Irreversible Electroporation for the Ablation of Renal Cell Carcinoma: A Prospective, Human, In Vivo Study Protocol (IDEAL Phase 2b)

Background

Irreversible electroporation (IRE) is an emerging technique delivering electrical pulses to ablate tissue, with the theoretical advantage to overcome the main shortcomings of conventional thermal ablation. Recent short-term research showed that IRE for the ablation of renal masses is a safe and feasible treatment option. In an ablate and resect design, histopathological analysis 4 weeks after radical nephrectomy demonstrated that IRE-targeted renal tumors were completely covered by ablation zone. In order to develop a validated long-term IRE follow-up study, it is essential to obtain clinical confirmation of the efficacy of this novel technology. Additionally, follow-up after IRE ablation obliges verification of a suitable imaging modality.

Objective

The objectives of this study are the clinical efficacy and safety of IRE ablation of renal masses and to evaluate the use of cross-sectional imaging modalities in the follow-up after IRE in renal tumors. This study conforms to the recommendations of the IDEAL Collaboration and can be categorized as a phase 2B exploration trial.

Methods

In this prospective clinical trial, IRE will be performed in 20 patients aged 18 years and older presenting with a solid enhancing small renal mass (SRM) (≤4 cm) who are candidates for ablation. Magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) will be performed at 1 day pre-IRE, and 1 week post-IRE. Computed tomography (CT), CEUS, and MRI will be performed at 3 months, 6 months, and 12 months post-IRE.

Results

Presently, recruitment of patients has started and the first inclusions are completed. Preliminary results and outcomes are expected in 2018.

Conclusions

To establish the position of IRE ablation for treating renal tumors, a structured stepwise assessment in clinical practice is required. This study will offer fundamental knowledge on the clinical efficacy of IRE ablation for SRMs, potentially positioning IRE as ablative modality for renal tumors and accrediting future research with long-term follow-up.

Trial Registration

Clinicaltrials.gov registration number NCT02828709; https://clinicaltrials.gov/ct2/show/NCT02828709 (archived by WebCite at http://www.webcitation.org/6nmWK7Uu9). Dutch Central Committee on Research Involving Human Subjects NL56935.018.16

[Management of malignant ureteral obstruction.]

OBJECTIVE

To describe the different therapeutic alternatives in malignant ureteral obstruction (MUO), and to analyze short and long-term results.

METHODS

We conducted a bibliographic search about MUO in Spanish and English languages in PubMed and Google Scholar. We examined the most relevant reviews, original manuscripts and their respective citations. Last search was on April 2016.

RESULTS

Polymeric double J stent is the cheapest and most accessible internal urinary diversion, but has also the shortest duration. Early and late failure rates were 0-35% and 14-49% respectively. Mean time to late failure was 3-12 months. Percutaneous nephrostomy is the safest alternative in terms of failure rates, though it has frequent complications such as tube dislodgement, and may have a negative effect on quality of life. The only metallic double J stent with enough bibliographic background is the Resonance® stent. Early failure was 0-15% and late failure 4-41%, with a mean time to late failure of 2.6-13 months. Regarding metallic stents, Memokath 051® has obtained the best results, with 0-5% early failure rates, 19-49% late failures and mean time to late failure of 7-11 months. In patients with polymeric double J stent failure, patients benefited from tandem double J stents, metallic double J catheters or metallic stents, avoiding the need of a percutaneous nephrostomy. The evidence level was low in all cases.

CONCLUSIONS

Results in MUO are very heterogeneous and have a low evidence level. Factors that influence results include stent characteristics, status and prognosis of the obstructive condition and probably patient and physician's preferences. Polymeric double J stents seem to have higher early and late failure rates than metallic double J catheters and metallic stents. Even though, the difference is not clearly evident. Prospective, multicenter, multidisciplinary trials are necessary to elucidate convenience and adequate selection of each type of stent.

Utilization of multiparametric prostate magnetic resonance imaging in clinical practice and focal therapy: report from a Delphi consensus project

Purpose

To codify the use of multiparametric magnetic resonance imaging (mpMRI) for the interrogation of prostate neoplasia (PCa) in clinical practice and focal therapy (FT).

Methods

An international collaborative consensus project was undertaken using the Delphi method among experts in the field of PCa. An online questionnaire was presented in three consecutive rounds and modified each round based on the comments provided by the experts. Subsequently, a face-to-face meeting was held to discuss and finalize the consensus results.

Results

mpMRI should be performed in patients with prior negative biopsies if clinical suspicion remains, but not instead of the PSA test, nor as a stand-alone diagnostic tool or mpMRI-targeted biopsies only. It is not recommended to use a 1.5 Tesla MRI scanner without an endorectal or pelvic phased-array coil. mpMRI should be performed following standard biopsy-based PCa diagnosis in both the planning and follow-up of FT. If a lesion is seen, MRI-TRUS fusion biopsies should be performed for FT planning. Systematic biopsies are still required for FT planning in biopsy-naïve patients and for patients with residual PCa after FT. Standard repeat biopsies should be taken during the follow-up of FT. The final decision to perform FT should be based on histopathology. However, these consensus statements may differ for expert centers versus non-expert centers.

Conclusions

The mpMRI is an important tool for characterizing and targeting PCa in clinical practice and FT. Standardization of acquisition and reading should be the main priority to guarantee consistent mpMRI quality throughout the urological community.

Electronic supplementary material

The online version of this article (doi:10.1007/s00345-016-1932-1) contains supplementary material, which is available to authorized users.

Cryoablation of small kidney tumors

INTRODUCTION

Cryoablation (CA) has been broadly used mostly in the treatment of small renal masses (SRMs). The present review aims to define the current role of CA in the treatment of SRMs by assessing clinical indications and outcomes.

METHOD

A comprehensive review on patient selection, procedural details, perioperative complications, and short/long-term oncological and functional outcomes was conducted. For each section, a take-home message was formulated with level of evidence (LoE) according to Cochrane collaboration.

RESULTS

Age and comorbidity drive the choice of ablation in SRMs, although hospital setting also influences the decision. Technically in adequate CA or first post-CA control occurs in 3-5% of laparoscopic cryoablation (LCA) or percutaneous cryoablation (PCA) series. Meta-analysis does not evidence differences in the rate of residual tumor per person-year between the approaches (0.033 LCA vs. 0.046 PCA, p = 0.25). Perioperative complications (8-25%) are erratically reported. LCA has significantly lower likelihood of complications than minimally invasive partial nephrectomy (MIPN). Systematic reviews indicate 30-month local tumor progression rate of 8.5% for LCA in renal cell carcinoma but low metastatic progression (1-4.4%). Few LCA long-term follow-up series (mean/media 48-98 months) report recurrence-free survival (RFS) and cancer-specific survival (CSS) ranges of 80-100%. For PCA, Kaplan-Meier local disease-free survival (DFS) of 95.6% at 3-5 years [32] and 5-year overall survival and local RFS of 86.3% were reported. The decrease in renal function after CA is minimal, and the only risk factor associated is the basal estimated glomerular filtration rate (eGFR).

CONCLUSION

LoE 3a/b confirms lower CA perioperative complication rate and higher local progression rate than those for MIPN. CA preserves postoperative renal functional, without any evidence of differences in mid-/long-term follow-up compared to nephron sparing surgery.

Focal vs extended ablation in localized prostate cancer with irreversible electroporation; a multi-center randomized controlled trial

Background

Current surgical and ablative treatment options for prostate cancer (PCa) may result in a high incidence of (temporary) incontinence, erectile dysfunction and/or bowel damage. These side effects are due to procedure related effects on adjacent structures including blood vessels, bowel, urethra and/or neurovascular bundle. Ablation with irreversible electroporation (IRE) has shown to be effective and safe in destroying PCa cells and also has the potential advantage of sparing surrounding tissue and vital structures, resulting in less impaired functional outcomes and maintaining men’s quality of life.

Methods/Design

In this randomized controlled trial (RCT) on IRE in localized PCa, 200 patients with organ-confined, unilateral (T1c-T2b) low- to intermediate-risk PCa (Gleason sum score 6 and 7) on transperineal template-mapping biopsies (TTMB) will be included. Patients will be randomized into focal or extended ablation of cancer foci with IRE. Oncological efficacy will be determined by multiparametric Magnetic Resonance Imaging, Contrast-Enhanced Ultrasound imaging if available, TTMP and Prostate Specific Antigen (PSA) follow-up. Patients will be evaluated up to 5 years on functional outcomes and quality of life with the use of standardized questionnaires.

Discussion

There is critical need of larger, standardized RCTs evaluating long-term oncological and functional outcomes before introducing IRE and other focal therapy modalities as an accepted and safe therapeutic option for PCa. This RCT will provide important short- and long-term data and elucidates the differences between focal or extended ablation of localized, unilateral low- to intermediate-risk PCa with IRE.

Trial registration

Clinicaltrials.gov database registration number NCT01835977. The Dutch Central Committee on Research Involving Human Subjects registration number NL50791.018.14.

Three-dimensional Technology Facilitates Surgical Performance of Novice Laparoscopy Surgeons: A Quantitative Assessment on a Porcine Kidney Model

OBJECTIVE

To determine whether the use of 3-dimensional (3D) imaging translates into a better surgical performance of naïve urologic laparoscopic surgeons during pyeloplasty (PY) and partial nephrectomy (PN) procedures.

MATERIALS AND METHODS

Eighteen surgeons without any previous laparoscopic experience were randomly assigned to perform PY and PN in a porcine model using initially 2-dimensional (2D) and 3D laparoscopy. A surgical performance score was rated by an "expert" tutor through a modified 5-item global rating scale contemplating operative field view, bimanual dexterity, efficiency, tissue handling, and autonomy. Overall surgical time, complications, subjective perception of participating surgeons, and inconveniences related to the 3D vision were recorded.

RESULTS

No difference in terms if operative time was found between 2D or 3D laparoscopy for both the PY (P = .51) and the PN (P = .28) procedures. A better rate in terms of surgical performance score was noted by the tutors when the study participants were using 3D vs 2D, for both PY (3.6 [0.8] vs 3.0 [0.4]; P = .034) and PN (3.6 [0.51] vs 3.15 [0.63]; P = .001). No complications occurred in any of the procedures. Most (77.2%) of the participating naïve laparoscopic surgeons had the perception that 3D laparoscopy was overall easier than 2D. Headache (18.1%), nausea (18.1%), and visual disturbance (18.1%) were the most common issues reported by the surgeons during 3D procedures.

CONCLUSION

Despite the absence of translation in a shorter operative time, the use of 3D technology seems to facilitate the surgical performance of naïve surgeons during laparoscopic kidney procedures on a porcine model.

Thermal ablation in renal cell carcinoma management: a comprehensive review

PURPOSE OF REVIEW

This article provides an overview of recent developments in the field of thermal ablation for renal cell carcinoma and focuses on current standard techniques, new technologies, imaging for ablation guidance and evaluation, and future perspectives.

RECENT FINDINGS

Emerging long-term data on cryoablation and radiofrequency ablation (RFA) show marginally lower oncologic outcomes compared to surgical treatment, balanced by better functional and perioperative outcomes. Reports on residual disease vary widely, influenced by different definitions and strategies in determining ablation failure. Stratifying disease-free survival after RFA according to tumor size suggests 3 cm to be a reasonable cut off for RFA tumor selection. Microwave ablation and high-intensity focal ultrasound are modalities with the potential of creating localized high temperatures. However, difficulties in renal implementation are impairing sufficient ablation results. Irreversible electroporation, although not strictly thermal, is a new technology showing promising results in animal and early human research.

SUMMARY

Although high-level randomized controlled trials comparing thermal ablation techniques are lacking, evidence shows that thermal ablation for small renal masses is a safe procedure for both long-term oncologic and functional outcomes. Thermal ablation continues to be associated with a low risk of residual disease, for which candidates should be properly informed. RFA and cryoablation remain the standard techniques whereas alternative techniques require further studies.

[Advances in ultrasound techniques for the diagnosis and staging of prostate cancer. Elastography, Doppler ultrasound, ultrasound contrast media, ultrasound quantification media and MRI fusion]

OBJECTIVES

Transrectal ultrasound-guided prostate biopsy remains the gold standard in the diagnosis of prostate cancer. Various Ultrasound modalities have been proposed to increase the cancer detection rate. Our purpose is to evaluate each of these methods , and to present its current literature and clinical utility.

METHOD

A non structured review of the current literature was conducted over these different various ultrasound modalities used during the transrectal ultrasound-guided prostate biopsied in the diagnosis of prostate cancer.

RESULTS

The data investigation of the various modalities associated sonographic features exhibits great heterogeneity and highly variable results. Some new techniques sampling present promising results with high sensitivity and specificity, thus increasing the diagnostic yield of transrectal biopsy. It seems that elastography shows encouraging figures, especially given the recent introduction of the "shearvawe" elastography that decreases the user-dependent factor.

CONCLUSIONS

The ultrasound-guided prostate biopsy has an acceptable sensitivity in the diagnosis of prostate cancer, but its specificity is still low. Various modalities associated with ultrasound are available in clinical practice in order to increase cancer detection rate. Although some promising data have been published for some of the modalities, we believe the combination of these includes validated ultrasound guided biopsy protocols to accurately target and diagnose prostate cancer.