Nephron Sparing Surgery for Renal Cell Carcinoma With Normal Contralateral Kidney: 25 Years of Experience

Oncological and functional outcomes of patients who underwent open partial nephrectomy for kidney tumor

OBJECTIVE

To report long-term functional and oncological outcomes of OPN Methods: We enrolled 182 patients who underwent consecutive OPN with a diagnosis of kidney tumor in our clinic between April 2002 and February 2020 and were selected from our prospective OPN database. Preoperative demographic and clinical characteristics, intraoperative and pathological results, and patients' postoperative functional and oncological follow-up data were retrospectively analyzed. Overall survival (OS) and disease- free survival (DFS) were evaluated using Kaplan-Meier survival analysis. The time-dependent variation between preoperative and postoperative functional results was statistically analyzed and presented in a graph.

RESULTS AND LIMITATIONS

The mean age was 54.4 ± 10.8 yr, and the median age-adjusted Charlson comorbidity index (ACCI) was 1 (interquartile range [IQR] 0-1). The mean tumor size was 3.1 ± 1.2 cm, and the median RENAL score was 6 (IQR 5-8). The most common malign histopathological subtype was clear cell carcinoma with 76.6%, and five cases (3.4%) had positive surgical margins (PSMs). The most common surgical techniques were the retroperitoneal approach (98.9%) and cold ischemia (88.5%). Estimated glomerular filtration rate (eGFR) preservation was 92% (80.8-99.3, IQR), which translates to 32% chronic kidney disease (CKD) upstaging. Acute kidney injury (AKI) was detected in 27 (14.8%) patients according to RIFLE criteria. The intraoperative complication rate was 5.5%, and the postoperative overall complication rate (Clavien-Dindo 1-5) was 30.2%. Major complications (Clavien-Dindo 3-5) were observed in 13 (7.1%) patients. The median oncological follow-up was 42 mo (21.3- 84.6, IQR), and the 5- and 10-yr OS were 90.1% and 78.6%, 5 and 10-yr DFS were 99.4% and 92.1%, respectively. No local recurrence was observed in 5 (3.4%) patients with PSMs; only one had distant metastasis in the 8th postoperative month. The retrospective design, the small number of patients who underwent PN based on mandatory indication, and one type of surgical approach may limit the generalizability of our findings.

CONCLUSIONS

This study confirms excellent long-term oncologic and functional outcomes after OPN in a cohort of patients selected from a single institution. In light of the information provided by the literature and our study, our recommendation is to push the limits of PN under every technically feasible condition in the treatment of kidney tumors to protect the kidney reserve and achieve near-perfect oncological results.

"Could Patient Age and Gender, along with Mass Size, Be Predictive Factors for Benign Kidney Tumors?": A Retrospective Analysis of 307 Consecutive Single Renal Masses Treated with Partial or Radical Nephrectomy

Due to the increased use of common and non-invasive abdominal imaging techniques over the last few decades, the diagnosis of about 60% of renal tumors is incidental. Contrast-enhancing renal nodules on computed tomography are diagnosed as malignant tumors, which are often removed surgically without first performing a biopsy. Most kidney nodules are renal cell carcinoma (RCC) after surgical treatment, but a non-negligible rate of these nodules may be benign on final pathology; as a result, patients undergo unnecessary surgery with an associated significant morbidity. Our study aimed to identify a subgroup of patients with higher odds of harboring benign tumors, who would hence benefit from further diagnostic examinations (such as renal biopsy) or active surveillance. We performed a retrospective review of the medical data, including pathology results, of patients undergoing surgery for solid renal masses that were suspected to be RCCs (for a total sample of 307 patients). Owing to the widespread use of common and non-invasive imaging techniques, the incidental diagnosis of kidney tumors has become increasingly common. Considering that a non-negligible rate of these tumors is found to be benign after surgery at pathological examination, it is crucial to identify features that can correctly diagnose a mass as benign or not. According to our study results, female sex and tumor size ≤ 3 cm were independent predictors of benign disease. Contrary to that demonstrated by other authors, increasing patient age was also positively linked to a greater risk of malign pathology.

Evaluation of the safety of retroperitoneal laparoscopic partial nephrectomy by investigating the perioperative indicators

Background

In recent years, open nephron sparing partial nephrectomy (OPN) has been gradually applied and generally accepted. Recent statistical data show that PN not only can safely and effectively preserve the functional nephron, but also has fewer complications, low local recurrence rate and no significant difference in long-term survival rate compared with nephrectomy/radical nephrectomy, which has gradually become a routine treatment for small renal cell carcinoma. Therefore, how to maximize the protection of postoperative residual renal function (RRF) and reduce the risk of CKD while achieving the ideal local and overall tumor control effect is the key to the treatment of renal cancer, and is also the focus of attention of urologists and nephrologists.

Objective

To evaluate the safety of retroperitoneal laparoscopic partial nephrectomy (RLPN) by investigating the perioperative indicators and postoperative follow-up.

Methods

A total of 40 hospitalized patients in our hospital from December 2019 to December 2021 were selected and followed up for a long time. Patients with renal tumors less than 4cm in diameter and exogeneous or partial exogeneity were randomly divided into 2 groups. Patients in retroperitoneal laparoscopic group (n = 20) were treated with nephron sparing partial nephrectomy (0.5-1cm). Twenty patients underwent retroperitoneal laparoscopic radical nephrectomy (LRN).The time of removal of drainage tube, drainage volume, time of feeding activity and postoperative hospital stay were recorded, and the safety of the operation was evaluated.

Results

nephron sparing partial nephrectomy is suitable for patients with localized renal carcinoma or benign tumor <4cm. RLPN can be applied to all indications of open nephron sparing partial nephrectomy (OPN), with good safety, and can preserve residual renal function to the greatest extent. The operative vascular occlusion time was controlled within 40 minutes, and the use of renal function protection measures during the operation was safe and controllable in reducing the prevention of warm ischemic kidney damage, with good safety. The renal tumor capsule with 0.5cm~1cm margin was complete by postoperative pathology. In the process of tumor resection and suture collection system in the RLPN group, we improved the previous operation of "resection before hemostasis" to "resection while hemostasis" and "knot-free suture" technology, which saved the operation time of intracavity suture knotting. Reduced cortical tear caused by vertical pull during knot tying. The combined effect of biological clip and hemostatic gauze can stimulate the granulation proliferation of renal cortical wound and accelerate the repair. With the combination of knot-free suture and renal segment vascular occlusion, hot ischemic kidney damage is reduced. In the RLPN group, there were no complications of urinary fistula and bleeding, and no abnormal changes in renal function during follow-up. The safety of RLPN group is worthy of affirmation.

Conclusion

The perioperative safety and short-term postoperative renal function recovery of RLPN are good, and the overall safety of this operation is worthy of affirmation.

"To Be or Not to Be Benign" at Partial Nephrectomy for Presumed RCC Renal Masses: Single-Center Experience with 195 Consecutive Patients

In daily medical practice, an increasing number of kidney masses are being incidentally detected using common imaging techniques, owing to the improved diagnostic accuracy and increasingly frequent use of these techniques. As a consequence, the rate of detection of smaller lesions is increasing considerably. According to certain studies, following surgical treatment, up to 27% of small enhancing renal masses are identified as benign tumors at the final pathological examination. This high rate of benign tumors challenges the appropriateness of surgery for all suspicious lesions, given the morbidity associated with such an intervention. The objective of the present study was, therefore, to determine the incidence of benign tumors at partial nephrectomy (PN) for a solitary renal mass. To meet this end, a total of 195 patients who each underwent one PN for a solitary renal lesion with the intent to cure RCC were included in the final retrospective analysis. A benign neoplasm was identified in 30 of these patients. The age of the patients ranged from 29.9-79 years (average: 60.9 years). The tumor size range was 1.5-7 cm (average: 3 cm). All the operations were successful using the laparoscopic approach. The pathological results were renal oncocytoma in 26 cases, angiomyolipomas in two cases, and cysts in the remaining two cases. In conclusion, we have shown in our present series the incidence rate of benign tumors in patients who have been subjected to laparoscopic PN due to a suspected solitary renal mass. Based on these results, we advise that the patient should be counseled not only about the intra- and post-operative risks of nephron-sparing surgery but also about its dual therapeutic and diagnostic role. Therefore, the patients should be informed of the considerably high probability of a benign histological result.

A case of perirenal non-specific lymphadenitis mimicking a solitary renal mass

INTRODUCTION

Since the diagnosis of small renal masses is often a challenge despite improvements in imaging modalities, renal tumor biopsy provides useful information regarding treatment decisions. However, there is no established treatment strategy when renal biopsy shows lymphoid tissue.

CASE PRESENTATION

A 63-year-old woman was referred to our department for the investigation of a small renal mass. Contrast-enhanced computed tomography showed a weakly enhancing mass 39 × 17 mm in diameter in the left kidney. A renal tumor biopsy was performed, and histopathological examination showed lymphoid tissue, but the diagnosis was not confirmed. The tumor was bluntly dissected from the renal capsule via robotic-assisted laparoscopic surgery without renal artery clamping. The pathological diagnosis was non-specific lymphadenitis.

CONCLUSION

We report a rare case of perirenal non-specific lymphadenitis mimicking a solitary renal mass. Non-specific lymphadenitis is a possible differential diagnosis of renal masses.

Imaging and surgical predictive factors for postoperative hemorrhage after partial nephrectomy and clinical results of trans-arterial embolization

ABSTRACT

Partial nephrectomy (PN) has been established as the standard treatment for T1 renal tumors, and postoperative hemorrhage due to vascular complications is a rare but potentially life-threatening complication reported after PN. Thus, this study evaluated the imaging and surgical factors associated with postoperative hemorrhage after PN and the clinical results of trans-arterial embolization. A retrospective review of the institutional PN database was performed from May 2012 to January 2019, revealing that we performed 810 PN procedures at our institution. In total, 12 patients were referred to the interventional radiology department for vascular complications after the procedure. Patients with and without transarterial embolization (TAE) were age- and sex-matched with 56 patients. Preoperative imaging characteristics and operative details were considered. Univariable and multivariable analyses were used to test their eventual association with the occurrence of hemorrhage. Furthermore, renal functions at diagnosis, after operation or embolization for TAE cases, and at the last follow-up were recorded. A diagnosis of hemorrhage was made at a median of 4 (range, 0-25) days after surgery. The majority of patients (50%) presented with gross hematuria. T test revealed higher renal tumor-parenchyma contact area (TPA) (P = .0407), Length-A (P = .0136), Length-P (P = .0267), operation time (P = .0214) and estimated blood loss (P = .0043) in patients with hemorrhage than in controls. Binary logistic regression analysis identified TPA (P = .048) and estimated blood loss (P = .042) as independent predictors for postoperative hemorrhage with an area under the ROC curve of 0.705 (64% sensitivity and 79% specificity). In conclusion, the occurrence of hemorrhage after PN was associated with a larger TPA and more estimated blood loss during the procedure. In patients who underwent selective TAE, renal function remained comparable with that of controls.

Natural History of Asymptomatic Pseudoaneurysm Soon After Robot-assisted Partial Nephrectomy: Single-center Prospective Study

OBJECTIVE

To prospectively investigate the natural history of asymptomatic pseudoaneurysm after robotic-assisted partial nephrectomy.

METHODS

Robotic-assisted partial nephrectomy was undertaken for 67 patients between July 2014 and July 2018. Patients who could not undergo enhanced CT were excluded, so 60 patients were finally included in the present study. We prospectively investigated the presence of pseudoaneurysm based on early enhanced CT scan on postoperative day 7. According to our treatment policy, patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Meanwhile, patients with asymptomatic pseudoaneurysm were observed with follow-up CT imaging, regardless of the size of the aneurysm.

RESULTS

Overall incidence of pseudoaneurysm on postoperative day 7 was 18% (11/60 cases). The median size of the pseudoaneurysm was 9 mm (quartile: 6-12 mm). Two patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Nine patients had asymptomatic pseudoaneurysm; in 8 of these it disappeared without therapeutic intervention. The median period from surgery to confirmed disappearance of the aneurysm was 19 days (quartile 14-32 days). In the remaining 1 patient, small asymptomatic pseudoaneurysm (2 mm) could still be observed even 1 year after surgery.

CONCLUSION

Our study showed high incidence of pseudoaneurysm 1 week after robotic-assisted partial nephrectomy that mostly disappeared without therapeutic intervention. Routine enhanced CT screening and pre-emptive embolization may not be necessary for asymptomatic renal artery pseudoaneurysm.

The Complete Spectrum of Infiltrative Renal Masses: Clinical Characteristics and Prognostic Implications

OBJECTIVE

To analyze the full spectrum of patients presenting with radiologically-identified infiltrative renal masses (IRMs), including those managed surgically or otherwise, with focus on clinical presentation/prognosis.

METHODS

All 280 patients presenting with radiologically-identified renal mass with infiltrative features (2008-2017) were retrospectively reviewed. Poorly-defined interface between tumor and parenchyma and irregular shape (nonelliptical) in one or more distinct/unequivocal areas were required for classification as IRM. IRM was confirmed in 265 and clinical characteristics and outcomes were assessed.

RESULTS

Median age/tumor size were 65-years/6.9 cm, respectively, and 225 patients (85%) were R.E.N.A.L. = 10-12. Overall, 181 patients (68%) presented symptomatically, locally-advanced cancer (cT3-T4) was observed in 176 (66%) and disseminated disease and/or lymphadenopathy (>2 cm) in 181(68%). Clinical/radiographic findings were suggestive of etiology and could direct evaluation, but were nonspecific for definitive diagnosis. Renal-mass biopsy was performed in 103 patients and diagnostic in 97 (94%). Renal surgery was only performed in 82 patients (31%) and partial nephrectomy in 3 (1.1%). Overall, 72 patients (27%) received systemic chemotherapy and 59 (22%) targeted therapy. Final-diagnosis was renal cell carcinoma in 94 patients (35%), including 49 with highly-aggressive histology (sarcomatoid/rhabdoid/collecting-duct/medullary/unclassified). High-grade urothelial-carcinoma was found in 70 (26%), and lymphoma/metastatic cancer in 26 (10%)/25 (9%), respectively. Overall, 153 patients (58%) died; 138 (52%) cancer-related at median of 5 months. The majority of patients with renal cell carcinoma, urothelial-carcinoma, and renal metastasis died, almost exclusively cancer-related, at medians of 8, 3, and 2 months, respectively.

CONCLUSION

Our series includes the full spectrum of IRMs and confirms predominance of symptomatic, poorly-differentiated, highly-lethal malignancies. Our study highlights the overriding importance of identifying infiltrative features, a simple radiologic diagnosis, during assessment of renal masses.

Personalized Treatment for Small Renal Tumors: Decision Analysis of Competing Causes of Mortality

Purpose To compare the effectiveness of personalized treatment for small (≤4 cm) renal tumors versus routine partial nephrectomy (PN), accounting for various competing causes of mortality. Materials and Methods A state-transition microsimulation model was constructed to compare life expectancy of management strategies for small renal tumors by using 1 000 000 simulations in the following ways: routine PN or personalized treatment involving percutaneous ablation for risk factors for worsening chronic kidney disease (CKD), and otherwise PN; biopsy, with triage of renal cell carcinoma (RCC) to PN or ablation depending on risk factors for worsening CKD; active surveillance for growth; and active surveillance when MRI findings are indicative of papillary RCC. Transition probabilities were incorporated from the literature. Effects of parameter variability were assessed in sensitivity analysis. Results In patients of all ages with normal renal function, routine PN yielded the longest life expectancy (eg, 0.67 years in 65-year-old men with nephrometry score [NS] of 4). Otherwise, personalized strategies extended life expectancy versus routine PN: in CKD stages 2 or 3a, moderate or high NS, and no comorbidities, MRI guidance for active surveillance extended life expectancy (eg, 2.60 years for MRI vs PN in CKD 3a, NS 10); and with Charlson comorbidity index of 1 or more, biopsy or active surveillance for growth extended life expectancy (eg, 2.70 years for surveillance for growth in CKD 3a, NS 10). CKD 3b was most effectively managed by using MRI to help predict papillary RCC for surveillance. Conclusion For patients with chronic kidney disease and small renal tumors, personalized treatment selection likely extends life expectancy. © RSNA, 2019 Online supplemental material is available for this article.

Organ-sparing procedures in GU cancer: part 1-organ-sparing procedures in renal and adrenal tumors: a systematic review

PURPOSE

Organ-sparing surgery (OSS) for the kidney and adrenals has emerged as the need for preservation of function is paramount in patients with poor functional reserve. As reports increasingly showed that oncological outcomes were equivalent to radical excision, elective OSS became a viable alternative in patients with otherwise normal reserve. In this review, we summarize the current knowledge of OSS for adrenal and renal tumors.

MATERIALS AND METHODS

PubMed, Web of Science and Cochrane Library Central Search were searched for recently published articles up to December 2017. The following keywords were used; "partial adrenalectomy", "adrenal sparing", "partial nephrectomy", "nephron sparing", "kidney/renal cancer".

RESULTS

Partial adrenalectomy became an attractive alternative to total adrenalectomy avoiding adrenal insufficiency. Both minimally invasive surgery and ablative techniques were increasingly reported for adrenal OSS with adequate residual adrenal function and excellent oncological outcome. Radical nephrectomy remained for many years as the gold standard of treatment for organ-confined renal cell carcinoma. As the need to reduce the impact on renal function, more conservative approaches were utilized. Soon, the non-inferiority of nephron-sparing surgery to that of radical excision became evident and elective partial nephrectomy was gaining ground as the standard of care for small renal masses in patients with normal contralateral kidneys.

CONCLUSIONS

Herein, we present a comprehensive review of the current status of OSS in renal and adrenal tumors.

Influence of symptomatic pseudoaneurysms on postoperative renal function after partial nephrectomy: results of a matched pair analysis

PURPOSE

A symptomatic pseudoaneurysm (SPA) is a rare but severe complication after partial nephrectomy (PN). Selective trans-arterial embolization (TAE) is the treatment of choice with high success rates. However, the influence of this intervention on postsurgical renal function has not been studied.

METHODS

Between 2005 and 2016 we performed 1047 PNs at our institution. Postsurgical SPA occurred in 40 patients (3.8%). Patients with and without SPA were matched in a 1:2 ratio concerning tumor complexity (RENAL) and pre-operative renal function (CKD stage). Any CKD upstage and a relevant CKD progression (CKD ≥ III) were defined as endpoints. Furthermore, the influence of the amount of contrast agent applied during TAE was assessed.

RESULTS

All patients with SPA were treated successfully with TAE. No significant difference could be detected concerning clinical, functional and surgical aspects. Median follow-up time accounted for 12.5 (6.75-27.5) months. Kaplan-Meier analyses detected an increased rate of any CKD upstage (p = 0.066) and relevant CKD progression (p = 0.01) in patients with SPA. Multivariate analysis identified post-operative SPA to be an independent predictor for a relevant CKD progression (HR 4.15, p = 0.01). The amount of contrast agents used did not have an impact on the development of a relevant CKD progression (p = 0.72).

CONCLUSION

Patients treated with TAE after PN show an additional risk for an impairment of renal function over time. Hence, those patients should explicitly be informed about possible consequences and closely monitored by nephrologists.

Positive surgical margins are predictors of local recurrence in conservative kidney surgery for pT1 tumors

OBJECTIVES

The clinical significance of positive surgical margin (PSM) after a Nephron Sparing Surgery (NSS) is controversial. The aim of this study is to evaluate the association between PSM and the risk of disease recurrence in patients with pT1 kidney tumors who underwent NSS.

MATERIALS AND METHODS

Retrospective cohort study. A total of 314 patients submitted to a NSS due to stage pT1 renal tumor between January 2010 and June 2015 were included. Recurrence-free survival was estimated. The Cox model was used to adjust the tumor size, histological grade, pathological stage, age, surgical margins and type of approach.

RESULTS

Overall PSM was 6.3% (n=22). Recurrence was evidenced in 9.1% (n=2) of patients with PSM and 3.5% (n=10) for the group of negative surgical margin (NSM). The estimated local recurrence-free survival rate at 3 years was 96.4% (95% CI 91.9 to 100) for the NSM group and 87.8% (95% CI 71.9 to 100) for PSM group (p=0.02) with no difference in metastasis-free survival. The PSM and pathological high grade (Fuhrman grade III or IV) were independent predictors of local recurrence in the multivariate analysis (HR 12.9, 95%CI 1.8-94, p=0.011 / HR 38.3, 95%CI 3.1-467, p=0.004 respectively). Fuhrman grade proved to be predictor of distant recurrence (HR 8.1, 95%CI 1.6-39.7, p=0.011).

CONCLUSIONS

The PSM in pT1 renal tumors showed to have higher risk of local recurrence and thus, worse oncological prognosis.

Does the Renal Parenchyma Adjacent to the Tumor Contribute to Kidney Function? A Critical Analysis of Glomerular Viability in Partial Nephrectomy Specimens

OBJECTIVE

To evaluate the viability of glomeruli in the peritumor parenchyma of partial nephrectomy specimens removed for renal cell carcinoma (RCC) and relate it to kidney function, to better understand the contribution of peritumor parenchyma to renal function.

MATERIALS AND METHODS

A retrospective analysis of 53 partial nephrectomies containing RCC was performed. Glomeruli within 0.25-cm increments from the tumor were quantified and histologically assessed for viability. Tumor size, minimum and maximum margin size, and pre- and postoperative estimated glomerular filtration rate (eGFR) were obtained.

RESULTS

Glomerular viability positively correlated with distance from tumor with mean viable glomeruli in successive 0.25-cm increments of 0-0.25 cm, 58%; 0.25-0.5 cm, 80%; 0.5-0.75 cm, 90%; and 0.75-1.0 cm, 92%. Glomerular viability near the tumor did not correlate with preoperative eGFR, whereas decreased viability further from the tumor did correlate with worse preoperative eGFR. Tumor size showed a nonstatistically significant positive trend with minimum (median 0.15 cm) and maximum margin (median 0.7 cm) sizes. Percent change of glomerular filtration rate did not correlate with margin size (P = .190).

CONCLUSION

Renal parenchyma immediately adjacent to RCC contains fewer viable glomeruli compared with the parenchyma further from the tumor. Based on this information, attempts to preserve all non-neoplastic renal parenchyma via a surgical margin approaching zero may not necessarily result in clinically relevant differences in the amount of viable glomeruli remaining or the renal function preserved.

Microsimulation model of CT versus MRI surveillance of Bosniak IIF renal cystic lesions: should effects of radiation exposure affect selection of imaging strategy?

OBJECTIVE

The objective of this study was to quantify the effects of radiation-induced cancer risks in patients with Bosniak category IIF lesions undergoing CT versus MRI surveillance.

MATERIALS AND METHODS

We developed a Markov-Monte Carlo model to determine life expectancy losses attributable to radiation-induced cancers in hypothetical patients undergoing CT versus MRI surveillance of Bosniak IIF lesions. Our model tracked hypothetical patients as they underwent imaging surveillance for up to 5 years, accounting for potential lesion progression and treatment. Estimates of radiation-induced cancer mortality were generated using a published organ-specific radiation-risk model based on Biological Effects of Ionizing Radiation VII methods. The model also incorporated surgical mortality and renal cancer-specific mortality. Our primary outcome was life expectancy loss attributable to radiation-induced cancers. A sensitivity analysis was performed to assess the stability of the results with variability in key parameters.

RESULTS

The mean number of examinations per patient was 6.3. In the base case, assuming 13 mSv per multiphase CT examination, 64-year-old men experienced an average life expectancy decrease of 5.5 days attributable to radiation-induced cancers from CT; 64-year-old women experienced a corresponding life expectancy loss of 6.9 days. The results were most sensitive to patient age: Life expectancy loss attributable to radiation-induced cancers increased to 21.6 days in 20-year-old women and 20.0 days in 20-year-old men. Varied assumptions of each modality's (CT vs MRI) depiction of lesion complexity also impacted life expectancy losses.

CONCLUSION

Microsimulation modeling shows that radiation-induced cancer risks from CT surveillance for Bosniak IIF lesions minimally affect life expectancy. However, as progressively younger patients are considered, increasing radiation risks merit stronger consideration of MRI surveillance.

Laparoscopic and open partial nephrectomy: a UK centre's experience

Introduction

Laparoscopy allows minimally invasive approaches for procedures traditionally performed openly, with associated lower morbidity. Nephron-sparing surgery (NSS) is mostly regarded as an open procedure because laparoscopic partial nephrectomy (LPN) is technically challenging. We evaluated our centre's experience with LPN and open partial nephrectomy (OPN).

Methods

All patients over five years (2005–2010) undergoing NSS were identified retrospectively from our operating room management information system. Case notes, diagnostic and post-operative surveillance imaging were reviewed. Post-operative morbidity, histopathology and serum full blood count and urea and electrolyte reports were recorded.

Results

A total of 97 OPNs and 23 LPNs were performed. Median length of stay was six days for OPNs and three days for LPNs (p= 0.005). Mean drop in haemoglobin (Hb) was 2.6 g/dl for both OPNs and LPNs. No significant difference in transfusion rates was observed. Median warm ischaemia time (WIT) for OPNs was 14 minutes and 32 minutes for LPNs (p < 0.0001). No significant difference was seen in changes from baseline serum creatinine when comparing OPNs with LPNs at day 1 (p = 0.7572) and at 12 months (p = 0.7406) post-operatively. Surgical margins were positive in 20 (21.5%) OPNs and negative in all LPNs (p = 0.038). One patient developed local recurrence following OPN (clear margins) and two patients developed distant metastases.

Conclusions

Benefits of LPN include shorter hospital stay and satisfactory long-term preservation of renal function, despite longer WITs. This demonstrates the benefits of LPNs in patients with single exophytic renal tumours performed by highly experienced, regionally selected laparoscopists.

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

OBJECTIVE

To describe the contemporary patterns of care for renal cell carcinoma (RCC) using a whole of population series from Victoria.

PATIENTS AND METHODS

Retrospective review of medical records of all patients diagnosed and treated for RCC in Victoria in 2009. Patients were identified via the State-wide Victorian Cancer Registry. Patient demographic characteristics, symptoms, stage, and first-line treatment were assessed. Associations between case residential location (metropolitan or rural) and treatment were examined using multivariate logistic regression after adjusting for age, sex, socioeconomic status, treatment in private or public hospital and comorbidity.

RESULTS

Data were obtained for 499 of 577 eligible patients. In all, 413 patients (83%) underwent surgery. Laparoscopic radical nephrectomy (RN) was the most common procedure for Stage I pT1a/pT1b tumours (51.2%); partial nephrectomy (PN) was performed for 27% of Stage I RCC In multivariate analysis, regional patients were less likely to receive PN (odds ratio [OR] 0.39, 95% confidence interval [CI] 0.18-0.85) for Stage I RCC, and less likely to receive systemic therapy for Stage IV RCC (OR 0.06, 95% CI 0.01-0.41). Multidisciplinary team meetings were recorded for only 25% of patients and 3% were enrolled in a clinical trial.

CONCLUSION

Most contemporary patients diagnosed with RCC are still treated with RN, including those with smaller tumours amenable to PN. This may impact future outcomes, including increased risk of chronic kidney disease and its potential financial healthcare burden. Patterns of treatment also appear to differ between metropolitan and regional populations.

Comparison between laparoscopic and open partial nephrectomy: surgical, oncologic, and functional outcomes

The surgical, oncologic, and functional outcomes were retrospectively compared of laparoscopic partial nephrectomy (LPN) and open partial nephrectomy (OPN) for the treatment of renal masses. Between January 2006 and November 2011, 115 LPNs and 97 OPNs were performed. The patients' demographics were matched. Their intraoperative and postoperative data, oncologic and renal function outcomes were compared. Surgical time, renal arterial occlusion time, estimated blood loss, and postoperative hospitalization days were shorter in the LPN group (p < 0.01). The total complications were comparable; however, LPN had a higher intraoperative complication due to 12 subcutaneous emphysemas. The LPN group was followed up with a mean time of 29.3 ± 14.4 months and the OPN group with a mean time of 31.2 ± 12.6 months. All patients survived and no distant relapse or metastasis were observed. Kaplan-Meier estimates of 60-month local recurrence-free survival were comparable with 92.4% after LPN and 93.8% after OPN, respectively (p = 0.57). The reduction of glomerular filtration rate was more obvious after LPN at the 3-month follow-up (p < 0.01), but similar between the two groups at the 30.2-month follow-up. LPN provides similar results in oncologic and functional outcomes when compared to OPN. Long-term observations are still required to the oncologic and function outcomes.

Diffusion-weighted imaging of focal renal lesions: a meta-analysis

OBJECTIVES

Contrast-enhanced MRI can only distinguish to a limited extent between malignant and benign focal renal lesions. The aim of this meta-analysis is to review renal diffusion-weighted imaging (DWI) to compare apparent diffusion coefficient (ADC) values for different renal lesions that can be applied in clinical practice.

METHODS

A PubMed search was performed to identify relevant articles published 2004-2011 on renal DWI of focal renal lesions. ADC values were extracted by lesion type to determine whether benign or malignant. The data table was finalised in a consensus read. ADC values were evaluated statistically using meta-regression based on a linear mixed model. Two-sided P value <5 % indicated statistical significance.

RESULTS

The meta-analysis is based on 17 studies with 764 patients. Renal cell carcinomas have significant lower ADC values than benign tissue (1.61 ± 0.08 × 10(-3) mm(2)/s vs 2.10 ± 0.09 × 10(-3) mm(2)/s; P < 0.0001). Uroepithelial malignancies can be differentiated by lowest ADC values (1.30 ± 0.11 × 10(-3) mm(2)/s). There is a significant difference between ADC values of renal cell carcinomas and oncocytomas (1.61 ± 0.08 × 10(-3) mm(2)/s vs 2.00 ± 0.08 × 10(-3) mm(2)/s; P < 0.0001).

CONCLUSIONS

Evaluation of ADC values can help to determine between benign and malignant lesions in general but also seems able to differentiate oncocytomas from malignant tumours, hence potentially reducing the number of unnecessarily performed nephrectomies.

KEY POINTS

• This meta-analysis assesses the role of diffusion-weighted MRI in renal lesions. • ADC values obtained by DW MRI have been compared for different renal lesions. • ADC values can help distinguish between benign and malignant tumours. • Differentiating oncocytomas from malignant tumours can potentially reduce inappropriate nephrectomies.

Predictors of postoperative renal functional damage after nephron-sparing surgery

BACKGROUND

Although nephron-sparing surgery has been reported not to affect total renal function, it is a non-negligible fact that functional damage of the operated kidney usually results, for various reasons. This study aimed to explore the effects of preoperative baseline characteristics, tumor characteristics, and function protection methods on postoperative renal damage.

METHODS

This study was a retrospective review of 51 patients who underwent open nephron-sparing surgery. The mean age of the patients (39 men, 12 women) was 54.2 ± 13.9 years, range 32 to 71 years. The glomerular filtration rate (GFR) was measured preoperatively and 6th months after the operation. Univariate analysis was used to screen indicators with significant differences in different levels of renal function damage. All variables found to be significant on univariate analysis were entered into a multiple logistic regression model to predict risk factors for renal function damage.

RESULTS

Univariate analysis showed that there was a significant difference in age, GFR of operated kidney, tumor diameter, tumor depth, and ischemic protection type between patients with little damage and those with heavy damage (P < 0.05). Forward stepwise logistic regression analysis suggested that age (odds ratio, 3.08; 95% confidence interval 1.78 to 7.04; P = 0.037), preoperative GFR of operated kidney (odds ratio, 0.51; 95% confidence interval 0.11 to 0.73; P = 0.033), and tumor diameter (odds ratio, 5.49; 95% confidence interval 2.14 to 7.88; P = 0.012) and depth (odds ratio, 5.82; 95% confidence interval 2.66 to 8.06; P = 0.010) were independent risk factors for postoperative renal function damage.

CONCLUSIONS

Patients with older age, poor renal function, and large tumor diameter and depth might be at higher risk of renal function damage after nephron-sparing surgery.

Evaluation of renal masses with contrast-enhanced ultrasound

The clinical need for characterising small renal masses (SRMs) is increasing due to their rising incidental detection. This increase is especially seen in younger and older generations and concerns mainly SRMs. Diagnostics is mainly made by contrast-enhanced CT or MRI. However, these imaging methods fail to accurately distinguishing benign from malignant SRMs. Other disadvantages of CT or MRI are high costs, the use of ionizing radiation, nephrotoxicity induced by iodine contrast agents or nephrogenic systemic fibrosis (NSF) induced by gadolinium contrast agents. Contrast-enhanced ultrasound (CEUS) is based on ultrasonography and microbubbles to real-time visualize the renal blood flow without the use of nephrotoxic agents or ionizing radiation. This comprehensive review evaluates the capabilities of CEUS in the diagnostics of benign (angiomyolipomas, cysts, oncocytomas, pseudotumors) and malignant masses (renal cell carcinomas), and focuses on possible future treatment.

Tumour location as a predictor of benign disease in the management of renal masses

OBJECTIVE

To investigate the association between tumour location and the proportion of benign disease in renal masses presumed to be renal cell carcinoma (RCC) preoperatively.

METHODS

This Institutional Review Board approved study includes 196 patients who underwent surgical treatment for renal masses <5 cm at our institution by a single surgeon between January 2002 and June 2009. Based on preoperative imaging, each mass was designated as central (touching or encroaching upon the renal collecting system and/or renal sinus) or peripheral. The association between tumour location and benign pathology was determined using univariate and multiple logistic regression, including tumour size and patient sex in the model.

RESULTS

The proportion of histologically confirmed benign disease in this series was 11.2%. The proportion of benign disease by location was 5.9% and 19.5% for central and peripheral masses, respectively. The effect of location was found to have a significant prognostic value (p = 0.0273) with an adjusted odds ratio of 3.51 (95% CI = 1.38-19.62) for the odds of a benign diagnosis in peripheral compared to central tumours. Tumour size and patient sex were not significant predictors of benign pathology (p = 0.483 and 0.191, respectively).

CONCLUSIONS

Peripherally located renal masses are more likely to be benign than centrally located renal masses. This information may be used when selecting strategies for the management of renal masses presumed to be RCC.

[Renal function in the elderly after radical tumor nephrectomy and partial nephrectomy]

Due to rising life-expectancy and increasing use of tomography more elderly patients with incidental renal tumors are being diagnosed. The current article gives an overview of kidney function after renal surgery in the elderly and the aim is to give assistance in clinical practice for deciding how to adequately treat these patients.

Comparison of renal function after partial nephrectomy and radical nephrectomy for renal cell carcinoma

OBJECTIVE

To investigate the time-dependent changes of estimated glomerular filtration rate (eGFR) after radical nephrectomy (RN) and partial nephrectomy (PN) for renal cell carcinoma (RCC) and to determine the risk factors for the new onset of a postoperative eGFR <60 ml/min/1.73 m(2).

PATIENTS AND METHODS

We assessed the renal function of 253 RCC patients by using the eGFR, and investigated the time-dependent changes of the eGFR after the operation. Regression models were used to determine risk factors for the new onset of an eGFR of <60 ml/min/1.73 m(2) in 211 patients who had at least one month of postoperative follow-up.

RESULTS

From the first postoperative day to the 60th postoperative month the eGFR in the RN group was significantly lower than that in the PN group. For patients who had at least 1 month of postoperative follow-up, multivariable analysis revealed that RN (p < 0.001), age (p = 0.028), and maleness (p = 0.013) were risk factors for the postoperative onset of an eGFR <60 ml/min/1.73 m(2).

CONCLUSIONS

Renal function after PN was better than that after RN, and RN was a greater risk factor for the postoperative onset of an eGFR <60 ml/min/ 1.73 m(2).

Prevalence and predictors of benign lesions in renal masses smaller than 7 cm presumed to be renal cell carcinoma

The present study was designed to determine the incidence and predictive factors of benign renal lesions in 450 patients who underwent surgical removal of solitary renal masses <7 cm in diameter. Of the 450 renal masses, 88 (19.9%) were benign lesions. Female sex, nephron-sparing surgery, surgery between 1990 and 1996, cystic components on imaging, and small tumors (<4 cm) were independently associated with benign pathology.

PURPOSE

To determine the association between preoperative parameters with final benign pathology in patients who underwent surgical removal of solitary renal masses <7 cm in diameter.

MATERIALS AND METHODS

A database of 450 patients without metastatic disease who underwent radical nephrectomy or nephron-sparing surgery (NSS) for removal of renal masses <7 cm between January 1990 and December 2009 was reviewed. Age, sex, symptoms, year and type of surgery, solid or cystic appearance, and tumor size were analyzed as presumed predictors of benign pathology. Multivariate analysis was performed to identify parameters associated with benign pathology.

RESULTS

In all, 88 (19.9%) of the tumors were benign, including 39 (8.7%) oncocytomas and 22 (4.9%) angiomyolipomas. The benign lesion rate for tumors ≤2, 2.1-4, and 4.1-7 cm was 30.3%, 27.1%, and 12.5%, respectively (2P < .001). For the periods of 1990-1996, 1997-2003, and 2004-2009, the frequency of benign tumors was 25%, 17.3%, and 18.4% (2P = .271), the incidental tumor rate was 48.1%, 60.4%, and 63.8% (2P = .027), mean tumor size was 5, 4.6, and 4.1 cm (2P < .001), and the NSS rate was 28.8%, 43.2%, and 52.7% (2P < .001), respectively. Logistic regression analysis revealed that female sex, NSS, surgery between 1990 and 1996, cystic components on imaging, and small tumors (<4 cm) based on radiologic examination were independently associated with benign pathology (odds ratio [OR] = 3.26, 2.56, 2.43, 2.41, and 1.96, respectively).

CONCLUSIONS

The incidence of incidental and small tumors amenable to NSS increased over time. Female sex was the strongest predictor of benign pathology.

Open nephron-sparing surgery in renal tumors with normal contralateral kidney: A single centre experience of 8 years

Introduction:

We present our eight-year experience with open nephron-sparing surgery (NSS) in renal tumors with contralateral normal kidney to assess its oncological efficacy and safety.

Materials and Methods:

Thirty-six patients undergoing open NSS for small localized renal tumors with normal contralateral kidney from January 1998 to August 2006 were studied regarding demographic, clinical and pathological characteristics along with long-term follow-up.

Results:

The mean age was 48.28 ± 9.5 years. The mean tumor size was 3.72 cm (range 1.5-6). The following surgeries were performed: Wedge resection-13, partial polar nephrectomy-15, segmental resection-eight. The following techniques were used for vascular control: clamping and cooling-eight, warm ischemia-12, a novel technique of serial encirclage-16. The mean warm ischemia time was 23.2 ± 3.2 min. The mean operating time was 190.07 ± 11.3 min. The mean estimated blood loss was 331 ± 17.4 ml. The majority of renal tumors were renal cell carcinoma (97.22%). There were no positive surgical margins. There were no major intraoperative and postoperative complications. The mean follow up was 52.1 months (range 4-80) with no case showing progression to renal insufficiency (defined as serum creatinine > 2 mg/dl). There was only one local recurrence. However, four distant metastases were reported. The five-year cancer-specific survival, recurrence-free survival and overall survival were 94.4%, 88.88% and 86.11% respectively.

Conclusions:

In patients with solitary, small localized, unilateral renal tumors with normal contralateral kidney, elective open NSS is feasible, safe and provides excellent long-term local control and oncological efficacy with functional benefits.

Open versus robot-assisted partial nephrectomy: effect on clinical outcome

BACKGROUND AND PURPOSE

Robot-assisted partial nephrectomy (RPN) has emerged as a viable alternative to open partial nephrectomy (OPN) for small renal masses (SRMs). Comparative outcomes of RPN and OPN at a single institution were analyzed.

PATIENTS AND METHODS

A retrospective review was performed to compare 69 RPNs with 234 OPNs between May 2003 and December 2010 at a single institution. Clinicopathologic variables, operative parameters, and renal functional outcomes were analyzed.

RESULTS

There were no significant differences between the two cohorts (RPN vs OPN) with respect to patient age (P=0.609), sex (P=0.703), preoperative estimated glomerular filtration rate (eGFR, P=0.146), estimated blood loss (P=0.600), and tumor size (P=0.256). The mean operative time was longer in the RPN group (192 vs 142 min, P<0.001). The mean warm ischemia time was longer in the RPN cohort (22.99 vs 18.87 min, P<0.001), but there were no significant differences in the postoperative eGFR (P=0.162) and change in the eGFR (P=0.520). The length of hospitalization (6.2 vs 8.9 d, P<0.001) and use of postoperative analgesics (ketoprofen, 0.26 vs 0.88 ampules, P<0.001) were more favorable in the RPN cohort. The number of patients with positive surgical margins was 0 for the RPN and 6 for the OPN groups. The intraoperative complication rates were 4.35% and 4.27% in the RPN and OPN groups, respectively (P=0.999). The overall postoperative complication rates were 8.7% and 15.4% in the RPN and OPN groups, respectively (P=0.158).

CONCLUSIONS

RPN is a viable option as a nephron-sparing surgical procedure for SRMs considering the perioperative parameters and postoperative renal function changes, in addition to the traditional benefits of the laparoscopic procedure.

Value of T2-weighted MR imaging in differentiating low-fat renal angiomyolipomas from other renal tumors

BACKGROUND

Accurate preoperative diagnosis of fat scanty angiomyolipomas is an important clinical issue. By evaluating the low signal intensity of angiomyolipomas in MR T2-weighted images the diagnostic accuracy can be elevated.

PURPOSE

To retrospectively assess the usefulness of T2-weighted MR imaging for differentiating low-fat angiomyolipomas (AMLs) from other renal tumors.

MATERIAL AND METHODS

We retrospectively evaluated 71 patients with surgically proven renal masses (10 AMLs, 57 renal cell carcinomas [RCCs], and four oncocytomas), all of which showed no visible fat as well as gradual enhancement patterns on contrast-enhanced CT. Signal intensity was measured in each renal mass and in the spleen on T2-weighted images, and each signal intensity ratio (SIR) was calculated; SIR values were then compared in the AML and non-AML groups. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of the two parameters for differentiating the two groups.

RESULTS

The SIR values (77 ± 24% vs. 162 ± 79%, p = 0.002) were significantly lower in the AML than in the non-AML group. The area under the ROC curve was 0.926 for SIR. The sensitivity and specificity in the diagnosis of AMLs were 90% and 90.2%, using SIR cut-off of 92.5%.

CONCLUSION

Signal intensity measurements on T2-weighted MR images can differentiate AML from non-AML in the kidney.

[Partial nephrectomy for cancer and percutaneous biopsy: Oncologic results]

OBJECTIVES

To evaluate the results of partial nephrectomy (NP) for cancer in 60 patients selected by the biopsy of the tumor by analyzing the information, oncologic follow-up.

PATIENTS

It was a cohort study unicenter retrospective from 1994 to 2006. The biopsy was systematically done for patients who were candidates for elective NP. The criteria for elective indications NP tumors were less than 4cm, low grade Fuhrman (I and II). The tubulopapillary tumors (TBP) on biopsy were excluded from the elective indications. The parameters studied were the biopsy data, overall survival, disease-free survival.

RESULTS

The median age was 59 years (32-79 years) and 69% of tumor were fortuitous discovery. Indications of need accounted for 30% of cases (single kidney, bilateral tumors and chronic renal failure [CRF]). Biopsy allowed a diagnosis in 89% of cases. There was one death in specific postoperative immediately. A final histology was 75% of clear cell carcinoma, 13.3% of chromophobe and 11.7% of TBP, 96.6% of T1a including 86.6% of low grade and no surgical margin. The median follow-up was 49 months with 98.5% of specific survival at 5 years, one local recurrence and no general recurrence.

CONCLUSION

The study has shown that the selection of patients by biopsy gives satisfactory carcinologic results with 98.5% specific survival at the end of follow-up; it is between 89 and 100% in the literature.

Incidence and predictive factors of benign renal lesions in Korean patients with preoperative imaging diagnoses of renal cell carcinoma

The present study was performed to determine the incidence and predictive factors of benign renal lesions in Korean patients undergoing nephrectomy for presumed renal cell carcinoma on preoperative imaging. We analyzed the pathologic reports and medical records of 1,598 eligible patients with unilateral, nonmetastatic, and nonfamilial renal masses. Of the 1,598 renal masses, 114 (7.1%) were benign lesions, including angiomyolipoma in 47 (2.9%), oncocytoma in 23 (1.4%), and complicated cysts in 18 (1.1%) patients. On univariate analysis, the proportion of benign lesions was significantly higher in female patients, and in patients with smaller tumors, cystic renal masses, and without gross hematuria as a presenting symptom. When renal lesions were stratified by tumor size, the proportion of benign as opposed to malignant lesions decreased significantly as tumor size increased. On multivariate analysis, female gender, smaller tumor size, and cystic lesions were significantly associated with benign histological features. The findings in this large cohort of Korean patients show a lower incidence (7.1%) of benign renal lesions than those of previous Western reports. Female gender, cystic renal lesions, and smaller tumor size are independent predictors of benign histological features.

Renal mass biopsy to guide treatment decisions for small incidental renal tumors: a cost-effectiveness analysis

PURPOSE

To evaluate the effectiveness, cost, and cost-effectiveness of using renal mass biopsy to guide treatment decisions for small incidentally detected renal tumors.

MATERIALS AND METHODS

A decision-analytic Markov model was developed to estimate life expectancy and lifetime costs for patients with small (< or = 4-cm) renal tumors. Two strategies were compared: renal mass biopsy to triage patients to surgery or imaging surveillance and empiric nephron-sparing surgery. The model incorporated biopsy performance, the probability of track seeding with malignant cells, the prevalence and growth of benign and malignant tumors, treatment effectiveness and costs, and patient outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference under a willingness-to-pay threshold of $75,000 per quality-adjusted life-year (QALY). Effects of changes in key parameters on strategy preference were evaluated in sensitivity analysis.

RESULTS

Under base-case assumptions, the biopsy strategy yielded a minimally greater quality-adjusted life expectancy (4 days) than did empiric surgery at a lower lifetime cost ($3466), dominating surgery from a cost-effectiveness perspective. Over the majority of parameter ranges tested in one-way sensitivity analysis, the biopsy strategy dominated surgery or was cost-effective relative to surgery based on a $75,000-per-QALY willingness-to-pay threshold. In two-way sensitivity analysis, surgery yielded greater life expectancy when the prevalence of malignancy and propensity for biopsy-negative cancers to metastasize were both higher than expected or when the sensitivity and specificity of biopsy were both lower than expected.

CONCLUSION

The use of biopsy to guide treatment decisions for small incidentally detected renal tumors is cost-effective and can prevent unnecessary surgery in many cases.