate MRI has become a cornerstone of prostate cancer diagnosis, targeted biopsy, and treatment planning. Transurethral high-intensity directional ultrasound allows for MRI-guided ablation of the prostate gland with the ability to contour boundaries and spare critical structures, such as the neurovascular bundle and urinary sphincter. Although results are still emerging, this may offer patients a new option for focal therapy with a favorable side-effect profile. High-intensity transurethral directional ultrasound is an emerging treatment modality for both whole-gland and focal ablation with promising early results. Further research is needed to establish safety, tolerability, and long-term oncologic outcomes.

Added Clinical Value of Whole-mount Histopathology of Radical Prostatectomy Specimens: A Collaborative Review

CONTEXT

Whole-mount histopathology, that is, large format histology or whole-mount sectioning, refers to the histopathological examination of tissue sections from specimens processed with large tissue cassette. In some institutions, it is applied routinely to specimens with genitourinary cancers.

OBJECTIVE

To give an overview of the application of the large format histology to the morphological examination of the radical prostatectomy (RP) specimens.

EVIDENCE ACQUISITION

A comprehensive PubMed search was performed up to May 2020, using the keywords "prostate carcinoma," "radical prostatectomy specimens," "whole-mount histopathology," "whole mount sectioning," "large format histology," "macrosectioning," "diagnostic criteria," and "prognosis." The search, supplemented with a hand search, was restricted to articles published in the English language. No limitations were placed on the publication year. References in relevant articles were also reviewed.

EVIDENCE SYNTHESIS

Even though the whole-mount sections of RPs appear not to be superior to regular sections in detecting adverse pathological features, their use has the advantage of displaying the architecture of the prostate gland and identifying and locating tumor nodule(s) more clearly, with particular reference to the index tumor. Further, it is easier to compare the pathological features with clinical findings derived, for instance, from digital rectal examination, transrectal ultrasound, multiparametric magnetic resonance imaging, surgical operation, and prostate biopsies.

CONCLUSIONS

Urologists, radiologists, and oncologists are updated about the step forward made by pathologists when diagnostic and prognostic information is derived from an approach that closely resembles that used by the clinicians when dealing with imaging findings.

PATIENT SUMMARY

Adoption of the whole-mount histopathology adds clinical value in correlation with clinical/imaging findings of radical prostatectomy specimens.

MAGE-C2/CT10 promotes growth and metastasis through upregulating c-Myc expression in prostate cancer

Prostate cancer (PC) is the most common reproductive cancer in men and the third leading cause of cancer death among men worldwide. Recently targeted therapy showed a significant therapeutic effect on PC, whereas finding more PC therapeutic target is still urgently needed. Melanoma-associated antigen-encoding C2 (MAGE-C2/CT10), which have significant homology with the MAGE-C1/CT-7 gene, was known to be involved in the development of a variety of tumors. However, the role and mechanism of MAGE-C2/CT10 in prostate cancer remains unclear. Herein, we found the high levels of MAGE-C2/CT10 in highly metastatic prostate cancer. Our findings confirmed that the depletion of MAGE-C2/CT10 suppressed the growth of PC cells, and restrained PC cell migration and invasion in vitro. We noticed MAGE-C2/CT10 could stimulate c-Myc expression via FBP1, and further contributed to PC cell proliferation and motility. Performing in vivo assays, we demonstrated MAGE-C2/CT10 promoted tumor growth and metastasis of PC cells in mice. Collectively, we found the abnormal expression of MAGE-C2/CT10 in PC, and revealed the regulatory mechanism underlying MAGE-C2/CT10 promoting PC progression and metastasis.