The Past, Present, and Future in Management of Small Renal Masses. J Oncol. 2015;2015:364807. [PMID: 26491445 PMCID: PMC4605375 DOI: 10.1155/2015/364807]

Diagnostic Value of Contrast-Enhanced Ultrasound in Differentiating Malignant from Benign Small Renal Masses After CT/MRI

Background: The aim of this study was to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) in characterizing small renal masses (SRMs) measuring less than 3 cm and in distinguishing between malignant and benign SRMs. Methods: A retrospective study was conducted between January 2022 and January 2023 at the Radiology Department of (Anonymized data), with a total of 43 patients assessed via CT and MRI scans, which were subsequently studied by experienced radiologists who were blinded to the pathology results. The CEUS findings were then compared with histopathological examination outcomes or follow-up imaging results. Results: The study results revealed a notably high level of diagnostic accuracy, with sensitivity at 0.875, specificity at 0.94, positive predictive value at 0.95, and negative predictive value at 0.86 for characterizing SRMs. Spearman rank correlation analysis substantiated a robust positive linear correlation between the CEUS findings and biopsy results (r = 0.972). Conclusions: These findings underscore the potential utility of CEUS as a valuable tool for discriminating between malignant and benign SRMs, carrying significant implications for clinical decision-making and leading to improved patient outcomes. However, larger validation studies are imperative to establish its role in routine clinical practice and to address potential limitations.

The long-term outcomes of local tumor destruction versus partial nephrectomy for cT1a non-clear cell renal cell carcinoma and development of prognostic nomograms

PURPOSE

There is a lack of authoritative opinions on local tumor destruction (LTD) for clinical T1a (cT1a) non-clear cell renal cell carcinoma (nccRCC). We aim to compare the outcomes of cT1a nccRCC after partial nephrectomy (PN) or LTD and explore prognostic factors.

METHODS

Patients diagnosed with cT1a nccRCC receiving LTD or PN between 2000 and 2020 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. A 1:1 propensity score matching (PSM) was performed for patients receiving LTD and PN. Kaplan-Meier survival analysis, Cox regression analysis, competing risk regression models, and subgroup analysis were used to compare outcomes and identify prognostic factors. Prognostic nomograms were established and evaluated based on the multivariate models.

RESULTS

A total of 3664 cT1a nccRCC patients were included. The LTD group had poorer overall survival (OS) and similar cancer-specific survival (CSS) compared with the PN group before and after PSM (p < 0.05), while the other-cause mortality rate of the LTD group was higher than that of the PN group. Age, marital status, household income, prior tumor history, interval between diagnosis and treatment, treatments, and tumor size were identified as independent predictive factors for OS. Age, tumor size, prior tumor history, and histological type were identified as independent predictive factors for CSS. Then the nomograms predicting OS and CSS were constructed based on these prognostic factors, which showed excellent performance in risk stratification and accuracy.

CONCLUSION

LTD could achieve comparable cancer-control effects as PN among cT1a nccRCC patients. The OS and CSS nomograms worked effectively for prognosis assessment.

Survival pattern of metastatic renal cell carcinoma patients according to WHO/ISUP grade: a long-term multi-institutional study

The World Health Organization/International Society of Urological Pathology (WHO/ISUP) grading of renal cell carcinoma (RCC) is classified from grade 1-4, regardless of subtype. The National Comprehensive Cancer Network (NCCN) guidelines (2022) state that if there is an adverse pathological feature, such as grade 3 or higher RCC in stage 1 patients, more rigorous follow-up imaging is recommended. However, the RCC guidelines do not provide specific treatment or follow-up policies by tumor grade. Therefore, this study attempted to find out whether tumor grade affects survival rates in patients with metastatic RCC. The Korean Renal Cancer Study Group (KRoCS) database includes 3108 patients diagnosed with metastatic RCC between September 1992 and February 2017, with treatment methods, progression, and survival data collected from 11 tertiary hospitals. To obtain information on survival rates or causes of death, we utilized the Korea National Statistical Office database and institutional medical records. Data were accessed for research purpose on June, 2023. We then reviewed these sources to gather comprehensive and reliable data on the outcomes of our study cohort. This database was retrospectively analyzed, and out of 3108 metastatic RCC patients, 911 had been identified as WHO/ISUP grade. Grades were classified into either a low-grade (WHO/ISUP grade 1-2) or a high-grade group (WHO/ISUP grade 3-4). The patients were then analyzed related to progression and overall survival (OS). In metastatic clear cell RCC patients, the 1-year OS rate was 69.4% and the median OS was 17.0 months (15.5-18.5) followed up to 203.6 months. When comparing the patient groups, 119 low-grade and 873 high-grade cases were identified. No baseline difference was observed between the two groups, except that the high-grade group had a higher ECOG 1 ratio of 50.4% compared with 34.5% for the low-grade group (p = 0.009). There was a significant difference in OS between high-grade and low-grade groups. OS was 16.0 months (14.6-17.4) in the high-grade group and 28.0 months (21.1-34.9) in the low-grade group (p < 0.001). However, there was no difference in progression-free survival (PFS) rates with 9.0 months (8.0-10.0) for the high-grade group and 10.0 months (6.8-13.2) for the low-grade group (p = 0.377) in first-line treatment. In multivariable analysis, WHO/ISUP grade was a risk factor (HR = 1.511[1.135-2.013], p = 0.005) that influenced the OS. In conclusion, WHO/ISUP grade is a major data source that can be used as a ubiquitous marker of metastatic RCC in pre-IO era. Depending on whether the RCC is high or low grade, the follow-up schedule will need to be tailored according to grade, with higher-grade patients needing more active treatment as it can not only affect the OS in the previously known localized/locoregional recurrence but also the metastatic RCC patient.

Scientific Status Quo of Small Renal Lesions: Diagnostic Assessment and Radiomics

Background: Small renal masses (SRMs) are defined as contrast-enhanced renal lesions less than or equal to 4 cm in maximal diameter, which can be compatible with stage T1a renal cell carcinomas (RCCs). Currently, 50-61% of all renal tumors are found incidentally. Methods: The characteristics of the lesion influence the choice of the type of management, which include several methods SRM of management, including nephrectomy, partial nephrectomy, ablation, observation, and also stereotactic body radiotherapy. Typical imaging methods available for differentiating benign from malignant renal lesions include ultrasound (US), contrast-enhanced ultrasound (CEUS), computed tomography (CT), and magnetic resonance imaging (MRI). Results: Although ultrasound is the first imaging technique used to detect small renal lesions, it has several limitations. CT is the main and most widely used imaging technique for SRM characterization. The main advantages of MRI compared to CT are the better contrast resolution and tissue characterization, the use of functional imaging sequences, the possibility of performing the examination in patients allergic to iodine-containing contrast medium, and the absence of exposure to ionizing radiation. For a correct evaluation during imaging follow-up, it is necessary to use a reliable method for the assessment of renal lesions, represented by the Bosniak classification system. This classification was initially developed based on contrast-enhanced CT imaging findings, and the 2019 revision proposed the inclusion of MRI features; however, the latest classification has not yet received widespread validation. Conclusions: The use of radiomics in the evaluation of renal masses is an emerging and increasingly central field with several applications such as characterizing renal masses, distinguishing RCC subtypes, monitoring response to targeted therapeutic agents, and prognosis in a metastatic context.

Real world outcomes of biopsy-proven oncocytic neoplasm of the kidney managed by surveillance

Objectives

To evaluate outcomes of patients diagnosed with oncocytic renal neoplasms on routine renal mass biopsy and to describe the natural history of these tumours when managed with surveillance as opposed to immediate intervention. To report disease-specific survival.

Patients and methods

Patients were identified from a retrospective review of pathology databases from three tertiary referral centres that utilise renal mass biopsy in routine clinical practice. All patients with biopsy-proven oncocytic tumours were included and a retrospective review of online patient records was undertaken.

Results

There were 184 biopsy-proven oncocytic renal neoplasms identified in 172 patients. There were two biopsy complications (both pneumothorax, Clavien-Dindo Grade I). Of these lesions, 135 were reported as oncocytomas or oncocytic renal neoplasms that were not further classified and 37 were reported as chromophobe carcinoma (ChRCC). The median age at diagnosis was 70 (33-88). The average tumour diameter at diagnosis was 33 mm. One hundred seven tumours were initially managed with surveillance (including 13 ChRCC) with a minimum follow-up of 6 months and a median of 39 months (6-144) whereas 49 patients underwent immediate treatment. The mean growth rate across all oncocytic renal neoplasms managed by surveillance was 3 mm/year. There was no statistically significant difference in growth rates between oncocytic renal neoplasms and ChRCC. Thirteen patients with oncocytic renal neoplasms initially managed by surveillance moved on to an active management strategy during follow-up. The clinical indication given for a change from surveillance was tumour growth in 12 cases and patient choice in 1 case. Where definitive pathology was available, there was 85% concordance with the biopsy. There were no cases of development of metastatic disease or disease-related morbidity or mortality during the study.

Conclusions

This multicentre retrospective cohort study supports the hypothesis that selected biopsy-proven oncocytic renal neoplasms can be safely managed with surveillance in the medium term. Routine renal mass biopsy may reduce surgery for benign or indolent renal tumours and the potential associated morbidity for these patients.

The impact of a multidisciplinary small renal mass clinic on patient treatment decisions

INTRODUCTION

Small renal masses (SRMs) are managed with active surveillance (AS), thermal ablation (TA), irreversible electroporation (IRE), or surgery, depending on patient and tumor factors. A novel SRM multidisciplinary clinic (SRMC), involving urologists and interventional radiologists, was established to provide patients with information on treatments options. The objective of this study was to evaluate the impact of the SRMC on treatment decision-making METHODS: Demographics, tumor characteristics, and treatment decisions were prospectively collected on patients (n=216) attending the SRMC between 2016 and 2019. A retrospective historic cohort (n=238) seen by urologists was used as a control group. Key variables were analyzed and compared. Patient satisfaction (n=27) was surveyed and responses were summarized and explored.

RESULTS

Mean age, tumor size, and pathology was similar between groups; however, the SRMC cohort had more male patients (65.7% vs. 53.8%, p=0.009). Chosen treatment modality differed significantly between cohorts (p<0.0001). Patients in the historic cohort were treated by AS (41.5%), surgery (37.9%), TA (11.9%), watchful waiting (7.9%), and IRE (0.8%). SRMC patients were treated by TA (42.2%), AS (26.7%), surgery (21.3%), IRE (7.6%), and watchful waiting (2.2%). Post-hoc analysis revealed statistically significant differences in proportions of AS, TA, IRE, and surgery between cohorts. Patients reported high satisfaction with the collaborative approach.

CONCLUSIONS

A multidisciplinary approach may have an impact on patient treatment decision-making for SRMs. Consultations involving a urologist and an interventional radiologist resulted in more TA and IRE and less AS and surgery. Future studies should evaluate if these findings occur in other centers.

Development of the clinical calculator for mortality of patients with metastatic clear cell type renal cell carcinoma: An analysis of patients from Korean Renal Cancer Study Group database

Purpose

To develop the clinical calculator for mortality of patients with metastatic renal cell carcinoma (mRCC) using Korean Renal Cancer Study Group (KRoCS) database.

Materials and Methods

Data from 1,115 patients with mRCC treated in 4 hospitals joining KRoCS between 1993 and 2016 were pooled. Five-year survival rates were calculated using Kaplan–Meier curve. A clinical calculator for 5-year mortality was developed using multivariable logistic regression analysis and validated externally using dataset including 916 patients from 4 other hospitals.

Results

Overall survival rates and cancer specific survival rate at 5 years were 28.5% and 29.4%, respectively. Among baseline factors, increased neutrophil-lymphocyte ratio (≥4), synchronous metastasis, low albumin (<3.0 g/dL), and low hemoglobin (<lower limit of normal: male, 13 g/dL; female, 11.5 g/dL) were the significant factors in 5-year mortality. Good internal validity was demonstrated with area under the curve estimates being 0.774 at 5-year mortality calculation and the calibration plot. In the external validation, 758 (82.8%) died by 5 years among these patients, with the average model-predicted rate of 72.9%.

Conclusions

A clinical calculator has been developed to quantify the risk of death for individual patients after treatment of mRCC. This tool may be useful for patients or their guardians who want to know their prognosis and to identify patients requiring aggressive therapy and additional supportive measures during and after treatment.

Current management of small renal masses

One of the consequences of the growing use of diagnostic imaging techniques is the notable growth in the detection of small renal masses presumably corresponding to localized tumors that are potentially curable with surgical treatment. When faced with the finding of a small renal mass, radiologists must determine whether it is benign or malignant, and if it is malignant, what subtype it belong to, and whether it should be managed with surgical treatment, with ablative techniques, or with watchful waiting with active surveillance. Small renal masses are now a clinical entity that require management different from the approaches used for classical renal cell carcinomas. In this scenario, radiologists are key because they are involved in all aspects of the management of these tumors, including in their diagnosis, treatment, and follow-up.

The value of surveying the kidneys during pelvic ultrasound examinations

INTRODUCTION

Pelvic ultrasounds are commonly performed for various clinical indications in female patients presenting to the hospital. A survey of the kidneys is routinely included as part of the examination, but there is limited justification for their inclusion in the assessment of every female presenting for a pelvic ultrasound.

METHOD

We examined the utility of surveying the kidney ultrasound during pelvic ultrasonography by reviewing the records of 1009 pelvic ultrasound examinations in 1000 women.

RESULTS

In total, 46 incidental findings were identified, but 91% of these were clinically inconsequential. Only four patients had incidental findings of high clinical priority requiring specialist treatment. Of these, two patients were symptomatic and had urinary tract obstruction due to stones. The other two patients harboured asymptomatic renal cell carcinomas. The overall incidence of renal incidental findings of high clinical priority in asymptomatic patients was two in 1009 examinations (1999 kidneys).

CONCLUSION

Indiscriminate uncritical screening of the kidneys in women presenting for pelvic ultrasound is not evidence-based and represents a low-yield examination with extremely low rate of incidental findings of clinical significance.

Percutaneous irreversible electroporation for the treatment of small renal masses: The first Canadian case series

INTRODUCTION

Irreversible electroporation (IRE) is a novel technology used in the minimally invasive treatment of small solid organ tumours. Currently, there is a paucity of literature studying treatment of small renal masses (SRMs) with IRE. Our pilot study is the first case series in Canada to use IRE in the treatment of SRMs.

METHODS

This retrospective cohort pilot study includes five patients (three females and two males) who presented with a SRM that was deemed not amendable to any other treatment than a radical nephrectomy or IRE. The IRE procedures were carried out by an interventional radiologist in conjunction with a urologist using the Angiodynamics NanoKnife IRE device.

RESULTS

Mean tumour size was 28 mm (range 18-39), with a mean R.E.N.A.L. nephrometry score of 8.4±0.55. Over a mean followup of 22.8 months (range 14-31), four out of the five patients did not have a radiological recurrence. No adverse events were reported after the five IRE procedures. Renal function was stable post-IRE, with no to negligible decreases in estimated glomerular filtration rate detected (range +2 to -13 mL/min/1.73 m²).

CONCLUSIONS

Our pilot study demonstrates that renal percutaneous IRE is safe to use in the context of challenging-to-treat SRMs. Early radiological and renal function outcomes are encouraging, but further study is required to assess oncological success. The small sample size, retrospective nature of the study, relatively short followup, and the lack of routine renal biopsy to confirm malignancy are the major limitations noted.

Quantitative multiparametric MR analysis of small renal lesions: correlation with surgical pathology

PURPOSE

The purpose of the study is to evaluate the utility of apparent diffusion coefficient (ADC), chemical shift signal intensity index (SII), and contrast enhancement in distinguishing between benign lesions and renal cell carcinoma (RCC) and between subtypes of renal lesions.

METHODS

This retrospective study included 98 renal lesions (≤ 3 cm) on MRI with correlative surgical pathology. Scanner field strength, lesion location, and size were recorded. Two readers blinded to surgical pathology independently measured ADC ratio (ADC lesion/ADC non-lesion kidney), SII, and absolute/relative enhancement in the corticomedullary and nephrographic phases of contrast.

RESULTS

There were 76 malignant and 22 benign lesions. 42 RCC were clear cell (ccRCC), 19 papillary (pRCC), 5 chromophobe (cbRCC). Benign lesions included both solid and cystic lesions. Interreader agreement for all variables was good-excellent (ICC 0.70-0.91). There was no difference in ADC or SII between benign and malignant lesions. There was greater absolute corticomedullary enhancement of benign versus malignant lesions (150.0 ± 111.5 vs. 81.1 ± 74.8, p = 0.0115), which did not persist when excluding pRCC. For lesion subtype differentiation, ADC_ratio for pRCC was lower than benign lesions (0.74 ± 0.35 vs. 1.03 ± 0.46, p = 0.0246). ccRCC demonstrated greater SII than other RCC (0.09 ± 0.22 vs. 0.001 ± 0.26, p = 0.0412). Oncocytomas and angiomyolipoma (AML) showed greater absolute corticomedullary enhancement than ccRCC and pRCC (145.6 ± 65.2 vs. 107.2 ± 85.3, p = 0.043 and 186.2 ± 93.9 vs. 37.6 ± 35.3, p = 0.0108), respectively.

CONCLUSIONS

While corticomedullary-phase enhancement was a differentiating feature, quantitative metrics from diffusion and chemical shift imaging cannot reliably differentiate benign from malignant lesions. Quantitative assessment may be useful in differentiating some benign and malignant lesion subtypes.

Global and Targeted miRNA Expression Profiling in Clear Cell Renal Cell Carcinoma Tissues Potentially Links miR-155-5p and miR-210-3p to both Tumorigenesis and Recurrence

About 30% of patients undergoing nephrectomy for renal cell carcinoma (RCC) experience disease recurrence. We profiled miRNAs dysregulated in clear-cell (cc) RCC tumor tissues and predictive of recurrence. The expression levels of 800 miRNAs were assessed in paired tumor and normal tissues from a discovery cohort of 18 ccRCC patients. miRNAs found to be differentially expressed were examined in a validation set of 205 patients, using real-time quantitative PCR. Tumor-normal data from 64 patients in The Cancer Genome Atlas were used for external validation. Twenty-eight miRNAs were consistently dysregulated in tumor tissues. On dichotomized analysis, patients with high levels of miR-155-5p and miR-210-3p displayed an increased risk for ccRCC recurrence (hazard ratio, 2.64; 95% CI, 1.49 to 4.70; P = 0.0009; and hazard ratio, 1.80; 95% CI, 1.04 to 3.12; P = 0.036, respectively) and a shorter median recurrence-free survival time than did patients with low levels [P < 0.01 (log rank test)]. A risk score was generated based on the expression levels of miR-155-5p and miR-210-3p, and the trend test was significant (P = 0.005). On pathway analysis, target genes regulated by miR-155-5p and miR-210-3p were mainly enriched in inflammation-related pathways. We identified and validated multiple miRNAs dysregulated in ccRCC tissues; miR-155-5p and miR-210-3p were predictive of ccRCC recurrence, pointing to potential utility as biomarkers and underlying biological mechanisms.

Changeable Conditional Survival Rates and Associated Prognosticators in Patients with Metastatic Renal Cell Carcinoma Receiving First Line Targeted Therapy

PURPOSE

In this study we evaluated conditional survival probabilities in patients with metastatic renal cell carcinoma who underwent first line tyrosine kinase inhibitor therapy. We also identified predictors of conditional survival with time.

MATERIALS AND METHODS

We retrospectively reviewed clinical data on 1,659 individuals with metastatic renal cell carcinoma in the Korean Renal Cancer Study Group database, of whom the records of 1,131 were finally analyzed. The primary end point was conditional overall survival. Kaplan-Meier survival analysis was used to calculate conditional overall survival probabilities using the formula, conditional survival (α│β) = S(α + β)/S(β), indicating the likelihood of additional α years survivorship in person who has already survived for β years after initial therapy. S(χ) represents the actual survival rate. Multivariate Cox regression model was used to identify predictors of conditional survival with time.

RESULTS

Six, 12, 18, 24 and 36-month conditional overall survival gradually increased in patients at all additional survival times after initial treatment compared to patient baseline survival estimations. While the actual overall survival rate decreased with time, the 36-month conditional overall survival rate was calculated as 7.3% higher in patients who had already survived 36 months compared to baseline estimations at the time of initial tyrosine kinase inhibitor treatment. Furthermore, predictors of conditional overall survival changed with time. Only previous metastasectomy remained a key prognosticator of conditional overall survival until 36 months of survival following initial tyrosine kinase inhibitor treatment.

CONCLUSIONS

Conditional survival improved with time after initial tyrosine kinase inhibitor treatment in patients with metastatic renal cell carcinoma. Our study offers valuable information for practical survival estimations and relevant prognosticators in patients with metastatic renal cell carcinoma who receive first line tyrosine kinase inhibitor.

Ultrasound-guided percutaneous radiofrequency ablation for treating small renal masses

INTRODUCTION

The objective of this study was to analyse and assess the experience with radiofrequency ablation of small renal masses using a contrast-enhanced, ultrasound-guided percutaneous approach for patients who are not suitable for surgical resection and/or who refused surveillance or observation.

MATERIAL AND METHOD

From January 2007 to August 2015, 164 treatments were performed on a total of 148 patients. We present the patients' clinical-radiological characteristics, oncological and functional results in the short and medium term.

RESULTS

The overall technical success rate was 97.5%, with a successful outcome in 1 session in 100% of the lesions≤3cm and 92% in lesions measuring 3-5cm. The mean tumour diameter in the patients for whom the treatment was ultimately successful was 2.7cm, while the mean diameter of these in the unsuccessful operations was 3.9cm (P<.05). There were no statistically significant differences in the serum creatinine levels and estimated glomerular filtration rates.

CONCLUSIONS

Despite the low rate of positive renal biopsies in the series, ultrasound-guided percutaneous radiofrequency ablation for treating small renal lesions appears to be an effective and safe procedure with a minimum impact on renal function, an acceptable oncologic control in the short and medium term and a low rate of complications.

Percutaneous biopsy of the renal mass: FNA or core needle biopsy?

BACKGROUND

In recent years, there have been increasing indications for percutaneous renal biopsy. Fine-needle aspiration (FNA), with or without core needle biopsy (CB), has been used increasingly in the management of renal tumors at the study institution.

METHODS

A computerized search of laboratory records was conducted to retrieve FNA cases of renal masses as well as the correlating CB and/or nephrectomy specimens. The cases spanned a period of 10 years (2006-2015). The diagnoses were classified into 5 categories: malignant, suspicious for malignancy, neoplastic, atypical, and negative/nondiagnostic. Based on the results of the nephrectomy specimens, the diagnostic rate, sensitivity, and diagnostic accuracy were calculated among 3 groups of specimens: FNA only, CB only, and combined FNA and CB.

RESULTS

A total of 247 cases of FNA with 123 correlating CB and 101 follow-up nephrectomy specimens were identified. The diagnostic rate, sensitivity, and diagnostic accuracy were 72%, 78%, and 96%, respectively, for FNA; 87%, 92%, and 94%, respectively, for CB; and 92%, 92%, and 94%, respectively, for the combined FNA and CB group. Renal cell carcinoma and its variants were the most common histologic diagnoses (112 of 174 cases; 64%). Significant diagnostic discrepancy was noted in one case: a malignant melanoma that was misdiagnosed as renal cell carcinoma in both the preoperative FNA specimen and in the CB specimen.

CONCLUSIONS

In the current study, both FNA and CB demonstrated excellent diagnostic accuracy (96% and 94%, respectively). The combination of FNA and CB was found to significantly improve the diagnostic rate when compared with either FNA alone (92% vs 72%; P<.05) or CB alone (92% vs 87%). Cancer Cytopathol 2017;125:407-15. © 2017 American Cancer Society.

Magnetic Resonance Imaging and the Use in Small Renal Masses

The incidence of small renal masses (SRM) has been increasing, and this is mainly attributed to the incidental finding of such masses on imaging performed in asymptomatic patients. Consequently, this calls for careful evaluation and management of these masses to determine their nature and need for treatment. This article reviews current literature regarding the evaluation and management of SRM. It focuses on the specific use of MRI in the diagnosis and management of SRM. A Medline review of the literature was performed from 1996 to the present time. Computed tomography (CT) imaging has been the investigation of choice for evaluating SRM. However, some remain difficult to determine their malignant or benign nature and remain indeterminate. In such cases, further imaging with magnetic resonance imaging (MRI) can be performed to evaluate the mass in more detail. It can also be used where CT is contraindicated and where active surveillance is the treatment of choice and radiation exposure is a concern. MRI is a useful tool in evaluating an indeterminate small renal mass. Accurate diagnosis and management of SRM require close collaboration between a urologist and radiologist to identify potentially malignant tumours to subsequently reduce mortality from renal cell cancer.

Kidney function outcomes following thermal ablation of small renal masses

The diagnosis of small renal masses (SRMs) continues to increase likely attributable to widespread use of axial cross-sectional imaging. Many of these SRMs present in elderly patients with abnormal baseline renal function. Such patients are at risk for further decline following therapeutic intervention. Renal thermal ablation presents one approach for management of SRMs whereby tumors are treated in situ without need for global renal ischemia. These treatment characteristics contribute to favorable renal function outcomes following kidney tumor ablation particularly in patients with an anatomic or functional solitary renal unit.