Search

Purpose: Technetium-99m-sestamibi single-photon emission CT/x-ray CT is an emerging clinical tool to differentiate oncocytic tumors from renal cell carcinomas. We report data from a large institutional cohort of patients who underwent technetium-99m-sestamibi scans during evaluation of renal masses., Materials and Methods: Patients who underwent technetium-99m-sestamibi single-photon emission CT/x-ray CT between February 2020 and December 2021 were included in the analysis. Scans were defined as "hot" for oncocytic tumor when technetium-99m-sestamibi uptake was qualitatively equivalent or higher between the mass of interest and normal renal parenchyma, suggesting oncocytoma, hybrid oncocytic/chromophobe tumor, or chromophobe renal cell carcinoma. Demographic, pathological, and management strategy data were compared between "hot" and "cold" scans. For individuals who underwent diagnostic biopsy or extirpative procedures, the concordance between radiological findings and pathology was indexed., Results: A total of 71 patients (with 88 masses) underwent technetium-99m-sestamibi imaging with 60 (84.5%) patients having at least 1 "cold" mass on imaging and 11 (15.5%) patients exhibiting only "hot" masses. Pathology was available for 7 "hot" masses, with 1 biopsy specimen (14.3%) being discordant (clear cell renal cell carcinoma). Five patients with "cold" masses underwent biopsy. Out of 5 biopsied masses, 4 (80%) were discordant oncocytomas. Of the extirpated specimens, 35/40 (87.5%) harbored renal cell carcinoma and 5/40 (12.5%) yielded discordant oncocytomas. In sum, 20% of pathologically sampled masses that were "cold" on technetium-99m-sestamibi imaging still harbored oncocytoma/hybrid oncocytic/chromophobe tumor/chromophobe renal cell carcinoma., Conclusions: Further work is needed to define utility of technetium-99m-sestamibi in real-world clinical practice. Our data suggest this imaging strategy is not yet ready to replace biopsy.

Purpose: We describe what is to our knowledge a novel classification system for local recurrence after surgery of renal cell carcinoma. We assessed its prognostic implications using prospective, randomized controlled data., Materials and Methods: We queried the ASSURE (Sunitinib Malate or Sorafenib Tosylate in Treating Patients With Kidney Cancer That Was Removed By Surgery) (ECOG-ACRIN [Eastern Cooperative Oncology Group-American College of Radiology Imaging Network] E2805) trial data for patients with fully resected, intermediate-high risk, nonmetastatic renal cell carcinoma with local recurrence. We used certain definitions, including type I-single recurrence in a remnant kidney or ipsilateral renal fossa, type II-single recurrence in the ipsilateral vasculature, the ipsilateral adrenal gland or a lymph node, type III-single recurrence in other intra-abdominal soft tissues or organs and type IV-any combination of types I-III or multiple recurrences of a single type. Multivariable logistic regression and the log rank test were performed to identify clinicopathological predictors and compare survival, respectively., Results: Of the 1,943 patients 300 (15.4%) had local recurrence, which was type I, II, III and IV in 66 (22.0%), 97 (32.3%), 87 (29.0%) and 50 (16.7%), respectively. Surgical modality (minimally invasive vs open) and type of surgery (partial vs radical) did not predict any local recurrence. Five-year cancer specific survival and overall survival were worse in patients with type IV recurrence (each p <0.001). There was no difference in survival among patients with types I to III recurrence., Conclusions: In patients with intermediate-high risk nonmetastatic renal cell carcinoma local recurrence appears to be a function of biology more than of surgical modality or surgery type. The prognosis for solitary intra-abdominal local recurrences appear similar regardless of location (types I-III). Local recurrences involving multiple sites and/or subdivisions are associated with worse survival (type IV).

Purpose: The natural history of nonclear cell renal cell carcinoma following surgery with curative intent remains poorly defined with postoperative surveillance informed by guidelines largely intended for clear cell renal cell carcinoma. We evaluated relapse patterns and potential implications for post-nephrectomy surveillance in patients with nonclear cell renal cell carcinoma enrolled in the E2805 trial, the largest randomized trial of adjuvant antiangiogenic therapy of high risk renal cell carcinoma., Materials and Methods: We retrospectively analyzed the records of patients with completely resected nonclear cell renal cell carcinoma. Participants received up to 54 weeks of postoperative therapy with sunitinib, sorafenib or placebo and underwent surveillance imaging at standardized intervals for 10 years. For recurrence rates by site the cumulative incidence was estimated, accounting for competing risks. The adequacy of strict adherence to post-nephrectomy surveillance guidelines was evaluated., Results: A total of 403 patients with nonclear cell renal cell carcinoma were enrolled in the study. During a median followup of 6.2 years 36% of nonclear cell renal cell carcinomas recurred. Five-year recurrence rates were comparable for nonclear and clear cell renal cell carcinoma in the 1,541 patients, including 34.6% (95% CI 29.8-39.4) and 39.5% (95% CI 36.9-42.1), respectively. However, patients with nonclear cell renal cell carcinoma were significantly more likely to have abdominal sites of relapse (5-year recurrence rate 26.4% vs 18.2%, p = 0.0008) and significantly less likely to experience relapse in the chest (5-year recurrence rate 13.7% vs 20.9%, p = 0.0005). Current surveillance guidelines would potentially capture approximately 90% of relapses at any site., Conclusions: Nonclear cell renal cell carcinoma may show a distinct pattern of relapse compared to clear cell renal cell carcinoma. Our findings emphasize the importance of cross-sectional, long-term imaging in patients with high risk, resected, nonclear cell renal cell carcinoma.

Purpose: We evaluated the outcomes of surgical intervention and active surveillance in patients diagnosed with cystic renal cell carcinoma at our hypothesized radiological cutoff of greater than 50% cystic., Materials and Methods: We identified all 430 patients with a pathologically confirmed cystic renal mass that fit our criteria from 2000 to 2015. The 292 patients with a lack of computerized tomography, tumors less than 50% cystic on imaging, multifocal tumors and prior renal cell carcinoma were excluded from study. Patients were stratified into benign or malignant subgroups, and radiological, clinicopathological and oncologic features were determined. Univariate and multivariate associations between clinicoradiological parameters in each group were analyzed. We similarly reviewed the records of a separate cohort of patients treated with active surveillance for cystic renal cell carcinoma., Results: Of the 138 identified cases of cystic renal cell carcinoma 102 (73.9%) were renal cell carcinoma and 36 (26.1%) were benign masses. Of the tumors 77.5% were Fuhrman grade 1-2, 83.4% were stage pT2 or less and 65.9% showed clear cell histology. On univariate analysis male gender, a solid component and increasing Bosniak classification were significant for malignancy. In a separate cohort we identified 38 patients on active surveillance. The growth rate was 1.0 mm per year overall and 2.3 mm per year for the solid component. At a median followup of more than 4 years in all cohorts there was no evidence of recurrence or metastasis of cystic renal cell carcinoma., Conclusions: Patients with unifocal cystic renal cell carcinoma evaluated using a standardized radiological threshold of greater than 50% cystic had an excellent prognosis on active surveillance and after surgical resection., (Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Lymph node dissection may benefit patients at increased risk for lymph node metastases from renal cell carcinoma. Therefore, we evaluated the association of lymph node dissection with survival in patients at high risk undergoing radical nephrectomy for renal cell carcinoma., Materials and Methods: We identified 2,722 patients with M0 renal cell carcinoma who underwent radical nephrectomy with or without lymph node dissection at 2 international centers from 1990 to 2010. The associations of lymph node dissection with the development of distant metastases, and cancer specific and all cause mortality were evaluated using propensity score techniques and traditional multivariable Cox regression. Subset analyses were done to examine patients at increased risk of lymph node metastases., Results: Overall 171 patients (6.3%) had pN1 disease. Median followup was 9.6 years. Clinicopathological features were well balanced after propensity score adjustment. Lymph node dissection was not significantly associated with a reduced risk of distant metastases, or cancer specific or all cause mortality in the overall cohort, among patients with preoperative radiographic lymphadenopathy (cN1), or across an increasing probability of pN1 disease from 0.10 or greater to 0.50 or greater. Neither extended lymph node dissection nor the extent of lymph node dissection was associated with improved oncologic outcomes., Conclusions: The current analysis of a large, international cohort indicates that lymph node dissection is not associated with improved oncologic outcomes among patients at high risk who undergo radical nephrectomy for M0 renal cell carcinoma. This includes patients with radiographic lymphadenopathy (cN1) and across increasing probability thresholds of pN1 disease., (Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Prostate specific membrane antigen is expressed by the endothelium of many tumors. The aim of the study was to find a rationale for prostate specific membrane antigen based imaging and investigate the prognostic role of vascular prostate specific membrane antigen expression in patients with renal cell carcinoma., Materials and Methods: A total of 257 patients with renal cell carcinoma were included in study with a median followup exceeding 10.0 years. Prostate specific membrane antigen expression on tumor vessels was detected by immunohistochemistry. Vascular expression of FOLH1 gene (prostate specific membrane antigen) mRNA was investigated in clear cell carcinoma and papillary renal cell carcinoma using TCGA (The Cancer Genome Atlas) data., Results: Endothelial prostate specific membrane antigen protein expression was higher in clear cell than in papillary and chromophobe renal cell carcinoma. Higher grade and stage, metastatic and lethal clear cell renal cell carcinoma showed higher prostate specific membrane antigen expression in tumor vessels. On univariate and multivariate analysis the intensity of positive vs negative endothelial prostate specific membrane antigen protein expression was significantly associated with overall survival. TCGA based analyses confirmed the prognostic role of vascular expression of FOLH1 mRNA. The analyses also supported the usefulness of prostate specific membrane antigen based imaging in cases of clear cell but not papillary renal cell carcinoma., Conclusions: We provide a rationale for further development of prostate specific membrane antigen targeted imaging in patients with clear cell renal cell carcinoma. The prognostic role of prostate specific membrane antigen was determined at the protein level in clear cell renal cell carcinoma and at the mRNA level in clear cell and papillary renal cell carcinoma., (Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: The overall recurrence rate of T1 renal cell carcinoma is low. We evaluated abdominal imaging after partial nephrectomy based on current guidelines for T1 renal cell carcinoma surveillance., Materials and Methods: We retrospectively reviewed the records of patients with T1 renal cell carcinoma who underwent partial nephrectomy between 2006 and 2012 followed by abdominal imaging at our institution. Primary and secondary outcomes were the incidence and timing, respectively, of imaging diagnosed abdominal recurrences. A literature review was performed to summarize prior reports of recurrence incidence and timing after partial nephrectomy for T1 disease., Results: A total of 160 patients with stage T1a and 37 with T1b underwent partial nephrectomy. Seven patients had an abdominal recurrence, including 3 with local and distant recurrences, and 4 with a metachronous contralateral kidney recurrence. The incidence of abdominal recurrence detected by imaging was higher in the T1b than in the T1a group (10.8% vs 1.9%, p = 0.024). Although it was not significant, median time to recurrence was earlier in T1b vs T1a cases (13 vs 37 months, p = 0.480). In each group recurrences developed after 3 years of suggested guideline surveillance. In the literature combined with the current study the time to median recurrence for T1b vs T1a was 24 vs 29 months (p = 0.226)., Conclusions: Recurrences detected by abdominal imaging developed earlier and more frequently in T1b than in T1a cases. Future recommendations for surveillance strategies after partial nephrectomy should distinguish T1a from T1b with less intense frequency of imaging for T1a. A longer period of surveillance should be considered since recurrences can develop beyond 3 years., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: The detection of small renal masses is increasing with the use of cross-sectional imaging, although many incidental lesions have negligible metastatic potential. Among malignant masses clear cell renal cell carcinoma is the most prevalent and aggressive subtype. A method to identify such histology would aid in risk stratification. Our goal was to evaluate a likelihood scale for multiparametric magnetic resonance imaging in the diagnosis of clear cell histology., Materials and Methods: We retrospectively reviewed the records of patients with cT1a masses who underwent magnetic resonance imaging and partial or radical nephrectomy from December 2011 to July 2015. Seven radiologists with different levels of experience who were blinded to final pathology findings independently reviewed studies based on a predefined algorithm. They applied a clear cell likelihood score, including 1-definitely not, 2-probably not, 3-equivocal, 4-probably and 5-definitely. Binary classification was used to determine the accuracy of clear cell vs all other histologies. Interobserver agreement was calculated with the weighted κ statistic., Results: A total of 110 patients with 121 masses were identified. Mean tumor size was 2.4 cm and 50% of the lesions were clear cell. Defining clear cell as scores of 4 or greater demonstrated 78% sensitivity and 80% specificity while scores of 3 or greater showed 95% sensitivity and 58% specificity. Interobserver agreement was moderate to good with a mean κ of 0.53., Conclusions: A clear cell likelihood score used with magnetic resonance imaging can reasonably identify clear cell histology in small renal masses and may decrease the number of diagnostic renal mass biopsies. Standardization of imaging protocols and reporting criteria is needed to improve interobserver reliability., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: We evaluated the postoperative outcome of cystic renal cell carcinoma defined on preoperative computerized tomography. We also sought to find the optimal cutoff of the cystic proportion in association with patient prognosis., Material and Methods: In this institutional review board approved study with waiver of informed consent, 1,315 patients were enrolled who underwent surgery for a single renal cell carcinoma with preoperative computerized tomography. The cystic proportion of renal cell carcinoma was determined on computerized tomography. The optimal cutoff of the cystic proportion was explored regarding cancer specific survival. Renal cell carcinomas were categorized as cystic or noncystic renal cell carcinoma according to a conventional cutoff (ie cystic proportion 75% or greater) and an optimal cutoff. Postoperative outcomes were then compared between the 2 groups. Multivariate Cox regression analysis was performed to determine the independent predictor of cancer specific survival., Results: Of the 1,315 lesions 107 (8.1%) were identified as cystic renal cell carcinoma according to a conventional cutoff. The postoperative outcome of cystic renal cell carcinoma was significantly better than that of noncystic renal cell carcinoma (p <0.001). Neither metastasis nor recurrence developed after surgery in patients with cystic renal cell carcinoma. In association with the cancer specific survival rate, the optimal cutoff of the cystic proportion was 45% and 197 cases (15.0%) were accordingly defined as cystic renal cell carcinoma. On Cox regression analysis, a cystic proportion of 45% or greater of the renal cell carcinoma was an independent predictor of a favorable outcome regarding cancer specific survival (HR 0.34, p = 0.03)., Conclusions: Cystic renal cell carcinoma defined on preoperative computerized tomography is associated with low metastatic potential and favorable outcomes after surgery. Particularly, a cystic proportion of 45% or greater is an independent prognostic factor for favorable survival., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Followup protocols after the surgical management of renal cell carcinoma lack clear evidence linking the intensity of imaging surveillance to improved outcomes. In this context we characterized the relationship between surveillance imaging intensity and cancer specific survival., Materials and Methods: Using SEER-Medicare data we identified 7,603 men with renal cell carcinoma treated surgically between 2004 and 2009. Multivariable negative binomial regression analysis was performed to assess the relationship between patient level characteristics and the variation in imaging intensity. We modeled the association between kidney cancer specific mortality and imaging intensity using Fine and Gray proportional subdistribution hazards regression with other cause death treated as a competing risk for 2 separate followup periods (15 and 36 months)., Results: More than 40% of patients in the short interval cohort and more than 50% in the intermediate interval group underwent no chest imaging during the evaluated survivorship period. More than 30% of patients in both followup periods had no abdominal imaging tests performed. Overall, followup imaging did not appear to confer an improvement in disease specific survival compared to undergoing no imaging in the 2 survivorship periods., Conclusions: There remains considerable variation in the posttreatment surveillance regimen for patients with renal cell carcinoma in the United States. More importantly, this study raises important questions regarding the link between posttreatment surveillance imaging and survival., (Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: The overall incidence of pulmonary metastasis of T1 renal cell carcinoma is low. We evaluated the usefulness of chest x-rays based on the current AUA (American Urological Association) guidelines and NCCN Guidelines® for T1a renal cell carcinoma surveillance., Materials and Methods: Between 2006 and 2012, 258 patients with T1a renal cell carcinoma were treated with partial nephrectomy, radical nephrectomy or radio frequency ablation with surveillance followup at our institution. A retrospective chart review was performed to identify demographics, pathological findings and surveillance records. The primary outcome was the incidence of asymptomatic pulmonary recurrences diagnosed by chest x-ray in cases of T1a disease. Our secondary outcome was a comparison of diagnoses by treatment modality (partial nephrectomy, radical nephrectomy or radio frequency ablation)., Results: Pulmonary metastases developed in 3 of 258 patients (1.2%) but only 1 (0.4%) was diagnosed by standard chest x-ray surveillance. Median followup in the entire cohort was 36 months (range 6 to 152) and 193 of 258 patients (75%) had greater than 24 months of followup. A mean of 3.3 surveillance chest x-rays were completed per patient. When assessed by treatment type, there was no significant difference in the recurrence rate for partial nephrectomy (0 of 191 cases), radical nephrectomy (0 of 22) or radio frequency ablation (1 of 45 or 2.2%) (p = 0.09)., Conclusions: Chest x-rays are a low yield diagnostic tool for detecting pulmonary metastasis in patients treated for T1a renal cel carcinoma. Treatment mode does not appear to influence the need for chest x-ray surveillance., (Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: We determined the role of tumor enhancement on dynamic enhanced computerized tomography for differentiating pathological characteristics., Materials and Methods: A total of 149 patients with renal tumor underwent dynamic enhanced computerized tomography at our university from June 2007 to November 2011. Tumors were treated surgically and pathological evaluation was done. Precontrast and postcontrast HU values, and the difference were recorded. Postcontrast HU evaluations were done at the nephrographic phase of the procedure. Tumor HU values were compared according to histological subtype, tumor grade and pathological stage., Results: Mean ± SD patient age was 57 ± 13 years and mean tumor size was 4.8 ± 2.7 cm. Postcontrast HU and contrast difference values were significantly lower in the malignant group. A cutoff HU value of 138 HU (mean AUC 0.893 ± 0.027, 95% CI 0.84-0.94) differentiated renal cell cancer from oncocytoma with 88% sensitivity and 87% specificity. Low and high grade cases demonstrated similar precontrast and postcontrast HU, and contrast difference values. These enhancement parameters were significantly lower for higher stage (pT2-3) renal cell cancer than for pT1. We detected higher postcontrast values (mean 62 ± 14 vs 56 ± 39 HU, p = 0.011) and contrast difference values (mean 92 ± 15 vs 82 ± 42 HU, p = 0.034) for high grade than for low grade renal cell cancer in patients with tumors 4 cm or less., Conclusions: The degree of enhancement on computerized tomography helps differentiate tumor characteristics. These outcomes may help the clinician with prognostic evaluation and may augment the role of computerized tomography in therapeutic planning., (Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Patients undergoing serial cross-sectional abdominal imaging to evaluate abdominal symptomatology may have a renal tumor develop during followup of an unrelated disease process. Evaluation of such patients provides an opportunity to further define the radiographic inception, natural history and growth patterns of renal tumors., Materials and Methods: Renal tumor databases from 2 institutions were reviewed for patients in whom an enhancing renal tumor developed despite a prior normal cross-sectional radiographic examination of the kidneys. Variables evaluated included age, gender, tumor size at presentation, calculated tumor growth rate from negative scan to radiographic presentation and pathology in patients undergoing definitive treatment., Results: We identified 36 patients with an average age of 65 years (range 44 to 82). Mean tumor size on presentation was 2.3 cm (range 1.0 to 5.0). The presumed absolute growth rate based on the timing of the initial negative imaging study and tumor diameter at presentation was significantly greater than the observed absolute growth rate after tumor detection (0.71 vs 0.039 cm per year, p = 0.028). No difference was noted between presumed and observed tumor growth based on absolute change in tumor volume (1.44 vs 5.37 cm(3) per year, p = 0.203). Presumed relative growth rates based on tumor diameter (665% vs 23% per year) and volume (1,397% vs 169% per year) were significantly greater than observed relative growth rates (p = 0.005 and p = 0.013, respectively)., Conclusions: The presumed growth rate of the tumors was significantly greater than the observed growth rate, suggesting that tumor growth rates do not follow a linear pattern throughout their development and progression., (Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: We investigated the effect of sunitinib on locally advanced primary renal carcinoma tumors and the ability to facilitate subsequent surgery., Materials and Methods: Patients with an unresectable primary renal tumor, with or without distant metastases, received 50 mg sunitinib with continuous daily dosing in a phase II trial. Computerized tomography was performed every 12 weeks to determine surgical resectability. The primary end point of the trial was the percentage of patients with renal cell carcinoma and initially unresectable primary tumors who could undergo nephrectomy after sunitinib therapy., Results: Of 30 patients enrolled in the study (19 with distant metastases) 28 (35 total renal tumors) were evaluable for response. The median change in primary renal cell carcinoma tumors was a 22% decrease, corresponding to a median absolute reduction of 1.2 cm. The median reduction in primary renal cell carcinoma tumors of clear cell histology was -28% (absolute reduction 1.7 cm) compared to a 1.4% increase (0.1 cm absolute increase) in nonclear cell tumors. Of these patients 13 (45%) met the primary end point of being able to undergo nephrectomy after preoperative sunitinib. All patients had viable renal cell carcinoma in the surgical specimen and surgical morbidity was consistent with prior experience of nephrectomy in patients without preoperative therapy., Conclusions: Sunitinib as initial therapy in patients with locally advanced features of the primary tumor was feasible and resulted in an antitumor effect that enabled subsequent surgery in a subset of patients. Further prospective study is required to refine the most suitable application of this approach., (Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: Surgical resection remains the most effective treatment in patients with pulmonary metastasis of renal cell carcinoma. To our knowledge the prognostic significance of mediastinal and hilar lymph node metastasis during pulmonary metastasectomy in patients with renal cell carcinoma is unknown. We analyzed the value of computerized tomography to predict mediastinal/hilar lymph node involvement as well as the impact of systematic lymphadenectomy on survival in patients with pulmonary renal cell carcinoma metastasis., Materials and Methods: We analyzed survival in 110 patients who underwent resection of pulmonary metastasis of renal cell carcinoma using the Kaplan-Meier method. Multivariate analysis was done by Cox regression analysis., Results: Lymph node metastasis was histologically proved in 35% of patients. Metastasis was not associated with initial tumor grade, lymph node status, the number of pulmonary metastases or recurrent pulmonary metastasis. Computerized tomography had 84% sensitivity and 97% specificity to predict lymph node metastasis. Sensitivity was markedly better for detecting mediastinal than hilar lymph node metastasis (90% vs 69%). Patients with lymph node metastasis had significantly shorter median survival than patients without lymph node metastasis (19 vs 102 months, p <0.001). Multivariate analysis revealed that tumor infiltrated mediastinal lymph nodes were an independent prognostic factor for patient survival. Match paired analysis showed that after lymph node dissection patients showed a trend toward improved survival., Conclusions: Mediastinal and hilar lymph node metastases significantly correlate with decreased survival. Systematic lymphadenectomy provides valuable information on staging and prognosis in patients with pulmonary metastasis of renal cell carcinoma, and may prolong survival., (Copyright © 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: New advances in computerized tomography, including multidetector computerized tomography with 3-dimensional reformatting has recently called into question the absolute need for magnetic resonance imaging for evaluating renal cell carcinoma with suspected venous involvement. We assessed the accuracy of multidetector computerized tomography for predicting tumor thrombus and the level of venous involvement in patients with renal cell carcinoma., Materials and Methods: We retrospectively reviewed clinical and pathological features in 41 patients with renal cell carcinoma who underwent staging multidetector computerized tomography before surgery. Multidetector computerized tomography findings regarding the presence and level of tumor thrombus were compared to findings at surgery and at final pathological evaluation. All multidetector computerized tomography studies were read by a single radiologist (EKF) before surgery., Results: When excluding patients with segmental venous involvement only, the concordance rate between multidetector computerized tomography and pathological findings was 84%. Multidetector computerized tomography accurately predicted the level of tumor thrombus in 26 of 27 patients (96%). Four cases of negative multidetector computerized tomography findings were up staged to renal vein involvement based on pathological findings. All 4 patients had early distal thrombi that did not change operative management., Conclusions: Multidetector computerized tomography with 3-dimensional mapping is an effective imaging modality for accurately characterizing the level of venous thrombus in patients with renal cell carcinoma. This modality effectively identified patients with clinically significant venous thrombus. Patients with renal cell carcinoma in whom multidetector computerized tomography fails to detect tumor thrombus are unlikely to have a tumor thrombus found at surgery that would change the surgical approach.

Purpose: We determined the risk of arteriovenous fistula after en bloc ligation of the renal hilum., Materials and Methods: A prospective evaluation of all patients who underwent en bloc ligation of the renal hilum during nephrectomy for malignant disease was performed. Pertinent operative data were recorded and patients were followed for clinical evidence of arteriovenous fistula formation, including hypertension, abdominal bruit and new onset congestive heart failure. Patients with at least 12 months of followup underwent computerized tomographic arteriography to assess arteriovenous fistula formation., Results: A total of 94 patients underwent en bloc renal hilar ligation during open (43) and laparoscopic (51) nephrectomy using a 45 mm titanium endovascular stapler. Of this cohort 11 patients were lost to followup and 3 died of disease. The remaining 80 patients were followed an average of 35.2 months with no clinical evidence of arteriovenous fistula formation. Specifically there was no statistically significant difference in preoperative and postoperative blood pressure (p = 0.18 and 0.62, respectively), no evidence of abdominal bruit on examination and no new onset congestive heart failure. A total of 32 had increased serum creatinine and, therefore, they were excluded from followup computerized tomographic arteriography. Eight patients had a followup of less than 1 year and they were not yet eligible for evaluation. In the 40 patients who underwent computerized tomographic arteriography no fistulas were noted., Conclusions: Based on clinical followup and prospective radiographic evaluation there appears to be a low risk of arteriovenous fistula formation after en bloc ligation of the renal hilum using a titanium endovascular stapler.

Purpose: We evaluated the results, accuracy and clinical incidence of our standard procedure of percutaneous biopsy for solid renal masses., Materials and Methods: From March 1999 to April 2005, 119 percutaneous core biopsies of renal masses were performed. Biopsies were proposed when there was no formal evidence for a carcinoma diagnosis on computerized tomography., Results: Benign lesions were diagnosed in 24 biopsies (20.1%), including oncocytoma in 13, angiomyolipoma in 5 and chronic pyelonephritis in 5. Malignancy was identified in 70 biopsies (58.8%), including 57 renal carcinomas (conventional renal cell in 41, papillary in 12 and chromophobe in 4), 4 transitional cell carcinomas, 8 metastases and 1 lymphoma. For 25 biopsies (21%) no accurate diagnosis was possible, including 12 that showed inflammatory tissue and 13 with normal or necrotic tissue. These inconclusive biopsies prompted repeat biopsy in 13 patients, in whom a total of 11 malignant lesions were diagnosed. A total of 64 nephrectomies were performed with a biopsy accuracy for histopathological tumor type and Fuhrman nuclear grade of 86% and 46%, respectively. A period of watchful waiting was proposed for 31 patients (34.2%) and no renal malignancies were found. Computerized tomography showed stabilization or disappearance of the initial renal mass., Conclusions: Percutaneous renal tumor biopsies are safe, cost-effective and often conclusive for an acute histological diagnosis. This procedure could be decisive for choosing the optimal treatment, particularly to avoid nephrectomy for benign lesions. Biopsies should not be considered a routine procedure but they could be indicated when there is a lack of radiological evidence in elective patients.

Purpose: Active surveillance of small incidental renal masses is associated with slow radiographic growth and a low risk of metastatic progression. Radiographic tumor size, in the absence of histological data, is the only prognostic indicator available when considering active surveillance. To better define the relationship between tumor size and the metastatic potential of small renal masses, we investigated whether radiographic tumor size predicts for the presence of synchronous metastases in renal cell carcinoma., Materials and Methods: We reviewed our institutional tumor registry to identify sporadic pathologically verified renal cell carcinoma treated during an 8-year period. We analyzed data regarding primary tumor size and the presence of biopsy proven synchronous metastatic disease at presentation. All N+M0 and nonpathologically confirmed M+ disease was excluded from analysis., Results: We compared 110 cases of renal cell carcinoma with biopsy proven synchronous metastatic disease at presentation to 250 controls with clinically localized renal cell carcinoma. Tumors associated with synchronous metastasis were significantly larger than localized lesions (median 8.0 cm [range 2.2 to 20.0] vs 4.5 cm [range 0.3 to 17.5], p <0.0001). The probability of synchronous metastasis increased with increasing primary tumor size (p <0.0001). There were no patients with tumors 2 cm or smaller who presented with biopsy confirmed metastatic disease and less than 5% (5 of 110) of all synchronous metastasis occurred in tumors 3.0 cm or smaller. Logistic regression models determined that the odds of synchronous metastasis increased by 22% for each 1 cm increase in tumor size., Conclusions: Radiographic tumor size is a significant clinical predictor of the presence of biopsy proven synchronous metastatic renal cell carcinoma. In our series the odds of presenting with synchronous, biopsy proven metastatic disease increased by 22% with each 1 cm increase in tumor size. A 100% odds increase, or doubling of the risk of metastasis, occurs with a 3.5 cm increase in primary tumor size. These data have important implications for extent of disease evaluations in patients with large tumors and for the active surveillance of small enhancing renal masses.

Purpose: The natural history of small renal masses is generally to slowly increase in size. However, a subset of lesions does not show radiographic growth. We compared clinical, radiographic and pathological characteristics of enhancing renal masses under active surveillance with zero net radiographic growth vs those with positive growth., Materials and Methods: We identified 106 enhancing renal masses that were observed for 12 months or greater. Lesions were grouped according to growth characteristics. Group 1 consisted of lesions demonstrating zero or negative growth. Group 2 tumors showed positive growth during surveillance. Clinical, radiographic and pathological parameters were then compared. A MEDLINE search was performed regarding zero growth lesions during observation for suspected renal cell carcinoma in the world literature., Results: Group 1 consisted of 35 lesions (33%) with a median growth rate of 0.0 cm yearly. Group 2 included 70 lesions (67%) showing growth at 0.31 cm yearly (p<0.0001). No differences were detected with regard to patient age (p=0.96), lesion size (p=0.41), solid/cystic appearance (p=1.00) or the incidental detection rate (p=0.38). While 17% of group 1 lesions (6 of 35) underwent intervention, 51% (36 of 71) in group 2 were ultimately treated (p=0.001). Pathological assessment showed a similar incidence of malignancy in groups 1 and 2 (83% and 89%, respectively, p=0.56). A literature review revealed that 78 of 295 observed lesions (26%) failed to demonstrate radiographic growth., Conclusions: We were unable to identify definable clinical characteristics to predict the future growth of enhancing renal masses under active surveillance. Our analysis demonstrated that 26% to 33% of these tumors do not demonstrate growth at 29 months median followup. These lesions have similar rates of malignancy compared to growing lesions and rates of progression to metastatic disease are similarly low. A brief period of active surveillance may be feasible with treatment limited to lesions that increase in size.

Purpose: Traditional imaging techniques cannot differentiate among benign, indolent and malignant renal neoplasms. Since conventional clear cell carcinomas are highly vascular, we used preoperative color and/or power Doppler ultrasonography to evaluate the association between vascular flow in a renal mass and surgical pathology., Materials and Methods: Nephrectomies performed at our institution between January 2001 and December 2004 were retrospectively evaluated. Any detection of flow in the renal mass on color Doppler ultrasonography was defined as vascular flow. A prospective validation study was then performed from January 2005 to October 2005 and a nomogram was constructed to predict clear cell histology., Results: Of 299 renal lesions in the retrospective cohort 210 (70%) had evidence of vascular flow, including 156 of 169 conventional clear cell carcinomas (92%) (p <0.0001). On logistic regression analysis vascular flow was associated with conventional clear cell histology (OR 16.9, 95% CI 8.7-32.8; p <0.0001). This finding was validated prospectively in 97 patients. Vascular flow was detected in 54 of 65 renal masses (83%) with conventional clear cell histology (p <0.0001), which was associated with an OR of 10.8 (95% CI 4.0-29.0; p <0.0001). A nomogram incorporating vascular flow along with clinical variables (clinical size, patient sex and age) to predict conventional clear cell histology was constructed on the retrospective cohort and validated on the prospective data set (concordance index 0.82 and 0.76, respectively)., Conclusions: Vascular flow detected by color Doppler ultrasonography is strongly associated with conventional clear cell histology. A nomogram incorporating vascular flow on color Doppler ultrasonography and clinical parameters may aid in the preoperative characterization of renal lesions.

Purpose: We determined the incidence of benign renal lesions in patients undergoing definitive surgery for localized renal masses 7 cm or less in maximum radiological diameter, and assessed preoperative and clinical parameters associated with benign histology., Materials and Methods: The records of 1,184 patients who underwent consecutive partial or radical nephrectomies between January 2000 and January 2005 were retrospectively reviewed. We excluded 208 patients with lesions more than 7 cm in maximum radiological diameter, 17 with evidence of renal vein or vena caval invasion, 75 with suspected or documented metastatic disease, 28 with a history of renal cell carcinoma and 41 with no available imaging. Logistic regression was done to determine clinical factors associated with benign renal masses, including radiological tumor size, cystic vs solid appearance, patient sex, age, presenting symptoms and race., Results: Of 815 nephrectomies in our data set 134 (16.4%) were associated with benign lesions, including oncocytoma in 87 (10.7%), angiomyolipoma in 17 (2%), simple cysts in 10 (1.2%), metanephric adenoma in 8 (1%), cystic nephroma in 5 (0.6%) and other in 7. On multivariate logistic regression analysis only sex was significantly associated with benign histology with females having an OR of 1.8 (95% CI 1.2 to 2.6, p = 0.002). Tumor size was not independently associated with benign histology (p = 0.13)., Conclusions: A significant number (16.4%) of benign lesions less than 7 cm in radiological diameter were operated on based on suspicious preoperative imaging. Women had almost twice the likelihood of having a benign lesion.

Purpose: We assessed the degree of interobserver and intra-observer variability in the size measurement of small renal tumors with computerized tomography., Materials and Methods: A total of 29 renal masses from 21 patients were reviewed independently by 3 radiologists on computerized tomography performed with 5 mm collimation and a reconstruction interval of 2.5 mm. Measurements were made of the largest axial dimension (X), perpendicular axial dimension (Y) and slice direction (Z) with double reads performed in a subset of patients. The predicted 95% CI was calculated for each measure, assuming different readers and the same reader., Results: The predicted error bounds for a single renal mass measurement in the X axis were +/-3.1 mm when considering multiple readers and +/-2.3 mm for a single reader. In the X axis 78 of the 87 measurements (90%) were within 2 mm of the average measure. Smaller variances in measurements were seen with single reader repeat measurements than with multiple readers. Highest variances were seen in the Z axis. Measurements of volume and cross-sectional area showed a higher degree of variance., Conclusions: When comparing independent computerized tomography readings done with 5 mm collimation and a 2.5 mm reconstruction interval, a size change in the largest axial dimension of a renal mass of less than 3.1 mm between different radiologists and less than 2.3 mm for the same radiologist should be viewed with caution because it is within the range of measurement variability.

Purpose: We evaluated the factors that influenced the initial success rate and complication rate of percutaneous computerized tomography guided cryoablation of localized renal cell carcinoma of clinical stage T1N0M0., Materials and Methods: A total of 21 patients with a mean age of 71.5 years and a pathological diagnosis of renal cell carcinoma were treated with percutaneous computerized tomography guided cryoablation under conscious sedation on an outpatient basis. We retrospectively reviewed clinical data, tumor characteristics, techniques and results. Tumors with complete loss of contrast enhancement were considered successfully treated., Results: A total of 21 patients with 23 tumors underwent 25 cryoablation sessions. The mean intraoperative computerized tomography scan tumor size was 2.1 cm (range 0.5 to 4.3) and the mean ice ball size was 4.1 cm (range 2.2 to 7.2). Of the patients 82.6% (19 of 23) had a single treatment. Patients were followed with postoperative scans of 4.6 to 18.3 months (mean 12.3). There were 2 recurrences. The rate of successful complete tumor ablation was influenced by various factors. Tumor location and size were the major determinants for achieving tumor eradication., Conclusions: Percutaneous renal cryoablation using computerized tomography imaging proved to be a successful technique for guiding probe placement and monitoring ice ball formation. Patient selection based on tumor size and location may aid in improved outcomes. Further study and followup are necessary to determine long-term oncological efficacy.

Purpose: Ablative therapy for renal masses has been criticized because the entire tumor cannot be evaluated pathologically after the procedure. Diagnosis depends on imaging findings and the results of percutaneous needle biopsies, which may be nondiagnostic in up to 21% of cases. We determined outcomes in patients undergoing ablation who had nondiagnostic biopsies at the time of the procedure., Materials and Methods: A total of 79 patients (88 renal masses) underwent percutaneous computerized tomography guided biopsy and ablation of a renal mass under conscious sedation. Patients with nondiagnostic biopsies were identified and the medical records were reviewed retrospectively. All patients had an enhancing renal mass on preoperative computerized tomography or magnetic resonance imaging and all underwent postoperative contrast imaging to evaluate persistent viable tumor., Results: A total of 19 patients (20 tumors) with nondiagnostic percutaneous biopsy (22.7% or 20 of 88) were included in the study. No serious complications occurred. Tumors were treated with frequency ablation (12) or cryoablation (7). In 17 patients (89.5%) post-procedure imaging confirmed the absence of contrast enhancement at a median followup of 27.3 months (range 3 weeks to 56 months). In 2 cases (10.5%) post-procedure imaging showed a residual renal mass or recurrence with enhancement, suggesting that the original percutaneous biopsy result was false negative. In 1 patient residual tumor was identified on initial post-ablation imaging and the patient underwent laparoscopic partial nephrectomy. In another patient recurrence was diagnosed 30 months after ablation and the patient underwent laparoscopic radical nephrectomy. Although there was a nondiagnostic percutaneous biopsy in each case, pathological findings in the subsequent surgical specimen confirmed renal cell carcinoma., Conclusions: Nondiagnostic percutaneous biopsy at renal tumor ablation does not obviate the need for standard post-procedure imaging followup. Of patients with nondiagnostic biopsies in this series 10.5% still harbored viable renal cell carcinoma after percutaneous ablation.

Purpose: Partial nephrectomy for hilar tumors represents a technical challenge not only for laparoscopic, but also for open surgeons. We report the technical feasibility and perioperative outcomes of laparoscopic partial nephrectomy (LPN) for hilar tumors., Materials and Methods: Between January 2001 and September 2004, 25 of 362 patients (6.9%) undergoing LPN for tumor, as performed by a single surgeon, had a hilar tumor. We defined hilar tumor as a tumor located in the renal hilum that was demonstrated to be in actual physical contact with the renal artery and/or renal vein on preoperative 3-dimensional computerized tomography. En bloc hilar clamping with cold excision of the tumor, including its delicate mobilization from the renal vessels, followed by sutured renal reconstruction was performed routinely., Results: Laparoscopic surgery was successful in all cases without any open conversions or operative re-interventions. Mean tumor size was 3.7 cm (range 1 to 10.3), 4 patients (16%) had a solitary kidney and the indication for LPN was imperative in 10 patients (40%). Pelvicaliceal repair was performed in 22 patients (88%), mean warm ischemia time was 36.4 minutes (range 27 to 48), mean blood loss was 231 cc (range 50 to 900), mean total operative time was 3.6 hours (range 2 to 5) and mean hospital stay was 3.5 days (range 1.5 to 6.7). Histopathology confirmed renal cell carcinoma in 17 patients (68%), of whom all had negative margins. In 2002 or earlier hemorrhagic complications occurred in 3 patients (12%). No kidney was lost for technical reasons., Conclusions: LPN can be performed in select patients with a hilar tumor. The technical feasibility reported further extends the scope of LPN. To our knowledge the initial experience in the literature is reported.

Purpose: We describe our experience with and results of percutaneous computerized tomography guided radio frequency ablation (RFA) for small (less than 4 cm) renal tumors at a 2-year mean followup., Materials and Methods: A total of 49 patients (60 renal tumors) with a mean age of 63.9 years underwent percutaneous RFA. Indications for RFA were severe comorbidities or previous abdominal surgery precluding operative management, or hereditary conditions predisposing to multiple tumor recurrence. Persistent enhancement on initial followup imaging was considered incomplete treatment and all such patients underwent biopsy and were offered repeat RFA. Enhancement or enlargement on subsequent imaging was considered tumor recurrence and these patients were counseled regarding further therapy., Results: Three patients (4 tumors) were excluded from evaluation due to death from unrelated causes or loss to followup. A total of 46 patients (56 tumors) were available for evaluation at a mean followup of 27.5 months (range 12 to 48). Six tumors were incompletely treated with the first RFA and successfully treated with a second session. Recurrences after successful initial treatment were seen in 3 of 46 patients. These recurrences developed 24, 25 and 31 months following RFA, respectively, and all occurred in patients with a central tumor of 3.0 cm or greater. Overall local control was achieved in 94.6% of tumors (53 of 56)., Conclusions: RFA is an emerging alternative treatment modality for small renal tumors. Larger (greater than 3.0 cm) central tumors represent unique technical challenges, making these tumors more prone to recurrence. Long-term followup is needed to establish the oncological durability of this technique.

Purpose: We differentiated renal cell carcinoma subtypes using multislice computerized tomography (CT)., Materials and Methods: We reviewed the CT images of 87 patients with renal cell carcinoma. Three subtypes of renal cell carcinoma were noted, including clear cell in 37 cases, papillary in 26 and chromophobe in 24. Biphasic CT (unenhanced, corticomedullary and excretory phases) was done in all patients. We compared patient age and sex, tumor size, enhancement degree and pattern (homogeneous, heterogeneous and predominantly peripheral), the presence or absence of calcification or cystic degeneration (necrotic or hemorrhagic areas within the tumor) and tumor spreading patterns, including perinephric change, venous invasion and lymphadenopathy, in the 3 subtypes., Results: The degree of enhancement was significantly different among the 3 subtypes in the corticomedullary and excretory phases (p <0.001). Cystic degeneration was more evident in the clear cell subtype than in the other subtypes regardless of tumor size (p <0.001). A hypervascular pattern (higher tumor enhancement after contrast material injection due to higher vascularity) was noted in 48.6% of clear cell subtype in comparison to 15.4% of papillary and 4.2% of chromophobe subtypes (p <0.001). The chromophobe subtype showed homogeneous enhancement in 75% of cases in comparison to 45% and 65% of clear cell and papillary subtypes (p >0.05). Calcification was evident in 21.6%, 23.1% and 25% of clear cell, papillary and chromophobe subtypes, respectively (p >0.05)., Conclusions: To differentiate the subtypes of renal cell carcinoma the degree of enhancement is the most valuable parameter. The presence or absence of cystic degeneration, vascularity and enhancement patterns can serve supplemental role in differentiating renal cell carcinoma subtypes.

Purpose: Pathological stage has been the most widely used prognosticator for evaluating surgically managed cases of renal cell carcinoma. Minimally invasive surgical approaches are being increasingly used to treat small masses for which traditionally pathological information is lacking (morcellation) or absent (radio frequency ablation or cryoablation). Preoperative cross-sectional imaging by computerized tomography (CT) or magnetic resonance imaging has been used to stage renal tumors clinically but it can lead to variances with traditional pathological staging systems, particularly with respect to microscopic invasion beyond the renal capsule. In this study we assessed whether radiographically staged clinical T1 lesions that were pathological T1 behave differently than those that were clinical stage T1 and up staged to pT3a., Materials and Methods: The records of 296 patients who underwent surgical treatment for renal cell carcinoma at The Johns Hopkins Hospital between 1990 and 1999 were retrospectively reviewed. All patients had undergone preoperative CT or magnetic resonance imaging, which was used to assign a clinical stage and size (largest diameter) to each tumor in accordance with the 1997 TNM staging system. Following surgical resection pathological stage, size and tumor grade were determined. Only the 186 patients with clinical T1 tumors were included in this analysis., Results: Of the 186 patients who were clinically found to have T1 lesions 125 (67%) had pathological T1 and 57 (31%) had pathological T3a lesions. All surgical margins and lymph nodes were negative at surgical resection. Mean tumor size +/- SD was 3.9 +/- 1.5 cm for pT1 lesions and 3.8 +/- 1.5 cm for pT3a lesions. When comparing these pathological groups using Kaplan-Meier analysis, 5-year recurrence-free survival was not statistically different in patients with pT1 and pT3a lesions (90.6 and 97.5%, respectively)., Conclusions: Patients in whom the initial classification of T1 renal cell carcinoma by CT was up graded to T3a on pathological analysis (invasion of fat within Gerota's fascia) showed the same recurrence-free survival rate as patients with pathologically confirmed T1 lesions. Thus, smaller tumors (less than 7 cm) that are up graded to T3a based on capsule invasion behave much like T1 tumors and exact pathological T staging does not appear to impact overall survival.

Purpose: We evaluate the role of fluorodeoxyglucose F 18 positron emission tomography (PET) in patients with renal cell carcinoma (RCC) by retrospective review. To our knowledge this series is the largest reviewing the use of PET in patients with RCC., Materials and Methods: A total of 66 patients who underwent 90 PET scans for suspected or known RCC were identified. Dictated reports of PET, chest computerized tomography (CT), abdominal/pelvic CT and bone scan were examined with confirmation of results by histopathology or followup of at least 1 year. The accuracies of PET and conventional imaging modalities were compared., Results: PET exhibited a sensitivity of 60% and specificity of 100% for primary RCC tumors (abdominal CT demonstrated 91.7% sensitivity and 100% specificity). For retroperitoneal lymph node metastases and/or renal bed recurrence, PET was 75.0% sensitive and 100.0% specific (92.6% sensitivity and 98.1% specificity for abdominal CT). PET had a sensitivity of 75.0% and a specificity of 97.1% for metastases to the lung parenchyma compared to 91.1% and 73.1%, respectively, for chest CT. PET had a sensitivity of 77.3% and specificity of 100.0% for bone metastases, compared to 93.8% and 87.2% for combined CT and bone scan. In 39 scans (32 patients) PET failed to detect RCC lesions identified by conventional imaging., Conclusions: The role of fluorodeoxyglucose F 18 PET in the detection of RCC is limited by low sensitivity. With superior specificity PET may have a complementary role as a problem solving tool in cases that are equivocal on conventional imaging.

Purpose: We evaluated the efficacy of a 3-dimensional (D) navigator for retroperitoneal laparoscopic nephrectomy., Materials and Methods: A total of 21 patients with malignant localized renal (16) or ureteral (5) neoplasms underwent multi-detector row computerized tomography. The 3-D navigator was created using volume rendering technique. These findings were compared with videos obtained during laparoscopy., Results: The 3-D navigator depicted all renal arteries (100% sensitivity) and 24 of the 25 renal veins (96% sensitivity). Hilar anatomy, including the tumor, major vessels and adrenal gland, and their relationships were visualized as in laparoscopic views., Conclusions: The 3-D navigator has a potentially important role in retroperitoneal laparoscopic nephrectomy. It is able to guide surgeons and aid in avoiding operative risks and possible complications.

Purpose: We determine the feasibility and safety of performing percutaneous cryoablation of renal tumors in patients with von Hippel-Lindau disease., Materials and Methods: We selected 2 men and 2 women with von Hippel-Lindau disease and radiographic determined solid renal tumors were selected to undergo percutaneous cryoablation. All patients underwent standard preoperative evaluation. An interventional magnetic resonance imaging unit was used for probe guidance and ice ball monitoring. The cryoablation procedure was performed with a 2 or 3 mm. cryoprobe using a pressurized argon gas system for ice ball formation. The patients were hospitalized overnight for observation and discharged home the following day. A followup computerized tomogram or magnetic resonance imaging scan was performed at 1 week, 1, 3, 6 and 12 months and every 6 months thereafter, along with physical examination, urinalysis, serum blood urea nitrogen and creatinine., Results: A total of 5 tumors were treated ranging from 2.8 to 5.0 cm. in diameter. All patients underwent the procedure without difficulty with 2 requiring re-treatment due to residual tumor for a total of 7 treatments. At followup from 2 to 23 months there has been no radiographic evidence of recurrence at the cryoablated areas., Conclusions: Percutaneous cryoablation of renal tumors in patients with von Hippel-Lindau disease proved to be successful in this initial series. Although 2 patients had residual tumor after the initial cryoablation procedure re-treatment was performed with no adverse sequela. This minimally invasive therapy may allow patients with von Hippel-Lindau disease to avoid the necessity of multiple open surgical procedures.

Purpose: We describe our technique of and single institutional experience with purely laparoscopic partial nephrectomy for renal tumor, wherein the focus is to duplicate established open techniques of oncologic nephron sparing surgery., Materials and Methods: Since August 1999 laparoscopic partial nephrectomy for renal tumor has been performed in 50 patients. Of the patients 24 (48%) had either a compromised contralateral kidney (20) or a solitary kidney (4). Mean tumor size was 3.0 cm. (range 1.4 to 7). In 9 patients (18%) the inner margin of the tumor was in close proximity to the pelvicaliceal system. Our current laparoscopic technique involves preoperative ureteral catheterization, laparoscopic renal ultrasonography, transient atraumatic clamping of the renal artery and vein, tumor excision with an approximate 0.5 cm. margin using cold endoshears and/or J-hook electrocautery, pelvicaliceal suture repair (if necessary) and suture repair of the renal parenchymal defect over surgicel bolsters. In 1 case renal surface hypothermia was achieved laparoscopically with ice slush. All suturing and knot tying were performed with free hand intracorporeal laparoscopic techniques exclusively., Results: All procedures were successfully completed without open conversion. Mean surgical time was 3.0 hours (range, 0.75 to 5.8) and mean blood loss was 270.4 cc (range 40 to 1,500). Mean warm ischemia time was 23 minutes (range, 9.8 to 40). Caliceal entry in 18 cases (36%) was suture repaired in a watertight manner. Following caliceal repair, none of these 18 patients had a postoperative urine leak. Hospital stay averaged 2.2 days (range 1 to 9). Major complications occurred in 3 patients (6%) including intraoperative hemorrhage in 1, delayed hemorrhage necessitating nephrectomy in 1 and urine leak in 1. Renal cell carcinoma was confirmed on pathological examination in 34 patients (68%), and all had negative inked surgical margins for cancer. During a mean followup of 7.2 months (range 1 to 17) no patient has had local or port site recurrence or metastatic disease., Conclusions: Laparoscopic partial nephrectomy is a viable alternative for select patients with a renal tumor. The largest single institutional experience to date is presented wherein the open techniques of nephron sparing surgery have been duplicated laparoscopically.

Purpose: Bone scan is performed as part of the evaluation of bone metastasis. We assessed the diagnostic value of bone scan in patients with renal cell carcinoma., Materials and Methods: Bone scan was performed at presentation in 205 patients with confirmed renal cell carcinoma. Abnormal hot areas were further evaluated by x-ray, computerized tomography or surgery., Results: Of the 56 patients (27%) with an abnormal bone scan 32 (57%) had osseous metastatic lesions. Overall bone metastasis was present in 34 of the 205 patients (17%). Bone scan had 94% sensitivity and 86% specificity. Of the 124 patients with clinically localized, stages T1-2N0M0 disease exclusive of bone metastasis 6 (5%) had bone metastasis only, whereas 28 of 81 (35%) with locally advanced or metastatic disease had bone metastasis, including 12 (35%) who complained of bone pain and 19 (56%) who presented with other symptoms due to local tumor growth or metastasis at other sites. Three patients (9%) were asymptomatic. There was osseous metastasis without other metastasis, enlarged regional lymph nodes or bone pain in 7 patients, including 1 with stage T1b (2% of all with that stage), 2 with stage T2 (5%), 1 with stage T3a (4%), 1 with stage T3b (6%), 1 with stage T3c (14%) and 1 with stage T4 (6%) disease., Conclusions: Bone scan may be omitted in patients with stages T1-3aN0M0 tumors and no bone pain because of the low proportion of missed cases with bone metastasis.