The natural history and predictors for intervention in patients with small renal mass undergoing active surveillance. Adv Urol. 2015;2015:692014. [PMID: 25960742 PMCID: PMC4413980 DOI: 10.1155/2015/692014]

A Randomized Trial of Stereotactic Body Radiation Therapy vs Radiofrequency Ablation for the Treatment of Small Renal Masses: A Feasibility Study (RADSTER)

OBJECTIVE

To evaluate the feasibility of a trial comparing stereotactic beam radiation therapy (SBRT) and radiofrequency ablation (RFA) for small renal masses (SRM).

METHODS

Patients opting for treatment of a SRM at a single center were randomized 1:1 to SBRT or RFA. Crossover if ineligible for treatment after randomization was allowed. Biopsies were completed prior to randomization and 12 months post-treatment. Our primary outcome was feasibility of the trial design. Secondary outcomes included treatment efficacy and safety.

RESULTS

Over 18 months, 33 patients were screened resulting in the recruitment and randomization of 24 patients (SBRT = 12; RFA = 12). Fourteen received SBRT, 7 RFA, and 3 dropped out. Crossover occurred from RFA to SBRT due to inability to perform RFA. Mean estimated glomerular filtration rate (EGFR) reduction was similar at 1 year (RFA -3 ml/minutes/1.73 m2, SBRT -5.3 ml/minutes/1.73 m2, P = .7). One-year biopsies were performed in 95.2% (20/21) of patients receiving treatment. Per protocol analysis demonstrated a higher pathologic response (RFA 100% vs SBRT 33.3.%, P = .01) in patients undergoing RFA compared to SBRT but not in the intention to treat analysis. No patients developed local failure, metastasis or death during the study period.

CONCLUSION

Recruitment, randomization, and follow-up of patients with SRMs was feasible and our results support performing a larger randomized trial. Multidisciplinary evaluation of patients before randomization is needed to assess RFA feasibility to reduce crossover. Both treatments have excellent short-term safety profiles. While not a surrogate for clinical response, RFA had a non-statistically significant improvement in pathological response.

CLINICALTRIALS

gov: NCT03811665.

International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024

The "International Society for Heart and Lung Transplantation Guidelines for the Evaluation and Care of Cardiac Transplant Candidates-2024" updates and replaces the "Listing Criteria for Heart Transplantation: International Society for Heart and Lung Transplantation Guidelines for the Care of Cardiac Transplant Candidates-2006" and the "2016 International Society for Heart Lung Transplantation Listing Criteria for Heart Transplantation: A 10-year Update." The document aims to provide tools to help integrate the numerous variables involved in evaluating patients for transplantation, emphasizing updating the collaborative treatment while waiting for a transplant. There have been significant practice-changing developments in the care of heart transplant recipients since the publication of the International Society for Heart and Lung Transplantation (ISHLT) guidelines in 2006 and the 10-year update in 2016. The changes pertain to 3 aspects of heart transplantation: (1) patient selection criteria, (2) care of selected patient populations, and (3) durable mechanical support. To address these issues, 3 task forces were assembled. Each task force was cochaired by a pediatric heart transplant physician with the specific mandate to highlight issues unique to the pediatric heart transplant population and ensure their adequate representation. This guideline was harmonized with other ISHLT guidelines published through November 2023. The 2024 ISHLT guidelines for the evaluation and care of cardiac transplant candidates provide recommendations based on contemporary scientific evidence and patient management flow diagrams. The American College of Cardiology and American Heart Association modular knowledge chunk format has been implemented, allowing guideline information to be grouped into discrete packages (or modules) of information on a disease-specific topic or management issue. Aiming to improve the quality of care for heart transplant candidates, the recommendations present an evidence-based approach.

Surveillance for low-risk kidney cancer: a narrative review of contemporary worldwide practices

The management trend of low-risk kidney cancer over the last decade has been from treatment with radical nephrectomy, to use of nephron sparing procedures of partial nephrectomy and ablation, as well as the option of active surveillance (AS). This narrative review aims to summarise the available guidelines related to AS and review the published descriptions of regional practices on the management of low-risk kidney cancer worldwide. A search of PubMed, Google Scholar and Cochrane Library databases for studies published 2010 to June 2020 identified 15 studies, performed between 2000 and 2019, which investigated 13 different cohorts of low-risk kidney cancer patients on AS. Although international guidelines show a level of agreement in their recommendation on how AS is conducted, in terms of patient selection, surveillance strategy and triggers for intervention, cohort studies show distinct differences in worldwide practice of AS. Prospective studies showed general agreement in their predefined selection criteria for entry into AS. Retrospective studies showed that patients who were older, with greater comorbidities, worse performance status and smaller tumours were more likely to be managed with AS. The rate of percutaneous renal mass biopsy varied between studies from 2% to 56%. The surveillance protocol was different across all studies in terms of recommended modality and frequency of imaging. Of the 6 studies which had set indications for intervention, these were broadly in agreement. Despite clear criteria for intervention, patient or surgeon preference was still the reason in 11–71% of cases of delayed intervention across 5 studies. This review shows that AS is being applied in a variety of centres worldwide and that key areas of patient selection criteria and surveillance strategy have large similarities. However, the rate of renal mass biopsy and of delayed intervention varies significantly between studies, suggesting the process of diagnosing malignant SRM and decision making whilst on AS are varying in practice. Further research is needed on the diagnosis and characterisation of incidentally found small renal masses (SRM), using imaging and histology, and the natural history of these SRM in order to develop evidence-based active surveillance protocols.

Pretransplant solid organ malignancy and organ transplant candidacy: A consensus expert opinion statement

Patients undergoing evaluation for solid organ transplantation (SOT) often have a history of malignancy. Although the cancer has been treated in these patients, the benefits of transplantation need to be balanced against the risk of tumor recurrence, especially in the setting of immunosuppression. Prior guidelines of when to transplant patients with a prior treated malignancy do not take in to account current staging, disease biology, or advances in cancer treatments. To develop contemporary recommendations, the American Society of Transplantation held a consensus workshop to perform a comprehensive review of current literature regarding cancer therapies, cancer stage-specific prognosis, the kinetics of cancer recurrence, and the limited data on the effects of immunosuppression on cancer-specific outcomes. This document contains prognosis based on contemporary treatment and transplant recommendations for breast, colorectal, anal, urological, gynecological, and nonsmall cell lung cancers. This conference and consensus documents aim to provide recommendations to assist in the evaluation of patients for SOT given a history of a pretransplant malignancy.

Characterization of clear cell renal cell carcinoma and other renal tumors: evaluation of dual-energy CT using material-specific iodine and fat imaging

OBJECTIVE

This study aimed to assess material-specific iodine and fat images for diagnosis of clear cell renal cell carcinoma (cc-RCC) compared to papillary RCC (p-RCC) and other renal masses.

MATERIALS AND METHODS

With IRB approval, we identified histologically confirmed solid renal masses that underwent rapid-kVp-switch DECT between 2016 and 2018: 25 cc-RCC (7 low grade versus 18 high grade), 11 p-RCC, and 6 other tumors (2 clear cell papillary RCC, 2 chromophobe RCC, 1 oncocytoma, 1 renal angiomyomatous tumor). A blinded radiologist measured iodine and fat concentration on material-specific iodine-water and fat-water basis pair images. Comparisons were performed between groups using univariate analysis and diagnostic accuracy calculated by ROC.

RESULTS

Iodine concentration was higher in cc-RCC (6.14 ± 1.79 mg/mL) compared to p-RCC (1.40 ± 0.54 mg/mL, p < 0.001), but not compared to other tumors (5.0 ± 2.2 mg/mL, p = 0.370). Intratumoral fat was seen in 36.0% (9/25) cc-RCC (309.6 ± 234.3 mg/mL [71.1-762.3 ng/mL]), 9.1% (1/11) papillary RCC (97.11 mg/mL), and no other tumors (p = 0.036). Iodine concentration ≥ 3.99 mg/mL achieved AUC and sensitivity/specificity of 0.88 (CI 0.76-1.00) and 92.31%/82.40% to diagnose cc-RCC. To diagnose p-RCC, iodine concentration ≤ 2.5 mg/mL achieved AUC and sensitivity/specificity of 0.99 (0.98-1.00) and 100%/100%. The presence of intratumoral fat had AUC 0.64 (CI 0.53-0.75) and sensitivity/specificity of 34.6%/93.8% to diagnose cc-RCC. A logistic regression model combining iodine concentration and presence of fat increased AUC to 0.91 (CI 0.81-1.0) with sensitivity/specificity of 80.8%/93.8% to diagnose cc-RCC.

CONCLUSION

Iodine concentration values are highly accurate to differentiate clear cell RCC from papillary RCC; however, they overlap with other tumors. Fat-specific images may improve differentiation of clear cell RCC from other avidly enhancing tumors.

KEY POINTS

• Clear cell renal cell carcinoma (RCC) has significantly higher iodine concentration than papillary RCC, but there is an overlap in values comparing clear cell RCC to other renal tumors. • Iodine concentration ≤ 2.5 mg/mL is highly accurate to differentiate papillary RCC from clear cell RCC and other renal tumors. • The presence of microscopic fat on material-specific fat images was specific for clear cell RCC, helping to differentiate clear cell RCC from other avidly enhancing renal tumors.

Renal Cell Carcinoma: Alternative Nephron-Sparing Treatment Options for Small Renal Masses, a Systematic Review

BACKGROUND

The standard treatment of T1 renal cell carcinoma (RCC) is (partial) nephrectomy. For patients where surgery is not the treatment of choice, for example in the elderly, in case of severe comorbidity, inoperability, or refusal of surgery, alternative treatment options are available. These treatment options include active surveillance (AS), radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), or stereotactic body radiotherapy (SBRT). In the present overview, the efficacy, safety, and outcome of these different options are summarized, particularly focusing on recent developments.

MATERIALS AND METHODS

Databases of MEDLINE (through PubMed), EMBASE, and the Cochrane Library were systematically searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The search was performed in December 2016, and included a search period from 2010 to 2016. The terms and synonyms used were renal cell carcinoma, active surveillance, radiofrequency ablation, microwave ablation, cryoablation and stereotactic body radiotherapy.

RESULTS

The database search identified 2806 records, in total 73 articles were included to assess the rationale and clinical evidence of alternative treatment modalities for small renal masses. The methodological quality of the included articles varied between level 2b and level 4.

CONCLUSION

Alternative treatment modalities, such as AS, RFA, CA, MWA, and SBRT, are treatment options especially for those patients who are unfit to undergo an invasive treatment. There are no randomized controlled trials available comparing surgery and less invasive modalities, leading to a low quality on the reported articles. A case-controlled registry might be an alternative to compare outcomes of noninvasive treatment modalities in the future.

Diagnostic accuracy of contrast-enhanced ultrasound for characterization of kidney lesions in patients with and without chronic kidney disease

BACKGROUND

Patients with chronic kidney disease are at increased risk of cystic kidney disease that requires imaging monitoring in many cases. However, these same patients often have contraindications to contrast-enhanced computed tomography and magnetic resonance imaging. This study evaluates the accuracy of contrast-enhanced ultrasound (CEUS), which is safe for patients with chronic kidney disease, for the characterization of kidney lesions in patients with and without chronic kidney disease.

METHODS

We performed CEUS on 44 patients, both with and without chronic kidney disease, with indeterminate or suspicious kidney lesions (both cystic and solid). Two masked radiologists categorized lesions using CEUS images according to contrast-enhanced ultrasound adapted criteria. CEUS designation was compared to histology or follow-up imaging in cases without available tissue in all patients and the subset with chronic kidney disease to determine sensitivity, specificity and overall accuracy.

RESULTS

Across all patients, CEUS had a sensitivity of 96% (95% CI: 84%, 99%) and specificity of 50% (95% CI: 32%, 68%) for detecting malignancy. Among patients with chronic kidney disease, CEUS sensitivity was 90% (95% CI: 56%, 98%), and specificity was 55% (95% CI: 36%, 73%).

CONCLUSIONS

CEUS has high sensitivity for identifying malignancy of kidney lesions. However, because specificity is low, modifications to the classification scheme for contrast-enhanced ultrasound could be considered as a way to improve contrast-enhanced ultrasound specificity and thus overall performance. Due to its sensitivity, among patients with chronic kidney disease or other contrast contraindications, CEUS has potential as an imaging test to rule out malignancy.

TRIAL REGISTRATION

This trial was registered in clinicaltrials.gov, NCT01751529 .

Bilateral benign renal oncocytomas and the role of renal biopsy: single institution review

BACKGROUND

The goal was to assess the natural history and management of patients with pathologically proven bilateral (synchronous) RO after undergoing initial partial nephrectomy (PN).

METHODS

All patients underwent either robotic/laparoscopic or open PN by two experienced genitourinary oncologists from 2005-2013. Final pathology was determined by surgical excision, CT-guided percutaneous core biopsy (CT-biopsy) or fine needle aspiration (FNA). Patient demographics, tumor characteristics (pathologic data, location, size) type of surgery, pre/post estimated glomerular filtration rate (eGFR) and surgical complications were recorded.

RESULTS

Twelve patients were identified with bilateral RO. Median age at the time of surgery was 68 years (46-77) (Table 1). The median size of the largest tumor(s) resected was 2.75 cm (1.5-5.5 cm) and second largest tumor(s) was 1.75 cm (1.0-4.0 cm). Four patients underwent bilateral staged PN and one patient underwent simultaneous bilateral PN (horseshoe kidney). Two patients underwent RFA at the time of biopsy of the contralateral mass after PN. Five patients underwent CT-bx/FNA (5/5) of the contralateral mass followed by active surveillance. Mean follow up was 34 months. There was no significant change in median creatinine pre- and post-operatively. One patient was lost to follow up and one patient died of unknown causes 5 years post-operatively. eGFR decreased an average of 16.96% post-operatively, including a single patient whose eGFR increased by 7.8% after surgery and a single patient whose eGFR did not change (Table 2).

CONCLUSIONS

Patients with bilateral renal masses and pathologically proven RO can be safely managed with active surveillance after biopsy confirmation of the contralateral mass.

The role of active surveillance of small renal masses

INTRODUCTION

The use of modern abdominal imaging modalities have led in recent years to an increased incidental diagnosis of small renal masses (SRMs), especially in elderly patients. The natural history of SRMs has been historically poorly understood because most have been traditionally surgically removed soon after diagnosis. However, several studies of active surveillance (AS) of SRMs have been published in the last decade.

METHODS

A review of English-language publications on AS of SRMs was performed from 1995 to 2015 using the Medline, Embase and Web of Science databases. Fifty-six articles were selected based on their scientific relevance and critically analysed.

RESULTS

When followed conservatively with serial imaging, SRMs have variable growth rates with an average of 0.31 cm/year in the largest multicenter analysis. A significant number of SRMs have a slow growth and some have zero growth under surveillance. The risk of progression to metastatic disease during AS is rare (1-2%). Population-based analyses in older patient populations (>75 years) fail to show a benefit in cancer-specific mortality for surgical treatment of SRMs.

DISCUSSION

The standard of care for localized renal tumors is surgery. In elderly or unfit patients with decreased life expectancy, it is reasonable to propose an initial period of AS, with delayed intervention for those tumors which exhibit a fast growth during follow-up. At present AS is not recommended in younger and fit patients and for masses >4 cm at diagnosis outside clinical trials. Percutaneous needle biopsies of renal tumors have the potential to characterize histologically SRMs at diagnosis, thereby providing useful information for the selection of the best suited patients for AS.

CONCLUSIONS

Most SRMs are benign tumors or RCCs with a relatively indolent clinical behaviour. AS can be offered to patients with SRMs and decreased life expectancy. Prospective series of AS of histologically confirmed RCCs are needed to confirm the long term safety of this conservative approach.

Update on active surveillance for clinical T1 renal tumors

PURPOSE OF REVIEW

The purpose is to discuss current data on the utilization and outcomes of active surveillance for T1a renal masses. Specifically, to address which patients are optimal for active surveillance and how their outcomes differ from those undergoing immediate treatment.

RECENT FINDINGS

Although nephron sparing surgery is the standard of care for small renal masses (SRMs), active surveillance is becoming a more popular intervention given the results of prospective studies revealing active surveillance to be safe and have excellent cancer-specific survival with intermediate follow-up. Older and sicker patients have competing risk of death from other causes when diagnosed with a SRM.

SUMMARY

Active surveillance is becoming a more popular treatment modality for SRMs given the increasing number of incidental diagnoses and better understanding of their often indolent course. Active surveillance with delayed intervention is a well-tolerated treatment modality and appears to have the most benefit for those patients that are older with more comorbidities.

Review of renal cell carcinoma and its common subtypes in radiology

Representing 2%-3% of adult cancers, renal cell carcinoma (RCC) accounts for 90% of renal malignancies and is the most lethal neoplasm of the urologic system. Over the last 65 years, the incidence of RCC has increased at a rate of 2% per year. The increased incidence is at least partly due to improved tumor detection secondary to greater availability of high-resolution cross-sectional imaging modalities over the last few decades. Most RCCs are asymptomatic at discovery and are detected as unexpected findings on imaging performed for unrelated clinical indications. The 2004 World Health Organization Classification of adult renal tumors stratifies RCC into several distinct histologic subtypes of which clear cell, papillary and chromophobe tumors account for 70%, 10%-15%, and 5%, respectively. Knowledge of the RCC subtype is important because the various subtypes are associated with different biologic behavior, prognosis and treatment options. Furthermore, the common RCC subtypes can often be discriminated non-invasively based on gross morphologic imaging appearances, signal intensity on T2-weighted magnetic resonance images, and the degree of tumor enhancement on dynamic contrast-enhanced computed tomography or magnetic resonance imaging examinations. In this article, we review the incidence and survival data, risk factors, clinical and biochemical findings, imaging findings, staging, differential diagnosis, management options and post-treatment follow-up of RCC, with attention focused on the common subtypes.

The Past, Present, and Future in Management of Small Renal Masses

Management of small renal masses (SRMs) is currently evolving due to the increased incidence given the ubiquity of cross-sectional imaging. Diagnosing a mass in the early stages theoretically allows for high rates of cure but simultaneously risks overtreatment. New consensus guidelines and treatment modalities are changing frequently. The multitude of information currently available shall be summarized in this review. This summary will detail the historic surgical treatment of renal cell carcinoma with current innovations, the feasibility and utility of biopsy, the efficacy of ablative techniques, active surveillance, and use of biomarkers. We evaluate how technology may be used in approaching the small renal mass in order to decrease morbidity, while keeping rates of overtreatment to a minimum.