Active Surveillance in Small Renal Masses in the Elderly: A Literature Review

Clear cell likelihood score may improve diagnosis and management of renal masses

The detection of solid renal masses has increased over time due to incidental findings during imaging studies conducted for unrelated medical conditions. Approximately 20% of lesions measuring less than 4 cm are benign and 80% are malignant. Clear cell renal cell carcinoma (ccRCC) is the most frequent among renal carcinomas, responsible for 65-80% of cases. The increased detection of renal masses facilitates early diagnosis and treatment. However, it also leads to more invasive interventions, which result in higher morbidity and costs. Currently, only histological analysis can offer an accurate diagnosis. Surgical nephron loss significantly elevates morbidity and mortality rates. Active surveillance represents a conservative management approach for patients diagnosed with a solid renal mass that is endorsed by both American Urological Association and the European Society for Medical Oncology. However, active surveillance is used in a minority of patients and varies across institutions. The lack of clinical studies using a standardized approach to incidentally detected small renal masses precludes the widespread use of active surveillance. Hence, there is an urgent need for better patient selection, distinguishing those who require surgery from those suitable for active surveillance. The clear cell likelihood score (ccLS) represents a novel MRI tool for assessing the probability of a renal mass being a ccRCC. In this study, we present a comprehensive review of renal masses and their evaluation using the ccLS to facilitate shared decision between urologists and patients.

The Detrimental Effect of Metabolic Syndrome on Long-term Renal Function in Patients Undergoing Elective Partial Nephrectomy for Small Renal Masses

Background and objective

Metabolic syndrome (MetS) is a clinical condition associated with higher rates of overall and cardiovascular mortality. There is scarce evidence regarding the impact of MetS on surgical and functional outcomes for patients undergoing partial nephrectomy (PN) for clinically localized small renal masses (SRMs).

Methods

We analyzed data from a prospectively maintained institutional database for 690 patients with cT1a renal cancer undergoing PN between 2000 and 2023 at a tertiary referral center. MetS was defined according to international guidelines. Cumulative incidence curves were used to estimate the 5-yr risk of stage IIIB-V chronic kidney disease (CKD) stage and other-cause mortality (OCM). Multivariable regression models were used to analyze the impact of MetS on the risk of complications, acute kidney injury (AKI), stage IIIB-V CKD, and OCM.

Key findings and limitations

Overall, 10% of the PN cohort had MetS. The MetS group was older (median age 70 yr, interquartile range [IQR] 65-74 vs 61 yr, IQR 50-69; p < 0.001) and had worse preoperative kidney function (median estimated glomerular filtration rate 65 [IQR 62-81] vs 88 [IQR 69-98] ml/min/1.73 m2; p < 0.001) than the group without MetS. The MetS group had higher incidence of complications (odds ratio [OR] 1.81, 95% confidence interval [CI] 1.05-3.08; p = 0.03) and postoperative AKI (OR 3.17, 95% CI 1.54-6.41; p = 0.001). The 5-yr risk of stage IIIB-V CKD (45% vs 7.2%; hazard ratio [HR] 2.34, 95% CI 1.27-4.30; p = 0.006) and OCM (14% vs 3.5%; HR 3.00, 95% CI 1.06-8.55; p = 0.039) were also higher in the MetS group. The main limitations are the extended accrual time and unmeasured confounders that could potentially affect outcomes.

Conclusions and clinical implications

Patients with MetS had worse postoperative, functional, and survival outcomes after SRM surgery in comparison to patients without MetS. Multidisciplinary care could help in reducing the preoperative metabolic burden in these patients. Further research should explore if alternative approaches (eg, surveillance or focal therapy) could minimize postoperative comorbidities and protect long-term renal function in this population.

Patient summary

Patients with a condition called metabolic syndrome who have part of their kidney removed for small kidney tumors are at higher risk of complications and long-term kidney issues. Patient care from a multidisciplinary team could help in reducing the metabolic burden before surgery. Further research is needed to explore if less invasive treatment options could reduce these risks.

The success rate of small renal mass core needle biopsy and its impact on lowering benign resection rate

BACKGROUND

Small renal mass (SRM) biopsy remains under-utilized due to stigma. Meanwhile, the alarmingly high benign findings in resected kidney masses highlight the need for improved preoperative diagnosis and patient selection.

METHODS

The purpose of this study is to review the success rate of SRM biopsy and to evaluate its impact on patient management. A total of 168 percutaneous image-guided core needle biopsies (CNBs) of SRMs were retrieved at a tertiary academic center between 2015 and 2019. Subsequent treatment choices, side effects and outcomes were retrospectively reviewed.

RESULTS

The diagnostic rate of CNB was 86.9%. Benign neoplasms accounted for a significant portion (14.3%) of SRM. Renal cell carcinomas (RCCs) were the most common diagnoses (69.6%) as expected. In biopsy-resection correlation, the positive predictive value of CNB was 100%. Tumor typing and subtyping by CNB were highly accurate, 100% and 98.3% respectively. Nuclear grading for clear cell RCC was accurate in 83.8% cases. The CNB results had significant impact on treatment. Most patients with RCCs underwent either resection (54.1%) or ablation (33.9%), in contrast to observation in benign neoplasms (90.5%). Most importantly, the benign resection rate (3.2%) in this series was much lower than the national average.

CONCLUSION

CNB provided accurate diagnoses for the majority of SRMs and revealed benign diagnoses in a subset of clinically suspicious lesions. Employment of CNB in suspicious SRM may help avoid overtreatment for benign lesions.

Morbidity of elective surgery for localized renal masses among elderly patients: A contemporary multicenter study

BACKGROUND

The aging population and the incidence of renal cell carcinoma (RCC) are increasing worldwide. Over 25% of newly diagnosed LRM (localized renal masses) occur in patients over the eighth decade of life. The decision-making and treatment approach to LRM in this population represents a clinical dilemma due to inherited decreased functional reserve and competing mortality risks. Current literature reports conflicting evidence regarding age as a risk factor for worst surgical outcomes. As such, we aimed to evaluate the contemporary morbidity of elective surgery for LRM among elderly patients, focusing on intraoperative and postoperative complications.

METHODS

After Ethical Committee approval, we queried our prospectively maintained databases to identify patients with preoperative eGFR ≥60 ml/min/1.73 m [(David and Bloom, 2022) 22 and a normal contralateral kidney who underwent partial or radical nephrectomy (PN or RN) for a single cT1-T2N0M0 LRM between 1/2015-12/2021 at four high-volume European Academic Institutions. Patients were categorized by age groups: <50 yrs (young) vs. 50-75 (middle-aged) yrs vs.> 75 yrs (elderly). Postoperative complications were recorded according to Clavien-Dindo (CD) classification. The primary objectives were the proportion of patients experiencing intraoperative (IOC), any grade (AGC), and high-grade postoperative complications (HGC), defined as CD grade 3-5.

RESULTS

Overall, 2469/3076 (80.2%) patients met the inclusion criteria. Of these, 363 (14.7%) were young, 1682 (68.1%) were middle-aged, and 424 (17.2%) were elderly. Compared to middle-aged and young patients, elderly patients had a higher median Charlson Comorbidity Index (6 vs. 4 vs. 0, p < 0.01) and a higher proportion of cT1 renal mass (87.6% vs. 93.0% vs. 93.6%, p < 0.01). No differences among the study groups were found regarding surgical approach (open vs. minimally-invasive) and type of surgery (PN vs. RN). We found that older patients experienced similar IOC (4.5% vs. 4.2% vs. 3.3%, p = 0.7) and AGC (23.1% vs. 20.0% vs. 21.5%, p = 0.4) compared to middle-aged and young patients, respectively. Similarly, there were no significant differences in HGC between the study cohorts (0.7% vs. 1.4% vs. 1.7%, p = 0.8). At multivariable analysis, open approach and PN significantly predicted the occurrence of AGCs, while only the open surgical approach was associated with the occurrence of HGCs.

CONCLUSION

In kidney cancer tertiary referral centers, the risk of IOC and postoperative HGC after PN or RN for localized renal masses (LRM) is low, despite a non-negligible risk of AGC, especially in elderly patients. Further efforts should focus on identifying multidisciplinary strategies to select patients most likely to benefit from surgery among elderly candidates with LRMs and decrease the morbidity of surgery in this specific setting.

[Current concepts for perioperative systemic therapy in advanced renal cell carcinoma]

BACKGROUND

The incidence of renal cell carcinoma (RCC), one of the most common malignant tumors in Germany, continues to increase. Medical treatment is indicated in relapsed or metastatic disease.

MATERIALS AND METHODS

The article is based on the content of the recent guidelines and a selective literature search.

RESULTS

The use of the introduction of immune checkpoint inhibitors (ICI) and their combination with tyrosine kinase inhibitors (TKI) in particularly vulnerable patients has fundamentally changed the therapeutic landscape. The median overall survival was thus extended to > 40 months. However, until recently neither targeted nor conventional therapy could be established in (neo)adjuvant therapy. New data show survival benefit for patients at high risk of recurrence on adjuvant therapy with pembrolizumab.

CONCLUSIONS

Currently only pembrolizumab is approved in adjuvant therapy in Germany. Further studies and a longer follow-up will help us in the future in the classification of therapy with ICI and its combination with TKI in localized RCC.

Surgical waiting times and all-cause mortality in patients with non-metastatic renal cell carcinoma

OBJECTIVE

To examine the association between surgical waiting times (SWTs) and all-cause mortality (ACM) in non-metastatic patients with RCC, in relation to tumour stage.

PATIENTS AND METHODS

This nation-wide population-based cohort study included 9,918 M0 RCC patients registered in the National Swedish Kidney Cancer Register, between 2009 and 2021, followed-up for ACM until 9 December 2021, and having measured SWTs. The associations between primarily SWTs from date of radiological diagnosis to date of surgery (WRS) and secondarily SWTs from date of radiological diagnosis to date of treatment decision (WRT) and date of treatment decision to date of surgery (WTS), in relation to ACM, were analysed using Cox regression analysis, adjusted for clinical and demographic characteristics, stratified and unstratified according to T-stage.

RESULTS

During a mean follow-up time of 5 years (49,873 person-years), 23% (n = 2291) of the patients died. The adjusted hazard ratio (AHR) for WRS (months) for all patients was 1.03 (95% confidence interval [CI] = 1.02-1.04; p < 0.001). When subdividing WRS on T-stage, the AHRs were 1.03 (95% CI = 1.01-1.04; p < 0.001) and 1.05 (95% CI = 1.02-1.08; p = 0.003) for stages T1 and T3, respectively, while non-significant for T2 (p = 0.079) and T4 (p = 0.807). Similar results were obtained for WRT and WTS.

CONCLUSIONS

Prolonged SWTs significantly increased the risk of early overall death among patients with RCC. The increased risk of early death from any cause show the importance of shortening SWTs in clinical work of patients with this malignant disease.

Does histologic subtype impact overall survival in observed T1a kidney cancers compared with competing risks? Implications for biopsy as a risk stratification tool

OBJECTIVES

We sought to assess if adding a biopsy proven histologic subtype to a model that predicts overall survival that includes variables representing competing risks in observed, biopsy proven, T1a renal cell carcinomas, enhances the model's performance.

METHODS

The National Cancer Database was assessed (years 2004-2015) for patients with observed T1a renal cell carcinoma who had undergone renal mass biopsy. Kaplan-Meier curves were utilized to estimate overall survival stratified by histologic subtype. We utilized C-index from a Cox proportional hazards model to evaluate the impact of adding histologic subtypes to a model to predict overall survival for each stage.

RESULTS

Of 132 958 T1a renal masses identified, 1614 had biopsy proven histology and were managed non-operatively. Of those, 61% were clear cell, 33% papillary, and 6% chromophobe. Adjusted Kaplan-Meier curves demonstrated a difference in overall survival between histologic subtypes (P = 0.010) with greater median overall survival for patients with chromophobe (85.1 months, hazard rate 0.45, P = 0.005) compared to clear cell (64.8 months, reference group). Adding histology to a model with competing risks alone did not substantially improve model performance (C-index 0.65 vs 0.64 respectively).

CONCLUSIONS

Incorporation of histologic subtype into a risk stratification model to determine prognostic overall survival did not improve modeling of overall survival compared with variables representing competing risks in patients with T1a renal cell carcinoma managed with observation. These results suggest that performing renal mass biopsy in order to obtain tumor histology may have limited utility. Future studies should further investigate the overall utility of renal mass biopsy for observed T1a kidney cancers.

Renal Cell Carcinoma: A Complex Therapeutic Challenge in the Elderly

An increase in age and the occurrence of renal cell carcinoma have been positively correlated. A strict therapeutic protocol for early diagnosis, screening, prevention, and population awareness needs to be well-established as a rationale to approach the morbidity at a treatment-eligible phase in the aged. Genetic predisposition appears to have a minor role in the disease pathology. Imaging modalities, providing high-resolution images of the tumor, have undoubtedly benefitted the diseased subset in aiding the diagnosis, however, a preliminary guideline protocol for its early implication in concordance with the initial symptoms needs to be adopted. Burdening of the geriatric age group by concomitant co-morbidities further deteriorates the devastating effects of the primary tumor, which, in total, appear to evolve as a final, complex stage of the illness in the majority, leading to an eventual high mortality rate. Despite being a challenging task for managing the tumor, age should not be considered the sole treatment barrier for approaching the disease.

Comorbidity and frailty assessment in renal cell carcinoma patients

PURPOSE

Renal cell carcinoma (RCC) incidence has considerably increased during the last decades without any real impact on age-standardized mortality. It questions the relevance of aggressive treatments carrying potential side effects. Conservative management should be considered for frail patients. Comorbidity and frailty assessment in RCC patients is paramount before engaging a treatment.

METHODS

Narrative, non-systematic review based on PubMed and EMBASE search with the terms "renal neoplasm", "elderly, frail", "comorbidities", "active surveillance", "metastatic". The selection was restricted to articles written in English.

RESULTS

Comorbidity and frailty assessment go along with the cancer-specific aggressivity and intervention risks assessment. In localized disease, several standardized algorithms offer patient health evaluation to define how suitable the patient would be for curative treatment. The pre-operative American Society of Anesthesiologists and the age-adjusted Charlson's scores are the most widely used. At the metastatic stage, drug combinations based on immunotherapies and targeted therapies improved cancer outcomes at the price of significant toxicities. Frail patients are not always suitable for such strategies. Commonly used scores like the International Metastatic RCC Database Consortium or Memorial Sloan Kettering Cancer Center integrate features to define patients' risk groups, more specifically the Karnofsky Performance Score is an easy way to document the frailty.

CONCLUSIONS

Comorbidity and frailty have to be assessed at any stage of the RCC disease based on a standardized scoring system to define the most suitable treatment strategy ranging from surveillance to aggressive treatment.

Risk factors for progression of chronic kidney disease after robotic partial nephrectomy in elderly patients: results from a multi-institutional collaborative series

BACKGROUND

Robotic partial nephrectomy (RPN) in patients ≥75 years is certainly underused with concerns regarding surgical quality and a negligible impact on renal function. The aim of this study was to identify predictors of progression of chronic kidney disease for purely off-clamp (ocRPN) and on-clamp RPN (onRPN) in elderly patients on a multi-institutional series.

METHODS

A collaborative minimally-invasive renal surgery dataset was queried for "RPN" performed between July 2007 and March 2021 and "age≥75 years". A total of 205 patients matched the inclusion criteria. Descriptive analyses were used. Frequencies and proportions were reported for categorical variables while medians and interquartile ranges (IQR) were reported for continuous variables. Baseline, perioperative and functional data were compared between groups. New-onset of stages 3b,4,5 CKD in onRPN and ocRPN cohorts was computed by Kaplan-Meier analysis. Univariable and multivariable Cox regression analyses were performed to identify predictors of progression to severe CKD (sCKD [stages ≥3b]). For all statistical analyses, a two-sided p < 0.05 was considered significant.

RESULTS

Mean age of the cohort considered was 78 years (IQR 76-80). At a median follow-up of 29 months (IQR 14.5-44.5), new onset CKD-3b and CKD-4,5 stages was observed in 16.6% and 2.4% of patients, respectively. At Kaplan-Meier analysis, onRPN was associated with a significantly higher risk of developing sCKD (p=0.002). On multivariable analysis, hypertension (HR 2.64; 95% CI 1.14-6.11; p=0.023), on-clamp approach (HR 3.41; 95% CI 1.50-7.74; p=0.003) non-achievement of trifecta (HR 0.36; 95% CI 0.17-0.78; p=0.01) were independent predictors of sCKD.

CONCLUSIONS

RPN in patients≥75 years is a safe surgical option. On-clamp approach, hypertension and non-achievement of trifecta were independent predictors of sCKD in the elderly after RPN.

Clinical and radiological findings for small renal masses under active surveillance

OBJECTIVE

To analyze the experience performing active surveillance (AS) of small renal masses (SRMs) in our center and to correlate the evolution of SRMs under AS with clinical and radiological findings.

METHODS

Patients on AS between January 2012 until May 2020 for SRMs in our center have been included. Growth rate (GR) per year was analyzed and correlated with radiographic features. Patients with growth kinetics higher than 5mm/year during follow up were offered active treatment.

RESULTS

73 patients were included in AS: the mean age was 75.7 years, a mean initial tumour size of 21.2 mm, and a mean growth rate of 2.05 mm/year. Around 60 % had an ASA score of 3. The tumor size did not change over time in 43% of cases; in 4% we noticed a regression in size and in 52% of cases growth during follow-up (38% 1-5mm/year and 14% more than 5 mm/year). Delayed active treatment was indicated in 16 (21%) of cases. Treatment applied was as following: 2 radiofrequency ablations, 6 radical and 8 partial nephrectomies. A weak correlation was found between initial size and growth rate (r = 0.38, P = 0.02). No significant association was detected regarding any of the analyzed radiological findings and GR. With a mean follow up time of 33 months none of the patients presented metastatic progression.

CONCLUSION

Active surveillance is a feasible option for management of SRMs in selected patients without jeopardizing oncological safety. In our series, no clinical or radiological characteristics for predicting tumour growth were found.

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.

Upstaging to pT3a in Patients Undergoing Partial or Radical Nephrectomy for cT1 Renal Tumors: A Systematic Review and Meta-analysis of Outcomes and Predictive Factors

CONTEXT

Predictors of upstaging from cT1 to pT3a renal masses are poorly inquired, and this remains an area of controversial findings.

OBJECTIVE

To evaluate predictors and outcomes of upstaging from cT1 to pT3a in patients undergoing surgical removal of a renal tumor.

EVIDENCE ACQUISITION

A systematic literature search was performed to identify relevant articles using three electronic engines (PubMed, Embase, and Web of Science). Only studies looking at upstaging to pT3a in patients undergoing either partial nephrectomy (PN) or radical nephrectomy (RN) for cT1 renal tumor were included. Study selection was performed according to the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) statement.

EVIDENCE SYNTHESIS

Thirteen studies, including 21869 patients (cT1/pT3a: 1256 [5.7%]; cT1/pT1: 20613 [93.3%]), were identified. Patients in the upstaged group were older (weighted mean difference [WMD]: 3.89; p < 0.00001) and mostly male (odds ratio [OR]: 1.23; p = 0.04). Renal tumors were larger (WMD: 0.98; p < 0.00001), more complex (OR: 2.38; p < 0.0001), and with a higher rate of cT1b masses (OR: 3.36; p < 0.00001). The cT1/pT3a group had a higher rate of other renal cell carcinoma histological subtypes (OR: 1.59; p = 0.04), as well as higher odds of Fuhrman grade ≥3 (OR: 2.57; p < 0.00001) and positive surgical margins (OR: 1.85; p = 0.007). Five-year recurrence-free survival (RFS) was worse in the upstaged group (OR: 0.31; p = 0.02). Age (OR: 1.03; p < 0.00001), tumor size (OR: 1.51; p < 0.00001), and RENAL score (OR: 2.80; p = 0.0004) were predictors of upstaging. Upstaging was associated with overall survival (hazard ratio [HR]: 1.94; p = 0.05), cancer-specific survival (HR: 2.24; p = 0.007), and RFS (HR: 2.17; p < 0.00001).

CONCLUSIONS

Upstaging to pT3a in case of surgical removal of a cT1 renal tumor is an uncommon event, which however can translate into worse oncological outcomes. Both patient (older age) and tumor (larger size and higher complexity) characteristics are associated with a higher risk of upstaging. There is very limited evidence regarding whether RN would be better than PN in these cases. There remains an unmet need for tools to better characterize renal masses in the preoperative setting.

PATIENTS SUMMARY

About 6% of surgically treated localized renal tumors can be found to be locally advanced on final pathology after surgery. This "upstaging" can translate into worse oncological outcomes. There are patient and tumor characteristics that are associated with an increased the risk of upstaging.

Safety and oncological outcome following radiofrequency ablation of small renal masses in a single center

OBJECTIVE

To evaluate the safety and efficacy of percutaneous CT-guided radiofrequency ablation (RFA) for small renal masses (SRMs) at a large single-institution center during a period of 12 years.

MATERIALS AND METHODS

A total of 118 patients underwent RFA for SRM between July 2006 and July 2018 at our institution. We included demographic information, comorbidity, procedural details, and oncological outcome in the analysis. Survival analysis was performed using competing risk.

RESULTS

87 males and 31 females with median age 66 years underwent RFA. Median tumor size was 23 mm. Tumor biopsy was performed in 94% of cases, of which 56% were confirmed renal cell carcinoma (RCCs). Twenty-eight patients had benign tumors or underwent treatment for recurrence of prior RCC. Median follow-up of 5 years. Median Charlson Comorbidity Index was 5. Major complications occurred in 1.7%. No change in kidney function was observed. The initial treatment response was 98%. Among patients treated for newly diagnosed radiological suspected RCC without Von Hippel-Lindau or benign biopsy (90 pts), the cumulative incidence of radiological recurrence after 5 and 10 years was 6.6% (95% CI: 0.8-12%) and 16% (95% CI: 4.2-28%), respectively. Three patients died of RCC during follow-up. The cumulative incidence of kidney cancer death was 4.5% (95% CI: 4.3-13%) after 10 years. The incidence of other-cause mortality was 50% (95% CI: 34-67%).

CONCLUSION

CT-guided RFA is a safe and effective treatment option for patients unsuitable for surgery. RFA is a good alternative to partial or radical nephrectomy for SRMs, although randomized trials comparing surgery to minimally invasive thermal ablation techniques are missing.

Adequacy of Unenhanced MRI for Surveillance of Small (Clinical T1a) Solid Renal Masses

OBJECTIVE. The purpose of this study was to determine if contrast enhancement is necessary for MRI surveillance of clinical T1a (cT1a) solid renal masses. MATERIALS AND METHODS. With institutional review board approval, 36 patients who underwent two or more contrast-enhanced (CE) MRI examinations (median, four examinations; range, two to 10 examinations) for surveillance of 39 cT1a solid renal masses between 2009 and 2019 (median time between scans, 2 years; range, 1-7 years) were evaluated. Two radiologists independently measured renal mass size and assessed tumor stage in two sessions for baseline and follow-up examinations using T1-weighted nephrographic phase CE-MRI and unenhanced single-shot T2-weighted MRI in mixed order with a 4-week washout period. Comparisons were performed using the Wilcoxon sign-rank test and Pearson correlation. Bland-Altman and intraclass correlation determined interobserver agreement. RESULTS. Mean size ± SD of renal masses on CE-MRI and T2-weighted MRI were 18 ± 5 mm (range, 9-37 mm) and 18 ± 5 mm (range, 9-37 mm) for radiologist 1 and 19 ± 7 mm (range, 10-39 mm) and 19 ± 6 mm (range, 10-39 mm) for radiologist 2 with near perfect correlation (for radiologist 1, β = 0.9897; for radiologist 2, β = 0.9317; p < .001). Interob-server agreement for measurements comparing radiologist 1 and radiologist 2 on CEMRI and T2-weighted MRI and intraobserver agreement for measurements on CE-MRI and T2-weighted MRI were excellent. Mean growth rate of renal masses measured on CE-MRI and T2-weighted MRI were 2 ± 2 mm (range, -5 to 8 mm) and 2 ± 3 mm (range, -3 to 8 mm) for radiologist 1 and 3 ± 5 mm (range, -1 to 18 mm) and 3 ± 6 mm (range, -1 to 24 mm) for radiologist 2 with high correlation (for radiologist 1, β = 0.8313 [p < .001]; for radiologist 2, β = 0.848 [p = .002]). At baseline, all tumors were subjectively cT1a on CE-MRI and T2-weighted MRI (p > .99, intraclass correlation coefficient [ICC] = 1). During follow-up, one mass progressed to T3 on CE-MRI and T2-weighted MRI for radiologist 1 and radiologist 2 (p > .99, ICC = 1). CONCLUSION. In this study, size measurements on unenhanced T2-weighted MRI had near perfect correlation to measurements using CE-MRI in cT1a solid renal masses undergoing surveillance, with high agreement between and within observers. Clinical staging did not differ comparing T2-weighted MRI and CE-MRI, with near perfect agreement. Contrast enhancement is not necessary for follow-up size measurements in cT1a solid renal masses with MRI.

Collaborative Review: Factors Influencing Treatment Decisions for Patients with a Localized Solid Renal Mass

CONTEXT

With the addition of active surveillance and thermal ablation (TA) to the urologist's established repertoire of partial (PN) and radical nephrectomy (RN) as first-line management options for localized renal cell carcinoma (RCC), appropriate treatment decision-making has become increasingly nuanced.

OBJECTIVE

To critically review the treatment options for localized, nonrecurrent RCC; to highlight the patient, renal function, tumor, and provider factors that influence treatment decisions; and to provide a framework to conceptualize that decision-making process.

EVIDENCE ACQUISITION

A collaborative critical review of the medical literature was conducted.

EVIDENCE SYNTHESIS

We identify three key decision points when managing localized RCC: (1) decision for surveillance versus treatment, (2) decision regarding treatment modality (TA, PN, or RN), and (3) decision on surgical approach (open vs minimally invasive). In evaluating factors that influence these treatment decisions, we elaborate on patient, renal function, tumor, and provider factors that either directly or indirectly impact each decision point. As current nomograms, based on preselected patient datasets, perform poorly in prospective settings, these tools should be used with caution. Patient decision aids are an underutilized tool in decision-making.

CONCLUSIONS

Localized RCC requires highly nuanced treatment decision-making, balancing patient- and tumor-specific clinical variables against indirect structural influences to provide optimal patient care.

PATIENT SUMMARY

With expanding treatment options for localized kidney cancer, treatment decision is highly nuanced and requires shared decision-making. Patient decision aids may be helpful in the treatment discussion.

Triggers for delayed intervention in patients with small renal masses undergoing active surveillance: a systematic review

INTRODUCTION

Patients with small renal masses (SRM) can be exposed to overdiagnosis and overtreatment. As such, active surveillance (AS) is recommended by all Guidelines for selected patients. However, it remains underutilized. One key reason is the lack of consensus on the factors prompting delayed intervention (DI). Herein we provide an updated overview of the triggers for DI in patients with SRMs initially undergoing AS.

EVIDENCE ACQUISITION

A systematic review of the English-language literature was performed according to the PRISMA statement recommendations using the MEDLINE, Cochrane Central Register of Controlled Trials and Web of Science databases.

EVIDENCE SYNTHESIS

Overall, 10 prospective studies including 1870 patients were included. Median patient age ranged between 64 and 75 years, while median tumor size between 1.7 cm to 2.3 cm. The proportion of cystic SRMs ranged from 0% to 30%. Baseline renal tumor biopsy was performed in 7-45.2% of patients. Among these, malignant histology was found in 28.5%-83.3% of cases. Overall, the median growth rate of SRMs ranged between 0.10 and 0.27 cm/year. The proportion of patients undergoing DI ranged between 7% and 44%, after a median AS period of 12-27 months. The most commonly performed type of DI was surgery. Of resected SRMs, 0% to 30% were benign. The actual triggers for DI were either tumor-related (renal mass growth, stage progression, development of local complications/symptoms) or patient-related (patient preference, improved medical conditions, or qualification for other surgical procedures). At a median follow-up of 21.7 - 57-6 months, the proportion of patients experiencing metastatic disease, cancer-specific and other-cause mortality was 0-3.1%, 0-4% and 0-45.6%, respectively.

CONCLUSIONS

The available evidence shows that both tumor-related and patient-related factors are ultimate triggers for DI in patients with SRMs undergoing AS. However, the level of evidence is still low and further research is needed to individualize AS strategies according to both tumor biology and patient-related characteristics and values.

Renal tumor growth rate in patients with previously normal CT scan: Analysis of the initial stage of growth

OBJECTIVE

Most of the studies regarding natural history of renal masses are based on active surveillance series and suggest that the renal masses have a slow growth rate. Nevertheless, only a few studies report the time between a normal computed tomography (CT) scan to the first detection of a tumor. We aimed to analyze the growth rate in newly diagnosed kidney tumors.

MATERIAL AND METHODS

We analyzed patients with enhancing renal masses that developed after a normal CT scan, which was performed at most 12 months earlier. Variables examined included patient age, gender, tumor size, volume, tumor linear growth rate (LGR). All cases were surgically treated. Mann-Whitney U test was used to compare variables. A p<0.05 was considered as statistically significant.

RESULTS

We found 31 patients with 33 lesions. Male to female ratio was 1.58 (19/12). The average age was 59.2 years (standard deviation [SD]±12.1), and the mean tumor size was 4.27 cm (SD±4.3). Tumor LGR was 0.87 cm/month (range: 0.28-1.66) and presumed to be 10.4 cm at 1 year (range: 3.36-19.9). Tumor LGR for time detection at <6 month or ≥6 months were 1.1 cm/month and 0.68 cm/month (range: 0.27-1.08 and 0.88-1.76, respectively; p=0.0004), respectively. Tumor LGRs for low- and high-grade tumors were 0.89 cm/month and 0.83 cm/month (p=0.65), respectively. Median volume was 36.1 cm³ (range: 2.61-143.7), and for low and high grade the median volumes were 27.9 cm³ and 47.6 cm³, respectively (p=0.54). Malignant pathology was present in 93.9 % (31 of 33) of masses (lesions).

CONCLUSION

We found differences in tumor LGR in tumors detected before and after 6 months. We did not find any correlation between tumor growth rate and Fuhrman grade system, gender, histology, or age. We found the highest LGR published up to date.

Active surveillance for small renal masses in elderly patients does not increase overall mortality rates compared to primary intervention: a propensity score weighted analysis

BACKGROUND

The aim of the study was to test the effect of active surveillance (AS) versus primary intervention (PI) on overall mortality (OM) in elderly patients diagnosed with SRM.

METHODS

Elderly patients (75 years or older) diagnosed with SRMs (<4 cm) and treated with either PI (i.e. partial nephrectomy or kidney ablation) or AS between 2009 and 2018 were abstracted from the renal surgery in the elderly (RESURGE) and Delayed Intervention and Surveillance for small Renal Masses (DISSRM) datasets, respectively. OM rates were estimated among groups with Kaplan Meier method and Cox proportional hazards regression models after applying inverse probability of treatment weighting (IPTW). Multivariable logistic regression model was used to estimate IPTW. Covariates of interest were those unbalanced and/or significantly correlated with the treatment choice or with OM.

RESULTS

A total of 483 patients were included; 121 (25.1%) underwent AS. Sixty patients (12.4%) died. Overall, 6.7% of all deaths were related to cancer. IPTW-Kaplan Meier curves showed a 5-year overall survival rates of 70.0±3.5% and 73.2±4.8% in AS and PI groups, respectively (IPTW-Log-rank P value=0.308). IPTW-Cox regression model did not show meaningfully increased OM rates in AS group (HR: 1.31, 95% CI: 0.69-2.49).

CONCLUSIONS

AS represents an appealing treatment option for very elderly patients presenting with SRM, as it avoids the risks of a PI while not compromising the survival outcomes of these patients.

Analyzing National Incidences and Predictors of Open Conversion During Minimally Invasive Partial Nephrectomy for cT1 Renal Masses

Objectives: To analyze predictors of open conversion during minimally invasive partial nephrectomy (MIPN) for cT1 renal masses. Methods: The National Cancer Database (NCDB) was investigated for kidney cancer patients who underwent partial nephrectomy (PN) between 2010 and 2015. Patients who underwent MIPN were stratified into converted and nonconverted groups. Sociodemographics, facility characteristics, and surgical outcomes were compared between the two groups, and multivariate logistic regression model was fitted to identify independent predictors of open conversion. Results: In total, 54,246 patients underwent PN for kidney cancer during the 6-year period. Of those, 18,994 (35%) were open partial nephrectomies (OPNs) and 35,252 (64%) were MIPN. Overall, 1010 (2.87%) of MIPNs were converted to OPN. There was an increasing utilization of MIPN from 50.35% in 2010 to 74.73% in 2015. Patients who had open conversion had more 30-day readmissions (5.95% vs 3.31%, p < 0.01). On multivariate analysis; high-volume facility (>30 MIPNs/year), year of surgery (2015 vs 2010), and robotic approach predicted a lower likelihood of conversion (odds ratio [OR] 0.52, confidence interval [CI] 0.44-0.62; OR 0.59, CI 0.47-0.73; and OR 0.31, CI 0.27-0.35; respectively, p < 0.001 for all). Conversely, Medicaid (vs private insurance; OR 1.75, CI 1.39-2.19, p < 0.001) and male sex (OR 1.26, CI 1.11-1.44, p < 0.001) were independent predictors of conversion. Conclusions: Open conversion in MIPN occurred in 2.87% of cases. There was an increasing utilization of MIPN associated with decreased conversion rates. Higher volume hospitals and progressing year of surgery were associated with less likelihood of conversion.

[Geriatric specificities of localized renal cell carcinoma]

PURPOSE

To describe the epidemiology of renal cell carcinoma (RCC) and its natural history in the elderly patient. To propose adaptations of geriatric evaluation specific to RCC. Recall therapeutic options and the treatment options specific to elderly patients.

METHOD

Bibliographic research from the Medline bibliographic database (NLM Pubmed tool) and Embase, as well as on the websites of scientific societies of geriatrics, from the National Cancer Institute using the following keywords: elderly, geriatrics, renal cell carcinoma, small renal mass, diagnosis, treatment.

RESULTS

The incidence of RCC increases in France and peaks between 70 and 80 years. This increase in incidence is mainly due to the diagnosis of small renal masses (SMR). The specific mortality of RCC increases with age (at least between 75 and 95 years). Tumor biopsy, especially of SMR, should be considered in the elderly patient. The geriatric assessment of patients with CaR has no specificity apart from specific evaluation of renal function and operative risk. There is no prospective therapeutic trials dedicated to elderly patients with localized RCC. Surgical treatment requires the use of fast track protocol (the modalities of which are being elaborated) in which geriatricians play a key role throughout the process. The role of percutaneous ablative treatment should be better defined in elderly patients. However, given their low specific mortality, surveillance of SRM (at least initially) is probably an interesting option, certainly under-used, although its impact on quality of life remains to be clarified. The overarching goal of geriatric oncology must guide the decisions of care in the older patient with CaR: first, the respect of patient-specific expectations and secondly the search for an overall clinical benefit; objectives that have no reason to be restricted to elderly patients.

CONCLUSION

RCC is becoming a predominantly elderly cancer. It responds to the current general diagnostic and therapeutic guidelines. It is desirable that clinical research help to better define the respective roles of percutaneous biopsy and treatment of localized RCC.