Long-Term Oncologic Outcomes After Radiofrequency Ablation for T1 Renal Cell Carcinoma

Background

Radiofrequency ablation (RFA) of renal cell carcinoma (RCC) is used to obtain local control of small renal masses. However, available long-term oncologic outcomes for RFA of RCC are limited by small numbers, short follow-up, and lack of pathologic diagnoses.

Objective

To assess the oncologic effectiveness of RFA for the treatment of biopsy-proven RCC.

Design, setting, and participants

Exclusion criteria included prior RCC or metastatic RCC, familial syndromes, or T2 RCC. We retrospectively reviewed long-term oncologic outcomes for 185 patients with sporadic T1 RCC. Median follow-up was 6.43 yr (interquartile range [IQR]: 5.3–7.7).

Outcome measurements and statistical analysis

The chi-square test and Wilcoxon rank-sum tests were used to compare proportions and medians, respectively. Disease-specific survival and overall survival (OS) were calculated using Kaplan-Meier analysis, then stratified by tumor stage, and comparisons were made using log-rank analysis. The 5-yr disease-free survival (DFS) and OS rates are reported. A p value <0.05 was considered statistically significant.

Results and limitations

Median tumor size was 3 cm (IQR: 2.1−3.9 cm). Tumor stage was T1a: 143 (77.3%) or T1b: 42 (22.7%). Twenty-four patients (13%) were retreated for residual disease. There were 12 local recurrences (6.5%), 6 recurrences in T1a disease (4.2%) and 6 in T1b disease (14.3%) (p = 0.0196). Median time to recurrence was 2.5 yr. Local salvage RFA was performed in six patients, of whom five remain disease free at 3.8-yr median follow-up. Tumor stage was the only significant predictor of DFS on multivariate analysis. At last follow-up, 164 patients (88.6%) were disease free (T1a: n = 132 [92.3%]; T1b: n = 32 [76.2%]; p = 0.0038). OS was similar regardless of stage (p = 0.06). Five patients developed metachronous renal tumors (2.7%). Four patients developed extrarenal metastases (2.2%), three of whom died of metastatic RCC (1.6%).

Conclusions

In poor surgical candidates, RFA results in durable local control and low risk of recurrence in T1a RCC. Higher stage correlates with a decreased disease-free survival. Long-term surveillance is necessary following RFA. Patient selection based on tumor characteristics, comorbid disease, and life expectancy is of paramount importance.     

Feasibility of Robotic Laparoendoscopic Single-Site Partial Nephrectomy for Renal Tumors >4 cm

Background

Laparoendoscopic single-site (LESS) urologic procedures have gained significant interest worldwide in an attempt to further reduce morbidity and minimize scarring associated with conventional laparoscopic surgery. The robotic technology has overcome some of the limitations of manual single-incision surgery relating to lack of triangulation, instrument collision, and surgical exposure. There are no data on robotic LESS partial nephrectomy (PN) for renal tumors >4 cm.

Objectives

To evaluate the feasibility of robotic LESS PN for renal tumors >4 cm.

Design, setting, and participants

Data from 67 consecutive patients who underwent robotic LESS PN were collected between May 2009 to January 2011.

Outcome measurements and statistical analysis

Patients were stratified into two groups: 20 patients with renal tumors >4 cm (group 1) and 47 patients with renal tumors ≤4 cm (group 2). Perioperative data were recorded and comparisons between the two groups were analyzed using the Mann-Whitney U test for continuous variables and Fisher exact test for categorical variables.

Results and limitations

No statistically significant differences were found between the two groups in demographic information, operative complications, pathologic characteristics, mean decline in estimated glomerular filtration rate, estimated blood loss, operative times, conversion rate, or positive surgical margins. However, group 1 had a higher mean nephrometry score (p < 0.01), longer warm ischemia time (p = 0.007), and longer length of stay (p = 0.046). Its retrospective design and being conducted at a single center were the main limitations of this study.

Conclusions

This study demonstrated the feasibility and safety of robotic LESS PN for tumors >4 cm. Patients with tumors >4 cm had a statistically significant, higher mean nephrometry score, longer warm ischemia time, and longer length of stay, but there was no increased risk of adverse outcomes. A long-term study is needed to confirm the durable renal preservation and oncologic outcomes for patients with larger tumor burden.     

Robotic Partial Nephrectomy for Renal Tumors Larger Than 4 cm

Background

Minimally invasive partial nephrectomy (PN) is most commonly performed for renal tumors ≤4 cm in size. Robotic PN (RPN) for tumors >4 cm has not been assessed.

Objective

To evaluate the safety and feasibility of RPN for tumors >4 cm in the context of patients undergoing RPN for tumors ≤4 cm.

Design, setting, and participants

We reviewed data for 71 consecutive patients who underwent transperitoneal RPN at a tertiary care center between August 2007 and September 2009 by a single surgeon. Patients were stratified into two groups: 15 with tumors >4 cm on preoperative imaging (group 1) and 56 patients with tumors ≤4 cm (group 2).

Intervention

All patients underwent transperitoneal RPN by a single surgeon.

Measurements

Preoperative, perioperative, pathologic, and functional outcomes data were analyzed and compared between groups. We used χ² and student t tests for categorical and continuous variables, respectively. A p value <0.05 was considered statistically significant.

Results and limitations

Mean radiographic tumor size was 5.0 cm (4.1–7.9) for group 1 and 2.1 cm (0.7–3.8) for group 2. No significant differences were found between groups for estimated blood loss, total operative time, hospital stay, complication rates, and change in estimated glomerular filtration rate. Patients with larger tumors had longer median warm ischemia times (25 vs 20 min; p = 0.011). Limitations of our study include the retrospective nature the analysis, small sample size, and single-surgeon experience.

Conclusions

In our initial experience, RPN for tumors >4 cm is safe and feasible, showing comparable outcomes to RPN for smaller tumors, although with longer warm ischemia times. Future studies with extended follow-up are necessary to determine the viability of RPN for large tumors as an effective form of treatment.     

Every Minute Counts When the Renal Hilum Is Clamped During Partial Nephrectomy

Background

The safe duration of warm ischemia during partial nephrectomy remains controversial.

Objective

Our aim was to evaluate the short- and long-term renal effects of warm ischemia in patients with a solitary kidney.

Design, setting, and participants

Using the Cleveland Clinic and Mayo Clinic databases, we identified 362 patients with a solitary kidney who underwent open (n = 319) or laparoscopic (n = 43) partial nephrectomy using warm ischemia with hilar clamping.

Measurements

Associations of warm ischemia time with renal function were evaluated using logistic or Cox regression models first as a continuous variable and then in 5-min increments.

Results and limitations

Median tumor size was 3.4 cm (range: 0.7–18.0 cm), and median ischemia time was 21 min (range: 4–55 min). Postoperative acute renal failure (ARF) occurred in 70 patients (19%) including 58 (16%) who had a glomerular filtration rate (GFR) <15 ml/min per 1.73 m² within 30 d of surgery. Among the 226 patients with a preoperative GFR ≥ 30 ml/min per 1.73 m² and followed ≥30 d, 38 (17%) developed new-onset stage IV chronic kidney disease during follow-up. As a continuous variable, longer warm ischemia time was associated with ARF (odds ratio: 1.05 for each 1-min increase; p < 0.001) and a GFR < 15 (odds ratio: 1.06; p < 0.001) in the postoperative period, and it was associated with new-onset stage IV chronic kidney disease (hazard ratio: 1.06; p < 0.001) during follow-up. Similar results were obtained adjusting for preoperative GFR, tumor size, and type of partial nephrectomy in a multivariable analysis. Evaluating warm ischemia in 5-min increments, a cut point of 25 min provided the best distinction between patients with and without all three of the previously mentioned end points. Limitations include the retrospective nature of the study.

Conclusions

Longer warm ischemia time is associated with short- and long-term renal consequences. These results suggest that every minute counts when the renal hilum is clamped.     

Comparison of Warm Ischemia Versus No Ischemia During Partial Nephrectomy on a Solitary Kidney

Background

The safe duration of warm ischemia during partial nephrectomy (PN) remains controversial.

Objective

To compare the short- and long-term renal effects of warm ischemia versus no ischemia in patients with a solitary kidney.

Design, setting, and participants

Using the Cleveland Clinic and Mayo Clinic databases, we identified 458 patients who underwent open (n = 411) or laparoscopic (n = 47) PN for a renal mass in a solitary kidney between 1990 and 2008. Patients treated with cold ischemia were excluded.

Measurements

Associations of ischemia type (none vs warm) with short- and long-term renal function were evaluated using logistic or Cox regression models.

Results and limitations

No ischemia was used in 96 patients (21%), while 362 patients (79%) had a median of 21 min (range: 4–55) of warm ischemia. Patients treated with warm ischemia had a significantly higher preoperative glomerular filtration rate (GFR; median: 61 ml/min per 1.73 m² vs 54 ml/min per 1.73 m²; p < 0.001) and larger tumors (median: 3.4 cm vs 2.5 cm; p < 0.001) compared with patients treated with no ischemia. Warm ischemia patients were significantly more likely to develop acute renal failure (odds ratio [OR]: 2.1; p = 0.044) and a GFR <15 ml/min per 1.73 m² in the postoperative period (OR: 4.2; p = 0.007) compared with patients who did not have hilar clamping. Among the 297 patients with a preoperative GFR ≥30 ml/min per 1.73 m², patients with warm ischemia were significantly more likely to develop new-onset stage IV chronic kidney disease (hazard ratio: 2.3; p = 0.028) during a mean follow-up of 3.3 yr. Similar results were obtained adjusting for preoperative GFR, tumor size, and type of PN in a multivariable analysis. Limitations include surgeon selection bias when determining type of ischemia.

Conclusions

Warm ischemia during PN is associated with adverse renal consequences. Although selection bias is present, PN without ischemia should be used when technically feasible in patients with a solitary kidney.     

Recovery of Renal Function After Open and Laparoscopic Partial Nephrectomy

Background

Although oncologic outcomes appear to be similar after laparoscopic partial nephrectomy (LPN) and open partial nephrectomy (OPN), data on renal function are lacking.

Objective

To evaluate the change over time in renal function after LPN and OPN.

Design, setting, and participants

We identified 987 patients with a single sporadic tumor and a normal contralateral kidney who were treated by LPN (n = 182) and OPN (n = 805) between January 2002 and July 2009.

Intervention

All patients underwent LPN or OPN at Memorial Sloan-Kettering Cancer Center.

Measurements

Estimated glomerular filtration rate (GFR) was calculated using the abbreviated Modification of Diet in Renal Disease formula. We created a multivariable generalized estimating equations linear model that predicted GFR based on the time from surgery, preoperative GFR, tumor size, American Society of Anesthesiologists score, and ischemia time.

Results and limitations

Mean patient age, tumor size, and ASA score were similar between LPN and OPN patients. The baseline preoperative GFR was lower in the laparoscopic group (67 ml/min per 1.73 m² vs 73 ml/min per 1.73 m²; p < 0.001). The mean ischemia time was shorter after LPN than OPN (35 min vs 40 min, respectively; p < 0.001). In a multivariable model, the interaction term between time from surgery and approach was statistically significant (p = 0.045), indicating that there was a differential effect on recovery of renal function over time by approach. Laparoscopically treated patients maintained a slightly higher renal function than those treated via an open approach. The 2-mo and 6-mo predicted GFR for a typical patient increased slightly from 65 ml/min per 1.73 m² to 67 ml/min per 1.73 m², respectively, for those treated laparoscopically but remained constant at 62 ml/min per 1.73 m² after OPN.

Conclusions

Our data suggest that the surgical approach has a small effect on the recovery of renal function after partial nephrectomy. Laparoscopically treated patients maintained slightly higher renal function.     

Feasibility of Transvaginal NOTES-Assisted Laparoscopic Nephrectomy

Background

Recently, the feasibility of a transvaginal hybrid natural orifice transluminal endoscopic surgery (NOTES) nephrectomy was demonstrated in a 23-yr-old woman with a nonfunctional atrophic kidney.

Objective

To evaluate the feasibility and reproducibility of transvaginal NOTES-assisted laparoscopic nephrectomy in female patients with and without renal cancer.

Design, setting, and participants

Between March 2008 and June 2009, 14 female patients were submitted to transvaginal NOTES-assisted laparoscopic nephrectomy for T1–T3a N0M0 renal cancer (n = 10), lithiasis (n = 2), or renal atrophy (n = 2) at the Hospital Clinic of Barcelona, Spain.

Surgical procedure

Under general anaesthesia, female patients underwent laparoscopic nephrectomy by transvaginal NOTES using a deflectable camera by vaginal access and two additional 5- and 10-mm trocars in the abdomen. The renal artery and vein were dissected and taken separately between clips. The dissected kidney was removed via the vagina after enlarging the vaginal trocar incision.

Measurements

All data referring to patient demographics, surgery, pathology, and perioperative outcomes were recorded.

Results and limitations

The procedure was completed in all patients. The mean age of the women was 59.1 yr. The mean operative time was 132.9 min and the mean estimated blood loss was 111.2 ml. None of the patients required a blood transfusion and the use of analgesics was low. The mean hospital stay was 4 d. In one case, a major complication (a colon injury) occurred. The patient underwent surgery and a temporary colostomy was performed. The patient has already undergone reconstruction.

Conclusions

Transvaginal NOTES-assisted laparoscopic nephrectomy is feasible and reproducible and may be an alternative technique for treatment of women with renal cancer. Proper selection of patients is warranted for success of this new approach. However, longer follow-up in an increasing number of patients is needed to establish its role in the treatment of renal cancer.     

National treatment trends among older patients with T1-localized renal cell carcinoma

Objective

To assess the national trends in treatment of localized renal tumors among older patients with limited life expectancy.

Renal Tumor Contact Surface Area: A Novel Parameter for Predicting Complexity and Outcomes of Partial Nephrectomy

Background

The contact surface area (CSA) of a tumor with adjacent renal parenchyma may determine the complexity and thus the perioperative outcomes of partial nephrectomy (PN).

Objective

We devised a novel imaging parameter, renal tumor CSA, and correlate it with perioperative outcomes in patients undergoing PN.

Design, setting, and participants

Of 200 patients undergoing PN for a tumor (January 2010 to August 2011), 162 had renal protocol computed tomography scanning data available. CSA was calculated using image-rendering software (Synapse 3D, Fujifilm), and interobserver variability was determined between three independent observers.

Outcome measurements and statistical analysis

CSA was correlated to baseline demographics and perioperative outcomes as a continuous and categorical variable using multivariable logistic regression analysis. The ability of CSA to predict adverse perioperative events was compared with demographic factors and nephrometry scoring systems.

Results and limitations

The mean tumor size was 3.1 cm; CSA was 18.3 cm². CSA ≥20 cm² correlated with adverse tumor characteristics (greater tumor size, volume, and complexity) and perioperative outcomes (more parenchymal volume loss, blood loss, and complications) compared with CSA <20 cm². On multivariable logistic regression, CSA independently predicted operative time, complications, hospital stay, and renal functional outcomes. This predictive ability of CSA was superior to the other parameters evaluated.

Conclusions

CSA is a novel imaging parameter that quantifies the CSA of renal tumor with adjacent parenchyma. Our preliminary data indicate that CSA correlates with PN outcomes. If validated externally in a larger cohort, CSA could be incorporated into future versions of nephrometry scoring systems.

Patient summary

In this study we outline the method of calculating the contact surface area (CSA) of renal tumors with the surrounding normal kidney using image-rendering software. We found that CSA correlates with a number of important surgical outcomes including operative time, loss of renal function, and complications.     

Partial Nephrectomy Is Associated with Improved Overall Survival Compared to Radical Nephrectomy in Patients with Unanticipated Benign Renal Tumours

Background

Partial nephrectomy (PN) has been associated with improved overall survival (OS) in select cohorts with localised renal masses when compared to radical nephrectomy (RN). The driving forces behind these differences have been difficult to elucidate given the heterogeneity of previously compared cohorts.

Objective

Compare OS in a subset of patients with unanticipated benign renal masses to minimise the confounding effect of cancer.

Design, setting, and participants

We retrospectively evaluated 2608 consecutive clinical T1 enhancing renal masses that were treated with extirpative surgery at our institution between 1999 and 2006. Of these, 499 tumours (19%) were found to be benign on final pathology. Preoperative data and renal functional data were used to generate a propensity model that was then plugged into a multivariate model of survival. Median follow-up for the entire cohort was 50 mo (interquartile range [IQR]: 32–73).

Intervention

All patients underwent PN or RN.

Measurements

We measured OS and cardiac-specific survival.

Results and limitations

Five-year OS estimates for the PN (n = 388) and RN (n = 111) cohorts were 95% (95% confidence interval [CI], 93–98) versus 83% (95% CI, 74–90), respectively (P < 0.0001). On multivariate analysis, controlling for both comorbidity and age, RN was associated with a 2.5-fold increased risk of death compared to PN (hazard ratio [HR]: 2.5; 95% CI, 1.3–5.1). Postoperative estimated glomerular filtration rate (eGFR) was also an independent predictor of OS and cardiac-specific survival (HR: 0.97; 95% CI, 0.95–0.99 and HR: 0.96; 95% CI, 0.93–0.99, respectively). The retrospective nature of this analysis limits the strength of the conclusions.

Conclusions

PN was associated with better OS when compared to RN in patients with unanticipated benign tumours. This observed survival advantage appears partly to be the result of better preservation of eGFR, but other kidney functions or unmeasured factors may also play a role. These data indicate that PN should be aggressively pursued in any patient where PN is technically feasible.     

Laparoendoscopic Single-site Partial Nephrectomy Without Ischemia for Very Small,Exophytic Renal Masses: Surgical Details and Functional Outcomes

Background

Laparoendoscopic single-site surgery (LESS) has emerged as a natural progression from standard laparoscopy aiming to further minimize the morbidity of urologic procedures.

Objective

To describe our technique and report the surgical and functional outcomes of unclamped LESS partial nephrectomy (PN) in the treatment of small renal masses (SRMs).

Design, setting, and participants

Prospective evaluation of pre- and postoperative variables of patients undergoing the LESS-PN without ischemia between 2009 and 2012. The indications were single exophytic SRMs.

Surgical procedure

Unclamped LESS-PN was performed through a transperitoneal approach. A pararectal Hasson access technique was preferred. Single-port access was achieved via different single-port devices. A combination of straight and articulating laparoscopic instruments was used. The tumor was excised using bipolar scissors during normal renal perfusion. Hemostasis was achieved by bipolar electrocautery, parenchymal stitches, and hemostatic agents.

Outcome measurements and statistical analysis

Demographic, operative, postoperative, and pathologic outcomes data were recorded and analyzed.

Results and limitations

A total of 21 LESS-PN were performed (operative time: 111 ± 41 min; blood loss: 196 ± 195 ml: tumor size: 2.0 ± 0.3 cm). Neither conversion to open surgery nor transfusions occurred. Three patients required conversion to standard laparoscopy. Postoperatively, three complications (Clavien grades 2, 3a, and 4) were recorded. Pathologic examination revealed 14 clear cell carcinomas, four renal cysts, two oncocytomas, and one angiomyolipoma. Hospital stay was 4.4 ± 1.9 d. At the last follow-up (mean: 17 ± 11.5 mo), no port-site, local, or distant recurrences were detected. No significant variation in serum creatinine and estimated glomerular filtration rate was observed. Subjective scar evaluation indicated 66% of patients were very satisfied/enthusiastic. Study limitations include the small sample size, the lack of a control group, the short follow-up period, and the arbitrary measure of patient's scar perception.

Conclusions

Unclamped LESS-PN for selected SRMs is a safe and feasible procedure providing favorable postoperative outcomes and ensuring high levels of subjective, cosmetic satisfaction.     

Robotic Partial Nephrectomy with Superselective Versus Main Artery Clamping: A Retrospective Comparison

Background

Concerns have been raised regarding partial nephrectomy (PN) techniques that do not occlude the main renal artery.

Objective

Compare the perioperative outcomes of superselective versus main renal artery control during robotic PN.

Design, setting, and participants

A retrospective analysis of 121 consecutive patients undergoing robotic PN using superselective control (group 1, n = 58) or main artery clamping (group 2, n = 63).

Intervention

Group 1 underwent tumor-specific devascularization, maintaining ongoing arterial perfusion to the renal remnant at all times. Group 2 underwent main renal artery clamping, creating global renal ischemia.

Outcome measurements and statistical analysis

Perioperative and functional data were evaluated. The Pearson chi-square or Fisher exact and Wilcoxon rank sum tests were used.

Results and limitations

All robotic procedures were successful, all surgical margins were negative, and no kidneys were lost. Compared with group 2 tumors, group 1 tumors were larger (3.4 vs 2.6 cm, p = 0.004), more commonly hilar (24% vs 6%, p = 0.009), and more complex (PADUA 10 vs 8, p = 0.009). Group 1 patients had longer median operative time (p < 0.001) and transfusion rates (24% vs 6%, p < 0.01) but similar estimated blood loss (200 vs 150 ml), perioperative complications (15% vs 13%), and hospital stay. Group 1 patients had less decrease in estimated glomerular filtration rate at discharge (0% vs 11%, p = 0.01) and at last follow-up (11% vs 17%, p = 0.03). On computed tomography volumetrics, group 1 patients trended toward greater parenchymal preservation (95% vs 90%, p = 0.07) despite larger tumor size and volume (19 vs 8 ml, p = 0.002). Main limitations are the retrospective study design, small cohort, and short follow-up.

Conclusions

Robotic PN with superselective vascular control enables tumor excision without any global renal ischemia. Blood loss, complications, and positive margin rates were low and similar to main artery clamping. In this initial developmental phase, limitations included more perioperative transfusions and longer operative time. The advantage of superselective clamping for better renal function preservation requires validation by prospective randomized studies.

Patient summary

Preserving global blood flow to the kidney during robotic partial nephrectomy (PN) does not lead to a higher complication rate and may lead to better postoperative renal function compared with clamped PN techniques.     

Renal Pelvic Anatomy Is Associated with Incidence,Grade, and Need for Intervention for Urine Leak Following Partial Nephrectomy

Background

Although the effect of tumor complexity on perioperative outcome measures is well established, the impact of renal pelvic anatomy on perioperative outcomes remains poorly defined.

Objective

To evaluate renal pelvic anatomy as an independent predictor of urine leak in moderate- and high-complexity tumors undergoing nephron-sparing surgery.

Design, setting, and participants

Patients undergoing open partial nephrectomy (PN) for localized RCC were stratified into intermediate- and high-complexity groups using a nephrometry score (7–9 and 10–12, respectively). A renal pelvic score (RPS) was defined by the percentage of renal pelvis contained inside the volume of the renal parenchyma. On this basis, patients were categorized as having an intraparenchymal (>50%) or extraparenchymal (<50%) renal pelvis.

Outcome measurements and statistical analysis

Characteristics of patients with and without an intraparenchymal renal pelvic anatomy were compared.

Results and limitations

Inclusion criteria were met by 255 patients undergoing PN for intermediate (73.6%) and complex (26.4%) localized renal tumors (mean size: 4.6 ± 2.9 cm). Twenty-four (9.6%) renal pelves were classified as completely intraparenchymal. Following stratification by RPS, groups differed with respect to Charlson comorbidity index, body mass index, and largest tumor size, while no differences were observed between hospital length of stay, nephrometry score, estimated blood loss, operative time, and age. Intrarenal pelvic anatomy was associated with a markedly increased risk of urine leak (75% vs 6.5%; p = 0.001), secondary intervention (37.5% vs 3.9%; p < 0.001), and prolonged duration of urine leak (93 ± 62 d vs 56 ± 29 d; p = 0.025).

Conclusions

Intraparenchymal renal pelvic anatomy is an uncommon anatomic variant associated with an increased rate of urine leak following PN. Elevated pressures within a small intraparenchymal renal pelvis might explain the increased risk. Preoperative imaging characteristics suggestive of increased risk for urine leak should be considered in perioperative management algorithms.     

Impact of the Learning Curve on Perioperative Outcomes in Patients Who Underwent Robotic Partial Nephrectomy for Parenchymal Renal Tumours

Background

Robot-assisted partial nephrectomy (RAPN) is an emerging, minimally invasive technique to treat patients with small renal masses.

Objective

To evaluate the impact of the learning curve on perioperative outcomes such as operative times and warm ischaemia times (WIT), blood loss, overall complications, and renal function impairment in patients who underwent RAPN.

Design, setting, and participants

We collected prospectively the clinical and pathologic records of 62 consecutive patients who underwent RAPN between September 2006 and November 2009 for renal tumours at a nonacademic teaching institution by a single surgeon with extensive prior robotic experience.

Interventions

The surgeon used transperitoneal RAPN with excision of an adequate rim of healthy peritumour renal parenchyma.

Measurements

Perioperative parameters, pathologic outcome, and short-term outcomes for renal function were recorded. The effects of the learning curve on the previous reported perioperative and functional outcomes was studied.

Results and limitations

The mean pathologic tumour size was 2.8 ± 1.3 cm. A pelvicaliceal repair was needed in 33 cases (53%). The mean console time was 91 ± 33 min (range: 52–180), with a mean WIT of 20 ± 7 min (range: 9–40). Warm ischaemia (<20 min) and console times were optimised after the first 30 (p < 0.001) and 20 cases (p < 0.001), respectively. Pathologic results yielded a positive surgical margin (PSM) rate of 2%. Mean creatinine level changed from a baseline value of 1.02 ± 0.38 mg/dl to 1.1 ± 0.7 mg/dl 3 mo after surgery. Estimated glomerular filtration rate changed from a baseline value of 81.17 ± 29 to 80.5 ± 29 (millilitres per minute per 1.73 m²) 3 mo postoperatively.

Conclusions

RAPN is a viable option for nephron-sparing surgery in patients with renal carcinoma. Specifically, in the hands of a surgeon with extensive robotic experience, RAPN requires a short learning curve to reach WIT <20 min, console times <100 min, limited blood loss, and acceptable overall complication rates.     

Overall Survival and Development of Stage IV Chronic Kidney Disease in Patients Undergoing Partial and Radical Nephrectomy for Benign Renal Tumors

Background

Although partial nephrectomy (PN) has been associated with improved renal function compared with radical nephrectomy (RN) for renal cell carcinoma, the impact on overall survival (OS) remains controversial.

Objective

To evaluate comparative OS and renal function in patients following PN and RN for a renal mass where malignancy was not a confounding factor.

Design, setting, and participants

Using the Mayo Clinic Nephrectomy Registry, we retrospectively identified 442 patients with unilateral sporadic benign renal masses treated surgically with PN or RN between 1980 and 2008.

Outcome measurements and statistical analysis

The primary outcome measures were OS and the incidence of new-onset stage IV chronic kidney disease (CKD), determined using the Kaplan-Meier method. Cox models were used to test the association of nephrectomy type with these outcomes.

Results and limitations

Overall, 206 and 236 patients with benign renal masses were surgically treated with RN and PN, respectively. Patients who underwent RN were older (median age: 67 vs 64 yr; p = 0.02) and had larger tumors (median size: 5.0 vs 2.7 cm; p < 0.001). Median follow-up for patients still alive at last follow-up was 8.3 yr (range: 0.1–27.9 yr). Estimated OS (95% confidence interval [CI]) rates at 10 and 15 yr were 69% (62–76%) and 53% (45–62%) for RN compared with 80% (73–87%) and 74% (65–83%) following PN (p = 0.032). After adjusting for covariates of interest, patients treated with RN were significantly more likely to die from any cause (hazard ratio [HR]: 1.75; 95% CI, 1.08–2.83; p = 0.023) or develop stage IV CKD (HR: 4.23; 95% CI, 1.80–9.93; p < 0.001) compared with patients who underwent PN. Limitations include the retrospective design, selection bias for surgical approach, and referral bias to a tertiary care facility.

Conclusions

Our data suggest that PN may confer a clinical benefit for improved renal function and better OS compared with RN after excluding the confounding effect of malignancy.     

Assessment of Risk Factors for Complications of Laparoscopic Partial Nephrectomy

Objective

Laparoscopic partial nephrectomy (LPN) is a technique that is emerging as an attractive option for the treatment of renal tumors ≤4 cm. We retrospectively analyzed our experience with LPN to identify patient and tumor features that correlate with a higher risk of complications.

Material and methods

From January 2001 to May 2007, 90 patients underwent LPN at our institution for a clinically localized renal tumor. A retrospective chart review was carried out. Clinical and pathological information were collected for each patient, including patient age and body mass index, tumor size, location and pattern of growth (cortical vs. corticomedullar), surgical approach (transperitoneal vs. retroperitoneal), warm ischemia time, technique that was used to achieve hemostasis, maximum thickness of the margin of resection, and histology. Statistical analysis (chi-square test, Fisher exact test, Mann-Whitney U test, linear regression model) was performed to test the correlation between the above-mentioned variables and the occurrence of complications.

Results

Twenty-two patients (24.4%) had surgical and/or medical complications in our series. The only variable that was found to significantly correlate with a higher number of complications was a corticomedullar tumor growth pattern as opposed to a cortical growth pattern (p = 0.02).

Conclusions

LPN is an attractive alternative to open partial nephrectomy for the treatment of small renal tumors. On the basis of our experience, the selection of patients with cortical renal lesions seems to be required to reduce the risk of complications and therefore maximize the advantages of this minimally invasive but challenging procedure.     

Relapse of unilateral favorable histology Wilms’ tumor: Significant clinicopathological factors

Purpose

To evaluate the clinicopathological features that indicate relapse and suggest a new risk based therapeutic strategy for unilateral Favorable Histology Wilms Tumor (FH-WT).

Materials & Methods

Thirty-three patients with unilateral WT were treated in two institutions between 1986 and 2010. Twenty-eight patients with FH-WT received primary nephrectomy according to the National Wilms’ Tumor Study (NWTS) or the Japanese Wilms’ Tumor Study (JWiTS) protocol. Retrospective analyses of the non-relapsed group (n = 23) and the relapsed group (n = 5) compared age, gender, tumor laterality, tumor weight, initial tumor stage, known histological subtype, chemotherapy (2 or 3 drugs), and any irradiation delivered. Stages and histological subtypes of the tumors were re-evaluated according to the Japanese staging system.

Results

Five of the twenty-eight tumors relapsed, and one patient died. The initial staging (P = 0.029) and the histological subtype (P = 0.003) were the only factors indicating relapse. Nine of the twenty-three tumors were histologically classified as blastemal predominant subtype (BPT-WT). Five relapsed.

Conclusion

According to the basic Japanese therapeutic strategy, all patients underwent a primary nephrectomy before chemotherapy. This study suggests that the histological subtype pre-treatment “BPT-WT” should be included as a strong indicator of poor prognosis. Such patients should be treated as a high-risk group.     

Multi-institutional analysis of robotic partial nephrectomy for hilar versus nonhilar lesions in 446 consecutive cases

Background

Minimally invasive approaches to partial nephrectomy have been rapidly gaining popularity but require advanced laparoscopic surgical skills. Renal hilar tumors, due to their anatomic location, pose additional technical challenges to the operating surgeon.

Objective

We compared the outcomes of robot-assisted partial nephrectomy (RPN) for hilar and nonhilar tumors in our large multicenter contemporary series of patients.

Design, setting, and participants

We retrospectively reviewed prospectively collected data on 446 consecutive patients who underwent RPN by renal surgeons experienced in minimally invasive techniques at four academic institutions from June 2006 to March 2010. Patients were stratified into two groups: those with hilar lesions and those with nonhilar lesions.

Measurements

Patient demographics, operative outcomes, and postoperative outcomes, including oncologic outcomes, were recorded.

Results and limitations

Forty-one patients (9%) had hilar renal masses; 405 patients (91%) had nonhilar masses. There was no statistical differences in patient demographics except for larger median tumor size in the hilar cohort (3.2 cm vs 2.6 cm; p = 0.001). The only significant difference in operative outcomes was an increase in warm ischemia times for the hilar group versus the nonhilar group (26.3 ± 7.4 min vs 19.6 ± 10.0 min; p = <0.0001). There were no differences in postoperative outcomes; however, there was a trend for increased risk of malignancy and higher stage tumors in the hilar lesion group. Final pathologic margin status was similar in both groups. Only one patient in the nonhilar group had evidence of recurrence at 21 mo. The study was limited by the lack of standard anatomic classification of renal tumors and the potential influence of the surgeons’ prior robotic experience.

Conclusions

The data represent the largest series of its kind and strongly suggest that RPN is a safe, effective, and feasible option for the minimally invasive approach to renal hilar tumors with no increased risk of adverse outcomes compared with nonhilar tumors in the hands of experienced robotic surgeons.     

Illness Uncertainty and Quality of Life of Patients with Small Renal Tumors Undergoing Watchful Waiting: A 2-year Prospective Study

Background

Few studies have examined factors associated with the quality of life (QOL) of patients with renal tumors. Illness uncertainty may influence QOL.

Objective

To prospectively examine the influence of uncertainty on general and cancer-specific QOL and distress in patients undergoing watchful waiting (WW) for a renal mass.

Design, setting, and participants

In 2006–2010, 264 patients were enrolled in a prospective WW registry. The decision for WW was based on patient, tumor, and renal function characteristics at the discretion of the urologist and medical oncologist in the context of the physician–patient interaction. Participants had suspected clinical stage T1–T2 disease, were aged ≥18 yr, and spoke and read English. The first 100 patients enrolled in the registry participated in this study.

Outcome measurements and statistical analysis

Patients completed questionnaires on demographics, illness uncertainty (Mishel Uncertainty in Illness Scale), general QOL (Medical Outcomes Study 36-item short-form survey), cancer-specific QOL (Cancer Rehabilitation Evaluation System–Short Form), and distress (Impact of Events Scale) at enrollment and at 6, 12, and 24 mo. Age, gender, ethnicity, tumor size, estimated glomerular filtration rate, comorbidities, and assessment time point were controlled for in the models.

Results and limitations

Among the sample, 27 patients had biopsies, and 17 patients had proven renal cell carcinoma. Growth rate was an average of 0.17 cm/yr (standard deviation: 0.35). Mean age was 72.5 yr, 55% of the patients were male, and 84% of the patients were Caucasian. Greater illness uncertainty was associated with poorer general QOL scores in the physical domain (p = 0.008); worse cancer-related QOL in physical (p = 0.001), psychosocial (p < 0.001), and medical (p = 0.034) domains; and higher distress (p < 0.001).

Conclusions

This study is among the first to prospectively examine the QOL of patients with renal tumors undergoing WW and the psychosocial factors that influence QOL. Illness uncertainty predicted general QOL, cancer-specific QOL, and distress. These factors could be targeted in psychosocial interventions to improve the QOL of patients on WW.     

Single-Port Laparoscopic and Robotic Partial Nephrectomy

Background

Partial nephrectomy (PN) for small renal masses provides effective oncologic outcomes. Single-port laparoscopic (SPL) and robotic surgeries are evolving approaches to advance minimally invasive surgery.

Objective

To determine the feasibility of laparoscopic and robotic single-port PN.

Design, setting, and participants

Since 2007, evaluation of patients undergoing SPL and single-port robotic (SPR) PN at a primary referral center was performed. Patients with small, solitary, exophytic-enhancing renal masses were selected. Patients with a solitary kidney, endophytic or hilar tumors, and previous abdominal and/or kidney surgery were excluded. Perioperative and pathologic data were entered prospectively into an institutional review board (IRB)–approved database.

Interventions

Tumor location determined either an open Hasson transperitoneal or retroperitoneal approach. A single multichannel port or Triport provided intra-abdominal access. The Harmonic Scalpel was used for tumor excision under normal renal perfusion. The da Vinci surgical robot was used for SPR cases.

Measurements

Patient demographics, perioperative, hematologic, and pathologic data as well as pain assessment using the Visual Analog Pain Scale (VAPS) were assessed.

Results and limitations

A total of seven patients underwent single-port PN (SPL = 5, SPR = 2). One patient with a right anterior upper-pole mass required conversion from SPL to standard laparoscopy following tumor excision because of intraoperative bleeding. Pathology revealed six lesions compatible with renal cell carcinoma (RCC) and one benign cyst. One negative frozen section came back focally positive on final histopathology. All other surgical margins were negative. A mean difference of 3.0 ± 2.0 g/dl in hemoglobin was noted in all patients. Minimal pain was noted at discharge following both laparoscopic and robotic single-port surgery (VAPS = 1.7 ± 1.2 vs 1 ± 0.5/10).

Conclusions

SPL and SPR PN is feasible for select exophytic tumors. Robotics may improve surgical capabilities during single-port surgery.