Cryosurgical Ablation of Renal Cell Carcinoma

Safety and effectiveness of percutaneous renal cryoablation with conscious sedation

OBJECTIVE

To investigate complications and treatment failure rates of percutaneous renal cryoablation (PRC) for small renal masses under local anaesthesia and conscious sedation (LACS), to assess the safety and effectiveness of this approach, as PRC is typically performed under general anaesthesia (GA).

PATIENTS AND METHODS

We retrospectively reviewed PRC under LACS from 2003 to 2017. We analysed perioperative parameters between patients who successfully underwent PRC under LACS and patients with post-procedural complications or treatment failure (renal mass enhancement after successful intraoperative tumour ablation). Two-sided non-parametric and Fisher's exact tests were performed to compare uncomplicated or disease-free PRC with the complication or treatment failure group, respectively.

RESULTS

A total of 100 PRCs under LACS were performed during the study period. Of these patients, six patients had at least one postoperative complication (6%), and treatment failure was diagnosed in nine patients (9%) after PRC [mean (SD) follow-up of 42.7 (26.6) months]. The procedural failure rate was 1%. No ablations were converted to GA. The mean tumour size was smaller in patients who had no complications during PRC compared to those who did, at a mean (SD) of 2.2 (0.6) cm vs 3.0 (1.0) cm (P = 0.039). The use of more intraoperative probes during the PRC was also associated with complications, at a mean (SD) 3.0 (1.4) vs 1.8 (0.8) (P = 0.021).

CONCLUSIONS

PRC under LACS is an effective and safe procedural approach for managing small renal masses with low complication, treatment failure, and procedural failure rates. Larger renal masses and intraoperative use of multiple probes is associated with an increased risk of PRC complications.

ABBREVIATIONS

BMI: body mass index; CCI: Charlson Comorbidity Index; GA: general anaesthesia; LACS: local anaesthesia and conscious sedation; PRC: percutaneous renal cryoablation; R.E.N.A.L.: Radius, Exophytic/Endophytic, Nearness, Anterior/Posterior, Location.

Therapeutic potential of irreversible electroporation in sarcoma

Irreversible electroporation is a newly developed nonthermal tissue ablation technique in which certain short-duration electrical fields are used to permanently permeabilize the cell membrane to disrupt cellular homeostasis. This disruption of cellular homeostasis initiates apoptosis, which leads to permanent cell death. Sarcomas are generally divided into soft-tissue and bone sarcomas based on their different mesenchymal origins and anatomical locations. Each of these sarcomas present in different ways, exhibit different behaviors and prognoses, and present unique therapeutic challenges. In this article, a series of recently conducted irreversible electroporation treatment for sarcomas based on local nonthermal ablation are summarized, and the therapeutic potential of this newly developed technique is assessed.

Histomorphometric assessment of bone necrosis produced by two cryosurgery protocols using liquid nitrogen: an experimental study on rat femurs

Objective

The aim of this study was to evaluate the effects of liquid nitrogen cryosurgery on the femoral diaphysis of rats.

Material and Methods

The femoral diaphyses of 42 Wistar rats were exposed to three local and sequential applications of liquid nitrogen for 1 or 2 min, intercalated with periods of 5 min of passive thawing. The animals were sacrificed after 1, 2, 4 and 12 weeks and the specimens obtained were processed and analyzed histomorphometrically.

Results

The depth and extent of peak bone necrosis were 124.509 μm and 2087.094 μm for the 1-min protocol, respectively, and 436.424 μm and 12046.426 μm for the 2-min protocol. Peak necrosis was observed in the second experimental week with both cryotherapy protocols.

Conclusions

The present results indicate that the 2-min protocol produced more marked bone necrosis than the 1-min protocol. Although our results cannot be entirely extrapolated to clinical practice, they contribute to the understanding of the behavior of bone tissue submitted to different cycles of liquid nitrogen freezing and may serve as a basis for new studies.

Thermochemical Ablation: A Device for a Novel Interventional Concept

Solid focal and oligometastatic malignancies are appropriate targets for minimally invasive ablative procedures. Thermochemical ablation is an experimental minimally invasive procedure, which exploits certain features of current thermal and chemical tumor ablation therapies. Engineering principles have been used to design a device, which has been research-proven-capable of coagulating tissue through the combination of a thermal and chemical insult. This interventional device completes this assignment by separately guiding the flow of chemical reagents, drawn from auxiliary systems, to a point at the distal tip of an assembled apparatus. At this position, the respective flow-streams converge and undergo an exothermic reaction to produce a heated, hyperosmolar solute, which serves to ablate the targeted tissue. Ex and in vivo studies have confirmed the utility of this device and the physiologic toleration of this interventional concept.

CT-guided percutaneous cryoablation of renal masses in selected patients

PURPOSE

We analysed our experience with computed tomography (CT)-guided percutaneous cryoablation (PCA) in patients who were not surgical candidates or refused surgery for small to medium-sized renal masses.

MATERIALS AND METHODS

Two freezing cycles were applied and separated by a passive warming cycle using 1.7- and 2.4-mm cryoprobes under either general anaesthesia or sedation based on patient positioning and respiratory status. Postoperative monitoring included haematological and biochemistry evaluation and CT scan 24 h after PCA. Follow-up consisted of a multislice CT scan at 1 month and every 3 months in the first year then every 6 months thereafter.

RESULTS

Thirty-seven patients (38 lesions) underwent 40 PCA procedures; 5/37 (13.5%) had a solitary kidney. Median mass size was 35 (range 12-70) mm. No complications occurred during the procedure. Clavien grade ≥2 anaemia occurred in two patients (5.4 %): one patient required 1 U of packed red blood cells; the other required an arterial embolisation. Serum creatinine did not increase in any case. Two patients showed persisting or recurrent disease at 1 and 9 months, respectively, and both could be re-treated with PCA. All other patients showed a hypodense mass 3 months after PCA, with no contrast enhancement. Subsequent examinations showed that lesion sizes decreased and CT densitometry remained stable or increased minimally, also with no contrast enhancement.

CONCLUSIONS

PCA proved relatively easy and safe and could be considered an effective alternative for patients who are not surgical candidates or refuse surgery, as well as in patients with medium-sized lesions.

Current status of laparoendoscopic single-site surgery in urology

PURPOSE

Laparoendoscopic single-site surgery (LESS) uses single incisions for the introduction of instruments through a specially designed multi-lumen single port (multi-port) for the performance of several urologic procedures.

METHODS

Literature review regarding the LESS approach took place on May 2009 and the experiences of our institutions were also included.

RESULTS

Almost all urologic intra-abdominal and pelvic procedures have been successfully and safely performed with the LESS approach. Nevertheless, current experience is limited and there are significant technical challenges to the performance of LESS techniques.

CONCLUSIONS

Wider adaptation of the approach requires refinement of LESS instrumentation to overcome the technical challenges of the approach. The improved outcome should also be documented with further clinical evaluation.

Prospective analysis of the safety and efficacy of percutaneous cryoablation for pT1NxMx biopsy-proven renal cell carcinoma

PURPOSE

Our objective was to determine the efficacy and safety of image-guided, percutaneous cryoablation for American Joint Committee on Cancer pT1ANxMx and pT1BNxMx biopsy-proven renal cell carcinoma (RCC).

MATERIALS AND METHODS

Computed tomography (CT)-guided, percutaneous cryoablation was used to treat 117 renal lesions in 113 consecutive patients with pT1NxMx RCC. All 117 ablations were included in the safety analysis, and complications were categorized according to Common Terminology Criteria for Adverse Events version 3.0 (CTCAE v3.0). Eighty-one lesions were biopsy-proven RCC and were included in the efficacy analysis. Technical success was defined as the "ice-ball" covering the entire lesion plus a minimum 5-mm margin. Efficacy was defined as complete lack of enhancement and continuous decrease in size on subsequent follow-up imaging studies.

RESULTS

Technical success was 100%, with 15% of ablations requiring air or saline injection to prevent nontarget ablation. We recorded a 7% rate of clinically significant complications (CTCAE category≥2) and 0% mortality. Renal function was not adversely affected. Seventy percent of patients were discharged to home on the same day. Efficacy was 98.7% for a median follow-up of 67 weeks (range 7-172). For the subgroup of patients that reached a median follow-up of 2 (n=59) and 3 years (n=13), efficacy was 98.3 and 92.3%, respectively. Cancer specific survival was 100%.

CONCLUSIONS

CT-guided, percutaneous cryoablation has an excellent safety and efficacy profile for stage T1A and T1B RCC; however, longer follow-up is needed to compare it with other nephron-sparing surgical treatments. It is a great option for nonsurgical patients, those in whom renal function cannot be further sacrificed, and those at risk for metachronous lesions.

Cryoimmunotherapy in urologic oncology

Cryoablation is gaining acceptance as a primary treatment of localized as well as a salvage therapy of metastatic urologic malignancies. Anecdotal clinical reports suggest cryoablation can induce a systemic anti-tumor immune response; this phenomenon has been confirmed in animal models. To capitalize on this stimulatory effect of cryotherapy for control of advanced malignancies, it must be further intensified. This article reviews the existing evidence regarding cryoimmunology and discusses the mechanisms for generation of an anti-tumor immune response. Several immunotherapy approaches that can be combined with cryoablation to devise a cryoimmunotherapeutic strategy with potential to affect the progression of metastatic disease are described.

Decision tree for laparoscopic partial nephrectomy versus laparoscopic renal cryoablation for small renal masses

PURPOSE

We propose an algorithm to help guide surgeons' decisions between laparoscopic partial nephrectomy (LPN) and renal laparoscopic cryoablation (LCA) based on preoperative parameters and outcomes defined in the literature.

PATIENTS AND METHODS

From July 2004 to December of 2007, we performed 51 LPNs and 22 LCAs. We formulated an algorithm between LPN and LCA based on outcomes from published series. Candidates for LPN are younger than 70 years; have few comorbidities; masses < or = 7 cm; and solitary, solid, and or cystic masses with an exophytic or mesophytic location. Candidates for LCA are 70 years old or older, with multiple comorbidities, masses < or = 3.5 cm, multiple masses, solid masses only, and include endophytic or hilar tumors. We then applied this decision tree to our series.

RESULTS

Our results for LPN are statistically similar to the published series except there was a higher positive margin rate in our series (11.8 v 3.5%). Our LCA series had older patients (71 v 65 y), larger masses (3.2 v 2.5 cm), and a higher rate of bleeding necessitating transfusion (18%). We applied the algorithm to all 73 patients in our series. It estimated that 45 patients should undergo LPN and 28 should undergo LCA. A correlation between the predicted surgery and the surgery performed was seen, but approximately one in five patients would have a change in the surgery performed.

CONCLUSIONS

This algorithm validates decisions surgeons are already making between LPN and LCA. While not a perfect model, it can be used to help simplify decisions between these two minimally invasive procedures to achieve optimal outcomes.

Perioperative morbidity of laparoscopic cryoablation of small renal masses with ultrathin probes: a European multicentre experience

BACKGROUND

Low morbidity has been advocated for cryoablation of small renal masses.

OBJECTIVES

To assess negative perioperative outcomes of laparoscopic renal cryoablation (LRC) with ultrathin cryoprobes and patient, tumour, and operative risk factors for their development.

DESIGN, SETTING, AND PARTICIPANTS

Prospective collection of data on LRC in five centres.

INTERVENTION

LRC.

MEASUREMENTS

Preoperative morbidity was assessed clinically and the American Society of Anaesthesiologists (ASA) score was assigned prospectively. Charlson Comorbidity Index (CCI) and Charlson-Age Comorbidity Index (CACI) scores were retrospectively assigned. Negative outcomes were prospectively recorded and defined as any undesired event during the perioperative period, including complications, with the latter classed according to the Clavien system. Patient, tumour, and operative variables were tested in univariate analysis as risk factors for occurrence of negative outcomes. Significant variables (p<0.05) were entered in a step-forward multivariate logistic regression model to identify independent risk factors for one or more perioperative negative outcomes. The confidence interval was settled at 95%.

RESULTS AND LIMITATIONS

There were 148 procedures in 144 patients. Median age and tumour size were 70.5 yr (range: 32-87) and 2.6 cm (range: 1.0-5.6), respectively. A laparoscopic approach was used in 145 cases (98%). Median ASA, CCI, and CACI scores were 2 (range: 1-3), 2 (range: 0-7), and 4 (range: 0-11), respectively. Comorbidities were present in 79% of patients. Thirty negative outcomes and 28 complications occurred in 25 (17%) and 23 (15.5%) cases, respectively. Only 20% of all complications were Clavien grade > or = 3. Multivariate analysis showed that tumour size in centimetres, the presence of cardiac conditions, and female gender were independent predictors of negative perioperative outcomes occurrence. Receiver operator characteristic curve confirmed the tumour size cut-off of 3.4 cm as an adequate predictor of negative outcomes.

CONCLUSIONS

Perioperative negative outcomes and complications occur in 17% and 15.5%, respectively, of cases treated by LRC with multiple ultrathin needles. Most of the complications are Clavien grade 1 or 2. The presence of cardiac conditions, female gender, and tumour size are independent prognostic factors for the occurrence of a perioperative negative outcome.

The UCI Seldinger technique for percutaneous renal cryoablation: protecting the tract and achieving hemostasis

PURPOSE

To describe our Seldinger technique of percutaneous renal cryoablation that was devised to facilitate renal biopsy, cryoprobe placement, and instillation of adjunctive hemostatics while protecting surrounding tissues from cryoinjury.

PATIENTS AND METHODS

This approach was used to manage 13 renal masses in 12 adult patients. Under CT-fluoroscopic guidance, an access needle was inserted to abut the surface of the tumor, followed by an Amplatz super-stiff guidewire and a customized coaxial catheter system, which was used as a conduit for needle biopsy, cryoprobe insertion, and FloSeal instillation. In addition, a porcine model was used to compare the temperature readings adjacent to the sheathed and the unsheathed cryoprobe during percutaneous renal cryoablation.

RESULTS

In all patients, the use of this access approach was accomplished without incident. Two patients needed blood transfusions. No patient had significant skin, muscle, or nerve debility. At a mean follow-up of 11 months, none had evidence of persistent disease on CT or MRI contrast imaging. In the porcine model, the customized sheath protected the surrounding tissues from reaching temperatures below 5 degrees C while temperatures down to -15 degrees C were obtained when no insulating sheath was used.

CONCLUSIONS

A modified Seldinger technique enabled us to perform percutaneous renal cryotherapy through a single access channel, which facilitated access for biopsy, cryoprobe placement, and instillation of hemostatic agents. This approach may provide a protective barrier against cryogenic damage to neighboring tissues and could theoretically help minimize the chance of tract seeding.

Thermal ablation: update and technique at a high-volume institution

In the era of nephron-sparing surgery for small renal tumors, thermal ablation is gaining popularity. Both cryoablation and radiofrequency ablation have well-demonstrated short-term oncologic efficacy and safety. This article shares the current literature and the radiofrequency ablation technique at a high-volume institution. Cases are presented that illustrate solutions to obstacles frequently encountered during percutaneous ablation of renal masses.

Minimally invasive surgery using ablative modalities for the localized renal mass

Due to a number of evolving devices and modalities to treat the small, localized renal mass, the physician and patient have the opportunity to choose an appropriate therapy from several treatment options. Minimally invasive surgery to ablate a localized renal tumor is an alternative strategy to nephron-sparing surgery for the small renal mass. Even though partial nephrectomy has been established as an optimal technique for nephron-sparing surgery, patients who have comorbidities and renal insufficiency would potentially benefit from less invasive treatment. With respect to those concerns, several articles are discussed here regarding thermal ablative therapy for the small renal mass along with oncological outcomes and complications among these modalities compared to conventional procedures. In this review, a comprehensive PubMed search was conducted. For the purposes of reviewing the current status of thermal ablative modalities for the small renal mass, only articles written in English published from 1992 to 2009 were considered. Cryoablation and radiofrequency ablation are the most utilized and potentially promising therapies that are evolving as nephron-sparing minimally invasive surgery for patients with a localized renal tumor. High-intensity focused ultrasound, a relatively new modality to treat the renal mass, needs further study. All modalities require long-term follow up with unified reporting methods in terms of patient selection, pre- and post-treatment evaluation, treatment description, and analysis of outcome.

Safety and efficacy of CT-guided percutaneous cryoablation for renal cell carcinoma

PURPOSE

Image-guided percutaneous cryoablation is a treatment alternative for selected patients with renal cell carcinoma (RCC). The objective of the present study was to present the safety and efficacy of percutaneous cryoablation.

MATERIALS AND METHODS

The study included 51 lesions in 46 consecutive patients treated with computed tomography (CT)-guided percutaneous cryoablation. Results were based on 40 RCCs with follow-up. Patients had baseline history and physical and laboratory examinations and renal CT or magnetic resonance (MR) imaging and were followed every 3 months. Biopsy of all lesions was performed before or at the time of the procedure. Efficacy was defined as a complete lack of enhancement on follow-up contrast agent-enhanced CT or MR imaging. Lesion size was also followed and correlated with lack of enhancement. Short- and long-term complications were tabulated.

RESULTS

The technical success rate was 100%, with 20% of cases requiring some form of thermal protection of an adjacent organ. During follow-up (median, 28 weeks; range, 4-81 weeks), the efficacy rate was 100% for lesions smaller than 7 cm. The incidence of significant complications was 18% (8% CTAE), mostly (10%) intercostal or genitofemoral nerve injury. All patients with complications recovered fully, and there were no mortalities. There was no change in creatinine levels, and no patient developed renal failure as a result of cryoablation.

CONCLUSIONS

CT-guided percutaneous cryoablation resulted in complete response for lesions as large as 4 cm. It may also be a viable alternative for nonsurgical candidates with lesions as large as 7 cm. It has a high efficacy rate, and its modest complications are not only comparable to those of other treatment modalities, but also appear to be reversible.

Percutaneous and laparoscopic cryoablation of small renal masses

PURPOSE

We reviewed our 4-year experience with percutaneous cryoablation and laparoscopy for treating small renal masses.

MATERIALS AND METHODS

After institutional review board approval we retrospectively analyzed renal cryoablation procedures performed between March 2003 and October 2007. An in-depth analysis was performed concerning demographics, hospital course and short-term outcome with respect to percutaneous vs laparoscopic cryoablation.

RESULTS

A total of 37 patients underwent treatment for 43 renal masses. Of the 37 patients 19 underwent laparoscopic cryoablation (24 tumors) and 18 underwent percutaneous cryoablation (19 tumors) using computerized tomography fluoroscopy. For percutaneous cryoablation a saline instillation was used in 58% of cases to move nonrenal vital structures away from the targeted renal mass. There were 5 cases of hemorrhage requiring transfusion, all of which were associated with the use of multiple cryoprobes. The transfusion rate in the percutaneous and laparoscopic cryoablation groups was 11.1% and 27.8%, respectively. Operative time was significantly longer in the laparoscopic cryoablation group compared to the percutaneous cryoablation group at 147 (range 89 to 209) vs 250.2 (range 151 to 360) minutes, respectively. The overall complication rate (including transfusion) was lower in the percutaneous cryoablation group compared to the laparoscopic cryoablation group (4 of 18 [22.2%] vs 8 of 20 [40%], respectively). Hospital stay was significantly shorter in the percutaneous vs laparoscopic cryoablation group at 1.3 vs 3.1 days, p <0.0001, respectively. Narcotic use in the percutaneous cryoablation group was more than half that used by the laparoscopic cryoablation group (5.1 vs 17.8 mg, p = 0.03, respectively). Among patients with biopsy proven renal cell carcinoma during a median followup of 11.4 and 13.4 months in the percutaneous and laparoscopic cryoablation groups, cancer specific survival was 100% and 100%, respectively, and the treatment failure rate was 5.3% and 4.2%, respectively.

CONCLUSIONS

Percutaneous cryoablation is an efficient, minimally morbid method for the treatment of small renal masses and it appears to be superior to the laparoscopic approach. Short-term followup has shown no difference in tumor recurrence or need for re-treatment. Of note, hemorrhage was solely associated with the use of multiple probes.

Updates in endourology

Rapid urologic innovations in minimally invasive treatment are creating exciting new horizons in endourology. However, these new concepts are blurring the traditional boundary between endourology and oncology. Organ-sparing surgery, laparoscopy, robotics systems, and image-guided ablation techniques enable surgeons to develop specifically tailored treatments for patients. We examine recent developments and future prospects for how new technology will continue to advance the field of endourology.