Percutaneous radiofrequency ablation with contrast-enhanced ultrasonography for solitary and sporadic renal cell carcinoma in patients with autosomal dominant polycystic kidney disease

Percutaneous radiofrequency ablation is an effective treatment option for small renal masses, comparable to partial nephrectomy

OBJECTIVES

The standard therapy for small renal masses (SRMs) remains partial nephrectomy (PN), which is associated with relatively high morbidity and complication rate. Therefore, percutaneous radiofrequency ablation (PRFA) emerges as an alternative therapy. This study aimed to compare the efficacy, safety, and oncological outcomes of PRFA versus PN.

METHODS

A multicenter non-inferiority study with retrospective analysis of 291 patients with SRMs (N0M0), who underwent PN or PRFA (2:1), recruited prospectively from two hospitals in the Andalusian Public Health System, Spain, between 2014 and 2021. Comparisons of treatment features were evaluated using the t test, Wilcoxon-Mann-Whitney U test, chi-square test, Fisher test, and Cochran-Armitage trend test. Kaplan-Meier curves depicted overall survival (OS), local recurrence-free survival (LRFS), and metastasis-free survival (MFS) rates in the overall study population.

RESULTS

A total of 291 consecutive patients were identified; 111 and 180 patients underwent PRFA and PN, respectively. Median follow-up time was 38 and 48 months, and mean hospitalization days were 1.04 and 3.57 days, respectively. The variables underpinned with high surgical risk were significantly increased in PRFA compared to those in PN (mean age was 64.56 and 57.47 years, the solitary kidney presence was 12.6% and 5.6%, ASA score ≥ 3 was 36% and 14.5%, respectively). The rest of oncological outcomes were comparable amongst PRFA and PN. Patients undergoing PRFA did not improve OS, LRFS, and MFS compared to those undergoing PN. Limitations comprise retrospective design and limited statistical power.

CONCLUSION

PRFA for SMRs in high-risk patients is non-inferior in terms of oncological outcomes and safety compared to PN.

CLINICAL RELEVANCE STATEMENT

Our study has a direct clinical application as it proves that radiofrequency ablation is an effective and uncomplicated therapeutic option for patients with small renal masses.

KEY POINTS

•There are non-inferiority results in overall survival, local recurrence-free survival, and metastasis-free survival between PRFA and PN. •Our two-center study showed that PRFA is non-inferior to PN in oncological outcomes. •Contrast-enhanced power ultrasound-guided PRFA provides an effective therapy for T1 renal tumors.

Contrast-enhanced ultrasound of the kidneys: principles and potential applications

Contrast-enhanced ultrasound (CEUS) is an extension and an enhanced form of ultrasound that allows real-time evaluation of the various structures in different vascular phases. The last decade has witnessed a widespread expansion of CEUS applications beyond the liver. It has shown fair potential in kidneys and its diagnostic efficacy is comparable to CT and MRI. Ultrasound is the well-accepted screening modality for renal pathologies, however, it underperforms in the characterization of the renal masses. CEUS can be beneficial in such cases as it can help in the characterization of such incidental masses in the same sitting. It has an excellent safety profile with no risk of radiation or contract-related nephropathy. It can aid in the correct categorization of renal cysts into one of the Bosniak classes and has proven its worth especially in complex cysts or indeterminate renal masses (especially Bosniak Category IIF and III). Few studies also describe its potential role in solid masses and in differentiating benign from malignant masses. Other areas of interest include infections, infarctions, trauma, follow-up of local ablative procedures, and VUR. Through this review, the readers shall get an insight into the various applications of CEUS in kidneys, with imaging examples.

[What is evidence-based in the treatment of autosomal dominant polycystic kidney disease?]

The cystic transformation of the kidneys and liver are the most common symptoms of autosomal dominant polycystic kidney disease (prevalence 1:400-1:1000). A set of other manifestations can be observed less frequently, such as intracranial aneurysms. End-stage renal disease affects 50% of patients by the age of 70 years. To date, a targeted treatment is only available for patients at risk of rapidly progressive kidney failure. In 2015, the vasopressin receptor antagonist tolvaptan was approved in Germany for slowing down the decline of renal function in autosomal dominant polycystic kidney disease. Selecting the patients that benefit from tolvaptan treatment remains a major challenge. In recent years numerous clinical trials were carried out showing unspecific approaches to slow down the decline in renal function: strictly controlling blood pressure is one of the most important factors. Furthermore, unspecific approaches comprise suppression of vasopressin by sufficient fluid intake and restricted intake of salt. Weight reduction is recommended for obese patients. Lacking more causal approaches, these unspecific measures should be exploited in all patients. Currently, preclinical and clinical trials are testing numerous agents for the establishment of targeted treatment against the cystic degeneration of the kidneys and liver. This also includes dietary approaches. So far, in contrast to other genetic diseases, there are currently no gene therapy approaches for autosomal dominant polycystic kidney disease.

Sarcomatoid renal cell carcinoma with autosomal dominant polycystic kidney disease: a case report and literature review

Diagnosis of renal cell carcinoma (RCC) in patients with autosomal dominant polycystic kidney disease (ADPKD) is challenging and often delayed due to accompanying multiple renal cysts. Sometimes, it is difficult to distinguish RCC from cyst infection or hemorrhage. We herein present the case of a patient with ADPKD undergoing long-term hemodialysis whose sarcomatoid RCC was difficult to diagnose and was confirmed via nephrectomy. A 53-year-old male, undergoing hemodialysis since 20 years for end-stage renal disease secondary to ADPKD, was admitted to our hospital with a 3-week history of fever at > 38 °C and right flank pain. Clinical manifestations were compatible with cyst infection. Magnetic resonance images of the lesion identified in the lower right kidney, revealing slightly high signal intensity on T1-weighted images, low signal intensity on T2 weighted images, and restricted diffusion on diffusion-weighted images, were also consistent with those of cyst infection. Therefore, antibiotic therapy with ciprofloxacin, doripenem, and vancomycin was initiated. However, the patient's symptoms did not improve. Consequently, right nephrectomy was performed for both diagnosis and treatment, which revealed a sarcomatoid RCC with metastasis to the regional lymph node. The patient gradually developed cachexia and died on day 106 post-admission. The present case illustrates the difficulty of diagnosing RCC in patients with ADPKD, particularly sarcomatoid RCC, which is a rare and aggressive variant of RCC, even with the use of various types of imaging modalities. An early decision of nephrectomy may be necessary in such cases.

Utility of Intraprocedural Contrast-Enhanced CT in Ablation of Renal Masses

OBJECTIVE. The purpose of this study was to evaluate the efficacy of radiofrequency ablation (RFA) of renal masses comparing a group who did not undergo intraprocedural CT and a group who did. MATERIALS AND METHODS. A retrospective review included 45 consecutively registered patients who underwent RFA of renal masses. If an adequate biopsy specimen was not obtained or follow-up was inadequate, the patient was eliminated from review from calculation of primary technical efficacy. The inclusion criterion was having undergone RFA with two cooled-tip electrodes. Baseline demographics (age, body mass index, and sex), renal mass characteristics (diameter, side, location, position, morphologic features, type of mass, and grade), technical details (repositioning and hydrodissection), and complications were evaluated. Follow-up images were evaluated to determine the presence of recurrence at the ablation site in the two groups. RESULTS. Among the 45 patients who underwent RFA, 13 did not undergo intraprocedural CT and 32 intraprocedural did. Thirty-five patients met the criteria for follow-up and positive biopsy results. For calculation of recurrence, 10 patients were in the group who did not and 25 were in group who did undergo intraprocedural contrast-enhanced CT. No correlation was found between baseline demographics, renal mass characteristics, and technical results of the two groups. There was an 89% overall technical efficacy rate with a 96% primary technical efficacy rate in the group who underwent intraprocedural CT compared with a 70% rate in the group who did not undergo intraprocedural CT. Negative correlation was found between the groups with respect to technical efficacy rate at p < 0.05. CONCLUSION. Intraprocedural contrast-enhanced CT yields important information about completeness of ablation during the procedure, allowing probe repositioning and thus better therapeutic effect.

Polycystic kidney disease

Cystic kidneys are common causes of end-stage renal disease, both in children and in adults. Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are cilia-related disorders and the two main forms of monogenic cystic kidney diseases. ADPKD is a common disease that mostly presents in adults, whereas ARPKD is a rarer and often more severe form of polycystic kidney disease (PKD) that usually presents perinatally or in early childhood. Cell biological and clinical research approaches have expanded our knowledge of the pathogenesis of ADPKD and ARPKD and revealed some mechanistic overlap between them. A reduced 'dosage' of PKD proteins is thought to disturb cell homeostasis and converging signalling pathways, such as Ca²⁺, cAMP, mechanistic target of rapamycin, WNT, vascular endothelial growth factor and Hippo signalling, and could explain the more severe clinical course in some patients with PKD. Genetic diagnosis might benefit families and improve the clinical management of patients, which might be enhanced even further with emerging therapeutic options. However, many important questions about the pathogenesis of PKD remain. In this Primer, we provide an overview of the current knowledge of PKD and its treatment.

Role of ultrasound in the assessment of percutaneous laser ablation of cervical metastatic lymph nodes from thyroid carcinoma

Background Few studies have examined the feasibility and efficiency of performing ultrasound and contrast-enhanced ultrasound (CEUS) after percutaneous laser ablation (PLA) of cervical metastatic lymph nodes from thyroid cancer. Purpose To investigate and describe the use of conventional ultrasound and CEUS in evaluating PLA of metastatic lymph nodes. Material and Methods PLA was performed in a small, prospective, observational study of 21 metastatic lymph nodes in 17 thyroid cancer patients who underwent radical thyroid resection. CEUS was conducted prior to PLA and 1 h and seven days after ablation. Conventional ultrasound examination of all nodes was performed during follow-up after ablation. We observed contrast agent perfusion in the lymph nodes, calculated perfusion defect volumes using CEUS and determined the rates of reduction for metastatic lymph nodes for a mean duration of 17.86 ± 4.704 months (range = 12-27 months). Results CEUS demonstrated that the perfusion defect volume was larger on day 7 than on day 1 post-ablation in 47% of the ablated nodes. Compared to the largest diameters and volumes pre-PLA, the corresponding post-PLA values significantly decreased ( P < 0.05 versus baseline). No statistically significant change in thyroglobulin (Tg) levels before and after PLA was observed in this study ( P > 0.05 versus baseline). Conclusion CEUS can be effectively used to distinguish the margins of ablated regions, assess the accuracy of PLA, and monitor short-term changes in necrotic areas. However, long-term follow-up assessments of the curative effect of PLA will predominantly rely on conventional ultrasonography.

The safety and efficacy of MPR-CTU combined with precise intraoperative ultrasonography guided flexible ureteroscope in the treatment of renal cystic disease

The safety and efficacy of multi-planar reconstruction (MPR) image post-processing technique-computed tomography (CT) urography (CTU) combined with precise intraoperative ultrasonography guided flexible ureteroscope in renal cyst incision and drainage in the treatment of cystic diseases of kidney were evaluated. A total of 68 patients were randomly divided into control and observation group (n=34). All the patients were treated with renal cyst incision and drainage under flexible ureteroscope. The control group was under ultrasound guidance. The observation group was combined with MPR-CTU, the safety and efficacy was compared. There was no significant difference between the two groups in the success rate and the time of cyst treatment (P>0.05). The incidence of intraoperative and postoperative complications of the observation group was significantly lower than that of the control group. After 1 month follow-up, the total effective rate of the observation group was significantly higher than that of the control group, the difference was statistically significant (P<0.05). Conclusion MPR-CTU technique combined with intraoperative ultrasonography to guide cyst incision and drainage under flexible ureteroscope for renal cystic disease has a high safety and efficacy, and it is worthy of clinical application.

[Percutaneous renal ablation: Pre-, per-, post-interventional evaluation modalities and adapted management]

OBJECTIVES

Ablative treatment (AT) rise is foreseen, validation of steps to insure good proceedings is needed. By looking over the process of the patient, this study evaluates the requirements and choices needed in every step of the management.

METHODS

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

RESULTS

Explanations of AT proposal rather than partial nephrectomy or surveillance have to be discussed in a consultation shared by urologist and interventional radiologist. Per-procedure choices depend on predictable ballistic difficulties. High volume, proximity of the hilum or of a risky organ are in favor of general anesthesia, cryotherapy and computed tomography/magnetic resonance imaging (CT/MRI). Percutaneous approach should be privileged, as it seems as effective as the laparoscopic approach. Early and delayed complications have to be treated both by urologist and radiologist. Surveillance by CT/MRI insure of the lack of contrast-enhanced in the treated area. Patients and tumors criteria, in case of incomplete treatment or recurrence, are the key of the appropriate treatment: surgery, second session of AT, surveillance.

CONCLUSION

AT treatments require patient's comprehension, excellent coordination of the partnership between urologist and radiologist and relevant choices during intervention.

Clinical study of radiofrequency ablation combined with TACE in the treatment of breast cancer with liver metastasis

We studied the clinical effects of percutaneous radiofrequency ablation (RFCA) combined with trans-catheter arterial chemoembolization (TACE) in the treatment of breast cancer with liver metastasis. Eighty-eight patients with a diagnosis of breast cancer with liver metastasis for the first time and patients with liver metastasis after radical mastectomy were consecutively selected. The subjects were divided according to the different treatment methods. They were divided either into the control group of 50 cases or the observation group of 38 cases. Breast cancer patients underwent radical mastectomy with conventional systemic venous chemotherapy. The liver metastasis control group used TACE, while the observation group combined RFCA with TACE. The two groups were followed up for a median time of 20 months, and the clinical effects were compared. The effective rate of the observation group was higher than that of the control group; differences were statistically significant (P<0.05). There was no differences in the incidence of complications between the two groups (P>0.05). The progression free survival, median survival time and survival rate of the observation group were increased; differences were statistically significant (P<0.05). Therefore, RFCA combined with TACE in the treatment of breast cancer with liver metastasis is safe and effective.

Percutaneous radiofrequency ablation for renal cell carcinoma vs. partial nephrectomy: Comparison of long-term oncologic outcomes in both clear cell and non-clear cell of the most common subtype

OBJECTIVES

To compare the clinical outcomes of percutaneous radiofrequency ablation (PRFA) and partial nephrectomy (PN) in patients with clear cell renal cell carcinoma (ccRCC) and non-clear cell RCC (nccRCC) of the most common subtypes.

MATERIALS AND METHODS

A retrospective study was conducted to review the records of all the patients who underwent PRFA or PN between February 2005 and April 2014 at our institution. Patients with histologic confirmation of ccRCC, papillary RCC, and chromophobe RCC were included. The Mann-Whitney U test was applied to compare PRFA to PN in the ccRCC and nccRCC groups. The Kaplan-Meier method was used to generate the survival curves that were compared to the log-rank test.

RESULTS

A total of 264 patients meeting the selection criteria were included in this study. The tumor size ranged from 0.9 to 7.0cm. The median follow-up period was 78 months (range: 8-132 mo). Although PRFA provided comparable 10-year overall survival rates and 10-year disease-free survival (DFS) rates to PN both in ccRCC ≤4cm and nccRCC, the 10-year DFS for patients treated with PRFA was lower than that of PN in ccRCC >4cm. The DFS survival curve between the 2 operations and 2 subtypes was statistically significant in patients with tumor size >4cm. Limitations include retrospective review and selection bias.

CONCLUSIONS

Patients with T1b ccRCC treated with PRFA have less favorable outcomes than those with PN whereas PRFA provides comparable oncologic outcomes to PN in patients with T1b nccRCC. It is necessary to take RCC subtypes into consideration when choosing a surgical approach to treat T1b RCC between PFRA and PN.

Diagnostic accuracy of contrast-enhanced computed tomography and contrast-enhanced magnetic resonance imaging of small renal masses in real practice: sensitivity and specificity according to subjective radiologic interpretation

Background

The aim of this study was to investigate the diagnostic accuracy of contrast-enhanced computed tomography (CT) and contrast-enhanced magnetic resonance imaging (MRI) of small renal masses in real practice.

Methods

Contrast-enhanced CT and MRI were performed between February 2008 and February 2013 on 68 patients who had suspected small (≤4 cm) renal cell carcinoma (RCC) based on ultrasonographic measurements. CT and MRI radiographs were reviewed, and the findings of small renal masses were re-categorized into five dichotomized scales by the same two radiologists who had interpreted the original images. Receiver operating characteristics curve analysis was performed, and sensitivity and specificity were determined.

Results

Among the 68 patients, 60 (88.2 %) had RCC and eight had benign disease. The diagnostic accuracy rates of contrast-enhanced CT and MRI were 79.41 and 88.23 %, respectively. Diagnostic accuracy was greater when using contrast-enhanced MRI because too many masses (67.6 %) were characterized as “4 (probably solid cancer) or 5 (definitely solid cancer).” The sensitivity of contrast-enhanced CT and MRI for predicting RCC were 79.7 and 88.1 %, respectively. The specificities of contrast-enhanced CT and MRI for predicting RCC were 44.4 and 33.3 %, respectively. Fourteen diagnoses (20.5 %) were missed or inconsistent compared with the final pathological diagnoses. One appropriate nephroureterectomy and five unnecessary percutaneous biopsies were performed for RCC. Seven unnecessary partial nephrectomies were performed for benign disease.

Conclusions

Although contrast-enhanced CT and MRI showed high sensitivity for detecting small renal masses, specificity remained low.