Partial nephrectomy: alternative treatment for selected patients with renal cell carcinoma

Selective Trans-arterial Embolization of Iatrogenic Vascular Lesions Did Not Influence the Global Renal Function After Partial Nephrectomy

OBJECTIVE

To evaluate the renal function outcomes after selective trans-arterial embolization (SAE) of iatrogenic vascular lesions (IVL), including pseudoaneurysm and arteriovenous fistula, following partial nephrectomy (PN).

MATERIALS AND METHODS

A multi-institutional study was conducted including consecutive patients who underwent PN between January 2009 and March 2019. Two surgical approaches were used: open and robot-assisted PN. Patients with SAE were identified and matched (1:2) with patients without IVL. The matching criteria were age, gender, Charlson score, creatinine clearance, RENAL score, and tumor size. The primary outcome was the evolution of global renal function at 6-months postoperatively.

RESULTS

A total of 493 consecutive PN (360 open PN and 133 robot-assisted PN) were included. IVL occurred in 17 cases (3.4%) without statistical difference according to the surgical approach (P = .78). Patients from embolization group were matched to 34 cases without postoperative IVL. Groups were comparable concerning clinical, tumor and surgical characteristics. The clinical success of SAE, defined as the absence of recourse to a second embolization or a total nephrectomy, was obtained in 16 (94.1%) cases. No minor or major complications were reported after SAE. The preoperative estimated glomerular filtration rate (eGFR) was similar between control group (93 [85-102] ml/min) and embolization group (95 [83-102] ml/min) (P = .99). Median (IQR) eGFR between control group (87 [72-95] ml/min) and embolization group (83 [76-93] ml/min) at a follow-up of 6 months showed no significant difference (P = .73).

CONCLUSION

IVL are rare complications of PN. SAE is an effective and minimally invasive management tool, with no deleterious effect on global renal function.

Dual Laplacian regularized matrix completion for microRNA-disease associations prediction

Since lots of miRNA-disease associations have been verified, it is meaningful to discover more miRNA-disease associations for serving disease diagnosis and prevention of human complex diseases. However, it is not practical to identify potential associations using traditional biological experimental methods since the process is expensive and time consuming. Therefore, it is necessary to develop efficient computational methods to accomplish this task. In this work, we introduced a matrix completion model with dual Laplacian regularization (DLRMC) to infer unknown miRNA-disease associations in heterogeneous omics data. Specifically, DLRMC transformed the task of miRNA-disease association prediction into a matrix completion problem, in which the potential missing entries of the miRNA-disease association matrix were calculated, the missing association can be obtained based on the prediction scores after the completion procedure. Meanwhile, the miRNA functional similarity and the disease semantic similarity were fully exploited to serve the miRNA-disease association matrix completion by using a dual Laplacian regularization term. In the experiments, we conducted global and local Leave-One-Out Cross Validation (LOOCV) and case studies to evaluate the efficacy of DLRMC on the Human miRNA-disease associations dataset obtained from the HMDDv2.0 database. As a result, the AUCs of DLRMC is 0.9174 and 0.8289 in global LOOCV and local LOOCV, respectively, which significantly outperform a variety of previous methods. In addition, in the case studies on four significant diseases related to human health including Colon Neoplasms, Kidney neoplasms, Lymphoma and Prostate neoplasms, 90%, 92%, 92% and 94% out of the top 50 predicted miRNAs has been confirmed, respectively.

TLHNMDA: Triple Layer Heterogeneous Network Based Inference for MiRNA-Disease Association Prediction

In recent years, microRNAs (miRNAs) have been confirmed to be involved in many important biological processes and associated with various kinds of human complex diseases. Therefore, predicting potential associations between miRNAs and diseases with the huge number of verified heterogeneous biological datasets will provide a new perspective for disease therapy. In this article, we developed a novel computational model of Triple Layer Heterogeneous Network based inference for MiRNA-Disease Association prediction (TLHNMDA) by using the experimentally verified miRNA-disease associations, miRNA-long noncoding RNA (lncRNA) interactions, miRNA function similarity information, disease semantic similarity information and Gaussian interaction profile kernel similarity for lncRNAs into an triple layer heterogeneous network to predict new miRNA-disease associations. As a result, the AUCs of TLHNMDA are 0.8795 and 0.8795 ± 0.0010 based on leave-one-out cross validation (LOOCV) and 5-fold cross validation, respectively. Furthermore, TLHNMDA was implemented on three complex human diseases to evaluate predictive ability. As a result, 84% (kidney neoplasms), 78% (lymphoma) and 76% (prostate neoplasms) of top 50 predicted miRNAs for the three complex diseases can be verified by biological experiments. In addition, based on the HMDD v1.0 database, 98% of top 50 potential esophageal neoplasms-associated miRNAs were confirmed by experimental reports. It is expected that TLHNMDA could be a useful model to predict potential miRNA-disease associations with high prediction accuracy and stability.

MCMDA: Matrix completion for MiRNA-disease association prediction

Nowadays, researchers have realized that microRNAs (miRNAs) are playing a significant role in many important biological processes and they are closely connected with various complex human diseases. However, since there are too many possible miRNA-disease associations to analyze, it remains difficult to predict the potential miRNAs related to human diseases without a systematic and effective method. In this study, we developed a Matrix Completion for MiRNA-Disease Association prediction model (MCMDA) based on the known miRNA-disease associations in HMDD database. MCMDA model utilized the matrix completion algorithm to update the adjacency matrix of known miRNA-disease associations and furthermore predict the potential associations. To evaluate the performance of MCMDA, we performed leave-one-out cross validation (LOOCV) and 5-fold cross validation to compare MCMDA with three previous classical computational models (RLSMDA, HDMP, and WBSMDA). As a result, MCMDA achieved AUCs of 0.8749 in global LOOCV, 0.7718 in local LOOCV and average AUC of 0.8767+/−0.0011 in 5-fold cross validation. Moreover, the prediction results associated with colon neoplasms, kidney neoplasms, lymphoma and prostate neoplasms were verified. As a consequence, 84%, 86%, 78% and 90% of the top 50 potential miRNAs for these four diseases were respectively confirmed by recent experimental discoveries. Therefore, MCMDA model is superior to the previous models in that it improves the prediction performance although it only depends on the known miRNA-disease associations.

Partial nephrectomy versus radical nephrectomy for clinical localised renal masses

BACKGROUND

Partial nephrectomy and radical nephrectomy are the relevant surgical therapy options for localised renal cell carcinoma. However, debate regarding the effects of these surgical approaches continues and it is important to identify and summarise high-quality studies to make surgical treatment recommendations.

OBJECTIVES

To assess the effects of partial nephrectomy compared with radical nephrectomy for clinically localised renal cell carcinoma.

SEARCH METHODS

We searched CENTRAL, MEDLINE, PubMed, Embase, Web of Science, BIOSIS, LILACS, Scopus, two trial registries and abstracts from three major conferences to 24 February 2017, together with reference lists; and contacted selected experts in the field.

SELECTION CRITERIA

We included a randomised controlled trial comparing partial and radical nephrectomy for participants with small renal masses.

DATA COLLECTION AND ANALYSIS

One review author screened all of the titles and abstracts; only citations that were clearly irrelevant were excluded at this stage. Next, two review authors independently assessed full-text reports, identified relevant studies, evaluated the eligibility of the studies for inclusion, assessed trial quality and extracted data. The update of the literature search was performed by two independent review authors. We used Review Manager 5 for data synthesis and data analyses.

MAIN RESULTS

We identified one randomised controlled trial including 541 participants that compared partial nephrectomy to radical nephrectomy. The median follow-up was 9.3 years.Based on low quality evidence, we found that time-to-death of any cause was decreased using partial nephrectomy (HR 1.50, 95% CI 1.03 to 2.18). This corresponds to 79 more deaths (5 more to 173 more) per 1000. Also based on low quality evidence, we found no difference in serious adverse events (RR 2.04, 95% CI 0.19 to 22.34). Findings are consistent with 4 more surgery-related deaths (3 fewer to 78 more) per 1000.Based on low quality evidence, we found no difference in time-to-recurrence (HR 1.37, 95% CI 0.58 to 3.24). This corresponds to 12 more recurrences (14 fewer to 70 more) per 1000. Due to the nature of reporting, we were unable to analyse overall rates for immediate and long-term adverse events. We found no evidence on haemodialysis or quality of life.Reasons for downgrading related to study limitations (lack of blinding, cross-over), imprecision and indirectness (a substantial proportion of patients were ultimately found not to have a malignant tumour). Based on the finding of a single trial, we were unable to conduct any subgroup or sensitivity analyses.

AUTHORS' CONCLUSIONS

Partial nephrectomy may be associated with a decreased time-to-death of any cause. With regards to surgery-related mortality, cancer-specific survival and time-to-recurrence, partial nephrectomy appears to result in little to no difference.

Pilot study comparing the two hemostatic agents in patients undergoing partial nephrectomy

Background

Recently studies have demonstrated improved outcomes in patients undergoing nephron-sparing surgery (NSS) for low stage renal tumors, thus NSS is widely accepted as the treatment option for these patients. With NSS, there is a risk of renal hemorrhage and thus haemostatic agents may be routinely applied to the cut surface of the kidney. Herein we compare two commercially available haemostatic agents applied intra-operatively to the cut surface of the kidney. Post-operative outcomes (oncologic and non-oncologic) are reported.

Methods

The medical records of 23 patients with suspicious renal mass documented on axial imaging and who underwent open NSS via a mini-subcostal incision were extensively reviewed. One of two haemostatic agents (Floseal^®, n = 11; Arista^®, n = 12) was intra-operatively applied to the cut surface of the kidney. Chi-square and T- student test was used to compare outcomes between the cohort of 11 patients who had Floseal^® and the 12 patients who had Arista^®.

Results

Median pre-operative size of renal mass was 4.3 cm (range 1.5-7.0 cm). Final pathology revealed 3 oncocytomas and 20 renal cell carcinoma (17 clear cell, 1 chromophobe and 2 papillary), pT1a = 14 and pT1b = 6. Mean intra-operative blood loss and hospital stay between the Floseal^®vs. Arista^® cohorts did not significantly differ (227 mL vs. 250 mL, p = 0.68 and 4.4 days vs. 4.5 days, p = 0.76, respectively). Intra-operative and post-operative complications were not different between the two cohorts. No recurrences have been documented with a mean follow-up of 18 months.

Conclusion

Along with meticulous surgical technique, the use of either haemostatic agent (Floseal^® or Arista^®) was not associated with high rate of intra-operative or post-operative haemorrhage. Thus either haemostatic agent may be successfully used during NSS.

[The use of Surgisis® optimizes and simplifies partial nephrectomy for large renal tumors]

BACKGROUND

With lower rates of postoperative renal failure, diabetes and cardiovascular disease, partial nephrectomy achieves longer overall survival and equally long tumor-specific survival. It is thus the current gold standard treatment for renal tumors and now also for those ≥ 4 cm in size. The main complications of nephron-sparing surgery, particularly for large and centrally located tumors, are postoperative parenchymal bleeding and urinary fistulas after opening the urinary collecting system (UCS).

MATERIAL AND METHODS

Between August 2003 and April 2012, 76 partial nephrectomies for tumors ≥ 4 cm in size were performed using porcine small intestinal submucosa (SIS, Surgisis®) to close the capsular, renal and in some cases, UCS defects.

RESULTS

The median tumor size was 5.0 cm (range 4.0-13.0 cm) and the intervention was performed with warm ischemia in 25 cases (32.8 %), with cold perfusion in 16 cases (21.2 %) and without ischemia in 35 cases (46.0 %). A total of 4 patients (5.5 %) developed postoperative urinary fistulas and 4 (5.5 %) required revision surgery because of significant postoperative bleeding. There were no local infections or allergic reactions to the foreign material.

CONCLUSIONS

Surgisis® enables a quick and technically uncomplicated closure of the renal defect after partial nephrectomy for tumors. It has the potential to further minimize postoperative bleeding and urinary fistulas and to facilitate the intervention to the extent that nephron-sparing surgery will gain broader acceptance even in patients with tumors ≥4 cm in size.

Sequential combination treatment (arterial embolization and percutaneous radiofrequency ablation) of inoperable renal cell carcinoma: single-center pilot study

BACKGROUND

Potential drawbacks of percutaneous radiofrequency ablation (RFA) for renal cell carcinoma (RCC) include local recurrence after RFA due to a limited ablation area, massive hemorrhage induced by kidney puncture, and difficulty in visualizing the tumor at CT-guided puncture.

PURPOSE

To evaluate retrospectively the technical success, effectiveness, and complications elicited in patients with unresectable RCC following single-session sequential combination treatment consisting of renal arterial embolization followed by RFA.

MATERIAL AND METHODS

Ten patients (12 RCCs) who were not candidates for surgery were included in this pilot study. All tumors ranged from 18-66 mm in size (mean 31 ± 3.9 mm), and were percutaneously ablated several hours after embolization of the tumor vessels with iodized oil and gelatin sponges. We evaluated the technical success, effectiveness, effect on renal function, and complications of this treatment. Effectiveness was judged on CT and/or MR images obtained every three months after RFA. The effect on renal function was assessed based on the creatinine level and glomerular filtration rate (GFR) before, one week, and three months after the procedure.

RESULTS

Renal arterial embolization followed by percutaneous RFA was technically successful in all patients. On contrast CT and/or MR images obtained one week and three months after RFA we observed necrosis in the embolized segment of all RCCs. There were no major complications during and after the procedure. All patients reported tolerable pain and a burning sensation during RFA. After the procedure, five patients (50%) experienced back pain, one each manifested fluid collection, subcapsular hematomas, hematuria, or nausea. There were no instances of recurrence during a mean follow-up period of 47 ± 3.8 months. We noted no significant difference in serum creatinine and GFR before and after treatment.

CONCLUSION

Our pilot study suggests that sequential combination treatment by renal arterial embolization followed by percutaneous RFA is feasible in patients with inoperable RCC. The treatment complications were acceptable and excellent effects were obtained.

[Open partial nephrectomy: standard of minimal invasive surgery]

OBJECTIVE

Partial nephrectomy is now recognized as the standard treatment for tumors less than 7cm. The oncological results are comparable to those obtained by total nephrectomy, while preserving kidney function. Our objective was to describe our experience and research factors associated with complications, recurrence and death.

PATIENTS AND METHODS

Partial nephrectomy performed in our center by June 1996 to December 2008 were reviewed retrospectively. Demographic and tumors characteristics, postoperative complications and patient outcomes were identified. Factors associated with complications and survival were investigated by regression tests.

RESULTS

Of the 96 patients enrolled (mean age 61.4 years±12.8), 13 had renal insufficiency (serum creatinine 120 to 212μmol/L). The mean tumor size was 32mm (±13.9) and 57 (79.2%) corresponded to clear cell carcinoma. The overall rate of postoperative complications was 26%, including 8.3% of hemorrhagic complications and 3.1% of urinary complications. None of the analyzed variables were associated with the occurrence of complications. With a mean of 2 years and 9 months follow-up (±28months), eight patients (11.1%) had tumor recurrence. Multifocal tumors as well as postoperative complications were associated with risk of recurrence. Three patients with positive tumor margins were monitored with no evidence of progression (with 71, 42 and 12 months of follow-up).

CONCLUSION

Our single-center retrospective study of partial nephrectomy for renal tumor showed medium-term oncological results similar to those reported in the total nephrectomy with the advantage of nephron preservation. The results of studies by conventional surgery such as that we report should be a benchmark for laparoscopic surgery.

CT-guided percutaneous cryoablation of renal masses in selected patients

PURPOSE

We analysed our experience with computed tomography (CT)-guided percutaneous cryoablation (PCA) in patients who were not surgical candidates or refused surgery for small to medium-sized renal masses.

MATERIALS AND METHODS

Two freezing cycles were applied and separated by a passive warming cycle using 1.7- and 2.4-mm cryoprobes under either general anaesthesia or sedation based on patient positioning and respiratory status. Postoperative monitoring included haematological and biochemistry evaluation and CT scan 24 h after PCA. Follow-up consisted of a multislice CT scan at 1 month and every 3 months in the first year then every 6 months thereafter.

RESULTS

Thirty-seven patients (38 lesions) underwent 40 PCA procedures; 5/37 (13.5%) had a solitary kidney. Median mass size was 35 (range 12-70) mm. No complications occurred during the procedure. Clavien grade ≥2 anaemia occurred in two patients (5.4 %): one patient required 1 U of packed red blood cells; the other required an arterial embolisation. Serum creatinine did not increase in any case. Two patients showed persisting or recurrent disease at 1 and 9 months, respectively, and both could be re-treated with PCA. All other patients showed a hypodense mass 3 months after PCA, with no contrast enhancement. Subsequent examinations showed that lesion sizes decreased and CT densitometry remained stable or increased minimally, also with no contrast enhancement.

CONCLUSIONS

PCA proved relatively easy and safe and could be considered an effective alternative for patients who are not surgical candidates or refuse surgery, as well as in patients with medium-sized lesions.

Partial nephrectomy using porcine small intestinal submucosa

BACKGROUND

Whenever technically feasible and oncologically justified, nephron-sparing surgery is the current standard of care for localized renal cell carcinomas (RCC). The main complications of partial nephrectomy, especially for large and centrally located tumors, are urinary leakage and parenchymal bleeding. We prospectively evaluated the pros and cons of using porcine small intestinal submucosa (SIS, Surgisis®) to close the renal defect after nephron-sparing surgery.

METHODS

We used Surgisis® (Cook medical, Bloomington, IN, USA) to secure and compress the capsular defect after tumor resection in 123 patients submitted to 129 partial nephrectomies between August 2003 and February 2011.

RESULTS

The median tumor size was 3.7 cm (range 1.1-13.0 cm). Procedures were performed with cold ischemia in 24 cases (18.2%), with warm ischemia in 46 (35.6%), and without ischemia in 59 cases (44.8%). In the total group of patients, 4 (3.1%) developed urinary fistula, and only 2 (1.6%) required postoperative transfusions due to hemorrhage after the application of the small intestinal submucosa membrane.

CONCLUSION

Small intestinal submucosa is an easy-to-use biomaterial for preventing complications such as postoperative bleeding and urinary fistula in nephron-sparing surgery, especially in cases where tumor excision causes significant renal capsular and/or renal pelvic defects.

Image guided percutaneous probe ablation for renal tumors in 65 solitary kidneys: functional and oncological outcomes

PURPOSE

We evaluated the oncological and functional outcomes of computerized tomography guided percutaneous cryotherapy or radio frequency ablation of kidney tumors in patients with a solitary kidney.

MATERIALS AND METHODS

We reviewed the medical charts of patients with a solitary kidney who underwent percutaneous probe ablation for renal masses at our institution from April 2002 through March 2010. Followup consisted of computerized tomography or magnetic resonance imaging 1 day postoperatively, at 3, 6 and 12 months, and annually thereafter. Serum creatinine and estimated glomerular filtration rate were used to measure renal function. The cryotherapy and radio frequency ablation groups were compared for demographics, the 2-year actuarial survival rate and renal function.

RESULTS

Overall 65 patients were included in this retrospective analysis, of whom 29 (44.6%) underwent cryotherapy and 36 (55.4%) underwent radio frequency ablation. Median followup was 15.1 (IQR 4.4 to 32.9) and 38.8 months (13.8 to 50.7), respectively. The 2 groups were comparable in median age, body mass index, American Society of Anesthesiologists score, tumor size and preoperative estimated glomerular filtration rate. The 3 primary treatment failures, including 1 after cryotherapy and 2 after radio frequency ablation, were successfully re-treated with thermal ablation. There were 14 recurrences after radio frequency ablation and 3 after cryotherapy. Two-year actuarial overall, cancer specific, recurrence-free and metastasis-free survival rates for cryotherapy vs radio frequency ablation were 89% vs 93%, 100% vs 96%, 69% vs 58% and 86% vs 91%, respectively. For each group no significant decrease in renal functional parameters was found at the latest followup visit.

CONCLUSIONS

Computerized tomography guided percutaneous probe ablation represents a safe treatment option in surgical patients at high risk with a solitary kidney. It provides low morbidity, acceptable short-term cancer control and minimal clinical impact on postoperative renal function.

A rare type of renal cell carcinoma in a girl: hybrid renal cell carcinoma

Hybrid renal cell carcinoma (HRCN) is a rare type of renal tumor with characteristic pathologic features, including oncocytic and chromophobe cellular content, and shows more favorable prognosis than renal cell carcinoma. The early-stage tumors show favorable outcome, and postoperative regular clinical and radiological follow-up is adequate in most cases. However, close follow-up is mandatory for tumors with histopathologically coexistence of squamous, papillary, and/or eosinophilic RCC component. This report describes a 12-year-old girl with a stage I HRCN who was closely followed after nephrectomy with no further treatment.

Radiofrequency ablation treatment for renal cell carcinoma: early clinical experience

Objective

To evaluate the early clinical experience associated with radiofrequency (RF) ablation in patients with renal cell carcinoma (RCC).

Materials and Methods

The RF ablation treatment was performed on 17 tumors from 16 patients (mean age, 60.5 years; range, 43-73 years) with RCC. The treatment indications were localized, solid renal mass, comorbidities, high operation risk, and refusal to perform surgery. All tumors were treated by a percutaneous CT (n = 10), followed by an US-guided (n = 2), laparoscopy-assisted US (n = 2), and an open (n = 2) RF ablation. Furthermore, patients underwent a follow-up CT at one day, one week, one month, three and six months, and then every six months from the onset of treatment. We evaluated the technical success, technical effectiveness, ablation zone, benign periablation enhancement, irregular peripheral enhancement, and complications.

Results

All 17 exophytic tumors (mean size, 2.2 cm; range, 1.1-5.0 cm) were completely ablated. Technical success and effectiveness was achieved in all cases and the mean follow-up period was 23.8 months (range, 17-33 months). A local recurrence was not detected in any of the cases; however, five patients developed complications as a result of treatment, including hematuria (n = 2), mild thermal injury of the psoas muscle (n = 1), mild hydronephrosis (n = 1), and fistula formation (n = 1).

Conclusion

The RF ablation is an alternative treatment for exophytic RCCs and represents a promising treatment for some patients with small RCCs.

Radiologic evaluation of small renal masses (II): posttreatment management

The increase in the detection of small renal masses (SRMs) and their best knowledge leads to a change in the therapeutic management of these lesions. The use of a less aggressive surgical technique or even an expectant attitude is the current tendency, in order to preserve as much renal function as possible. Imaging techniques are essential in the followup of these lesions. It allows us to know the postsurgical changes and possible complications due to treatment and the presence of local recurrence and metastases. Furthermore, a close radiological followup of SRM related to ablative treatments is mandatory. The purpose of this article is to reveal the imaging features of complications due to surgical or ablative treatments, local recurrence and metastasis, as well as their followup.

Ultrasound guided percutaneous microwave ablation for small renal cancer: initial experience

PURPOSE

We evaluated the feasibility, safety and efficacy of ultrasound guided percutaneous microwave ablation for small renal cell cancers.

MATERIALS AND METHODS

A total of 12 patients with a pathologically proven renal cell cancer 1.3 to 3.8 cm in diameter were treated with microwave ablation. A cooled shaft needle antenna was percutaneously inserted into the tumor under ultrasound guidance. One antenna was used for tumors 2 cm or smaller and antennae were used for tumors larger than 2 cm. One thermocouple was placed about 0.5 cm away from the tumor to monitor temperature in real time during ablation. Microwaves were emitted at 50 W for 500 seconds and prolonged as necessary to attain temperatures sufficient to ensure tumor kill. Immediate treatment efficacy was assessed by contrast enhanced ultrasound 1 day after ablation. Short-term efficacy was assessed by contrast enhanced computerized tomography and/or contrast enhanced ultrasound at 1, 3 and 6 months, and every 6 months thereafter.

RESULTS

All tumors were completely ablated at a single session and no complications occurred. No residual tumor or recurrence was observed at a median followup of 11 months (range 4 to 20). The ablation zone was well defined on contrast enhanced imaging and it gradually shrank with time.

CONCLUSIONS

Ultrasound guided percutaneous microwave ablation appears to be a safe and effective technique for small renal cell cancer in select patients.

Optimized haemostasis in nephron-sparing surgery using small-intestine submucosa

Background

The indications for nephron-sparing surgery are expanding constantly. One major contributing fact for this development is the improvement of haemostatic techniques following excision of the tumor. Nevertheless, postoperative bleeding complications still occur. To prevent this, we prospectively studied the effect of application of small-intestine submucosa (SIS) over the renal defect.

Methods

We performed 55 nephron-sparing surgeries applying SIS between 08/03 and 10/06 in 53 pts. (mean age: 59 yrs., range 29 – 79 yrs.). After resection of the renal tumor and application of a haemostyptic agent, we used SIS to secure and apply compression on the defect.

Results

The final pathology revealed clear-cell and papillary carcinoma, papillary adenoma, oncocytoma, and angiomyolipoma in 39 (70.9%), 6 (10.9), 1 (1.8%), 2 (3.6%) and 7 (12.7%) patients, respectively. The 45 malignant lesions (81.8%) were classified as pT1a and pT1b in 35 (77.8%) and 10 (22.2%) patients, respectively. The median tumor size was 4.5 cm (range: 1.3 – 13 cm). The median operating time was 186 min (range: 90 – 260 min). 18 (32.7%) procedures were performed without ischemia. 23 (41.8%) and 14 (25.5%) cases were operated in in-situ cold and warm ischemia, respectively. The median intraoperative blood loss was 730 cc (range: 100 – 2500 cc). No open operative revision was indicated due to postoperative bleeding complications. Furthermore, there was no necessity to substitute persistent blood loss from the drains postoperatively. No urinoma occurred.

Conclusion

SIS is a highly effective and easy-to-use instrument for preventing postoperative bleeding and urinary fistula complications in nephron-sparing surgery.

Eosinophilic chromophobe renal cell carcinoma in a child with hypospadias

Chromophobe renal cell carcinoma (CRCC) is a distinct variant of renal carcinoma generally affecting adults. We report a case of an unusual CRCC, arising in a male child affected by hypospadias. This case demonstrates that CRCC can occur in the pediatric patients and can be associated with genital tract anomalies such as Wilms tumor.

Open partial nephrectomy in renal cancer: a feasible gold standard technique in all hospitals

Introduction. Partial nephrectomy (PN) is playing an increasingly important role in localized renal cell carcinoma (RCC) as a true alternative to radical nephrectomy. With the greater experience and expertise of surgical teams, it has become an alternative to radical nephrectomy in young patients when the tumor diameter is 4 cm or less in almost all hospitals since cancer-specific survival outcomes are similar to those obtained with radical nephrectomy. Materials and Methods. The authors comment on their own experience and review the literature, reporting current indications and outcomes including complications. The surgical technique of open partial nephrectomy is outlined. Conclusions. Nowadays, open PN is the gold standard technique to treat small renal masses, and all nonablative techniques must pass the test of time to be compared to PN. It is not ethical for patients to undergo radical surgery just because the urologists involved do not have adequate experience with PN. Patients should be involved in the final treatment decision and, when appropriate, referred to specialized centers with experience in open or laparoscopic partial nephrectomies.

[Partial nephrectomy for renal cancers larger than 4 cm]

OBJECTIVE

To compare the results in patients operated by partial nephrectomy (PN) and radical nephrectomy (RN) for renal cancers < 4 cm, between 4 and 7 cm and > 7 cm.

MATERIALS AND METHODS

Retrospective study including 107 patients operated for renal cancer between 1998 and 2004. Demographic characteristics, TNM stage, tumour diameter and type of surgery (PN vs RN) were recorded. The patients' current status was determined and a survival curve was constructed by the Kaplan-Meier method.

RESULTS

35.2% patients were operated by PN and 64.8% were operated by RN. The mean follow-up was 45 months. No significant difference in recurrence-free survival rate was observed between patients operated by PN and RN for tumours < 4 cm (93.3% vs 92.3%, respectively, p = 0.243), or for tumours between 4 and 7 cm (100% vs 89.3%, respectively, p = 0.564) or for tumours > 7 cm (100% vs 85.5%, respectively, p = 0.218).

CONCLUSION

Partial nephrectomy is the standard treatment for tumours < 4 cm, but this study suggests that it is just as effective for tumours up to 7 cm in diameter. Although partial nephrectomy also appears to be a safe treatment for tumours > 7 cm, further studies based on a greater number of tumours in this size category with a longer follow-up are necessary.

Nephron sparing surgery for renal cell carcinoma in a solitary kidney

To determine functional and oncological outcomes of nephron sparing surgery (NSS) for renal cell carcinoma (RCC). We identified from our kidney database 103 consecutive patients undergoing NSS for solid renal tumors in a solitary kidney. After excluding 17 patients (16.5%) undergoing NSS with palliative intent in presence of preoperatively diagnosed metastatic disease (n = 15) or positive lymph nodes (n = 2) and 6 patients (5.8%) who turned out to have benign tumors, the remaining 80 patients with RCC were analyzed. Mean follow-up is 8.0 years (range: 0.1-25.8). Mean tumor size was 4.2 cm (range 1.2-11 cm). Chronic renal failure requiring hemodialysis developed after NSS in nine patients (11.2%). In the remainder, serum creatinine was 1.72 mg/dl (range: 0.45-4.6 mg/dl) at latest follow-up. The cancer specific survival rates at 1, 5 and 10 years were 97.2, 89.6 and 76%, respectively. The estimated local recurrence free survival rates at 1, 5 and 10 years were 97.8, 89.4 and 79.9%, respectively. Univariate analysis of correlation between clinical and pathologic features with death from RCC showed significant associations for grading and tumor size. The long-term data of our series support the concept of organ-sparing surgery for RCC in a solitary kidney since it provides excellent local tumor control and cancer specific survival and preserves renal function renal function so that 89% of patients remained free of dialysis in the long-run.

Oncologic Efficacy of CT-Guided Percutaneous Radiofrequency Ablation of Renal Cell Carcinomas

OBJECTIVE

A single institution's experience with CT-guided percutaneous radiofrequency ablation of biopsy-proven renal cell carcinomas (RCCs) was studied to determine the disease-free survival and complication rate.

MATERIALS AND METHODS

Data from 125 RCCs in 104 patients treated with curative intent was reviewed. Radiofrequency ablation treatments were performed using conscious sedation and local anesthesia. Patients were followed with contrast-enhanced CT or MRI. Tumor control was defined as the absence of contrast enhancement in the tumor on CT or MRI.

RESULTS

Tumor size ranged from 0.6 to 8.8 cm (mean, 2.7 cm; SD, 1.5 cm). Of the 125 treated tumors, 116 (93%) were completely ablated (109 in a single ablation session, seven after a second ablation session) with a mean follow-up interval of 13.8 months. All 95 RCCs smaller than 3.7 cm were completely ablated, and 21 (70%) of 30 larger tumors were completely ablated, with nine showing evidence of residual viable tumor on follow-up scans. Tumor size smaller than 3.7 cm was significantly associated with achieving complete tumor eradication (p < 0.001). With each 1-cm increase in tumor diameter over 3.6 cm, the likelihood of tumor-free survival decreased by a factor of 2.19 (p < 0.001). There were 8 (8%) complications, none of which resulted in long-term morbidity.

CONCLUSION

CT-guided percutaneous radiofrequency ablation is a safe method to treat small RCCs. This study indicates that radiofrequency ablation can reliably eradicate RCCs smaller than 3.7 cm. Treatment of larger RCCs will result in an increased risk of residual RCC.

Effect of radiofrequency ablation of renal tumors on renal function in patients with a solitary kidney

OBJECTIVE

The purpose of this study was to evaluate the effect on renal function of percutaneous radiofrequency ablation of renal tumors in patients with a solitary kidney.

CONCLUSION

Ablation resulted in complete tumor eradication, and there were no serious complications. Percutaneous radiofrequency ablation of renal tumors resulted in a 16% increase in serum creatinine concentration and a 13% decrease in creatinine clearance in patients with one kidney. These results are comparable with those of surgical resection of tumors in this group of patients.

Enucleoresection for the Elective Treatment of Small Renal Cell Carcinoma: Can It Be the Treatment of Choice?

BACKGROUND

We present our findings in a series of T1 renal cell carcinomas (RCC) treated with excision of the tumor surrounded by a minimal layer of grossly normal parenchyma.

PATIENTS AND METHODS

A total of 43 patients who underwent elective nephron-sparing surgery performed with enucleoresection were studied retrospectively. None of the patients had preoperative or intraoperative suspicion of positive nodes and were free from distant metastases before surgery (N0, M0). Patients status was last evaluated in January 2006.

RESULTS

Median age was 58.7 years (35-78). Median tumor size was 3.3 cm (1.5-7). There were no major complications such as bleeding and urinary leakage/ urinoma requiring re-operation. Pathological stage was pT1a in 38 (89%), pT1b in 4 (9%) and pT3a in 1 (2%) patient. Median followup was 32 months (6-89). A total of 5 patients with RCC had died as of January 2006. Overall, 3 (6.9%) patients had disease progression, of whom 2 (4.6%) were local recurrence, 1 alone and 1 associated with distant metastases. The overall cancer-specific survival was 95.4%, and the overall progression-free survival was 93%.

CONCLUSIONS

Enucleoresection reproduces the results of partial and radical nephrectomy with minimal morbidity. It is a safe and acceptable approach for elective nephronsparing surgery.

A prospective randomized EORTC intergroup phase 3 study comparing the complications of elective nephron-sparing surgery and radical nephrectomy for low-stage renal cell carcinoma

OBJECTIVES

This study compared the complications and the cancer control of elective nephron-sparing surgery (NSS) and radical nephrectomy (RN) in patients with a small (<or=5 cm), solitary, low-stage N0 M0 tumour suspicious for renal cell carcinoma (RCC) and a normal contralateral kidney.

METHODS

541 patients were randomised in a prospective, multicentre, phase 3 trial to undergo NSS (n=268) or RN (n=273) together with a limited lymph node dissection.

RESULTS

This publication reports only on the complications reported for both surgical methods. The rate of perioperative blood loss<0.5l was slightly higher after RN (96.0% vs. 87.2%) and the rate of severe haemorrhage was slightly higher after NSS (3.1% vs. 1.2%). Ten patients (4.4%), all of whom were treated with NSS, developed urinary fistulas. Pleural damage (11.5% for NSS vs. 9.3% for RN) and spleen damage (0.4% for NSS and 0.4% for RN) were observed with similar rates in both groups. Postoperative computed tomography scanning abnormalities were seen in 5.8% of NSS and 2.0% of RN patients. Reoperation for complications was necessary in 4.4% of NSS and 2.4% of RN patients.

CONCLUSIONS

NSS for small, easily resectable, incidentally discovered RCC in the presence of a normal contralateral kidney can be performed safely with slightly higher complication rates than after RN. The oncologic results are eagerly awaited to confirm that NSS is an acceptable approach for small asymptomatic RCC.

CT and MR Imaging of Complications of Partial Nephrectomy

The standard treatment for renal cell carcinoma for many years was radical nephrectomy, but in the past decade there has been a trend toward elective nephron-sparing surgery. Initially, partial nephrectomy was performed with an open surgical approach; more recently and with increasing frequency, a laparoscopic approach has been used in selected cases. Nephron-sparing surgery with either approach is more complex than is traditional radical nephrectomy and more frequently results in complications. The possible complications of partial nephrectomy include vascular, collecting system, and technical complications as well as recurrent tumor and infection. For prompt diagnosis and appropriate management of these complications, radiologists must be familiar with normal and abnormal features in the postoperative appearance of the kidney at computed tomography and magnetic resonance imaging.

Open partial nephrectomy with selective renal parenchymal control: A new reliable clamp

We describe our experience of open partial nephrectomy with a parenchymal clamp, the Reni-Clamp, in 30 patients from January 2002 to May 2005. The mean operative and clamping time was 150 and 27 minutes, respectively, and the blood loss was 150 mL. The Reni-Clamp enabled us to perform partial nephrectomy safely in all cases of polar or external edge renal tumor.

Renal tumors: technical success and early clinical experience with radiofrequency ablation of 18 tumors

PURPOSE

To evaluate the feasibility, safety, and technical efficacy of image-guided radiofrequency ablation (RFA) for the treatment of small peripheral renal tumors and to report our early results with this treatment modality.

METHODS

Twenty-two RFA sessions for 18 tumors were performed in 11 patients with renal tumors. Indications included coexistent morbidity, high surgical or anesthetic risk, solitary kidney, and hereditary predisposition to renal cell carcinoma. Ten patients had CT-guided percutaneous RFA performed on an outpatient basis. One patient had open intraoperative ultrasound-guided RFA. Technical success was defined as elimination of areas that enhanced at imaging within the entire tumor. With the exception of one patient with renal insufficiency who required gadolinium-enhanced MRI, the remaining patients underwent contrast-enhanced CT for post-treatment follow-up assessment. Follow-up was performed after 2-4 weeks and then at 3, 6, 12 months, and every 12 months thereafter.

RESULTS

Fourteen (78%) of 18 tumors were successfully ablated with one session. Three of the remaining four tumors required two sessions for successful ablation. One tumor will require a third session for areas of persistent enhancement. Mean patient age was 72.82 +/- 10.43 years. Mean tumor size was 1.95 +/- 0.79 cm. Mean follow-up time was 10.91 months. All procedures were performed without any major complications.

CONCLUSIONS

Our early experience with percutaneous image-guided radiofrequency ablation demonstrates it to be a feasible, safe, noninvasive, and effective treatment of small peripheral renal tumors.

The indications for partial nephrectomy in the treatment of renal cell carcinoma

Partial nephrectomy is performed more frequently for small, incidentally discovered, low-stage renal tumors. Importantly, one should distinguish the imperative indications for such surgery from the relative and elective indications, while taking contraindications to nephron-sparing surgery into account. The main advantage of partial nephrectomy over radical nephrectomy is the avoidance of renal insufficiency; the major disadvantages include the possibility of local recurrence and perioperative complications. In this article, the literature on nephron-sparing surgery was reviewed in order to put the management of renal cancer into a modern perspective.

Nephron-Sparing Surgery for Renal Cell Carcinoma: Detailed Analysis of Complications Over a 15-Year Period

PURPOSE

To assess the incidence of complications of conservative renal surgery for renal cell carcinoma in both elective and imperative indications, and its evolution over a 15 year period.

PATIENTS AND METHODS

From 1988 to 2003, 127 patients underwent partial nephrectomy or tumorectomy for renal cell carcinoma in our department. INDICATIONs were imperative in 42% (n = 53) and elective in 58% (n=74) of cases. Morbidity was retrospectively assessed according to four parameters: 1- Period of surgery: A, from 1988 to 1999 and B, from 2000 to 2003. 2- INDICATION: elective vs. imperative. 3- experience of surgeon: senior vs. junior. 4- Nature of complications: minor or major. Comparative analysis was conducted using Chi-square and Fischer exact tests.

RESULTS

Global incidence of complications was 30.7% (n = 39) corresponding to 18.1% minor (n = 23) and 12.6% (n = 16) major complications. Results show a moderate decrease of complication rate during Period B: 28.1% versus 32.9% during period A (p = 0.69). Complications occurred more frequently in imperative indications (49.1%) than in elective indications (17.6%) (p = 0.002), mostly regarding major complications (respectively 28.3% and 1.4%. (p < 0.001)). Overall re-intervention rate was 15.7%: 22.6% in imperative and 10.8% in elective indications (p = 0.008). Mean length of hospital stay was 14.1 days and significantly longer during period A (p = 0.003) and in imperative indications (p = 0.009).

CONCLUSION

In our study, conservative renal surgery has a significant rate of complications which is extremely variable regarding to different parameters. Most discriminating factor was indication: in imperative indications, we observed a high rate of major complications (28.3%) that we consider acceptable to prevent anephria in clearly informed patients. Major complications are exceptional in elective indications. Decreased incidence of complications during the later period (B) is modest, and the role played by systematic pedicular clampage is discussed. As results published in medical literature are difficult to compare, we agree with authors who recently proposed to standardize complications data analysis, using a gravity scale, in order to provide relevant information to patients about statistical risks before surgery.

Contrast-enhanced ultrasound evaluation of radiofrequency ablation of the kidney: reliable imaging of the thermolesion

BACKGROUND AND PURPOSE

Radiofrequency ablation (RFA) is limited by the inability to monitor progression of the thermal lesion. Contrast-enhanced ultrasonography (CEUS) imaging has considerable potential as a monitoring modality for RFA. We report our experience using CEUS to evaluate the lesion produced by RFA in a porcine model.

MATERIALS AND METHODS

Five pigs underwent laparoscopic RFA twice, spaced by a 1-week interval. Post- RFA ultrasound imaging was performed transcutaneously immediately after ablation. The kidneys were assessed for a contrast void corresponding to the ablated tissue. The kidneys were then harvested and the gross RFA lesions measured to compare lesion size with that measured using CEUS.

RESULTS

A clear lesion was identified at the site of each RFA application. As measured by CEUS, the acute lesions averaged 1.8 +/- 0.4, 1.7 +/- 0.4, and 1.8 +/- 0.3 cm in length, height, and width, respectively, compared with 2.0 +/- 0.5, 1.8 +/- 0.4, and 1.9 +/- 0.3 cm, respectively, by measurement in the gross specimen (P = 0.33, 0.13, and 0.44, respectively). At 1 week, the CEUS-measured dimensions of the lesions were 2.7 +/- 0.5, 2.6 +/- 0.6, and 2.6 +/- 0.6 cm, and the gross measurements of the lesion were 2.7 +/- 0.4, 2.7 +/- 0.9, and 2.6 +/- 0.4 cm (P = 0.75, 0.92, and 0.40, respectively).

CONCLUSIONS

Contrast-enhanced ultrasonography appears to be an accurate modality for immediate monitoring of RFA defects. Further study is necessary to assess the clinical utility of CEUS for monitoring RFA of small renal lesions.

Complications of Radical and Partial Nephrectomy in a Large Contemporary Cohort

PURPOSE

Standardized criteria for reporting the early complications of urological procedures are lacking. We reviewed the early complications of radical nephrectomy (RN) and partial nephrectomy (PN) in a large contemporary cohort using a standardized complication grading scale.

MATERIALS AND METHODS

Between 1995 and 2002, 1,049 patients underwent RN (66%) or PN (34%) for renal cortical neoplasm. Records were reviewed for perioperative complications. Complications were graded using a 5-tiered scale based on the severity of impact or intensity of therapy required.

RESULTS

A total of 235 complications occurred in 180 patients (17%). Overall 55% and 31% of complications were grade I and grade II, respectively. There were 3 perioperative deaths (0.2%). PN was not associated with more complications compared to RN when accounting for other variables. PN cases had more procedure related complications compared to RN (9% versus 3%, respectively, p = 0.0001) due to complications of urinary leak and the reintervention rate was subsequently higher (2.5% versus 0.6%, p = 0.02). All but 1 of the reinterventions for PN involved either endoscopy or radiology. By multivariate analysis operative time (p <0.0001) and solitary kidney (p = 0.06) were associated with procedure related complications of PN.

CONCLUSIONS

RN and PN are associated with low rates of serious morbidity and mortality. Compared to RN, PN is associated with higher rates of procedure related complications, the majority of which are minor. Overall, however, PN is not associated with more complications than RN.

Histopathology of surgically managed renal tumors: analysis of a contemporary series

OBJECTIVES

To review the pathologic findings of a contemporary series of surgically treated renal tumors suspicious for malignancy to assess the frequency of benign disease in the modern era. The extensive application of modern imaging techniques has led to an increase in the number of incidentally discovered solid renal masses, many of which are small. A significant proportion of small renal tumors are benign or are low-grade malignancies.

METHODS

The records of all patients at our institution who underwent treatment for a renal mass suspicious for malignancy between November 1999 and July 2002 were retrospectively reviewed.

RESULTS

A total of 173 patients with 186 renal tumors had pathologic information available for analysis. Of the 186 tumors, 48% were discovered incidentally. For masses 4 cm or less, the percentage of incidentally discovered tumors increased to 58%. The pathologic evaluation demonstrated malignancy in 160 (86%) and benignity in 26 (14%) overall. For tumors 4 cm or less, 18 (20%) of 90 were benign; for tumors between 4 and 7 cm, 8 (17%) of 47 benign. No tumors greater than 7 cm were benign. All renal cell carcinomas less than 2 cm in size were Fuhrman grade 1 or 2.

CONCLUSIONS

Small renal tumors, many of which are incidentally discovered, are often benign or are low-grade malignancies. For tumors 4 cm or less, the frequency of benign pathologic findings is greater than previously quoted in published reports. As a result, we recommend parenchymal-sparing approaches whenever possible.

The Effects of Radio Frequency Ablation on Renal Function and Blood Pressure

PURPOSE

Radio frequency ablation (RFA) is evolving as a nephron sparing treatment alternative for select patents with small renal tumors. The impact of ablated tissue on the remaining kidney parenchyma is unknown. To assess this impact we evaluated pretreatment and posttreatment serum creatinine (sCr), and blood pressure of patients treated with RFA with at least 6 months of followup.

MATERIALS AND METHODS

From our series of 69 tumors treated with RFA 25 patients with a total of 26 tumors and a minimum 6-month followup were identified. RFA was delivered percutaneously or laparoscopically depending on tumor location and patient preference. Blood pressure measurements and sCr levels were obtained at preoperative and postoperative office visits. Values for preoperative and postoperative systolic blood pressure, diastolic pressure and sCr were each compared. Estimated creatinine clearance was calculated for each patient before and after treatment, and compared.

RESULTS

No patient experienced new onset hypertension or worsening of existing hypertension. Likewise no changes in mean sCr and estimated creatinine clearance were observed.

CONCLUSIONS

Treatment with RFA does not appear to have an effect on renal function or blood pressure. RFA appears to be a medically safe therapy for patients with small renal tumors.

Two cases of pseudoaneurysm of the renal artery following laparoscopic partial nephrectomy for renal cell carcinoma: CT angiographic evaluation

Partial nephrectomy via a laparoscopic approach can be technically challenging, and associated vascular complications such as pseudoaneurysm may occur. CT with CT angiography is ideal for the noninvasive imaging of this process. This article reports two cases of pseudoaneurysm of the renal artery detected on CT as a complication of laparoscopic partial nephrectomy and demonstrates the usefulness of 3-D CT angiography in the evaluation of vascular pathology.

The role of partial nephrectomy for renal cell carcinoma in contemporary practice

Partial nephrectomy has proved to be a safe and effective treatment modality, even for patients with normal contralateral kidneys. The indications for elective partial nephrectomy continue to evolve as contemporary series demonstrate low morbidity approaching that of radical nephrectomy. Furthermore, patients who undergo partial nephrectomy have a significantly decreased risk of future renal insufficiency. As such, a rationale exists for expanding indications in an era of excellent technical outcomes and increased patient longevity. Characterization of newer diagnostic (three-dimensional imaging) and treatment (laparoscopic partial nephrectomy, cryosurgery) modalities will allow continued evolution of nephron-sparing techniques.

Imaging-guided percutaneous radiofrequency ablation of solid renal masses: techniques and outcomes of 38 treatment sessions in 32 consecutive patients

OBJECTIVE

The purpose of this study was to describe the treatment techniques and results of 38 consecutive imaging-guided percutaneous radiofrequency ablations of solid renal masses performed in 32 patients.

MATERIALS AND METHODS

Solid renal masses in 32 patients underwent 38 treatment sessions using imaging-guided percutaneous radiofrequency ablation. During 36 sessions, radiofrequency ablation was performed using CT guidance, and two, using sonographic guidance. The average patient age was 76 years (range, 52-87 years), and the average renal mass size was 2.6 cm (range, 1-5 cm). The average number of radiofrequency treatments per solid mass at each session was 2.4 (range, 1-6 treatments), and the average time per treatment was 9.2 min (range, 3-14 min). A single electrode was used in 12 sessions, and a cluster electrode was used in 26 sessions. The average follow-up time was 9 months (range, 1-36 months).

RESULTS

Twenty-six of 32 patients had successful treatment of the solid renal mass using percutaneous imaging-guided radiofrequency ablation after one treatment session. Successful treatment was defined as lack of enhancement of the treated region on follow-up CT. Six of 32 patients had residual enhancing tissue after the first treatment session and returned for a second session. Five of these six retreatments were successful. Masses requiring a second treatment session were significantly larger than masses treated in a single session (3.5 vs 2.4 cm, respectively; p = 0.0013). Two patients had perinephric hematomas (which did not require transfusion), and one patient developed a 5-mm skin metastasis at the electrode insertion site, which was resected without recurrence.

CONCLUSION

Percutaneous imaging-guided radiofrequency ablation shows promise in the treatment of solid renal malignancies.

Should there be a size limit for elective nephron-sparing surgery?

Nephron-sparing surgery (NSS) is a mandatory procedure for patients with solid renal masses who also have coexisting urologic or medical conditions that pose a threat to overall renal function. The excellent results observed with this procedure have led patients with normal contralateral kidneys to choose elective NSS as a treatment modality. However, the optimal selection criteria for NSS have not yet been defined. We review the developments in and recent results of NSS and discuss features critical in selecting patients for this procedure on an elective basis. Current data clearly support the use of elective NSS for localized solid renal masses under 4 cm in size.