Percutaneous radiofrequency ablation of small renal tumours in patients with a single functioning kidney: long-term results

The role of imaging in the management of renal masses

The wide availability of cross-sectional imaging is responsible for the increased detection of small, usually asymptomatic renal masses. More than 50 % of renal cell carcinomas (RCCs) represent incidental findings on noninvasive imaging. Multimodality imaging, including conventional US, contrast-enhanced US (CEUS), CT and multiparametric MRI (mpMRI) is pivotal in diagnosing and characterizing a renal mass, but also provides information regarding its prognosis, therapeutic management, and follow-up. In this review, imaging data for renal masses that urologists need for accurate treatment planning will be discussed. The role of US, CEUS, CT and mpMRI in the detection and characterization of renal masses, RCC staging and follow-up of surgically treated or untreated localized RCC will be presented. The role of percutaneous image-guided ablation in the management of RCC will be also reviewed.

Management of bleeding associated with radiofrequency ablation of benign thyroid nodules

Objective

This study was performed to explore the effective management of bleeding associated with radiofrequency ablation (RFA) of benign thyroid nodules.

Methods

Thirty-five patients with benign thyroid nodules who were treated with ultrasound-guided RFA from July 2015 to December 2016 at the Third Affiliated Hospital of Sun Yat-sen University were retrospectively reviewed. The technique efficacy, bleeding, and other complications were assessed during the follow-up period.

Results

The mean technique efficacy was 55.6%±22.8% at 1 month and 24.1%±17.1% at 6 months after the procedure. One case of an intranodular haematoma and two cases of voice change (>1 month) were observed. All patients recovered with corresponding treatment.

Conclusion

Although the incidence of haemorrhage is low, serious haematomas are life-threatening. Therefore, having a comprehensive understanding of the potential complications, an accurate clinical strategy, and adequate technical skills may prevent or help to properly manage these complications.

Long-Term Follow-Up Outcomes after Percutaneous US/CT-Guided Radiofrequency Ablation for cT1a-b Renal Masses: Experience from Single High-Volume Referral Center

Image-guided thermal ablations are increasingly applied in the treatment of renal cancers, under the guidance of ultrasound (US) or computed tomography (CT). Sometimes, multiple ablations are needed. The aim of the present study was to evaluate the long-term results in patients with renal mass treated with radiofrequency ablation (RFA) with both US and CT, with a focus on the multiple ablations rate. 149 patients (median age 67 years) underwent RFA from January 2008 to June 2015. Median tumor diameter was 25 mm (IQR 17–32 mm). Median follow-up was 54 months (IQR 44–68). 27 (18.1%) patients received multiple successful ablations, due to incomplete ablation (10 patients), local tumor progression (8 patients), distant tumor progression (4 patients) or multiple tumor foci (5 patients), with a primary and secondary technical efficacy of 100%. Complications occurred in 13 (8.7%) patients (6 grade A, 5 grade C, 2 grade D). 24 patients died during follow-up, all for causes unrelated to renal cancer. In conclusion, thermal ablations with the guidance of US and CT are safe and effective in the treatment of renal tumors in the long-term period, with a low rate of patients requiring multiple treatments over the course of their disease.

[What can/should be treated in kidney tumors and when]

CLINICAL/METHODICAL ISSUE

In the treatment of localized renal cell carcinoma, the lack of randomization in controlled trials on thermal ablation is a major limitation. The latter leads to significant study bias and it ultimately remains unclear whether the improved overall survival in favor of partial nephrectomy can actually be attributed to the treatment method.

STANDARD RADIOLOGICAL METHODS

For T1a (≤4 cm) renal cell carcinoma without lymph node and distant metastases, excellent technical and clinical results have been described after imaging-guided radiofrequency ablation and cryoablation.

METHODICAL INNOVATIONS

Low major complication rates, preservation of renal function and three-dimensional confirmation of negative ablation margins (A0 ablation) are the advantages of computed tomography (CT)-guided thermal ablation.

PERFORMANCE

According to the results of controlled (non-randomized) trials on T1a renal cell cancer, the cancer-specific survival rates are comparable between ablative and surgical techniques.

ACHIEVEMENTS

It is high time for prospective randomized controlled trials to define the actual value of percutaneous thermal ablation and partial nephrectomy in the treatment of T1a renal cell carcinoma.

PRACTICAL RECOMMENDATIONS

Apart from localized renal cell carcinoma, angiomyolipoma and oncocytoma can be treated by thermal ablation. Transarterial embolization extends the radiological spectrum for the treatment of renal tumors, either as complementary embolization (e. g. before thermal ablation of T1a and T1b renal cell carcinoma), prophylactic embolization (e. g. angiomyolipoma >6 cm), preoperative embolization (e. g. before laparoscopic partial nephrectomy) or palliative embolization (e. g. in patients with symptomatic macrohematuria due to renal cell carcinoma).

[Ablative therapy in kidney cancer: Oncological, functional, perioperative outcomes and cost]

INTRODUCTION

The incidence of kidney cancer has increased significantly over the past few decades presumably due to the increased use of imaging. The aim of this article is to describe contemporary outcomes of ablative therapy and to compare them to other therapeutic options in terms of oncological, functional, perioperative outcomes and cost.

MATERIAL AND METHODS

We searched MEDLINE^®, Embase^®, using (MeSH) words; from January 2005 through May 2017, and we looked for all the studies. Investigators graded the strength of evidence in terms of methodology, language and relevance.

RESULTS

Ninety-one articles were analyzed. We described the outcomes of ablative therapy in relation to the energy used and the approach, and compared these outcomes to the other therapeutic options in terms of oncological, functional and perioperative outcomes. We analyzed these studies in order to search for predictive factors influencing the results of ablative therapy. We also analyzed the economic burden of small renal tumor management.

CONCLUSION

The strength of evidence is based almost entirely on retrospective studies and is susceptible to the inherent limitations of this study design. Although, the evidence was low among studies, our revue showed that, in elderly patients treated with ablative therapy for cT1a tumors, the cancer-specific survival was comparable to partial nephrectomy with differences in overall survival that are explained by competing risks of death in the old population. Considering the functional results, the renal function preservation seems to be comparable between the 2 groups while the perioperative morbidity is higher in the partial nephrectomy group. The evidence base medicine at this time cannot support the extension of the indications of ablative therapy beyond the actual implementations.

Percutaneous Radiofrequency Ablation Versus Robotic-Assisted Partial Nephrectomy for the Treatment of Small Renal Cell Carcinoma

Introduction

The authors compared the oncologic outcomes of radiofrequency ablation (RFA) with robotic-assisted partial nephrectomy (RPN) for the treatment of T1 stage renal cell carcinoma (RCC).

Materials and methods

This was a retrospective data analysis of a high-volume single tertiary centre. Patients were treated with RFA or RPN following multidisciplinary decision making. Only histologically proven RCCs were included. Baseline demographics were collected, and PADUA scores of tumour features were calculated to standardize baseline anatomy. Peri-operative complications, kidney function and oncological outcomes were compared.

Results

Sixty-three cases were included in each group. Baseline renal function was poorer in RFA, and 16/63 RFA patients had tumours in single kidneys compared to 1/63 RPN cases (p < 0.001). Length of stay was shorter in RFA (1 vs. 3 days, p < 0.0001). Post-procedure renal function decline at 30 days was significantly less in RFA [(−0.8) ± 9.6 vs. (−16.1) ± 19.5 mls/min/1.73 m²; p < 0.0001]. More minor complications were recorded in RPN (10/63 vs. 4/63, p = 0.15), but local recurrence was numerically higher in RFA (6/63 vs. 1/63, p = 0.11). Disease-free survival (DFS) was not significantly different (adjusted HR = 0.6, 95 % Cl 0.1–3.7; p = 0.60). Increasing tumour size was an independent predictor of local recurrence (adjusted HR = 1.7; 95 % Cl 1.1–2.6 per cm; p = 0.02).

Conclusions

Both RPN and RFA offer very good oncological outcomes for the treatment of T1 RCC with low peri-operative morbidity and similar oncologic outcomes. RFA demonstrated fewer peri-operative complications and better preservation of renal function, whereas RPN had an insignificantly lower local recurrence rate. RFA should be offered alongside RPN for selected cases.

[Percutaneous radiofrequency ablation of renal tumors: update 2015]

BACKGROUND

Stage I renal cell carcinoma is a malignancy with a relatively good prognosis. The incidence of all renal cell carcinomas is approximately 9/100,000 persons. There are nearly 15,000 newly diagnosed patients every year (men twice as often as women).

TREND

In the last decade, a trend away from radical open resection towards nephron-sparing approaches has been observed. Currently, partial nephrectomy is the surgical gold standard for the treatment of small renal tumors. However, excellent clinical results are obtained using percutaneous radiofrequency ablation (RFA): low complication rates and preservation of the renal function.

RESULTS

Primary and secondary technical success rates are 69-100% and 90-100%, respectively. In large series, major complication rates of RFA of 0-14% are reported. A relevant deterioration of renal function after RFA is very rare. The 5-year local recurrence-free survival rates, metastasis-free survival rates, cancer-specific survival rates, and overall survival rates are 88-93, 95-100, 98-100, and 58.3-85%, respectively. In this context, the lack of appropriate long-term data is often cited as a limitation.

CONCLUSION

Different meta-analyses come to the conclusion that in case of adequate tumor and patient selection RFA shows oncologic results comparable with surgical resection. Accepted indications for RFA are T1 renal tumors in patients with advanced age, significant comorbidities, reduced renal function, single kidney, and/or no wish for operation. Predictors for the success include tumor size and location as well as operator experience. To define the real efficacy of RFA in the treatment of renal tumors, randomized controlled clinical long-term studies are indicated.

Interventional oncology in multidisciplinary cancer treatment in the 21(st) century

Interventional oncology is an evolving branch of interventional radiology, which relies on rapidly evolving, highly sophisticated treatment tools and precise imaging guidance to target and destroy malignant tumours. The development of this field has important potential benefits for patients and the health-care system, but as a new discipline, interventional oncology has not yet fully established its place in the wider field of oncology; its application does not have a comprehensive evidence base, or a clinical or quality-assurance framework within which to operate. In this regard, radiation oncology, a cornerstone of modern cancer care, has a lot of important information to offer to interventional oncologists. A strong collaboration between radiation oncology and interventional oncology, both of which aim to cure or control tumours or to relieve symptoms with as little collateral damage to normal tissue as possible, will have substantial advantages for both disciplines. A close relationship with radiation oncology will help facilitate the development of a robust quality-assurance framework and accumulation of evidence to support the integration of interventional oncology into multidisciplinary care. Furthermore, collaboration between interventional oncology and radiation oncology fields will have great benefits to practitioners, people affected by cancer, and to the wider field of oncology.