术前影像诊断肾癌的肾脏良性病变发生率及预测因素分析

目的:研究在中国患者中术前影像学诊断肾癌行肾脏部分切除手术或根治性肾切除手术的肾脏良性占位病变发生率,并分析其预测因素。方法:回顾性分析从2003年1月～2010年9月共1 531例术前影像学诊断为肾癌并行肾脏部分切除手术或根治性肾切除手术患者的临床资料,多因素回归分析术后病理检查证实为良性患者的临床病理资料。结果:在1 531例患者中,共有81例(5.3%)为良性,其中包括错构瘤52例(3.4%),嗜酸细胞腺瘤12例(0.8%),复杂性囊肿6例(0.3%),其他类型11例(0.7%)。单因素分析显示女性、肿瘤最大径较小、年龄较小、囊性占位病变为临床表现者,病理检查证实为良性的可能性大。多因素回归分析显示,女性(OR,3.13;95%CI,1.95～5.04;P<0.001)、肿瘤最大径较小(OR,0.75;95%CI,0.66～0.85;P<0.001)、年龄较小(OR,0.94;95%CI,0.92～0.96;P<0.001)是良性占位病变的独立预测因素,而囊性占位病变不是显著性预测因素。结论:在中国患者中,术前影像学检查诊断为肾癌术后病理检查证实为良性病变的发生率为5.3%,较国外同类研究明显偏低。良性占位病变中最常见的类型为错构瘤,而欧美同类研究中为嗜酸细胞腺瘤。女性、年龄较小、肿瘤最大径较小是良性占位病变的独立预测因素。     

A preoperative prognostic nomogram for solid enhancing renal tumors 7 cm or less amenable to partial nephrectomy

PURPOSE: Small renal masses are increasing in incidence. Most tumors 7 cm or less are treated with radical or partial nephrectomy but clinicians are increasingly relying on ablative therapies and observation for some small renal masses. We present novel nomograms that predict the likelihood of benign, likely indolent or potentially aggressive pathological findings based only on readily identifiable preoperative factors. MATERIALS AND METHODS: Information on all partial nephrectomies performed at a single institution was collected in an institutional review board approved registry. Using retrospectively collected data on all 862 patients who underwent partial nephrectomy for a single, solid, enhancing, clinical T1 (7 cm or less) tumor between 1999 and 2005 tumors were classified as benign or malignant. Grade 3 clear cell renal cell carcinoma, grade 4 renal cell carcinoma of any type and any renal cell carcinoma with vascular, fat or collecting system invasion were considered potentially aggressive. The likelihood of benign, likely indolent or potentially aggressive pathological findings was modeled using multivariable logistic regression models based on age, gender, radiographic tumor size, symptoms at presentation and smoking history. RESULTS: Of 862 small renal masses 20% were benign and 80% were malignant but only 30% of cancers (24% of small renal masses) were potentially aggressive. All 11 patients with systemic symptoms had cancer. The remaining 851 patients underwent further analysis. Factors that were most strongly associated with the likelihood of benign pathology were age, gender, tumor size and smoking history. A nomogram constructed to predict benign histology proved to be relatively accurate and discriminating (bootstrap corrected concordance index 0.644) and calibrated. Small renal masses in older men and younger women were more likely to be benign. With regard to differentiating indolent from potentially aggressive cancers, only advanced age was independently significant on multivariate analysis (p <0.005). The nomogram for this outcome performed with limited ability (concordance index 0.557). CONCLUSIONS: Clinical factors provide substantial predictive ability to predict benign vs malignant pathology for small renal masses amenable to partial nephrectomy. Although most of these small renal masses are benign or indolent, our ability to predict potentially aggressive cancer in this population remains limited.     

Impact of microwave tissue coagulation during laparoscopic partial nephrectomy on postoperative renal function

Laparoscopic partial nephrectomy for small renal tumors has been performed with increasing frequency over the past few years. We prospectively evaluated preoperative and postoperative differential renal function in patients with functioning contralateral kidneys who underwent laparoscopic partial nephrectomy using a microwave tissue coagulator without hilar clamping. Seven patients (five men and two women) in this prospective protocol underwent laparoscopic partial nephrectomy for exophytic tumors using a microwave tissue coagulator when the tumor was 2 cm or less in diameter. Renal scanning with ⁹⁹technetium-labeled diethylenetetraminepentaacetic-acid scan was performed preoperatively and postoperatively at 7 days and 6 months after surgery in all patients. The mean tumor size and surgical duration were 17.0 ± 2.3 mm and 161.1 ± 20.5 min, respectively. Intraoperative blood loss was 35.6 ± 40.7 ml. The preoperative glomerular filtration rate (GFR) and differential split renal function (SF) in the affected kidney were 45.7 ± 12.8 ml/min and 50.5 ± 3.3%, respectively. On postoperative day 7 and at 6 months, GFR and SF in the affected kidney were 36.2 ± 9.0 and 36.8 ± 10.9 ml/min and 44.3 ± 4.1 and 45.0 ± 5.1%, respectively. No postoperative complications occurred. Laparoscopic nonischemic partial nephrectomy using a microwave tissue coagulator has the advantage of technical ease and adequate hemostasis. However, its indication should be restricted to small exophytic renal tumors due to the expected collateral damage causing renal impairment.     

Similar functional outcomes after partial nephrectomy for clinical T1b and T1a renal cell carcinoma

Objectives: To examine the medium‐term functional outcomes of partial nephrectomy for clinical T1b renal cell carcinoma, and to compare them with those of radical nephrectomy for clinical T1b and with those of partial nephrectomy for clinical T1a tumors. Methods: The participants of this study were patients operated for clinical T1a and clinical T1b tumors operated at Tokyo Women's Medical University, Tokyo, Japan, between January 1979 and June 2011. A total of 67 patients underwent partial nephrectomy for clinical T1b tumor, 195 patients underwent radical nephrectomy for clinical T1b tumors and 324 underwent partial nephrectomy for clinical T1a tumors. The outcomes of these three groups were compared. Results: Partial nephrectomy provided better preservation of residual renal function compared with radical nephrectomy for clinical T1b, and the postoperative estimated glomerular filtration rate was similar in the patients who underwent partial nephrectomy for clinical T1b and those who underwent partial nephrectomy for clinical T1a. Postoperative renal function was steadily maintained after partial nephrectomy during the medium‐term follow up. The probability of freedom from new onset of chronic kidney disease after partial nephrectomy for clinical T1b tumors was significantly higher from that after radical nephrectomy for clinical T1b tumors, and similar to that after partial nephrectomy for clinical T1a tumors. Conclusions: The higher anatomical complexity of clinical T1b tumors is unlikely to provide a significant influence on postoperative renal function after partial nephrectomy, when compared with the clinical T1a tumors. These findings support the beneficial role of partial nephrectomy in the preservation of renal function of clinical T1b renal cell carcinoma patients undergoing surgery.     

Is adrenalectomy a necessary component of radical nephrectomy? UCLA experience with 511 radical nephrectomies

PURPOSE: We determine the incidence and characteristics of adrenal involvement in localized and advanced renal cell carcinoma, and evaluate the role of adrenalectomy as part of radical nephrectomy. MATERIALS AND METHODS: The records of 511 patients undergoing radical nephrectomy with ipsilateral adrenalectomy for renal cell carcinoma at our medical center between 1986 and 1998 were reviewed. Mean patient age was 63.2 years (range 38 to 85), and 78% of the subjects were males and 22% were females. Patients were divided into subgroups of 164 with localized (stage T1-2 tumor, group 1) and 347 with advanced (stage T3-4N01M01, group 2) renal cell carcinoma. Staging of tumors was performed according to the 1997 TNM guidelines. A retrospective review of preoperative computerized tomography (CT) of the abdomen was performed. Radiographic findings were subsequently compared to postoperative histopathological findings to assess the predictive value of tumor characteristics and imaging in determining adrenal metastasis. RESULTS: Of the 511 patients 29 (5.7%) had adrenal involvement. Average size of the adrenal tumor was 3.86 cm. (standard deviation 1.89). Tumor stage correlated with probability of adrenal spread, with T4, T3 and T1-2 tumors accounting for 40%, 7.8% and 0.6% of cases, respectively. Upper pole intrarenal renal cell carcinoma most likely to spread was local extension to the adrenal glands, representing 58.6% of adrenal involvement. In contrast, multifocal, lower pole and mid region renal cell carcinoma tumors metastasized hematogenously, representing 32%, 7% and 4% of adrenal metastasis, respectively. The relationship between intrarenal tumor size (mean 8.9 cm., range 3 to 17) and adrenal involvement (independent of stage) was not statistically significant. Renal vein thrombus involvement was demonstrated in 8 of 12 cases (67%) with left and 2 of 9 (22%) with right adrenal involvement. Preoperative CT demonstrated 99.6% specificity, 99.4% negative predictive value, 89.6% sensitivity and 92.8% positive predictive value for adrenal involvement by renal cell carcinoma. CONCLUSIONS: With a low incidence of 0.6%, adrenal involvement is not likely in patients with localized, early stage renal cell carcinoma and adrenalectomy is unnecessary, particularly when CT is negative. In contrast, the 8.1% incidence of adrenal involvement with advanced renal cell carcinoma supports the need for adrenalectomy. Careful review of preoperative imaging is required to determine the need for adrenalectomy in patients at increased risk with high stage lesions, renal vein thrombus and upper pole or multifocal intrarenal tumors. With a negative predictive value of 99.4%, negative CT should decrease the need for adrenalectomy. In contrast, positive findings are less reliable given the relatively lower positive predictive value of this imaging modality. Although such positive findings may raise suspicion of adrenal involvement, they may not necessarily indicate adrenalectomy given the low incidence, unless renal cell carcinoma with risk factors, such as high stage, upper pole location, multifocality and renal vein thrombus, is present.     

肾部分切除术后肾动脉假性动脉瘤形成的危险因素分析

目的 探讨肾部分切除术后发生肾动脉假性动脉瘤(RAP)的危险因素。 方法 2003年7月至2010年5月,肾细胞癌行肾部分切除术患者464例,术后发生RAP 5例(1.1％)。均为男性,左侧2例,右侧3例。对肾部分切除术的手术方法、RAP的临床表现、影像学特点及治疗进行回顾性分析。肿瘤的解剖学特征按照肾脏测量评分系统进行定量分析。 结果 5例RAP肾脏测量评分总分8 ～ 10分,属中、重度复杂性肿瘤。肿瘤直径3.6 cm,平均2.5 ～5.0 cm(直径评分1 ～2分)。4例呈外生性生长,其中3例≥50％肿瘤体积位于肾实质内（外生部分所占比例评分2分）,1例为完全内生性肿瘤（外生部分所占比例评分3分）。肿瘤与肾集合系统的距离均≤4 mm(距离集合系统或肾窦评分3分)。4例肿瘤跨越肾极线和（或）肾中轴线（位置与极线关系评分3分）,1例位于下极线下方（位置与极线关系评分1分）,但肿瘤靠近肾门。5例术后3 ～23 d,平均12 d,发生肉眼血尿和不同程度贫血,4例伴有背部疼痛,2例有明显低血容量表现,分别输血1000 ml和1800 ml。增强CT和选择性动脉造影检查显示RAP主要来源于肾段动脉分支。4例经超选择性动脉栓塞治愈（3例栓塞1次,1例2次）,1例栓塞治疗失败行患肾切除。随访12 ～30个月,平均21个月,5例肾功能正常,RAP无复发。 结论 肾部分切除术后迟发血尿的患者均应警惕RAP的可能性。肿瘤位置及其与肾段动脉分支的关系可能是发生RAP的危险因素。选择合适病例、仔细缝合血管断面和肾实质可减少RAP的发生。早期选择性动脉栓塞是RAP首选治疗方法。     

Trends in the incidence of benign pathological lesions at partial nephrectomy for presumed renal cell carcinoma in renal masses on preoperative computed tomography imaging: A single institute experience with 290 consecutive patients

Objective: The aim of this study was to determine trends in the incidence of benign lesions in patients undergoing surgery for suspicious renal masses on preoperative computed tomography scan. Methods: The records of 1065 patients who underwent open consecutive partial nephrectomy (PN) or radical nephrectomy (RN) between January 2001 and December 2008 were reviewed. Patients who underwent PN during the periods 2001–2002, 2003–2004, 2005–2006, and 2007–2008 were assigned to groups 1, 2, 3 and 4, respectively. The frequencies of benign and malignant lesions in these groups were assessed according to size and histology subtypes. Results: The ratio of PN to RN was 12.4%, 18.3%, 24.3% and 37.2% in groups 1, 2, 3 and 4, respectively (P < 0.05). The mean size of resected lesions was 2.6 cm (range 0.8–6.2 cm). Of the 290 cases, histopathology revealed benign findings in 52 (17.9%). Benign pathology was found in three of 18 cases (16.7%) in group 1, seven of 36 cases (19.4%) in group 2, 12 of 63 cases (19.0%) in group 3 and 30 of 173 cases (17.3%) in group 4. There was no significant difference in the frequency of benign histology among groups. Conclusion: PN, as opposed to RN, has shown a rising tendency over time. The frequency of benign pathology findings after PN for suspicious renal masses on preoperative computed tomography imaging has not decreased. Proper management should favor nephron‐sparing surgery for renal lesions if such lesions can be removed satisfactorily with PN.     

The impact of tumour location on the histological subtype of renal cortical tumours

OBJECTIVE: To determine whether the location of renal cortical tumours (RCTs) is a possible factor affecting tumour behaviour, by investigating whether exophytic vs a central location is associated with a difference in histological subtype distribution, as recognized prognostic factors for RCTs include size, stage, grade, and histological subtype. PATIENTS AND METHODS: Between 1 January 1996 and 1 June 2003, we evaluated 485 consecutive RCTs in 469 patients who had renal imaging studies and underwent either partial or radical nephrectomy at our institution. A radiologist and a urologist independently reviewed the imaging studies of all patients to determine exophytic vs central location. An exophytic lesion was defined as one that clearly both pushed out the renal contour and did not extend into the collecting system, hilum, or renal sinus. A lesion that did not meet these criteria was defined as a central lesion. Logistic regression analysis was used to determine if either type of lesion had a greater representation of any histological subtype. A two-tailed P < or = 0.05 was considered to indicate significance. RESULTS: Of the 485 RCTs, 171 (35%) were exophytic and 314 (65%) were central, while 308 (64%) were clear cell and 177 (36%) were non-clear cell tumour histology. Of the exophytic lesions, 52.0% were clear cell, while 69.7% of central lesions were clear cell (P < 0.001). Conversely, 71.1% of clear cell tumours were central, while 53.7% of non-clear cell tumours were central (P = 0.003). After controlling for size and stage, tumour location remained associated with histological subtype (P = 0.003). CONCLUSIONS: Exophytic lesions are significantly more likely than central lesions to be non-clear cell tumours, and clear cell tumours are significantly more likely than non-clear cell tumours to be central. As studies indicate that the clear cell histological subtype portends a worse prognosis than the non-clear cell subtype, our results imply that tumour location affects the prognosis in RCTs, with exophytic lesions having a better prognosis than central lesions. This result may have important implications for physicians and patients when planning partial vs radical nephrectomy by either open or minimally invasive techniques.     

肾良性肿瘤和瘤样病变诊治分析(附49例报告)

目的　提高肾良性肿瘤和瘤样病变的诊治水平。　方法　肾良性肿瘤和瘤样病变 4 9例 ,均行B超和CT检查 ,14例行MRI检查 ,分析临床表现、病理和影像学特点。 2 1例术前未能确诊 ,按肾癌行肾切除术 ;2 8例行保留肾单位的肿瘤切除术。　结果　各种病变临床症状无特异性。血管平滑肌脂肪瘤CT和MRI表现含脂肪组织的影像学特点。彩超检测 2例肾动脉瘤和 2例动静脉瘘有特异性表现。其他良性病变无特异性影像学表现。行保肾手术的 2 8例患者随访 1～ 9年无复发 ,肾功能正常。　结论　B超、CT、MRI和彩超等影像学检查对肾良性肿瘤和病变有重要诊断价值。有依据的保留肾单位的肿瘤切除术和术中行冰冻病理检查可减少误诊误治。     

Benign pathological findings in 303 Chinese patients undergoing surgery for presumed localized renal cell carcinoma

Objective: To analyze the incidence of benign lesions in Chinese patients undergoing nephrectomies for renal masses identified as localized renal cell carcinoma (RCC) in preoperative imaging. Methods: Between 1999 and 2007, 303 patients (112 female, 191 male) with presumed localized RCC underwent nephrectomy (234 radical nephrectomies and 69 partial nephrectomies). Preoperative computed tomography images and pathological findings were reviewed and analyzed. Results: Pathological examinations revealed 31 (10.2%) benign lesions in the 303 patients. Among these 31 benign lesions, 15 (5.0%) were angiomyolipomas (AML) and only four (1.3%) were oncocytomas. Significantly, 20 (17.9%) of the 112 female patients had benign lesions compared with 11 (5.8%; P = 0.001) male patients. Benign renal lesions were found in five (25.0%) of the 20 patients with renal masses smaller than 2 cm, 13 (13.0%) of the 100 patients with renal masses 2–4 cm in size and 13 (7.1%) of the 183 patients with renal masses larger than 4 cm. Conclusions: Patients in the present study population show a low incidence of benign renal lesions, approximately half of them being AML. Female patients and patients with renal masses smaller than 4 cm are more likely to have benign renal lesions.     

Application of a standardized anatomical classification in a Chinese partial nephrectomy series

Objective: Preoperative aspects and dimensions used for an anatomical classification is a standardized system to assess the anatomical complexity of renal tumors and its impact on perioperative outcomes of partial nephrectomy. The objective is to apply the preoperative aspects and dimensions used for an anatomical classification in a series of Chinese patients undergoing open or laparoscopic partial nephrectomy. Methods: A total of 195 consecutive renal tumors treated with open partial nephrectomy or laparoscopic partial nephrectomy between June 2008 and May 2011 were included in this analysis. All the preoperative images and clinical records were retrospectively evaluated. Complication rate, warm ischemia time, operation time and degree of blood loss were compared among different risk groups (low risk: preoperative aspects and dimensions used for an anatomical score 6–7; intermediate risk: preoperative aspects and dimensions used for an anatomical score 8–9; high risk: preoperative aspects and dimensions used for an anatomical score ≥10). The original preoperative aspects and dimensions used for an anatomical score system was modified by replacing rim location with hilar vasculature involvement and tested for prediction of overall complications. Results: The median preoperative aspects and dimensions used for an anatomical score was 8. Overall complication rate was 17.9%. Preoperative aspects and dimensions used for an anatomical score was an independent predictor for perioperative complications. Intermediate and high‐risk patients had a four‐ and 37‐fold higher risk of complications respectively (P = 0.012, P < 0.001). Higher preoperative aspects and dimensions used for an anatomical score predicted longer operation time (P = 0.007), warm ischemia time (P < 0.001) and higher degree of blood loss (P = 0.003) in open partial nephrectomy patients. In laparoscopic partial nephrectomy patients, preoperative aspects and dimensions used for an anatomical score was also a predictor for warm ischemia time (P = 0.033); however, it was not significant for operation time and degree of blood loss (P = 0.325, P = 0.302). The modified preoperative aspects and dimensions used for an anatomical score was an independent predictor for overall complications (P < 0.001); however, its superiority could not be verified (P = 0.847). Conclusions: The preoperative aspects and dimensions used for an anatomical classification predicts the risk of overall complications in Chinese patients undergoing nephron‐sparing surgery. Replacing the rim location with hilar vasculature involvement might be a promising modification of this scoring system.     

Long-term follow-up of ureteral stump tumors after nephrectomy for benign renal disease

OBJECTIVE: The occurrence of primary carcinoma of the ureteral stump after nephrectomy is rare. In this study, we evaluated the clinical characteristics of ureteral stump tumors after nephrectomy for benign renal disease. METHODS: During a 16-year period, 318 consecutive patients underwent simple nephrectomy for benign renal disease (216 cases) or for donation (102 cases). Eight of these 318 patients diagnosed as having an ureteral stump tumor were treated by ipsilateral ureterectomy with cuff excision of the bladder. Pathologic findings, tumor stages, and clinical characteristics were analyzed. RESULTS: The eight ureteral stump tumors comprised; 6 transitional cell carcinomas (TCCs) and 2 squamous cell carcinomas (SCCs). The mean interval between nephrectomy and ureteral stump tumor diagnosis was 76.5 months. Six of the 8 patients had pyonephrosis and two renal tuberculosis as original renal diseases. Four of the 6 TCCs were stage T1 and 2 stage T2. There was no concomitant bladder tumor at stump tumor diagnosis. Hematuria was the major presenting symptom in 3 of the 8 patients and 4 patients were diagnosed by follow-up imaging study. Two of the 6 ureteral stump TCC patients developed bladder TCC during follow-up. The 5-year survival rate of patients with ureteral stump tumor was 37.5%. T1G1 TCC was associated with a better survival than T2 or G2 TCC. No ureteral stump tumor occurred in cases of donor nephrectomy. CONCLUSION: This study demonstrate, that long-term closed observation is needed to detect ureteral stump tumor, particularly in patients that have undergo nephrectomy for a long-standing inflammatory renal disease such as pyonephrosis or tuberculosis. Hematuria is a major presenting symptom of ureteral stump tumor. However, a follow-up imaging study is also important for ureteral stump tumor detection. The prognosis is poor in cases developing ureteral stump SCC, bladder tumor recurrence, or a high-grade ureteral tumor.     

Laparoscopic application of radio frequency energy enables in situ renal tumor ablation and partial nephrectomy

PURPOSE: To our knowledge we present the initial series of renal mass in situ laparoscopic radio frequency ablation. We also discuss the indications for and results of subsequent laparoscopic partial nephrectomy. MATERIALS AND METHODS: Laparoscopic radio frequency ablation was performed in 13 patients with a mean age of 59 years (range 18 to 81) and a total of 17 small enhancing renal masses. In 5 patients the tumor was subsequently excised completely, whereas in 7 it was left in situ after treatment. In 1 patient with 5 lesions only the largest lesion was excised, while the other 4 were left in situ. RESULTS: Mean tumor size was 1.96 cm. (range 0.9 to 3.6). Tumors that remained in situ tended to be endophytic and located in the mid pole. Pathological analysis revealed renal cell carcinoma in 10 patients, angiomyolipoma in 2 and oncocytoma in the patient with multiple lesions. None of the 8 patients with renal cell carcinoma who had at least 6 weeks of followup (mean 9.8 months, range 1.5 to 22) had any evidence of persistent tumor enhancement on surveillance computerized tomography or any other evidence of disease progression. There was 1 focal positive margin in a patient who underwent radio frequency ablation and excision of renal cell carcinoma but the patient remained disease-free 1 year after treatment. CONCLUSIONS: Early experience with laparoscopic radio frequency ablation in situ or combined with partial nephrectomy shows that it appears to be a safe method of managing small enhancing renal masses. Radio frequency assisted laparoscopic partial nephrectomy is reserved for easily accessible exophytic tumors, while strict surveillance is required for lesions remaining in situ after ablation. Additional followup is required to assess long-term effectiveness.     

Does the incidence of unexpected malignancy in ‘benign’ rectal neoplasms undergoing trans‐anal endoscopic microsurgery vary according to lesion morphology?

Aim Mucosectomy by trans‐anal endoscopic microsurgery (TEMS) allows safe and effective excision of benign rectal lesions. Preoperative endoscopic, clinical and ultrasonographic assessment aims to select benign lesions whilst avoiding inappropriate mucosectomy in lesions with malignancy. This study examines the relationship between lesion morphology and accurate benign preoperative classification of rectal lesions undergoing TEMS. Method Primary lesions preoperatively assessed as benign were identified from a prospective TEMS database. Operative specimen morphology was independently classified by two blinded investigators, using photographs, into flat‐sessile, exophytic or mixed morphology. The accuracy of the preoperative assessment by rectal ultrasonography was compared with the results of histological examination of the excised specimen (χ² and Fisher’s exact tests). Results Of 167 lesions with adequate data, the morphological classification showed 60 flat‐sessile, 56 mixed morphology and 51 exophytic tumours, of which 5, 7 and 9, respectively, contained unexpected malignancy (P = 0.48). Accurate preoperative assessment of a lesion as benign occurred in 89% of flat‐sessile and mixed morphology (n = 55 and 49, respectively) and in 70% of exophytic lesions (n = 36) (P = 0.01). Only the exophytic group contained patients in whom preoperative endoscopic and ultrasonographic staging could not be confidently made (uTx). Histology demonstrated six of the seven uTx cases to be benign. Conclusion In this study exophytic polyps were less likely to be accurately classified as benign using preoperative ultrasonography/endoscopy when compared with flat‐sessile or mixed morphology polyps.     

Laparoscopic partial nephrectomy: the European experience.

Laparoscopic partial nephrectomy is technically difficult but oncologically effective. The operation should be performed in centers with expertise. Hemostasis can be achieved using bipolar coagulation and fibrin glue-coated cellulose. Further studies will determine whether less invasive alternatives (focused ultrasound, cryotherapy) will meet the high standard of open (or laparoscopic) nephron-sparing surgery for small renal cell carcinoma.CommentaryThe technique of laparoscopic partial nephrectomy for the treatment of renal cell carcinoma (RCC) is in its very early stages. The cumulative experience reported in the literature comprises fewer than 100 cases and these have been confounded by a lack of standardized technique and variable experience. There has been difficulty in reproducing the essential elements of open partial nephrectomy using contemporary laparoscopic instrumentation. In this large multicenter European study, hemostasis was achieved with bipolar coagulation and fibrin-coated cellulose. Notwithstanding that case selection was limited to very small (≤3 cm) peripheral renal tumors, the morbidity of partial nephrectomy in this study was greater than that of open partial nephrectomy for small peripheral tumors.At the Cleveland Clinic, we have recently developed a technique for laparoscopic partial nephrectomy which duplicates established open surgical principles. The key technical steps in this approach include:Since August 1999, this technique has been used to perform laparoscopic partial nephrectomy in 36 patients with small, exophytic renal tumors. Mean tumor size was 2.9 cm (range 1.4–7.0 cm). The operation was successful in all cases without any open conversions. Mean operative time was 2.9 h, warm ischemia time was 20 min and blood loss was 237 ml. Formal calyceal suture repair was performed in 7 patients. Mean hospital stay was 1.7 days. The final pathology revealed renal cell carcinoma in 20 patients and other tumors in the remainder. All margins of resection were negative for tumor.Our initial experience suggests that laparoscopic partial nephrectomy can be performed for small exophytic renal tumors with adherence to established principles and techniques of the open surgical approach and with significant benefits for the patient.Andrew C. Novick, M.D.     

Adrenalectomy: defining its role in the surgical treatment of renal cell carcinoma

OBJECTIVES: With the recent widespread use of modern imaging techniques, the frequency of small low-stage renal cell carcinomas (RCC) has grown considerably, giving rise to more conservative surgical approaches. We evaluated the characteristics of adrenal involvement and the accuracy of computerized tomography (CT) in the diagnosis of RCC, defining the real need for adrenalectomy during surgical treatment. METHODS: The medical records of 201 patients undergoing radical nephrectomy and ipsilateral adrenalectomy for localized or advanced RCC, from 1996 to 2002, were analyzed, retrospectively. We considered 76 with stage T1-2 disease and 125 with T3-4N0-1M0-1 disease. In all cases a blinded review of the preoperative abdominal CT was performed. Histopathology records of the surgical specimens were examined to determine the accuracy of the CT in identifying adrenal involvement by RCC. RESULTS: The overall incidence of adrenal metastasis was 4.4%. The mean renal tumor size in patients with adrenal involvement was 7.8 cm. The tumor stage correlated with a probability of adrenal spread (p < 0.05), with T1-2 tumors accounting for 1.3% of cases only. The adrenal gland was diagnosed as abnormal on preoperative CT in 21 patients (10.4%). CT scan demonstrated 88.8% sensitivity, 92.1% specificity, 99.4% negative predictive value and 34.7% positive predictive value for adrenal involvement by RCC. CONCLUSIONS: Adrenal involvement is not likely in patients with localized early stage RCC and adrenalectomy can be omitted in such cases, particularly when CT is negative. However, in selected patients with large high-risk tumors, radical nephrectomy, including removal of the ipsilateral adrenal gland, should be performed.     

Inflammatory pseudotumors of the kidney: a case report

Inflammatory pseudotumors are uncommon benign tumors of unknown etiology which may develop at several anatomical sites, e.g., the airways and gastrointestinal tissues, soft tissues, the orbit, the spleen, or the lymph nodes. The renal site is extremely rare, and presents the problem of differential diagnosis as the clinical and radiological aspects of this tumor are similar to those of an adenoma or an angiomyolipoma, and suggest the presence of a carcinoma, in particular a cystic renal carcinoma which is also a rare form of tumor. There is therefore a risk that this benign lesion could be misdiagnosed. Due to the good prognosis associated with this type of tumor, in cases where the definitive diagnosis has been established no surgical procedure is necessary. However, the difficulty in making this diagnosis preoperatively means that in general the organ has to be surgically removed so that a histological analysis can be made and the negative or positive findings confirmed. In the present study, the case of an inflammatory pseudotumor of the kidney has been described. In this instance, radical nephrectomy of the left kidney was carried out as the disease was presumed to be renal cell adenocarcinoma. However, the histopathological analysis was negative as regards malignancy, and indicated the presence of an inflammatory pseudotumor. This article raises the question of the problem in establishing a preoperative definitive diagnosis, as a correct diagnosis is often only confirmed following nephrectomy (in cases where the contralateral kidney is healthy).     

肾脏交织状血管瘤的影像学表现：附2例报告并文献复习

目的探讨肾脏交织状血管瘤的临床特点及影像学表现,提高对该病的诊断及治疗水平。方法回顾性分析2例原发于肾脏的交织状血管瘤患者的临床资料,2例患者术前接受CT 或 MRI 检查均诊断为肾脏肿瘤性病变,均接受腹腔镜下根治性肾脏切除术。结果肿块在CT 上呈类圆形,边界尚清,凸向肾窦,增强呈不均匀性延迟强化特点;T2 WI 上呈不均匀的稍高信号,DWI 呈等或稍高信号,PWI 上强化方式与增强 CT 相似,呈向心性充填。术后病检肿块呈灰褐色,与周围组织境界清,无包膜;显微镜下,肿块具有松散的小叶结构,肿瘤细胞无异型性;免疫组化示 CD31(＋)、CD34(＋)。术后患者恢复良好,未出现明显复发或转移迹象。结论交织状血管瘤是肾脏的良性血管瘤性疾病,临床少见,影像学上有一定的特点,但术前诊断困难。此类病变应与肾脏恶性肿瘤,特别是血管肉瘤相鉴别。治疗上以手术治疗为主。     

Laparoscopic nephron-sparing surgery for the small exophytic renal mass.

OBJECTIVES: Nephron-sparing surgery has emerged as the treatment of choice for the incidentally detected small renal mass, especially those less than 4 cm in size. We describe our technique and experience with the laparoscopic excision of these lesions. METHODS: Between June 2001 and October 2003, 20 patients underwent nephron-sparing surgery at our institution. Twenty-one laparoscopic partial nephrectomy procedures were performed. All tumors were detected incidentally by cross-sectional imaging. All patients had a solid renal mass or a complex cystic renal mass of Bosniak category III or greater. All solid tumors were exophytic and less than 4cm in diameter. Both transperitoneal and retroperitoneal approaches were used. Hemostasis was achieved without hilar control in 20 of the 21 cases. RESULTS: Twenty renal units were approached transperitoneally, and 1 retroperitoneally. Mean tumor size was 2.6 cm (range, 1.2 to 4). Mean estimated blood loss was 211 mL (range, 50 to 500), and mean operative time was 165 minutes. Pathology revealed renal cell carcinoma in 14 (70%). No intraoperative complications occurred. Two patients required blood transfusions postoperatively. CONCLUSION: Carefully selected patients with small, exophytic renal masses can safely undergo laparoscopic excision. When achievable, this procedure can be a more logical alternative to ablative techniques for the minimally invasive management of such lesions.     

Ultrasound-guided biopsy of homogenous solid renal masses

OBJECTIVES: We evaluated the reliability of sonographic criteria in selecting solid renal masses for percutaneous fine-needle biopsy. METHODS: In study 1 (intraoperative ultrasound study), we prospectively examined 100 consecutive patients scheduled for partial/radical nephrectomy by using two different high-resolution probes (Philips HDI 5000, CT8-4, L12-5; 4-12MHz). The main tumor was intraoperatively evaluated by B-mode and power Doppler sonography. Morphologic characteristics seen on ultrasound were categorized in (non-)homogenous and (non-)cystic renal masses and were related to findings of pathological examination. Study 1 provided the selection criteria for study 2. In study 2 (percutaneous biopsy study), under local anesthesia and with the use of an 18-G needle, we prospectively performed two to three sonographically guided percutaneous biopsies in 30 consecutive patients whose tumors appeared to be homogenous and noncystic according to the sonograph (convex array 3.5MHz, HDI 5000, C5-2 and Falcon 2101 EXL, B+K Medical). RESULTS: In the ultrasound study, only 16 (22.9%) of the 76 clear-cell carcinomas but all 9 (100%) oncocytoma appeared homogenous and noncystic on high-resolution intraoperative ultrasound. By applying these results to 30 patients of study 2 (18 men, 12 women; aged 63+/-7.7 yr, tumor size 29+/-11.3mm) who met these sonographic criteria on preoperative transabdominal ultrasound, we bioptically diagnosed 8 (26.7%) benign tumors; 25 of 30 (83.3%) patients were accurately diagnosed. Small tumors (<3cm), decreased breathing compliance, and medially located renal lesions seem to negatively influence biopsy results. CONCLUSIONS: Kidney tumors that appear noncystic and homogenous on preoperative ultrasound are more likely to be of benign origin. Ultrasound-guided percutaneous biopsy of these solid renal masses could determine renal tumor patients for whom surveillance might be an option. However, experienced and dedicated histopathologic evaluation remains crucial to observe patients with clearly benign biopsy results. All even slightly questionable biopsy findings require surgical exploration.