T1a Renal Cell Carcinoma Research Articles

Prognostic significance of subclassifying stage pT3a renal tumors with fat invasion: a retrospective study of 99 patients.

PurposeTo analyze the recurrence in patients with clinic stage T1 renal cell carcinoma (RCC) who were upstaged to stage T3a after partial nephrectomy (PN) using a new sub-classification criterion.MethodsA retrospective study of pathological characteristics was performed in patients who were upstaged to pT3a on the basis of fat invasion (FI).ResultsAfter analyzing the pathological findings, we proposed the following new sub-classification criteria for pT3a RCC with FI: (1) renal tumor invades the pseudo-capsule and contacts the perinephric adipose tissue directly or the tumor protrudes into the perinephric adipose tissue like a tongue (Type A); and (2) tumor nodules are distributed in perinephric adipose tissues (Type B). A significant difference was observed in the recurrence rate between the two subtypes A and B. For Type B, the recurrence rate after radical nephrectomy (RN) and PN was 15.79% and 63.64%, respectively. The recurrence rates for Types A and B after PN were 11.11% and 63.64%, respectively.ConclusionsT3a RCC with tumor nodules in perinephric adipose and/or an irregular tumor protruding into the adipose tissues lead to a higher recurrence rate. We recommend that T3a RCC be carefully analyzed and patients be treated on an individual basis.

Long-term outcomes of CT-guided percutaneous cryoablation of T1a and T1b renal cell carcinoma

PURPOSE We aimed to evaluate the long-term outcomes of computed tomography-guided percutaneous cryoablation (PCA) for biopsy-confirmed renal cell carcinoma (RCC). METHODS This was a single-center, retrospective study investigating all patients treated with PCA between January 2010 and February 2019 for RCC tumors. Primary outcome measures included overall survival (OS), disease-free survival (DFS), progression-free survival (PFS) and cancer-specific survival (CSS). Secondary outcome measures included kidney function, complications, technical success, hospital stay, procedural time, and the identification of factors affecting the primary outcomes. RESULTS Fifty-three consecutive patients with 54 lesions (T1a: 49/54; T1b: 5/54) were included. Mean tumor diameter was 28.0±8.5 mm and mean R.E.N.A.L. score was 7.2±2.0. Technical success was 100% (54/54 lesions) after two reinterventions for incomplete ablation. Mean follow-up time was 46.7±28.6 months (range, 3-122 months). Local recurrence was noted in 5 patients (9.2%). According to Kaplan-Meyer analysis, OS was 98.2%, 94.2%, 71.2%, and 58.2% at 1, 3, 5, and 8 years. One patient (1.9%) died of cancer and CSS was 95.8% at 8 years. DFS was 100.0%, 95.5%, and 88.6%, and PFS was 100%, 94.3%, and 91.0%, at 1, 2, and 5 years. Clavien-Dindo grade II complication rate was 7.8% (5/64 procedures). There were no complications classified as grade III or greater. Mean creatinine increase was 7.1±6.3 μm/L (p = 0.31). No patient advanced to dialysis during follow up. Mean procedural time was 163±45 min. Median hospital stay was 2.0 days (IQR, 1-2.5 days). Diabetes was the only independent predictor of decreased OS (hazard ratio 4.3, 95% CI 0.043-0.914; p = 0.038). CONCLUSION PCA for stage T1a and T1b RCC provides favorable long-term oncological and renal function preservation outcomes, with acceptable complication rates.

Delayed surgery for localised and metastatic renal cell carcinoma: a systematic review and meta-analysis for the COVID-19 pandemic.

PurposeThe COVID-19 pandemic has led to the cancellation or deferment of many elective cancer surgeries. We performed a systematic review on the oncological effects of delayed surgery for patients with localised or metastatic renal cell carcinoma (RCC) in the targeted therapy (TT) era.MethodThe protocol of this review is registered on PROSPERO(CRD42020190882). A comprehensive literature search was performed on Medline, Embase and Cochrane CENTRAL using MeSH terms and keywords for randomised controlled trials and observational studies on the topic. Risks of biases were assessed using the Cochrane RoB tool and the Newcastle–Ottawa Scale. For localised RCC, immediate surgery [including partial nephrectomy (PN) and radical nephrectomy (RN)] and delayed surgery [including active surveillance (AS) and delayed intervention (DI)] were compared. For metastatic RCC, upfront versus deferred cytoreductive nephrectomy (CN) were compared.ResultsEleven studies were included for quantitative analysis. Delayed surgery was significantly associated with worse cancer-specific survival (HR 1.67, 95% CI 1.23–2.27, p < 0.01) in T1a RCC, but no significant difference was noted for overall survival. For localised ≥ T1b RCC, there were insufficient data for meta-analysis and the results from the individual reports were contradictory. For metastatic RCC, upfront TT followed by deferred CN was associated with better overall survival when compared to upfront CN followed by deferred TT (HR 0.61, 95% CI 0.43–0.86, p < 0.001).ConclusionNoting potential selection bias, there is insufficient evidence to support the notion that delayed surgery is safe in localised RCC. For metastatic RCC, upfront TT followed by deferred CN should be considered.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00345-021-03734-1.

Outcomes of Percutaneous Thermal Ablation for Biopsy-Proven T1a Renal Cell Carcinoma in Patients With Other Primary Malignancies.

OBJECTIVE. The purpose of this article is to investigate the oncologic effectiveness and survival outcomes of percutaneous image-guided thermal ablation for clinical T1a renal cell carcinoma (RCC) in patients with other primary nonrenal malignancies. MATERIALS AND METHODS. We reviewed records of patients with histologically proven T1a RCC (< 4.0 cm) treated with thermal ablation over a period of 10 years between January 2005 and December 2014. We recorded past or current history of primary malignancy other than RCC, status of the primary malignancy, tumor histology (in remission or under therapy), and whether patient was currently alive or not, and if not, the date and reason of death. Three cohorts were studied: patients with RCC only (group A), patients with RCC and other primary malignancy in remission (group B), and patients with RCC and other primary malignancy under treatment (group C). The Kaplan-Meier product-limit estimator was used to estimate the survival rates. RESULTS. One hundred nine patients met the inclusion criteria (109 lesions, 110 ablation procedures). There were 46, 45, and 18 patients in the A, B, and C groups, respectively. The 5-year survival was 87%, 63%, and 40% for groups A, B, and C, respectively. The local recurrence-free survival for the whole sample was 95% at 3, 5, and 10 years. The disease-free survival was 96%, 93%, and 91% at 3, 5, and 10 years. Although a significant difference is noted between the three cohorts in overall survival (p = .02); for RCC, there were no significance differences in the local recurrence-free, disease-free, metastasis-free, and cancer-specific survivals. In addition, there was no difference in outcomes for patients in group B (in remission) when compared with those in group C (under treatment). CONCLUSION. Thermal ablation is an effective and safe modality of treatment of T1a RCC in patients with other primary malignancies that are in remission or under treatment.

Abstract No. 587 Magnetic resonance imaging–guided cryoablation of de novo solitary pathologically proven T1a renal tumors

To evaluate the long-term oncologic efficacy and survival rates of MRI-guided cryoablation ablation (PCA) for pathologically proven T1a Renal cell carcinoma (RCC). we retrospectively reviewed our renal ablation data base between January 2007 and December 2019, we included only patients with solitary de novo histologically diagnosed T1a RCC (≤4 cm) who underwent MRI-guided Cryoablation. Patient with recurrent or bilateral RCC, genetic syndromes, patient not pathologically proven to be RCC (benign lesions or nondiagnostic) and patients who underwent CT-guided cryoablation or Radiofrequency ablation were excluded. For each patient, we recorded: Demographics, tumor size and histology, complications, recurrence at ablation site, development of metastases, history of another malignancy, survival/death and cause of death. survival outcome were estimated using Kaplan and Meier product-limit estimator. Twenty-three MRI-guided procedures were performed for 23 lesions in 23 patients (13 males and 10 females, average age 70 years (50–92 years). Average tumor size was 2.1cm (range, 1–3.4 cm). The average follow-up for all subjects was 3.6 years (range: 0.18–9.73 years). Only 1 patient (4.3%) developed grade III complication according to the Clavien-Dindo classification. The most common pathology was clear cell RCC (n = 17) and 6 lesions were papillary RCC. Furhman grading was obtained in 21 lesion (grade I = 5 and grade II = 16) None of the patients developed local recurrence at the ablation site, elsewhere in the kidneys or metastasis from RCC. Fifteen patients had another primary malignancy other than RCC. The local recurrence free-, Disease free-, Metastasis free- and cancer specific survival (CSS) were 100 %. MRI-guided cryoablation is a safe and highly efficacious modality for treatment of small renal tumors. Long-term follow-up data reveals long standing oncologic control with low complication rate.

Partial nephrectomy provides equivalent oncologic outcomes and better renal function preservation than radical nephrectomy for pathological T3a renal cell carcinoma: A meta-analysis.

ABSTRACTPurpose:Radical nephrectomy (RN) is the standard surgical type for pathological stage T3a (pT3a) renal cell carcinoma (RCC). Recently, some studies have suggested equivalence between partial nephrectomy (PN) and RN for oncologic control and have shown the benefits of PN for better renal function. We conducted this meta-analysis to assess oncologic outcomes, perioperative outcomes and renal function between two groups among patients with pT3a RCC.Materials and methods:PubMed, Scopus, Web of Science, Science Direct, Ovid MEDLINE, The Cochrane Library, Embase and Google Scholar were searched for eligible articles. The endpoints of the final analysis included overall survival (OS), cancer-specific survival (CSS), recurrence-free survival (RFS), surgical complications, operative time, estimated blood loss (EBL), serum creatinine and estimated glomerular filtration rate (eGFR).Results:Twelve studies of moderate to high quality, including 14.152 patients, were examined. PN showed superiority for renal functional preservation, providing higher eGFR (WMD=12.48mL/min; 95%CI: 10.28 to 14.67; P <0.00001) and lower serum creatinine (WMD=-0.31mg/dL; 95%CI: −0.40 to −0.21; P <0.00001). There were no significant differences between PN and RN regarding operative time, EBL, surgical complications, OS, RFS and CSS. Despite inherent selection bias, most pooled estimates were consistent in sensitivity analysis and subgroup analysis. More positive margins were found in the PN group (RR=2.42; 95%CI: 1.25-4.68; P=0.009).Conclusions:PN may be more suitable for treating pT3a RCC than RN because it provides a similar survival time (OS or RFS) and superior renal function. Nevertheless, this result is still disputed, and more high-quality studies are required.

Effect of iodinated contrast material on post-operative eGFR when administered during renal mass ablation.

To evaluate the effect of intravenous iodinated contrast on estimated glomerular filtration rate (eGFR) when administered immediately after thermal ablation of clinically localized T1a (cT1a) renal cell carcinoma (RCC). This HIPAA-compliant, dual-center retrospective study was performed under a waiver of informed consent. Three hundred forty-two consecutive patients with cT1a biopsy-proven RCC were treated with percutaneous ablation between January 2010 and December 2017. Immediate post-ablation contrast-enhanced CT was the routine standard of care at one institution (contrast group), but not the other (control group). One-month pre- and 6-month post-ablation eGFR were compared using the Wilcoxon signed-rank test or the Kruskal-Wallis test. Multivariate linear regression was used to determine the effect of contrast on eGFR. A 1:1 propensity score matching was performed for all patients with a logistic model using patient, tumor, and procedural covariates. In total, 246 patients (158 M; median age 69 years, IQR 62-74) were included. Median tumor diameter (2.4 vs 2.5, p = 0.23) and RENAL nephrometry scores (6 vs 6, p = 0.92), surrogates for ablation zone size, were similar. Baseline kidney function was similar for the control and contrast groups, respectively (median eGFR: 70 vs 74 mL/min/1.73 m2, p = 0.29). There was an expected mild decline in eGFR after ablation (control: 70 vs 60 mL/min/1.73 m2, p < 0.001; contrast: 75 vs 71 mL/min/1.73 m2, p = 0.001). Intravenous iodinated contrast was not associated with a decline in eGFR on multivariate linear regression (1.91, 95% CI - 3.43-7.24, p = 0.46) or 1:1 propensity score-matched model (- 0.33, 95% CI - 6.81-6.15, p = 0.92). Intravenous iodinated contrast administered during ablation of cT1a RCC has no effect on eGFR. • Intravenous iodinated contrast administered during thermal ablation of clinically localized T1a renal cell carcinoma has no effect on kidney function. • Thermal ablation of clinically localized T1a renal cell carcinoma results in a mild decline in kidney function. • A decline in kidney function is similar for radiofrequency and microwave ablation of clinically localized T1a renal cell carcinoma.

Prognostic Evaluation of the Site of Invasion in Pathological Stage T3a Renal Cell Carcinoma.

To investigate the prognostic values of fat invasion (FI) and renal vein invasion (RVI) in pT3a renal cell carcinoma (RCC), as single factors or concomitant presence. We retrospectively reviewed the data of 173 patients who underwent radical or partial nephrectomy for RCC in our Institution. At a median follow-up time of 48 months, patients with RVI showed significantly increased risk of disease recurrence and worse cancer-specific survival (CSS) when compared to those with FI (p=0.007, p=0.022, respectively). Having combined RVI and FI did not show inferior prognosis compared to those with RVI only. In multivariable analysis, RVI was an independent factor for disease recurrence (HR=2.06, 95% CI=1.10-3.87, p=0.024) and CSS (HR=2.46, 95% CI=1.01-6.0, p=0.048). For patients with T3a renal tumors, RVI was associated with inferior prognosis compared to those with FI.

Efficacy and safety of CT-guided microwave ablation for stage T1a renal cell carcinoma in patients with a solitary kidney

Objective To retrospectively evaluate early clinical outcomes of percutaneous microwave ablation (MWA) for stage T1a renal cell carcinomas (RCCs) in solitary kidney patients. Materials and methods 15 solitary kidney patients with 16 stage T1a N0M0 biopsy-proved RCCs underwent CT-guided percutaneous microwave ablation between October 2016 and July 2020. The patients were followed up with contrast-enhanced computed tomography or magnetic resonance imaging at 1, 3, and 6 months and every 6 months thereafter. Serum creatinine levels of each patient pre MWA, 1 day after MWA and the most recent record were collected. Technical effectiveness, local recurrence, survival rates and complications were accessed. Results Complete ablation was achieved in all 16 tumors (100%) including 13 clear cell carcinomas and 3 papillary carcinomas. Within the follow-up time (median: 24 months) no tumor recurrence or major complication was detected. No significant change in serum creatinine level was noted. The cancer-specific survival rate was 100% (15 of 15), and 1-, 2-, and 3-year overall survival rates were 100%, 93.3%, and 93.3%, respectively. Conclusion Percutaneous MWA is an effective and safe treatment option for stage T1a RCCs in solitary kidney patients; it can achieve high complete ablation rate in selected lesions of appropriate size and location.

The critical impact of tumor size in predicting cancer special survival for T3aM0M0 renal cell carcinoma: A proposal of an alternative T3aN0M0 stage.

ObjectiveBased on the eighth TNM staging system, T3a renal cell carcinoma (RCC) is identified as an anatomical extrarenal invasion and does not consider the size of the tumor; however, it may not fully predict the prognosis of the patient. The objective of this study was to evaluate the prognostic value of tumor size effects on prognosis in T3a RCC and propose an alternative tumor stage system combined with T1‐2.MethodsData relating to T1‐3aN0M0 RCC (n = 49586) were obtained from the Surveillance, Epidemiology, and End Results database (2004–2015). Survival analyses were conducted by Cox regression and Fine and Gray regression. Harrell's concordance index (c‐index) was used to assess the discriminatory ability of the prognostic factors.ResultsA 1‐cm increase in T3a RCC resulted in an 8% increase in all‐cause mortality (hazard ratio [HR]: 1.08; 95% confidence interval [CI]: 1.06–1.10, p < 0.001) and 14% increase in the risk of RCC‐specific mortality (sub‐distribution HR [sHR]: 1.14; 95% CI: 1.11–1.16, p < 0.001). T3a tumor size stratified by the cutoff of 4 cm and 7 cm showed a better prediction of RCC‐special survival (c‐index: 0.644), compared with a cutoff just by 4 cm (c‐index: 0.571) or by 7 cm (c‐index: 0.602). Compared with T1b tumors, T3a RCC ≤4 cm showed no differences in terms of all‐cause mortality (HR: 0.93; 95% CI: 0.79–1.09; p = 0.37) and mortality caused by RCC (sHR: 0.91; 95% CI: 0.70–1.19; p = 0.50). Last, the alternative T‐staging system (T1a, a combination of T1b and T3a [≤4 cm], T2a, T2b, T3a [4–7 cm], and T3a [>7] cm) demonstrated good RCC‐special survival predictive accuracy (c‐index: 0.729), which was higher than that shown by the current eighth edition T‐staging system (c‐index: 0.720).ConclusionTumor size should be taken into consideration for T3aN0M0 RCC rather than based on anatomical features alone.

Utilization of a three-dimensional printed kidney model for favorable TRIFECTA achievement in early experience of robot-assisted partial nephrectomy.

BackgroundThis retrospective study aimed to investigate whether a three-dimensional (3D) model would improve the achievement of TRIFECTA, which was defined as the absence of perioperative complications and positive surgical margins and a warm ischemia time of <25 minutes, during robot-assisted partial nephrectomy (RAPN).MethodsPrior to RAPN, a 3D-square type kidney model was prepared and used for all RAPN procedures in patients with T1a renal cell carcinoma (RCC) treated at a single center between March 2016 and April 2019. All RAPN procedures were performed by a single surgeon.ResultsThe study included 50 patients, of whom 22, 24, and 4 had low-, intermediate-, and high-risk R.E.N.A.L Nephrometry scores, respectively. The TRIFECTA achievement rate was 86.0%, and transfusion or conversion to radical nephrectomy was not required in any of the patients. Only one Clavien-Dindo grade 3 complication was reported—a pseudoaneurysm that required embolism. The TRIFECTA achievement rate was independent of the R.E.N.A.L Nephrometry scores and the surgeon’s experience level (25 cases each of early and advanced experience).ConclusionsThe 3D model contributed to the achievement of TRIFECTA during RAPN performed by a less-experienced surgeon. These findings should be further evaluated in studies involving a larger number of cases and surgeons.

Predictors of Recurrence for T3a RCC: A Recurring Conundrum.

Although the gold standard treatment for localized renal cell carcinoma (RCC) is radical nephrectomy (RN) or partial nephrectomy (PN), recurrence rates remain high at 7%, 26%, and 39% for T1, T2, and T3 staged disease, respectively [...].

Reply to "Predictors of Recurrence for T3a RCC: A Recurring Conundrum".

We really appreciate Leopold et al's thoughtful comments in response to our manuscript regarding the prognostic value of pT3 renal cell carcinoma (RCC)-related features [...].

Cost-Effectiveness of Radiofrequency Ablation (RFA) Versus Stereotactic Body Radiotherapy (SBRT) in the Treatment of Localized Renal Cell Carcinoma

Alternative organ preservation strategies for management of localized renal cell carcinoma (RCC) in patients unsuitable for surgery are increasingly being utilized, including radiofrequency ablation (RFA) and more recently stereotactic body radiotherapy (SBRT). We conducted a cost-effectiveness analysis of SBRT versus RFA. A Markov state transition model was constructed for initial local treatment with RFA or SBRT for early stage medically inoperable RCC, defined as node negative T1a/b (≤4 cm or 4-7 cm) lesions. In the model, hypothetical cohorts of early stage, biopsy proven, RCC patients with solitary, unilateral renal masses, and no evidence of distant metastases were created. Transition probabilities, health state utilities and costs used in the model were obtained through a comprehensive literature review of RFA and SBRT for early stage RCC. Incremental cost effectiveness ratios (ICER) were then calculated to compare the two treatments. The analysis was conducted over 5-year time horizon from the perspective of a publicly funded health system in Canada. Secondary analyses were conducted to assess effect of small versus large size (T1a versus T1b) RCC on ICERs. A one-way deterministic sensitivity analysis was conducted. Discounting of 5% was applied. Over 5 years, SBRT gained 4.2 QALYs at cost of $25,342 compared with 3.7 QALYs at cost of $27,634 for RFA. The ICER was $5,048 CAD per QALY in the base case analysis. In patients with small tumors (T1a), SBRT was $6,254 more expensive then RFA and was associated with an additional 0.42 QALYs (ICER $14,963). In patients with larger tumors (T1b), SBRT dominated RFA (i.e. $6,685 less expensive with an additional 0.54 QALYs). In the sensitivity analyses, the greatest potential influencers on cost-effectiveness were the rate of development of distant metastases (0.009-0.055 for SBRT and 0.003-0.025 for RFA) and utility values following both SBRT (0.75-0.85) and RFA (0.65-0.75). Overall, SBRT used as a primary treatment for RCC appears to be more effective at a marginal increase in cost compared with RFA. The use of SBRT appears to be cost-effective for larger tumors while for smaller tumors RFA may be more appropriate as an initial treatment strategy. Potential reasons for increased cost of RFA include equipment costs, costs for complications and admissions in comparison to SBRT> The validity of these conclusions are highly sensitive on the accuracy of local and distant progression rates reported in previous studies, and may be adjusted as the available data on SBRT and RFA continues to evolve and mature.

SC159 - Prognostic differences in patients with T1a renal cell carcinoma according to clinical size

SC159 - Prognostic differences in patients with T1a renal cell carcinoma according to clinical size

Gender Differences in the Clinical Management of clinical T1a Renal Cell Carcinoma

To evaluate gender differences in the management of clinical T1a (cT1a) renal cell carcinoma (RCC) before and after release of the AUA guidelines for management in 2009, which prioritized nephron-sparing approaches. Patients aged ≥66 years diagnosed with cT1a RCC from 2004 to 2013 in Surveillance, Epidemiology, and End Results-Medicare were analyzed. Multivariable mixed-effects logistic regression models were used to evaluate factors associated with radical nephrectomy (RN) for cT1a RCC before (2004 to 2009) and after (2010 to 2013) guidelines release. Predictors of pathologic T3 upstaging and high grade pathology in the postguidelines period were examined using multivariable logistic regression among patients who underwent RN or partial nephrectomy. Twelve thousand four hundred and two patients with cT1a RCC were identified, 42% of whom were women. Overall, the likelihood of RN decreased postguidelines (odds ratio [OR]=0.44, P <.001), but women were at increased odds of undergoing RN both before and after guideline release (OR=1.27, P <.001 and OR=1.37, P <.001, respectively) upon multivariable mixed-effects logistic regression. Tumor size >2 cm was also associated with increased likelihood of RN before and after guidelines (OR=2.61, P <.001 and OR=2.51, P <.001, respectively). In the postguidelines period, women had significantly lower odds of pathologic upstaging (OR=0.75, P=.024) and harboring high grade pathology (OR=0.71, P <.001) compared to men. Gender differences persist in the management of cT1a RCC, with women having higher odds of undergoing RN, even after release of AUA guidelines and despite having lower odds of pathologic upstaging and high-grade disease.

V084 - Thrombectomy and cavoraphy performed totally intracorporeal with a 3D laparoscopic approach in treating T3a and T3b renal cell carcinoma

V084 - Thrombectomy and cavoraphy performed totally intracorporeal with a 3D laparoscopic approach in treating T3a and T3b renal cell carcinoma

PT163 - Multicenter comparison of outcomes for clinical and pathologic T3a renal cell carcinoma

PT163 - Multicenter comparison of outcomes for clinical and pathologic T3a renal cell carcinoma

Percutaneous Microwave Ablation of Category T1a Renal Cell Carcinoma: Intermediate Results on Safety, Technical Feasibility, and Clinical Outcomes of 119 Tumors.

OBJECTIVE. The purpose of this study was to assess the safety, technical results, and clinical outcomes of CT-guided percutaneous microwave ablation of category T1a renal cell carcinoma. MATERIALS AND METHODS. This retrospective study investigated consecutive patients who underwent CT-guided microwave ablation for T1a renal cell carcinoma from October 2015 to May 2019. Patient demographics including tumor characteristics, comorbidities, technical details, and clinical outcomes were evaluated. Local progression-free survival and overall survival rates were estimated using the Kaplan-Meier method. RESULTS. One hundred-six patients including 70 men (mean age, 68.5 ± 8.9 [SD] years; range, 49-86 years) and 36 women (mean age, 69.5 ± 10.0 years; range, 50-88 years) with an overall mean age of 68.8 ± 9.2 years (range, 49-88 years) with 119 T1a renal cell carcinomas were treated with CT-guided microwave ablation. Technical success was achieved for 100% of the tumors. Complete response was achieved in 101 (95.3%) patients and partial response was achieved in five (4.7%) patients. Local progression-free survival was 100.0%, 92.8%, and 90.6% at 1, 2, and 3 years, respectively. Overall survival was 99.0%, 97.7%, and 94.6% at 1, 2, and 3 years, respectively. Six patients (5.7%) had seven complications (five with Clavien-Dindo Grade I, Society of Interventional Radiology [SIR] category A, two with Clavien-Dindo Grade III, SIR category B) within 30 days of the procedure. CONCLUSION. CT-guided percutaneous microwave ablation is associated with high rates of technical success, excellent local progression-free survival and overall survival, and a low complication rate for category T1a renal cell carcinoma.

Long-term outcomes after radical or partial nephrectomy for T1a renal cell carcinoma: A population-based study.

The benefit of partial nephrectomy (PN) compared to radical nephrectomy (RN) for T1a renal cell carcinoma (RCC) remains uncertain, with observational studies conflicting with level 1 evidence. Therefore, the purpose of this population-based study was to compare long-term outcomes in patients undergoing PN or RN for T1a RCC. We studied 5670 patients in Ontario, Canada undergoing PN or RN for T1a RCC. The primary outcome was overall survival (OS). Secondary outcomes were cancer-specific survival (CSS), chronic kidney disease (CKD), renal replacement therapy, and myocardial infarction (MI). We used multivariable Cox proportional hazard models to evaluate the association between PN or RN and these outcomes. A sensitivity analysis was performed in patients with a preoperative serum creatinine available. Median followup was 77 months. Compared to RN, PN was associated with significantly improved OS (hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.63-0.84), reduced risk of CKD (HR 0.18, 95% CI 0.12-0.27), and improved CSS (HR 0.45, 95% CI 0.30-0.65). The risk of MI was not significantly different between groups (HR 0.91, 95% CI 0.62-1.34). Few patients (n=15) required renal replacement therapy. In the sensitivity analysis, the association between type of surgery and OS and CKD persisted, while the association with CSS did not. Our study found that in patients undergoing surgery for T1a RCC, PN was associated with improved OS and reduced risk of CKD compared to RN. However, few patients in either group required renal replacement therapy.