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Background: At present, it is not possible to predict the ablation zone volume following irreversible electroporation (IRE) for prostate cancer (PCa). This study aimed to determine the necessary electrical field threshold to ablate human prostate tissue in vivo with IRE. Methods: In this prospective multicenter trial, patients with localized PCa were treated with IRE 4 weeks before their scheduled radical prostatectomy. In 13 patients, numerical models of the electrical field were generated and compared with the ablation zone volume on whole-mount pathology and T2-weighted magnetic resonance imaging (MRI) sequences. Volume-generating software was used to calculate the ablation zone volumes on histology and MRI. The electric field threshold to ablate prostate tissue was determined for each patient. Results: A total of 13 patients were included for histological and simulation analysis. The median electrical field threshold was 550 V/cm (interquartile range 383-750 V/cm) for the software-generated histology volumes. The median electrical field threshold was 500 V/cm (interquartile range 386-580 V/cm) when the ablation zone volumes were used from the follow-up MRI. Conclusions: The electrical field threshold to ablate human prostate tissue in vivo was determined using whole-mount pathology and MRI. These thresholds may be used to develop treatment planning or monitoring software for IRE prostate ablation; however, further optimization of simulation methods are required to decrease the variance that was observed between patients.

Interesting developments took place in the treatment of prostate cancer including focal therapy for less aggressive organ-confined prostate cancer. Fortunately, curative treatment is often still an option for patients suffering from the lower staged tumors. In carefully selected patients, the prostate cancer may be focally treated followed by careful post-treatment evaluation, and if necessary by focal re-treatment. During the past decades, the age of men at prostate cancer detection has decreased by approximately ten years and men’s life expectancy has increased by almost four years. Together with the increased diagnosis of low- and intermediate risk prostate cancer, interest in the minimally invasive focal treatment with its lower side-effect profile has grown. The present thesis deliberates on a minimally invasive approach of treating prostate cancer within the concept of focal therapy. Focal therapy offers a middle ground between active surveillance and radical treatments as surgery or radiation therapy. Focal therapy is a minimally invasive treatment concept whereby active therapy is targeted to the malignant areas of the prostate gland while sparing the benign tissue and vital structures of the prostate aiming at better preservation of the quality of life. Additionally, this thesis provides the initial results of IRE research in prostate cancer that show the safety and feasibility of the procedure, quality of life, post-procedural imaging and histopathological outcomes after an IRE-procedure in the prostate.

Objective To define the role of multiparametric MRI (mpMRI) for treatment planning, guidance and follow-up in focal therapy for prostate cancer based on a multidisciplinary Delphi consensus project. Materials and Methods An online consensus process based on a questionnaire was circulated according to the Delphi method. Discussion points were identified by literature research and were sent to the panel via an online questionnaire in three rounds. A face-to-face consensus meeting followed the three rounds of questions that were sent to a 48-participant expert panel consisting of urologists, radiologists and engineers. Participants were presented with the results of the previous rounds. Conclusions formulated from the results of the questionnaire were discussed in the final face-to-face meeting. Results Consensus was reached in 41% of all key items. Patients selected for focal therapy should have biopsy-proven prostate cancer. Biopsies should ideally be performed after mpMRI of the prostate. Standardization of imaging protocols is essential and mpMRIs should be read by an experienced radiologist. In the follow-up after focal therapy, mpMRI should be performed after 6 months, followed by a yearly mpMRI. mpMRI findings should be confirmed by targeted biopsies before re-treatment. No consensus was reached on whether mpMRI could replace transperineal template saturation biopsies to exclude significant lesions outside the target lesion. Conclusions Consensus was reached on a number of areas related to the conduct, interpretation and reporting of mpMRI for use in treatment planning, guidance and follow-up of focal therapy for prostate cancer. Future studies, comparing mpMRI with transperineal saturation mapping biopsies, will confirm the importance of mpMRI for a variety of purposes in focal therapy for prostate cancer.

Background Focal Therapy (FT) for Prostate Cancer (PCa) is promising. However, long-term oncological results are awaited and there is no consensus on follow-up strategies. Molecular biomarkers (MB) may be useful in selecting, treating and following up men undergoing FT, though there is limited evidence in this field to guide practice. We aimed to conduct a consensus meeting, endorsed by the Focal Therapy Society, amongst a large group of experts, to understand the potential utility of MB in FT for localised PCa. Materials and methods A 38-item questionnaire was built following a literature search. The authors then performed three rounds of a Delphi Consensus using DelphiManager, using the GRADE grid scoring system, followed by a face-to-face expert meeting. Three areas of interest were identified and covered concerning MB for FT, i) the current/present role; ii) the potential/future role; iii) the recommended features for future studies. Consensus was defined using a 70% agreement threshold. Results Of 95 invited experts, 42 (44.2%) completed the three Delphi rounds. Twenty-four items reached a consensus and they were then approved at the meeting involving (n=15) experts. Fourteen items reached a consensus on uncertainty, or they did not reach a consensus. They were re-discussed, resulting in a consensus (n=3), a consensus on a partial agreement (n=1), and a consensus on uncertainty (n=10). A final list of statements were derived from the approved and discussed items, with the addition of three generated statements, to provide guidance regarding MB in the context of FT for localised PCa. Research efforts in this field should be considered a priority. Conclusions The present study detailed an initial consensus on the use of MB in FT for PCa. This is until evidence becomes available on the subject.

Background: At present, it is not possible to predict the ablation zone volume following irreversible electroporation (IRE) for prostate cancer (PCa). This study aimed to determine the necessary electrical field threshold to ablate human prostate tissue in vivo with IRE. Methods: In this prospective multicenter trial, patients with localized PCa were treated with IRE 4 weeks before their scheduled radical prostatectomy. In 13 patients, numerical models of the electrical field were generated and compared with the ablation zone volume on whole-mount pathology and T2-weighted magnetic resonance imaging (MRI) sequences. Volume-generating software was used to calculate the ablation zone volumes on histology and MRI. The electric field threshold to ablate prostate tissue was determined for each patient. Results: A total of 13 patients were included for histological and simulation analysis. The median electrical field threshold was 550 V/cm (interquartile range 383–750 V/cm) for the software-generated histology volumes. The median electrical field threshold was 500 V/cm (interquartile range 386–580 V/cm) when the ablation zone volumes were used from the follow-up MRI. Conclusions: The electrical field threshold to ablate human prostate tissue in vivo was determined using whole-mount pathology and MRI. These thresholds may be used to develop treatment planning or monitoring software for IRE prostate ablation; however, further optimization of simulation methods are required to decrease the variance that was observed between patients.

Annual Meeting of the Western-Section of the American-Urological-Association (AUA) -- AUG 06-10, 2017 -- Vancouver, CANADA WOS: 000444189400004 PubMed ID: 30211680 PURPOSE We aimed to evaluate the genitourinary function and quality of life (QoL) following the ablation of different prostate segments with irreversible electroporation (IRE) for localized prostate cancer (PCa). METHODS Sixty patients who received primary focal IRE for organ-confined PCa were recruited for this study. Patients were evaluated for genitourinary function and QoL per prostate segment treated (anterior vs. posterior, apex vs. base vs. apex-to-base, unilateral vs. bilateral). IRE system settings and patient characteristics were compared between patients with preserved vs. those with impaired erectile function and urinary continence. Data were prospectively collected at baseline, 3, 6, and 12 months using the expanded prostate cancer index composite, American Urological Association symptom score, SF-12 physical and mental component summary surveys. Difference over time within segments per questionnaire was evaluated using the Wilcoxon's signed rank test. Outcome differences between segments were assessed using covariance models. Baseline measurements included questionnaire scores, age, and prostate volume. RESULTS There were no statistically significant changes over time for overall urinary (P = 0.07-0.89), bowel (P = 0.06-0.79), physical (P = 0.18-0.71) and mental (P = 0.45-0.94) QoL scores within each segment. Deterioration of sexual function scores was observed at 6 months within each segment (P = 0.001-0.16). There were no statistically significant differences in QoL scores between prostate segments (P = 0.08-0.97). Older patients or those with poor baseline sexual function at time of treatment were associated with a greater risk of developing erectile dysfunction. CONCLUSION IRE is a feasible modality for all prostate segments without any significantly different effect on the QoL outcomes. Older patients and those with poor sexual function need to be counseled regarding the risk of erectile dysfunction. American Urological Association, Western Sect Australian Prostate Cancer Research Centre-NSW; St. Vincent's Prostate Cancer Centre The Australian Prostate Cancer Research Centre-NSW and the St. Vincent's Prostate Cancer Centre funded this research project.

Item does not contain fulltext INTRODUCTION: Salvage ablative therapy (SAT) has been developed as a form of localized treatment for localized recurrence of prostate cancers following radiation therapy. To better address the utility of SAT, prospective clinical trials must address the aspects of accepted standards in the initial evaluation, treatment, follow-up, and outcomes in the oncology community. We undertook this study to achieve consensus on uniform standardized trial design for SAT trials. METHODS: A literature search was performed and an international multidisciplinary group of experts was identified. A questionnaire was constructed and sent out to 71 participants in 3 consecutive rounds according to the Delphi method. The project was concluded with a face-to-face meeting in which the results were reviewed and conclusions were formulated. RESULTS: Patients with recurrent disease after radiation therapy were considered candidates for a SAT trial using any ablation scenario performed with cryotherapy or high-intensity focused ultrasound. It is feasible to compare different sources of energy or to compare with historical data on salvage radical prostatectomy outcomes. The primary objective should be to assess the efficacy of the treatment for negative biopsy rate at 12 months. Secondary objectives should include safety parameters and quality-of-life assessment. Exclusion criteria should include evidence of local or distant metastases. The optimal biopsy strategy is image-guided targeted biopsies. Follow-up includes multiparametric magnetic resonance imaging, prostate-specific antigen level, and quality of life for at least 5 years. CONCLUSIONS: A multidisciplinary board from international experts reached consensus on trial design for SAT in prostate cancer and provides a standard for designing a feasible SAT trial.