Focal therapy
Changing the landscape of prostate cancer treatments
Scheltema, M.J.V.
Publication date
2018
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Citation for published version (APA):
Scheltema, M. J. V. (2018). Focal therapy: Changing the landscape of prostate cancer
treatments.
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07
FEASIBILITY AND SAFETY OF FOCAL
IRREVERSIBLE ELECTROPORATION AS
SALVAGE TREATMENT FOR LOCALIZED
RADIO-RECURRENT PROSTATE CANCER
Scheltema MJ*, van den Bos W*, Siriwardana AR, Kalsbeek AM, Thompson JE, Ting F, Böhm M, Haynes AM, Shnier R, Delprado W, Stricker PD.
*contributed equally to the work
Published in the British Journal of Urology International 2017; epub ahead of print doi:10.1111/bju.13991
ABSTRACT
Objectives: To evaluate the feasibility, safety, early quality of life (QoL) and oncological
outcomes of salvage focal irreversible electroporation (IRE) for radio-recurrent prostate cancer (PCa).
Patients and methods: Patients with localized, radio-recurrent PCa without evidence
of metastatic or nodal disease were offered focal IRE following the consensus guidelines. Patients with a minimum follow-up of 6 months were eligible for analysis. Adverse events were monitored using the NCI Common Terminology Criteria for Adverse Events (CTCAE version 4.0). Patient-reported QoL data was collected at baseline, 6 weeks, 3, 6 and 12 months using the Expanded Prostate Cancer Index Composite (EPIC), AUA symptom score and SF-12 Physical and Mental Component Summary (SF12-physical/ SF12-mental) questionnaires. Oncological control was evaluated with serial prostate-specific antigen (PSA), 6-months multiparametric MRI (mpMRI) and 12-months prostate biopsy. Wilcoxon’s Signed Rank Test was used to assess QoL differences over time in paired continuous variables.
Results: A total of 18 patients were included for analysis. The median follow-up was 21
months. No high-grade adverse events (CTCAE >2) or recto-urethral fistula occurred. There were no statistically significant declines observed in QoL outcomes (n=11) on the EPIC Bowel domain (p=0.29), AUA symptom score (p=0.77), SF12-physical (p=0.17) and SF12-mental (p=0.77) questionnaires. At 6 months salvage patients experienced a decline in EPIC sexual domain (median of 38 to 24, p=0.028) and urinary domain (median of 96 to 92, p=0.074). Pad-free continence and erections sufficient for intercourse were preserved in 73% (n=8/11) and 33% (n=2/6) at 6 months, respectively. The mpMRI was clear in 85% (n=11/13), with two single out-field lesions (true-positive and false-positive, respectively). Median nadir PSA was 0.39 μg/L (IQR 0.04-0.43). A total of 3 (17%) and 4 (22%) patients experienced biochemical failure using the Phoenix and Stuttgart definitions of biochemical failure, respectively. 80% (n=8/10) of the patients were clear of any PCa on follow-up biopsy, whereas 2 patients had significant PCa on follow-up biopsy (ISUP 5).
Conclusion: Our short-term safety, QoL and oncological control data demonstrate that
focal IRE is a feasible salvage option for localized radio-recurrent PCa. A prospective multi-centre study (FIRE-trial) has been initiated that will provide further insight in the ability of focal IRE to obtain oncological control of radio-recurrent PCa with acceptable patient morbidity.
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INTRODUCTION
Up to one third of patients that undergo whole-gland radiotherapy (external-beam radiotherapy (EBRT), low- or high-dose rate brachytherapy (LDR/HDR)) as primary treatment for localized prostate cancer (PCa) experience radio-recurrent disease, with a high chance of developing clinically significant recurrent PCa.1–4 Current interventional
salvage treatment options include radical prostatectomy, brachytherapy, whole-gland cryosurgery or high-intensity focused ultrasound (HIFU).5 Surgical treatment of
radio-recurrent PCa is challenging with biochemical recurrence rates between 28% – 93%, post-intervention incontinence rates between 5.4% to 67%, erectile dysfunction from 23% to 100% and significant incidence of high-grade adverse events, e.g. recto-urethral fistula in 1% to 5.3%.6,7 A systematic review including 10 series on robotic radical
prostatectomy for radio-recurrent PCa showed that biochemical failure occurred in 29% (n=56/193), urinary continence was preserved in 60% (n=119/197) at mean follow-up of 18.6 months while the overall preserved potency rate was 26% in potent men (n=30/115).8 Therefore the majority of patients receive androgen deprivation therapy
(ADT) without curative intent.9,10
Focal ablative therapy has been evaluated for localized radio-recurrent PCa, aiming to reduce treatment-related toxicity while achieving local oncological control. In a recent systematic review on focal salvage therapy for radio-recurrent PCa, the 5-year biochemical disease-free survival was 46.5 – 54.5%.6 Feasibility trials have been
performed with HIFU, cryosurgery, iodine-125 brachytherapy and HDR.6,11 For
whole-gland salvage HIFU and cryosurgery biochemical failure occurred in 3% - 79% and rates of preserved urinary continence and potency range from 10% - 93% and 15% - 56%, respectively.7 For salvage brachytherapy biochemical-free survival was 34% - 88% with
grade 3-4 toxicity in 0% - 47%.7 Encouraging results regarding treatment-related toxicity
of focal HIFU were reported by Ahmed et al.12, however, other targeted focal therapy
trials reported higher rates of recto-urethral fistula (5.5%,13), treatment-induced erectile
dysfunction (50%,14) and incontinence (25%,15).
Irreversible electroporation is a novel focal therapy treatment which involves delivering high-voltage electrical pulses between needle electrodes.16 The obtained direct
electrical current destabilizes the targeted cellular membrane, inducing nanopores that cause irreversible permeability and subsequent cell death.16,17 Preclinical studies have
shown that the ablative effect of IRE harbours tissue-selectivity and is able to preserve blood vessel patency and spare nerves.18,19 The initial phase 1-2 trials with IRE for
localized, treatment-naïve PCa demonstrated the safety and feasibility of this technique, with limited treatment-related toxicity and good in-field oncological control.20–23 The
feasibility of this technique and the interesting fundamental process of IRE may help to reduce treatment-related toxicity with salvage therapy. However, no studies have been published on focal IRE for radio-recurrent PCa to date. We aimed to demonstrate the feasibility of focal salvage IRE for localized, radio-recurrent PCa by acquiring patient-reported QoL, adverse event and early oncological control data.
MATERIALS AND METHODS
Study design and patients
Institutional review board approval was obtained to perform salvage IRE procedures and to prospectively acquire QoL data (HREC approval SVH 13/018) and to retrospectively analyse collected oncological data (HREC approval SVH 16/110). Patients with localized, radio-recurrent PCa (any Gleason sum score ≥6) without evidence of nodal or metastatic disease were offered salvage IRE in a single-centre (St. Vincent’s Prostate Cancer Centre, Sydney/Australia) following the consensus guidelines on salvage ablative therapy (Table 1).24 Written informed consent was obtained from all patients. Only patients with
a minimum follow-up of 6 months were eligible for analysis. Adverse events, patient-reported QoL and oncological control data were analysed.
Table 1. Patient Criteria and Selection Methods
Patient Criteria Selection Methods
• Patients with unifocal, localized radio-recurrent PCa after LDR/PDR/ HDR brachytherapy or External Beam Radiation Therapy
• Any Gleason Score/ISUP 1-5
• Any number of positive cores/core involvement • No evidence of metastatic or nodal disease
• If applicable, stop androgen deprivation therapy before treatment
• Transrectal or transperineal saturation biopsies Baseline imaging to exclude evidence of local or distant metastases • MRI-targeted biopsies if a
lesion is seen
Cancer localization
Extensive systematic prostate biopsies were used to detect localized, radio-recurrent PCa and used for treatment planning (median of 22 cores). Transperineal template-guided mapping biopsies (TTMB) were performed in 95% (n=17/18), whereas one patient received transrectal ultrasound (TRUS)-guided template biopsies (n=1, 21 cores) (see Table 2 for specifications). Multiparametric prostate MRI (mpMRI) was used to guide prostate biopsies. The mpMRIs were obtained and interpreted following the Prostate Imaging Reporting and Data System (PIRADS v1/v2) recommendations and included T2-weighted imaging, dynamic contrast-enhanced imaging and diffusion-weighted
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imaging sequences. Specialized uro-radiologists reported the mpMRIs. Baseline whole-body restaging imaging (68-Gallium Prostate-Specific Membrane Antigen (PSMA) PET-CT scan, bone scan or choline PET PET-CT scan) was performed to exclude evidence of local or distant metastases.
IRE Procedure
Salvage IRE was performed using the Nanoknife® system (Angiodynamics, NY, USA) by a single urologist (PS). Patients were placed in the lithotomy position following general anaesthesia. Intravenous muscle paralysis and single-shot antibiotic prophylaxis were administered, followed by insertion of an indwelling urethral catheter. The needle electrodes (18-gauge) were placed through the perineum using TRUS guidance with a 5x5 mm brachytherapy template grid, surrounding the predefined treatment area with an extra safety margin of 5 (n=1) and 10mm (n=17), based on biopsy and MRI workup. No Denonvilliers hydrodissection was performed. The number of electrodes and active tip length depended on the required ablation size based on the recurrent tumour volume. Ten test pulses were delivered with standard system settings (1500V/ cm, pulse length of 70 (n=7) or 90 μs (n=11)). The pulse length was changed to comply with international standards after the first 7 cases. When the obtained direct current of the test pulses reached the required current for the ablative effect of IRE (20 – 40 ampere between each electrode pair), the remaining 80 treatment pulses were administered. Patients were discharged within 24 hours with oral antibiotics. The indwelling catheter was removed within 5 days.
Follow-up
Safety assessment
The NCI Common Terminology Criteria for Adverse Events (CTCAE version 4.0) were used to report adverse event and safety data.
Patient-reported quality of life assessment
The Expanded Prostate Cancer Index Composite (EPIC) with specific urinary, sexual and bowel domains,25 the AUA symptom score,26 and the SF-12 Physical and Mental
Component Summary (SF12-physical/SF12-mental)27 questionnaires were used to
prospectively collect patient-reported QOL outcome data. Clinical data managers sent out and collected these questionnaires by mail at baseline, 6 weeks, 3, 6 and 12 months.
Oncological outcomes
T2-weighted MRI was performed 1 week after the IRE procedure to evaluate if the predefined treatment area was completely covered within the ablation zone. The follow-up mpMRI was performed at 6 months following the recommendations of the Prostate Imaging Reporting and Data System (PI-RADS v1/v2) committee. The PI-RADS was used to score untreated prostate tissue and the ablation zone was scored with a dichotomous outcome, either ‘suspicious’ or ‘non-suspicious’ for residual in-field PCa. PSA was sequentially monitored. Follow-up PSMA PET-CT was performed in case of biochemical failure using the Phoenix definitions (PSA nadir + 2 μg/L). Our institutional protocol follows the recommendations of the consensus guidelines, with a systematic biopsy outcome at 12 months.24
Analysis
Primary outcomes
Rates of recto-urethral fistula and adverse events using CTCAE were recorded. Patient-reported quality of life outcomes were Patient-reported for patients that consented for QoL assessment and completed at least 6 months of follow-up.
Secondary outcomes
Imaging-based oncological control was determined using the 6-months mpMRI. Suspicion for residual PCa was reported when the mpMRI results for out-field regions was PI-RADS score of 3-5 and for in-field; ‘suspicious’. Biochemical failure was defined using two definitions; PSA nadir + 2 μg/L (Phoenix) and PSA nadir + 1.2 μg/L (Stuttgart,28).
Any Gleason sum ≥6 (ISUP grade 1-5) was considered as a positive biopsy outcome. PCa found inside or adjacent to the ablation zone was classified as in-field failure, while PCa found in untreated prostate tissue was classified as out-field failure.
Statistical analysis
Wilcoxon’s Signed Rank Test was used to assess QoL differences over time in paired continuous variables (two-tailed). SPSS v23 was used to perform all analyses and statistical significance was set at p<0.05.
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RESULTS
Baseline characteristics
A total of 18 men (median age of 71 years) were treated between May 2013 and June 2016 with minimum 6-month follow-up data available. Median time to recurrence after radiotherapy was 96 months (IQR 72-132). Median follow-up was 21 months (IQR 14-28) with patients being treated in 2013 (n=1), 2014 (n=3), 2015 (n=9) and 2016 (n=5). No patient received a recent or combined transurethral resection of the prostate. The baseline characteristics are shown in Table 2, including previous primary radiotherapy, pre-treatment MRI and biopsy results. On baseline imaging two patients underwent Choline PET-CT only instead of the combination with mpMRI; one patient was ineligible to undergo mpMRI due to a cardiac pacemaker and one patient refused restaging imaging.
Peri-operative results
In all patients (100%, n=18/18) a single ablative procedure was performed, targeting one lesion. In the majority, 4 electrodes were used (89%, n=16/18), with the other two procedures performed with 5 electrodes. IRE was performed in various (overlapping) segments of the prostate, including the anterior (n=5), posterior (n=13), apical (n=5), base (n=1) and apex-to-base segment (n=12). All patients were discharged home within 24 hours and the indwelling catheter was removed within five days post-treatment in 94% (n=17/18) of the patients. In Table 3 all peri-operative data is displayed.
Safety outcomes
No peri-operative adverse events occurred. Five patients (28%, n=5/18) described pain, urgency and mild haematuria postoperatively, not requiring any intervention (CTCAE grade 1). In two patients grade 2 CTCAE adverse events were recorded postoperatively (n=2). In one these patients severe urinary continence post-IRE occurred due to urgency, which mitigated at 6 weeks to urinary dribbling requiring one pad per day. The other patient required seven days of catheterization for postoperative urinary retention, most likely due to pre-existing lower urinary tract symptoms. No high-grade adverse events occurred (CTCAE grade 3 or higher) and no patients developed recto-urethral fistula.
Table 2. Baseline characteristics (n=18) before IRE & before initial Tx
Variable Value
Age (years, median; range) 71 (68-75) 63 (55-67)
Serum PSA (μg/L, median; IQR) 3.5 (3.2-8.4) 8.6 (6.1-10.8)
Prostate volume on MRI (mL, median; IQR) 23 (15-30)
Previous Treatment LDR Brachytherapy 10 HDR Brachytherapy 3 EBRT 3 EBRT + HDR brachytherapy 2 MRI results (n=15*) PIRADS < 3 2 PIRADS 3 3 PIRADS 4 5 PIRADS 5 5* Biopsy results
Transperineal biopsies (+ - targeted cores) n= 17 n=3
Number of cores taken (median; IQR) 22 (14-27) 22 (13-32)
Number of positive cores (median; IQR) 4 (3-5) 3.5 (3-5)
TRUS biopsies (+/- targeted cores) n= 1 n= 15^
Number of cores taken (median; IQR) 21 21.5 (15-28)
Number of positive cores (median; IQR) 2 4 (3-5)
Max. % core involvement (median; IQR) 19 (15-28) 24 (12-35)
Gleason score
Gleason 3 + 3 (ISUP Grade 1) 0 6
Gleason 3 + 4 (ISUP Grade 2) 6 6#
Gleason 4 + 3 (ISUP Grade 3) 5 4
Gleason 4 + 4 (ISUP Grade 4) 2 0
Gleason ≥4 + 5 (ISUP Grade 5) 5 1
Tx: treatment. *2 patients underwent choline-PET/CT instead MRI pre-treatment, 1 had a cardiac pacemaker. # one patient
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Table 3. Perioperative data
Procedure parameter Value
Active tip length in mm (range) 10-20
Minimum interelectrode distance in mm (median, IQR) 9 (7-10) Maximum interelectrode distance in mm (median, IQR) 17 (13-19)
Minimum voltage (median, IQR) 1440 (1178-1628)
Maximum voltage (median, IQR) 2460 (2063-2670)
Minimum amperage (median, IQR) 22 (20-27)
Maximum amperage (median, IQR) 40 (37-46)
Catheterization time in days (median, IQR)* 3.5 (2-5)
Hospital stay in days (median, IQR) 1 (1-1)
QoL and functional outcomes
Eleven of the 18 patients (61%) consented for QoL assessment and completed at least 6 months of follow-up. There were no statistically significant declines observed in the QoL outcomes on the EPIC bowel domain (p=0.29), physical (p=0.17) and SF12-mental (p=0.77) questionnaires at 6 months post-IRE. Baseline sexual function was low as expected, and salvage patients experienced a significant further decline on the EPIC Sexual domain (median of 38 to 24, p=0.028) at 6 months post-treatment. Urinary domain QoL deteriorated marginally on the EPIC questionnaire (median of 96 to 92, p=0.074) but not on the AUA symptom score (p=0.77). A total of 73% (n=8/11) of the patients that were pad-free continent at baseline remained pad-free continent at 6 months. Three patients required urinary pads for urinary dribbling, of which this persisted up to 12 months in only one patient. Erections sufficient for intercourse were preserved in 33% (n=2/6) and 50% (n=2/4) of the patients at 6 months and 12 months, respectively. One patient recovered at 12 months from erectile dysfunction. 91% (n=10/11) of the patients were either satisfied or extremely satisfied with their treatment. Figure 1 shows the median summary scores over time for QOL outcomes. In Table 4 all outcomes are summarized by questionnaire.
Table 4. Quality of life and functional outcomes (median, interquartile range)
Questionnaire Baseline 3 mo 6 mo 12 mo
Difference baseline and 6 mo
EPIC urinary function
summary score 96 (81-98) 83 (72-96) 92 (65-95) 81 (63-95) No (p=0.074) EPIC sexual function
summary score 38 (31-77) 31 (26-58) 24 (10-42) 31 (16-35) Yes (p=0.028) EPIC Bowel function
summary score 96 (84-98) 95 (82-98) 98 (86-100) 96 (93-98) No (p=0.29) AUA score 5 (2-6) 7 (4-9) 4 (4-7) 7 (3-16) No (p=0.77) SF-12 Physical component score 56 (51-57) 56 (55-56) 55 (50-56) 56 (55-57) No (p=0.17) SF-12 Mental component score 58 (56-61) 58 (57-60) 58 (56-60) 55 (53-58) No (p=0.77) Oncological outcomes
6-month mpMRI was performed in 13 patients. Two patients declined mpMRI follow-up, two patients developed metastatic disease before mpMRI endpoint (PCa and squamous cell skin cancer) and one patient is awaiting mpMRI. The mpMRI was clear in 85% (n=11/13), and in two patients the mpMRI identified a single out-field region of interest (true-positive and false-positive, respectively).
Median nadir PSA was 0.39 μg/L (IQR 0.04-0.43). A total of 3 (17%) and 4 (22%) patients experienced biochemical failure using the Phoenix and Stuttgart definitions of biochemical failure, respectively. The Phoenix definitions of biochemical failure identified 3 out the 4 patients with recurrent or metastatic PCa, without false-positives. All four patients with recurrent or metastatic PCa were identified using the Stuttgart definitions, without false-positives. Follow-up PSMA PET-CT was performed in the three patients with biochemical failure (Phoenix), showing local recurrence, bone metastases and solitary pelvic lymph node disease, respectively. Salvage robotic lymph node dissection was performed on the patient with pelvic lymph node disease, achieving biochemical control.
Follow-up biopsies were performed in 10 patients with a median of 20 cores. Nine patients underwent extensive TTMB and one received transperineal-targeted biopsies. Three patients declined follow-up biopsies, two patients developed metastatic disease before biopsy endpoint (PCa and squamous cell skin cancer) and another three patients (median nadir PSA of 0.16 μg/L) are awaiting follow-up biopsies. 80% of the patients
7
were clear of any PCa on follow-up biopsy, whereas two patients had significant PCa on follow-up biopsy (both Gleason score 4+5=9/ISUP 5). One patient had in-field residual disease, which was treated with ADT. The other patient had out-field residual disease retreated with salvage IRE without any complications. The patient that had in-field residual disease was treated with a safety margin of 5mm (n=1/1), while no in-field failure occurred in patients treated with a safety margin of 10mm (n=0/9). The intention-to-treat oncological control was 67% (n=8/12). In Table 5 the oncological outcomes are summarized. Figure 2 illustrates T2-weighted MRI images following IRE for a patient previously treated with LDR-brachytherapy.
Figure 1. Median summary scores for the EPIC urinary, sexual and bowel domains, AUA
symptom score and SF-12 Physical and Mental questionnaires. The error boxes display the interquartile ranges.
Figure 2. T2-weighted MRI-scans at baseline (a), 1 week (b) and 6 months (c) following IRE in a
patient initially treated with LDR.
Table 5. Oncological follow-up
Variable Value
Nadir PSA (μg/L, median; IQR) 0.39 (0.04-0.43)
Phoenix Biochemical Failure (frequency) 3
Stuttgart Biochemical Failure (frequency) 4
MRI results n = 13
Clear 11 (84.6%)
In-field lesions 0
Out of field lesions 2 (15.4%)
Biopsy results n = 10
Number of cores taken (median, IQR) 20 (15-26)
Number of positive cores (median, IQR) 0 (0-1)
Clear on Biopsy 8 (80%)
Significant in-field disease all patients 1 (10%)
Significant out-field disease 1 (10%)
Gleason 4 + 5 (ISUP Grade 5) 2
DISCUSSION
The main aim of this study was to evaluate the initial feasibility and safety of salvage focal IRE for localized, radio-recurrent PCa. No high-grade adverse events or recto-urethral fistulae occurred during follow-up, suggesting salvage focal IRE is safe. Moreover, good
7
intra-prostatic oncological control was found, with only two cases of intra-prostatic residual/recurrent PCa. Our data also show the difficulty to truly rule out any metastatic disease at baseline as two patients developed metastatic disease within 12 months following IRE. The use of 68-Ga PSMA PET CT scanning has been shown to detect PSMA avid disease even at low PSA levels in patients with a biochemical recurrence after primary radiotherapy.29 This may be used in future trial to rule out metastatic disease
at baseline. Following the consensus guidelines on focal salvage ablative therapy,24
treatment planning and follow-up was performed using extensive template-mapping as no imaging modality has been previously validated in localizing (residual) radio-recurrent PCa. Our institutional analysis of primary IRE for localized PCa showed that in-field oncological control was superior in patients treated with an increased safety margin (10mm) compared to patients treated with a limited safety margin (5mm). This is in line with findings of le Nobin et al.30, stating that a 9mm safety margin should be
respected. That finding seems to apply to the salvage cohort as well although numbers are too small to draw any firm conclusions. All cases with residual or local/distant metastasis were identified with the Stuttgart definitions of biochemical failure, whereas the Phoenix definitions only missed one case, however, this too needs confirmation in a larger cohort. Four patients without biochemical failure (median nadir PSA of 0.05 μg/L) did not receive follow-up biopsies due to refusal (n=3) or ineligibility (metastatic squamous cell skin cancer) and another three patients with low nadir PSA are awaiting biopsies. This could have underestimated the biopsy-based oncological control and the failure to biopsy the entire cohort limits our biopsy-based outcomes. On the contrary, we did not biopsy the patient that developed metastatic PCa before biopsy endpoint (PSA of 13 μg/L).
Salvage patients experienced a decline in sexual and urinary QoL, which is in line with other salvage trials6 and most likely due to the retreatment of already affected tissue
as the baseline sexual function scores are comparable to the decrease seen at three years post EBRT and HDR.31 The low baseline sexual function for patients previously
treated with LDR, which are included in the QoL analysis, may be due to the relative old age (median of 73 years). The rates of urinary continence and erectile dysfunction are relatively high compared to other focal salvage trials,6,13,14,32,33 but this is most likely
the result of the 6-month evaluation point, low baseline sexual function and the old age of our cohort (median of 71 years). The largest series on focal salvage ablative therapy has been performed with HIFU and included 150 men with a median follow-up of 35 months. Biochemical failure occurred in 51.3% (n=77/150) with a complication rate of 11.3% (including 3 cases of urethral fistula and 1 case of osteitis pubis). The QoL outcomes were limited due to missing data but comparable to our 12-month results; 87.5% (n=42/48) remained pad-free continent at 2 years and 58.3% remained potent
(n=7/12). In the setting of focal IRE as primary treatment it has been shown that erectile function improved up to 12 months.23 Like with other PCa treatments, baseline age
and sexual function may be significant determinants to develop erectile dysfunction following treatment.34
Our outcomes are limited by the small sample size, short follow-up, heterogeneity in baseline imaging and single-centre retrospective nature of this study, which included the initial learning curve of the single surgeon. This confounds the conclusions that can be drawn for this study. Moreover, patients had to cover medical expenses, which may have portended a bias towards higher treatment satisfaction. However, our main aim was to establish the feasibility and safety of IRE for radio-recurrent PCa, with evaluation of intraprostatic oncological control by extensive template-mapping biopsies before and after the IRE-procedures. More robust long-term data is required and based on these initial results a prospective multi-centre study (FIRE trial, ACTRN12617000806369) has been initiated (currently enrolling), evaluating focal IRE for localized, radio-recurrent PCa.
In conclusion, our short-term safety, QoL and oncological control data demonstrate that focal IRE is a feasible salvage option for localized radio-recurrent PCa. A prospective multi-centre study is initiated (FIRE-trial) that will provide further insight into the ability of focal IRE to obtain oncological control with acceptable patient morbidity. Patients need to be counselled about the possibility of impaired short-term sexual and urinary QoL.
Acknowledgments: Quoc Nguyen from Australian Prostate Cancer Research
Centre-NSW (APCRC-Centre-NSW), IT Applications Group and CANSTO Database at Garvan Institute. This research is supported by The Department of Health and the Australian Prostate Cancer Research Centre-NSW, The National Health and Medical Research Council and St Vincent’s Prostate Cancer Centre. Funding/Support and role of the sponsor: Funding of this study at St Vincent's Private Hospital Sydney is supported through the Australian Commonwealth Department of Health, Australian Prostate Cancer Research Centre-NSW and the St Vincent's Prostate Cancer Centre. Financial disclosures: The authors have nothing to disclose.
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