Contemporary management of renal cell carcinoma (RCC) in Victoria: implications for longer term outcomes and costs

Trends and predictors of changes in renal function after radical nephrectomy for renal tumours

BACKGROUND

Chronic kidney disease (CKD) is a common postoperative complication in patients who undergo radical nephrectomy for renal tumours. However, the factors influencing long-term renal function require further investigation.

OBJECTIVE

This study was designed to investigate the trends in renal function changes and risk factors for renal function deterioration in renal tumour patients after radical nephrectomy.

METHODS

We monitored changes in renal function before and after surgery for 3 years. The progression of renal function was determined by the progression and degradation of CKD stages. Univariate and multivariate logistic regression analyses were used to analyse the causes of renal function progression.

RESULTS

We analysed the data of 329 patients with renal tumours who underwent radical nephrectomies between January 2013 and December 2018. In this study, 43.7% of patients had postoperative acute kidney injury (AKI), and 48.3% had CKD at advanced stages. Further research revealed that patients' renal function stabilized 3 months after surgery. Additionally, renal function changes during these 3 months have a substantial impact on the progression of long-term renal function changes in patients.

CONCLUSION

AKI may be an indicator of short-term postoperative changes in renal function. Renal function tests should be performed in patients with AKI after radical nephrectomy to monitor the progression of functional impairment, particularly within the first 3 months after radical nephrectomy.

Machine learning models for predicting the onset of chronic kidney disease after surgery in patients with renal cell carcinoma

BACKGROUND

Patients with renal cell carcinoma (RCC) have an elevated risk of chronic kidney disease (CKD) following nephrectomy. Therefore, continuous monitoring and subsequent interventions are necessary. It is recommended to evaluate renal function postoperatively. Therefore, a tool to predict CKD onset is essential for postoperative follow-up and management.

METHODS

We constructed a cohort using data from eight tertiary hospitals from the Korean Renal Cell Carcinoma (KORCC) database. A dataset of 4389 patients with RCC was constructed for analysis from the collected data. Nine machine learning (ML) models were used to classify the occurrence and nonoccurrence of CKD after surgery. The final model was selected based on the area under the receiver operating characteristic (AUROC), and the importance of the variables constituting the model was confirmed using the shapley additive explanation (SHAP) value and Kaplan-Meier survival analyses.

RESULTS

The gradient boost algorithm was the most effective among the various ML models tested. The gradient boost model demonstrated superior performance with an AUROC of 0.826. The SHAP value confirmed that preoperative eGFR, albumin level, and tumor size had a significant impact on the occurrence of CKD after surgery.

CONCLUSIONS

We developed a model to predict CKD onset after surgery in patients with RCC. This predictive model is a quantitative approach to evaluate post-surgical CKD risk in patients with RCC, facilitating improved prognosis through personalized postoperative care.

Variability in surgical management of kidney cancer between urban and rural hospitals in Queensland, Australia: a population-based analysis

Background

International guidelines recommend partial over radical nephrectomy for management of kidney tumours, due to perceived advantages of kidney function preservation. In Queensland, oncological nephrectomy is performed in both metropolitan and rural hospitals. Previous studies have shown that patients from rural areas with kidney tumours are less likely to undergo partial nephrectomy compared with those in major cities. The aim of this study was to investigate patterns of partial nephrectomy according to geographical area, and to identify patient- and health-service-level characteristics associated with partial nephrectomy.

Methods

All 3,799 incident kidney cancer cases in Queensland (Jan 2009 to Dec 2014) were ascertained. Patients aged <18 yrs (n=47), who did not receive surgery (n=988), or had end-stage kidney disease (ESKD) before surgery (n=17) were excluded. The final sample included 2,747 patients. Data were analysed using multivariable logistic regression in order to identify associations with partial nephrectomy.

Results

Of 2,747 patients, 637 (25%) underwent partial nephrectomy. The likelihood of undergoing partial nephrectomy increased with more recent year of surgery (P<0.001) and higher socioeconomic status (P<0.001). The likelihood of undergoing partial nephrectomy decreased for patients managed in lower-volume centres (P=0.004), with increasing age (P<0.001), and hospital location outside of a major city (P<0.001). Overall, the number of nephrectomies, and proportion/number of partial nephrectomies, performed in rural hospitals has increased over the study period.

Conclusions

Our results suggest that, although patients who are managed in major cities are more likely to undergo partial nephrectomy, likelihood of undergoing partial nephrectomy in rural centres is increasing, consistent with international best practice.

A Simple Clinical Tool for Stratifying Risk of Clinically Significant CKD after Nephrectomy: Development and Multinational Validation

BACKGROUND

Clinically significant CKD following surgery for kidney cancer is associated with increased morbidity and mortality, but identifying patients at increased CKD risk remains difficult. Simple methods to stratify risk of clinically significant CKD after nephrectomy are needed.

METHODS

To develop a tool for stratifying patients' risk of CKD arising after surgery for kidney cancer, we tested models in a population-based cohort of 699 patients with kidney cancer in Queensland, Australia (2012-2013). We validated these models in a population-based cohort of 423 patients from Victoria, Australia, and in patient cohorts from single centers in Queensland, Scotland, and England. Eligible patients had two functioning kidneys and a preoperative eGFR ≥60 ml/min per 1.73 m². The main outcome was incident eGFR <45 ml/min per 1.73 m² at 12 months postnephrectomy. We used prespecified predictors-age ≥65 years old, diabetes mellitus, preoperative eGFR, and nephrectomy type (partial/radical)-to fit logistic regression models and grouped patients according to degree of risk of clinically significant CKD (negligible, low, moderate, or high risk).

RESULTS

Absolute risks of stage 3b or higher CKD were <2%, 3% to 14%, 21% to 26%, and 46% to 69% across the four strata of negligible, low, moderate, and high risk, respectively. The negative predictive value of the negligible risk category was 98.9% for clinically significant CKD. The c statistic for this score ranged from 0.84 to 0.88 across derivation and validation cohorts.

CONCLUSIONS

Our simple scoring system can reproducibly stratify postnephrectomy CKD risk on the basis of readily available parameters. This clinical tool's quantitative assessment of CKD risk may be weighed against other considerations when planning management of kidney tumors and help inform shared decision making between clinicians and patients.

Tumor size and postoperative kidney function following radical nephrectomy

Background: Chronic kidney disease (CKD) following nephrectomy for kidney tumors is common, and both patient and tumor characteristics may affect postoperative kidney function. Several studies have reported that surgery for large tumors is associated with a lower likelihood of postoperative CKD, but others have reported CKD to be more common before surgery in patients with large tumors. Objective: The aim of this study was to clarify inconsistencies in the literature regarding the prognostic significance of tumor size for postoperative kidney function. Study design and setting: We analyzed data from 944 kidney cancer patients managed with radical nephrectomy between January 2012 and December 2013, and 242 living kidney donors who underwent surgery between January 2011 and December 2014 in the Australian states of Queensland and Victoria. Multivariable logistic regression was used to assess the primary outcome of CKD upstaging. Structural equation modeling was used to evaluate causal models, to delineate the influence of patient and tumor characteristics on postoperative kidney function. Results: We determined that a significant interaction between age and tumor size (P=0.03) led to the observed inverse association between large tumor size and CKD upstaging, and was accentuated by other forms of selection bias. Subgrouping patients by age and tumor size demonstrated that all patients aged ≥65 years were at increased risk of CKD upstaging, regardless of tumor size. Risk of CKD upstaging was comparable between age-matched living donors and kidney cancer patients. Conclusion: Larger tumors are unlikely to confer a protective effect with respect to postoperative kidney function. The reason for the previously reported inconsistency is likely a combination of the analytical approach and selection bias.

Incident Chronic Kidney Disease After Radical Nephrectomy for Renal Cell Carcinoma

BACKGROUND

Chronic kidney disease (CKD) after surgery for kidney cancer is common, and is associated with increased morbidity and mortality. This study aimed to identify factors associated with incident CKD in patients managed with radical nephrectomy.

PATIENTS AND METHODS

All patients diagnosed with renal cell carcinoma between January 2012 and December 2013 were ascertained from state-based cancer registries in Queensland and Victoria. Information on patient, tumor, and health service characteristics was obtained via chart review. Multivariable logistic regression was used to evaluate exposures associated with incident CKD (estimated glomerular filtration rate [eGFR] <60 mL per minute per 1.73 m²) at 12 months after nephrectomy.

RESULTS

Older age (adjusted odds ratio [aOR] per 5-year increase, 1.5; 95% confidence interval [CI], 1.4-1.6), male sex (aOR, 1.4; 95% CI, 1.0-2.0), obese compared with not obese (aOR, 1.8; 95% CI, 1.2-2.7), rural compared with urban place of residence (aOR, 1.8; 95% CI, 1.1-3.0) were associated with a higher risk of incident CKD. Lower preoperative eGFR was also associated with a higher risk of incident CKD. Management in private compared with public hospitals was also associated with a higher risk of CKD (aOR, 1.6; 95% CI, 1.2-2.2). Factors related to tumor size and cancer severity were also associated with worse postoperative kidney function, although it is likely this was a consequence of selection bias.

CONCLUSION

Patient characteristics have the strongest associations with incident CKD after radical nephrectomy. Potential risk factors were reasonably similar to recognized CKD risk factors for the general population. Patients who undergo nephrectomy who have CKD risk factors might benefit from ongoing postoperative screening for deterioration of kidney function.

Chronic kidney cortical damage is associated with baseline kidney function and albuminuria in patients managed with radical nephrectomy for kidney tumours

This study evaluated the relationship between histological markers of chronic kidney damage in patients undergoing radical nephrectomy for kidney tumours and preoperative kidney function, degree of albuminuria, and changes in glomerular volume. A schema to grade chronic kidney damage could be used to identify patients at risk of developing CKD following nephrectomy. Non-neoplastic cortical tissue was sourced from 150 patients undergoing radical nephrectomy for suspected kidney cancer. This tissue was evaluated for indicators of chronic damage, specifically: glomerulosclerosis, arteriosclerosis, interstitial fibrosis, and tubular atrophy. Glomerular volume was determined using the Weibel and Gomez method. Associations between these parameters and both estimated glomerular filtration rate (eGFR) and albumin-creatinine ratio (ACR) were determined using either a Mann-Whitney U-test or a Kruskal-Wallis ANOVA. Associations between both eGFR and ACR and glomerular volume were assessed using linear regression. eGFR was inversely associated with the degree of glomerulosclerosis (p < 0.001), vascular narrowing (p = 0.002), tubular atrophy (p < 0.001), and interstitial fibrosis (p < 0.001). ACR was associated only with the degree of interstitial fibrosis (p = 0.02) and tubular atrophy (p = 0.02). Glomerular volume was greater for males, diabetics, hypertensive patients, and patients with a greater degree of interstitial fibrosis. Glomerular volume was positively associated with ACR. A schema to grade chronic damage was developed. The proposed schema is associated with baseline clinical indices of kidney function and damage. Longitudinal validation is necessary to determine the prognostic utility of this schema.

Predictors of new-onset chronic kidney disease in patients managed surgically for T1a renal cell carcinoma: An Australian population-based analysis

BACKGROUND

New-onset chronic kidney disease (CKD) following surgical management of kidney tumors is common. This study evaluated risk factors for new-onset CKD after nephrectomy for T1a renal cell carcinoma (RCC) in an Australian population-based cohort.

METHODS

There were 551 RCC patients from the Australian states of Queensland and Victoria included in this study. The primary outcome was new-onset CKD (eGFR <60 mL/min per 1.73 m² ) and the secondary outcome was new-onset moderate-severe CKD (<45 mL/min per 1.73 m² ). Multivariable logistic regression was used to evaluate associations between patient, tumor and health-service characteristics and these outcomes.

RESULTS

Forty percent (219/551) of patients developed new-onset CKD, and 12% (68/551) experienced new-onset moderate-severe CKD. Risk factors for new-onset CKD were age, lower preoperative eGFR, tumor size >20 mm, radical nephrectomy, lower hospital caseloads (<20 cases/year), and rural place of residence. The associations between rural place of residence and low center volume were a consequence of higher radical nephrectomy rates.

CONCLUSION

Risk factors for CKD after nephrectomy generally relate to worse baseline health, or likelihood of undergoing radical nephrectomy. Surgeons in rural centres and hospitals with low caseloads may benefit from formalized integration with specialist centers for continued professional development and case-conferencing, to assist in management decisions.

Eligibility for phase 3 clinical trials of systemic therapy in real-world patients with metastatic renal cell cancer managed in a rural region

Previous research has identified disparities between urban and rural cancer care, including clinical trial access. Therefore, we addressed three different questions in patients with metastatic renal cell cancer managed according to national guidelines in a rural Norwegian standard practice setting. (1) How many patients would have been eligible for three recent landmark randomized clinical trials? (2) Is survival different between eligible and non-eligible patients receiving first-line systemic therapy? (3) Is survival different between eligible patients and published trial results? We performed a retrospective analysis of 101 consecutive patients (2006-2016). Only 52% of the patients were eligible for the first-line study of pazopanib versus sunitinib. The main reasons for violating inclusion or exclusion criteria were presence of brain metastases, absence of clear cell histology, and poor performance status. Even fewer patients were eligible for trials of nivolumab and cabozantinib in pre-treated patients. Eligible patients had significantly better survival than non-eligible patients, median 29.2 versus 8.5 months (p = 0.0001). These results confirm that many patients from rural practices do not fulfill all mandatory trial eligibility criteria. However, eligible patients managed according to national guidelines had survival outcomes in line with published first-line trial results.

Pazopanib in Metastatic Renal Cancer: A "Real-World" Experience at National Cancer Institute "Fondazione G. Pascale"

Pazopanib is an oral angiogenesis inhibitor, currently approved for treatment of metastatic renal cell carcinoma (mRCC) and soft tissue sarcoma. The present study analyzed the outcomes of pazopanib in first-line treatment of mRCC, in a single Italian cancer center. In the light of the retrospective, observational nature and the unselected population, our experience can be defined a "real-world" study. The medical records of 38 mRCC patients treated with front-line pazopanib were retrospectively reviewed and analyzed. The progression free survival (PFS) and the overall survival (OS) were the primary endpoints, while secondary objectives included objective response rate (ORR), disease control rate (DCR), and treatment tolerability. Pazopanib achieved a median PFS (mPFS) of 12.7 months (95% CI, 6.9-18.5 months). The median OS (mOS) was 26.2 months (95% CI, 12.6-39.9 months); the observed ORR and DCR were 30.3 and 72.7%, respectively, with a median duration of response of 11 weeks. mPFS appeared not to be influenced by number of co-morbidities (< 3 vs. ≥3), gender, Fuhrman grade and age. Conversely, the ORR and the DCR positively affect the mPFS (HR = 0.05 [95% CI, 0.05-0.55], p = 0.01; HR = 0.10 [95% CI, 0.02-0.43], p = 0.002, respectively). A worse outcome was associated with a lower mPFS in patients with liver metastases (p = 0.2) and with a high tumor burden (number of metastatic sites < 6 vs. ≥6) (p = 0.08). Worst OS was observed in patients aged ≥70 years old (HR = 6.91 [95% CI, 1.49-31.91], p = 0.01). The treatment was well-tolerated: no grade 4 adverse events, nor discontinuation due to toxicities was reported. Grade 3 hypertension affected positively the OS reaching the statistical significance (HR = 0.22 [95% CI, 0.05-0.8], p = 0.03). Thyroid dysfunction (hypo and hyperthyroidism) seems to correlate with better outcome in terms of a longer mPFS (HR = 0.12 [95% CI, 0.02-0.78], p = 0.02). Our results are consistent with those reported in prospective phase III trials and the published retrospective "real world" experiences. This analysis confirms the safety and efficacy of pazopanib in first-line setting, both in frail patients with multiple co-morbidities and Karnofsky PS < 80% and in younger, healthier patients with a number of metastatic sites < 6.

Treatment patterns and clinical outcomes in patients with renal cell carcinoma in the UK: insights from the RECCORD registry

BACKGROUND

The aim of the RECCORD registry was to gather real-world UK data on the use of targeted therapies in renal cell carcinoma (RCC) and assess clinical outcomes. Here, demographic and outcome data are presented with the treatment patterns and demographic profile of patients on the registry.

PATIENTS AND METHODS

Patients were retrospectively identified at seven UK hospitals with large cancer centres in England (5), Scotland (1) and Wales (1). Anonymised data were collected through an online registry covering demographics, treatments and outcomes. Five hundred and fourteen UK adult patients with metastatic RCC were included in the study for analysis. Patients were included if they were treated for metastatic RCC at one of the seven centres, and started systemic anti-cancer treatment from March 2009 to November 2012 inclusive. In addition to demographic factors, the principal outcome measures were overall survival (OS), time to disease progression and toxicity.

RESULTS

The majority of first-line treatment was with sunitinib; first-line use of pazopanib increased as the study progressed. 15.8% of patients received second-line treatment, half of whom were prescribed everolimus. Median OS (from initiation of first-line treatment) was 23.9 months (95% confidence interval [CI] 18.6-29.1 months), similar to that reported for clinical trials of targeted RCC therapies [Ljungberg B, Campbell SC, Choi HY et al. The epidemiology of renal cell carcinoma. Eur Urol 2011; 60: 615-621; Abe H, Kamai T. Recent advances in the treatment of metastatic renal cell carcinoma. Int J Urol 2013; 20: 944-955; Motzer RJ, Hutson TE, Tomczak P et al. Overall survival and updated results for sunitinib compared with interferon alfa in patients with metastatic renal cell carcinoma. J Clin Oncol 2009; 27: 3584-3590]. OS was significantly longer for those who received second-line treatment after disease progression (33.0 months; 95% CI 30.8-35.2 months) than those who did not (20.9 months; 95% CI 16.4-25.3 months; P = 0.008).

CONCLUSIONS

RECCORD is a large 'real-world' database assessing metastatic RCC treatment patterns and outcomes. Treatment patterns changed over time as targeted therapies were approved and became widely available; survival data in RECCORD are consistent with those reported for systemic treatments in clinical trials. Kaplan-Meier analysis of results demonstrated that receiving second-line therapy was a major prognostic factor for longer OS.

National nephrectomy registries: Reviewing the need for population-based data

Nephrectomy is the cornerstone therapy for renal cell carcinoma (RCC) and continued refinement of the procedure through research may enhance patient outcomes. A national nephrectomy registry may provide the key information needed to assess the procedure at a national level. The aim of this study was to review nephrectomy data available at a population-based level in Australia and to benchmark these data against data from the rest of the world as an examination of the national nephrectomy registry model. A PubMed search identified records pertaining to RCC nephrectomy in Australia. A similar search identified records relating to established nephrectomy registries internationally and other surgical registries of clinical importance. These records were reviewed to address the stated aims of this article. Population-based data within Australia for nephrectomy were lacking. Key issues identified were the difficulty in benchmarking outcomes and no ongoing monitoring of trends. The care centralization debate, which questions whether small-volume centers provide comparable outcomes to high-volume centers, is ongoing. Patterns of adherence and the effectiveness of existing protocols are uncertain. A review of established international registries demonstrated that the registry model can effectively address issues comparable to those identified in the Australian literature. A national nephrectomy registry could address deficiencies identified in a given nation's nephrectomy field. The model is supported by evidence from international examples and will provide the population-based data needed for studies. Scope exists for possible integration with other registries to develop a more encompassing urological or surgical registry. Need remains for further exploration of the feasibility and practicalities of initiating such a registry including a minimum data set, outcome indicators, and auditing of data.