Role of preoperative platelet level in clinical and pathological outcomes after surgery for renal cortical malignancies.

OBJECTIVE •To investigate preoperative platelet level (PLT) as a prognostic factor for pathologic and clinical outcomes following surgery for renal cortical malignancy. PATIENTS AND METHODS • 1422 patients underwent radical or partial nephrectomy at our institution from 1988-2009 for renal cortical lesions. • The cohort with available PLT values was divided into group 1 (PLT ≤ 400 × 109) and (PLT > 400 × 109) based on institutional laboratory upper threshold (400 × 109 cells/liter). RESULTS • 961 patients were divided into groups 1 (n = 870) and 2 (n = 91), with mean age at surgery of 61 and 60 years, 70.6% and 50.6% males (P ≤ 0.0001), 56% undergoing radical nephrectomy in each group, 39.1% vs. 22% undergoing partial nephrectomy (P = 0.001) respectively. • Groups differed significantly inmedian tumour size (5.06 vs. 7.28 cm) (P ≤ 0.001), pathologic T stage (P = 0.002), and metastases (P ≤ 0.0001). No significant difference existed regarding histologic findings at surgery. • With median follow-up of 24 months, PLT > 400 × 109 cells/liter was associated with decreased overall (OS) and disease-specific survival (DSS) using log rank test (P ≤ 0.0001). • On multivariate analysis, controlling for TNM stage, histology, and tumour diameter, PLT > 400 × 109 cells/liter independently predicted decreased OS (HR 1.67, P = 0.007) and DSS (HR 2.39, P = 0.001). As a continuous variable, PLT predicted OS (HR 1.002, P = 0.005) and DSS (HR 1.003, P = 0.004). • With metastatic patients excluded, PLT was significantly associated with OS and DSS, but was not an independent predictor. CONCLUSION • PLT is a clinically significant independent predictor of OS and DSS in continuous and categorical analyses in patients undergoing renal cortical malignancy surgery. PLT may be clinically useful for risk stratifying patients undergoing surgery for renal cancer, especially for prognosis assessment of patients with renal cortical malignancy and micrometastatic disease at surgery.

Autoregulation of islet graft blood flow follows the implantation.

BACKGROUND: Transplantation of pancreatic islets necessitates a revascularization, which is associated with a generalized graft vascular dysfunction, manifested, e.g., as a capillary hypertension, a decreased graft blood perfusion and graft hypoxia. Some of these changes can be due to impaired autoregulation of the newly formed vasculature in the islet grafts, and the aim of the present study was to further examine if this was the case. MATERIALS AND METHODS: We implanted 250 syngeneic islets under the renal capsule of rats and studied them 1 or 12-13 mo later. The blood perfusion of the whole kidney, renal cortex, and islet grafts were recorded in anesthetized animals with an ultrasound probe or laser-Doppler probes, respectively. The blood pressure in the kidneys was then gradually decreased by an adjustable clamp, during simultaneous measurement of blood flow values. RESULTS: The whole kidney, renal cortex, and islet grafts regulated their blood flow in concert with one another down to pressures of approximately 60 mmHg both 1 and 12-13 mo after implantation. However, the variability was greater at 1 mo. CONCLUSION: Islets transplanted under the renal capsule show similar autoregulatory properties with the kidney. It may be that the autoregulatory capacity of the renal interlobular arteries provides the underlying mechanism. This may be of importance for the good long-term survival of transplanted islets at this implantation site in experimental studies.

Comparison of two core biopsy techniques before and after laparoscopic cryoablation of small renal cortical neoplasms.

INTRODUCTION: Cryoablation is an acceptable treatment option for small renal cortical neoplasms (RCN). Unlike extirpative interventions, intraoperative needle biopsy is the only pathologic data for ablated tumors. It is imperative that sampled tissue accurately captures pathology. We studied the optimal intraoperative needle core biopsy protocol for small RCN during laparoscopic renal cryoablation (LCA). METHODS: Patients with RCN<4cm underwent intraoperative biopsy during LCA. Four biopsy cores were taken per tumor, 2 before and 2 after LCA by using both a standard and modified technique. Standard technique: needle biopsy device was deployed after insertion into the renal tissue at a depth of 5mm. Modified technique: needle biopsy device was deployed 1mm outside of the renal tissue. Biopsies were examined and compared with reference standard pathology. Percentage agreement was calculated across biopsy types (standard vs. modified) and time points (pre- vs. postcryoablation). Logistic regression was used to identify factors impacting biopsy accuracy. RESULTS: Thirty patients with 33 RCNs underwent LCA. The mean patient age was 69.1±8.0yrs, and mean tumor size was 2.3±0.7cm. No significant bleeding resulted from biopsies. A definitive diagnosis was made in 31/33 RCNs (94.0%). Ten tumors (30.3%) were benign, 21 (63.7%) were malignant, and 2 (6.0%) were nondiagnostic. Biopsy length was significantly longer using the standard vs. modified technique with mean lengths of 9.3mm vs. 7.0mm, respectively (P=.02). Highest agreement was seen in preablation biopsies (90.3%). A significant association with agreement was seen for younger age (P=.05) and larger tumor size (P=.02). CONCLUSIONS: Younger age and larger tumor size were associated with improved accuracy. Preoperative sampling resulted in superior accuracy and the standard technique resulted in significantly longer cores. Use of preablation standard biopsy technique may result in the most accurate pathologic diagnosis for patients undergoing cryoablation for small RCNs.

Decreased expression of vitamin K epoxide reductase complex subunit 1 in kidney of patients with calcium oxalate urolithiasis.

Urinary prothrombin fragment 1 (UPTF1) is a potent inhibitor of urinary stone formation. UPTF1 exerts such inhibitory effect by effective γ-carboxylation in which vitamin K epoxide reductase complex subunit 1 (VKORC1), the rate-limiting enzyme, is involved. This study examined the correlation between VKORC1 expression and calcium oxalate urolithiasis. The renal cortex samples were obtained from patients undergoing nephrectomy and then divided into 3 groups: urolithiasis group, control group A [hydronephrosis-without-stone (HWS) group], control group B (normal control group). The localization and expression of VKORC1 in renal tissues were determined by using immunohistochemistry, immunofluorescence microscopy, Western blotting and SYBR Green I real-time reverse-transcription PCR. The rapid amplification of cDNA ends (RACE) were conducted to obtain the 3'- and 5'-untranslated region (UTR) of VKORC1. The results showed that VKORC1 was located in the cytoplasm of renal tubular epithelial cells. The expression of VKORC1 in the urolithiasis group was significantly lower than that in the other two control groups (P<0.05). Moreover, the 3'- and 5'-UTR sequence of the VKORC1 gene was successfully cloned. No insertion or deletion was found in the 3'- and 5'-UTR. However, a 171-bp new base sequence was discovered in the upstream of 5'-UTR end in the urolithiasis group. It was concluded that the decreased expression of VKORC1 may contribute to the development of calcium oxalate urolithiasis in the kidney.

Update on the management of T1 renal cortical tumours.

There are a range of treatment strategies for the management of patients with small incidental renal cortical tumours including active surveillance, radiofrequency ablation, cryotherapy, radical nephrectomy and partial nephrectomy. A large number of such tumours are benign and might therefore be over-treated with radical nephrectomy. There are emergent short-term oncological and clinical outcomes for cryotherapy and radiofrequency ablation, and recent studies have illustrated the benefits of partial nephrectomy for minimizing the risk of progression to chronic kidney disease. The outcomes of these different treatment methods are discussed.

Predicting renal functional outcomes after surgery for renal cortical tumours: a multifactorial analysis.

OBJECTIVE: To examine the functional outcomes after radical (RN) and partial nephrectomy (PN) stratified by variables before and after surgery, using estimated glomerular filtration rate (eGFR), as nephrectomy is the standard treatment for localized renal tumours, but the risk of developing chronic kidney disease (CKD) increases after surgery. PATIENTS AND METHODS: We retrospectively analysed patients treated with PN or RN for renal cancer at one institution from 1988 to 2008. Chronic renal function before and after surgery was measured using the eGFR computed using the Modification of Diet in Renal Disease equation. Four outcomes were measured: (i) presence of new-onset renal insufficiency (eGFR <60 mL/min/1.73m(2)); (ii) the percentage change in eGFR; (iii) the change in CKD stage; and (iv) the presence of CKD upstaging. Regression models were used to determine the effect of surgical procedure (RN vs PN), access technique (open vs laparoscopic) and several preoperative characteristics on functional outcomes. RESULTS: In all, 276 patients met the inclusion criteria (174 RN and 102 PN) of whom 209 had a preoperative eGFR of >60 mL/min/1.73m(2). After >or=3 months from surgery, 108/209 (52%) patients developed new-onset eGFR of <60 mL/min/1.73m(2). On multivariate analysis, preoperative CKD stage (P < 0.001) and procedure (P= 0.001) were both independent predictors of all four functional outcomes measured. Also, hypertension was an independent predictor of CKD upstaging (P= 0.02). Surgical access technique was not an independent predictor of any of the renal functional outcomes measured. CONCLUSION: Patients undergoing renal surgery have a high rate of new-onset CKD afterward. After controlling for preoperative risk factors, patients undergoing RN are at greater risk of a decline in renal function. However, surgical access technique was not a significant predictor for renal impairment.

Activity and expression of vitamin K-dependent gamma-glutamyl carboxylase in patients with calcium oxalate urolithiasis.

OBJECTIVES: To evaluate the correlation between vitamin K-dependent gamma-glutamyl carboxylase (GGCX) and the formation of calcium oxalate urolithiasis (COU). METHODS: Renal cortex samples were obtained from patients undergoing nephrectomy and divided into 3 groups: (1) urolithiasic group (n = 44); (2) hydronephrosis-without-stone group (control group A, n = 6), and (3) normal control group (control group B, n = 21). Immunohistochemical technique was established to study the location of GGCX in renal tissues. The carboxylase activity was detected by the isotope-labeled carboxylatic reaction in vitro. We also quantified GGCX mRNA levels using TaqMan real-time reverse-transcription PCR, and protein was detected by Western blot. RESULTS: GGCX was located in the cytoplasm of renal tubular epithelial cells and the activity of GGCX in the urolithiasic group was significantly decreased compared with that of controls (p < 0.05). GGCX mRNA in the urolithiasic group was lower than that in the normal control group, which was on average 7.86-fold underexpressed in the urolithiasic group compared to the normal control group. Protein expression of GGCX in the urolithiasic group (27.64 +/- 0.29) was weaker than that in the other 2 control groups (control group A 55.22 +/- 0.36, control group B 53.78 +/- 0.33), p < 0.05. CONCLUSIONS: The activity and expression of GGCX are decreased in renal tissues of patients with COU.

[Examination of operative method for renal cortical tumors less than or equal to 4 cm and risk of chronic kidney disease].

We retrospectively studied 63 patients undergoing partial or radical nephrectomy for solitary, renal cortical tumor (< or =4 cm) between 1997 and 2008. Analysis was undertaken, with chronic kidney disease defined as glomerular filtration rate (GFR) lower than 60 ml/min per 1.73 m(2). Multivariable analysis showed that radical nephrectomy remained an independent risk factor for patients developing new onset of GFR lower than 60 ml/min per 1.73 m(2) (hazard ratio 3.158 [95% CI 1.335-7.473]). Radical nephrectomy is a significant risk factor for the development of chronic kidney disease.

Adreno-cortical oncocytoma: a case report.

BACKGROUND: Adrenal oncocytoma is a very rare lesion, non functioning and benignin most cases. Only 46 cases have been reported in the medical literature. AIM: This study aimed to report a new case of adrenal oncocytic tumor with uncertain malignant potential. CASE: A 72 year-old- man, consulted for renal fossa pain. Ultrasonography and omputed tomography scan revealed a large mass in the right adrenal gland with extension to the right kidney. A right adrenalectomy and nephrectomy was performed. The diagnosis of adrenal oncocytoma with malignant potential was confirmed by pathology. Patient had a well recovery and left hospital on the fifth day post operatively. He was followed up for 8 months, no tumor recurrence detected. CONCLUSION: Adreno cortical oncocytoma is a rare tumor. The majority of reported cases had good prognosis.

Omission of Cortical Renorrhaphy During Robotic Partial Nephrectomy: A Vattikuti Collective Quality Initiative Database Analysis.

OBJECTIVES: To analyze the outcomes of patients in whom cortical (outer) renorrhaphy (CR) was omitted during robotic partial nephrectomy (RPN). METHODS: We analyzed 1453 patients undergoing RPN, from 2006 to 2018, within a large multi-institutional database. Patients having surgery for bilateral tumors (n = 73) were excluded. CR and no-CR groups were compared in terms of operative and ischemia time, estimated blood loss (EBL), complications, surgical margins, hospital stay, change in estimated glomerular filtration rate (eGFR), and need of angioembolization. Inverse probability of treatment weighting with Firth correction for center code was performed to account for selection bias. RESULTS: CR was omitted in 120 patients (8.7%); 1260 (91.3%) patients underwent both inner layer and CR. There was no difference in intraoperative complications (7.4% CR; 8.9% no-CR group; P = .6), postoperative major complications (1% and 2.8% in CR and no-CR groups, respectively; P = .2), or median drop in eGFR (7.3 vs 10.4 mL/min/m2). The no-CR group had a higher incidence of minor complications (26.7% vs 5.5% in CR group; P < .001). EBL was 100 mL (IQR 50-200) in both groups (P = .6). Angioembolization was needed in 0.7% patients in CR vs 1.4% in no-CR group (P = .4). Additionally, there was no difference in median operative time (168 vs 162 min; P = .2) or ischemia time (18 vs 17 min; P = .7). CONCLUSION: In selected patients with renal masses, single layer renorrhaphy does not significantly improve operative time, ischemia time, or eGFR after RPN. There is a higher incidence of minor complications, but not major perioperative complications after no-CR technique.

Single-port robotic partial and radical nephrectomies for renal cortical tumors: initial clinical experience.

To describe our institution's initial experience with radical (RN) and partial nephrectomy (PN) using the SP robotic system. The recent FDA approval of the da Vinci® SP robotic platform has led to its use in minimally invasive approaches to urologic malignancies. There are little data on its feasibility and safety after implementation for radical and partial nephrectomy. All patients who underwent PN or RN using the SP system at our institution were reviewed. All PNs were performed off-clamp. Patient demographics, preoperative imaging, operative approaches, and perioperative outcomes were collected and analyzed. Sixteen patients underwent PN (n = 13) or RN (n = 3) utilizing the SP robotic system between January 2019 and June 2019. Average age was 58.6 ± 13.9 and 61.0 ± 1.7 years in each group, respectively. A retroperitoneal approach was performed in 7 (53.8%) PN patients and 1 (33.3%) RN patient. A transperitoneal approach was performed in 6 (46.1%) PNs and 2 (66.7%) RNs. Mean operative time and median estimated blood loss for PN was 176.9 ± 64.0 min and 200 (50-800) ml compared to 176.3 ± 73.8 min and 50 (50-400) ml for RN. There was one operative conversion (7.7%) to an open approach in the PN group. Length of hospital stay postoperatively averaged 1.9 ± 1.3 days and 3.3 ± 1.2 days for patients undergoing partial and radical nephrectomy, respectively. SP partial and radical nephrectomies through transperitoneal and retroperitoneal approaches appear to be feasible surgical techniques in the management of cortical renal masses. Off-clamp PN is also a feasible approach using the SP system. However, further study is needed to establish its safety and use in renal surgery across multiple institutions and larger patient cohorts.

Absolok® versus Hem-o-Lok® clips for renorrhaphy during partial nephrectomy for parenchymal renal tumors.

BACKGROUND: To compare perioperative and functional outcomes associated with renorrhaphy performed with two different types of clips (Absolok® vs. Hem-o-Lok®) in a contemporary series of patients who underwent partial nephrectomy. METHODS: Patients in whom Absolok® clips were used to perform haemostasis at the level of tumor bed or to block the running sutures during sliding-clip renorrhaphy (study group) were compared with a contemporary control group of patients in whom renorrhaphy was performed with Hem-o-Lok® clips. Both groups received the same surgical technique via an open or robot-assisted approach. Inner renorrhaphy was performed with one or more 3-0 (26 mm needle) monofilament running suture(s) preloaded with medium Absolok® clips in the study group, and with medium Hem-o-Lok® clips in the control group. Cortical renorrhaphy was performed using interrupted 2-0 (26 mm needle) polyfilament sutures placed at intervals of 1 cm using the sliding-clip technique with Absolok® clips in the study group and with Hem-o-Lok® clips in the control group. Intraoperative and postoperative outcomes were compared. RESULTS: Absolok® clips were used in 57 patients, while Hem-o-Lok® clips were used in 40 patients. The two groups were comparable for all preoperative patient and tumor characteristics. No differences were observed in terms of operating room time (P=0.29), off-clamp technique rate (P=0.96), warm ischemia time (P=0.19) and estimated blood loss (P=0.18). No difference in the rate of positive surgical margins was detected (P=0.21). Ninety-day complications were observed in 32 (33%) cases. No difference in overall and major postoperative complications were observed between the two groups (P=0.20). Abdominal CT scan performed after 3 months following surgery showed no Absolok® clips in all cases. CONCLUSIONS: Absolok® clips are a valid alternative to Hem-o-Lok® clips to secure blood vessels at the level of tumor bed and to perform a sliding-clip renorrhaphy in patients who underwent open or robot-assisted partial nephrectomy.

Distribution of renal tumor growth rates determined by using serial volumetric CT measurements.

PURPOSE: To retrospectively determine the distribution of growth rates across different sizes and subtypes of renal cortical tumors by assessing tumor volume and maximum tumor diameter at serial volumetric computed tomographic (CT) examinations. MATERIALS AND METHODS: The institutional review board approved this retrospective, HIPAA-compliant study. Fifty-three of 2304 patients (34 men, 19 women; mean age, 67 years +/- 10 [standard deviation; range, 39-88 years) who underwent nephrectomy from 1989 to 2006 did not receive preoperative chemotherapy or radiation therapy and underwent at least two preoperative contrast material-enhanced CT examinations (at least 3 months apart) with identical section thickness that was no more than one-fifth of longitudinal tumor diameter. Tumor volume and maximum diameter were measured on CT scans. Reciprocal of doubling time (DT) (RDT) was calculated. Analysis of variance and Student t tests were performed. RESULTS: Thirty-two clear cell carcinomas, 10 papillary carcinomas, six chromophobe carcinomas, four oncocytomas, and one angiomyolipoma were analyzed. Median tumor size was 2.9 cm (range, 1-12 cm). Seven tumors did not increase in volume. DT ranged from -78476.54 to 18057.43 days (mean, -1230.73 days; median, 590.51 days). [corrected] Growth rate determined by using maximum diameter ranged from -10.8 to 33.2 mm/y (mean, 5.1 mm/y; median, 3.5 mm/y). Faster-growing tumors were more likely to be clear cell carcinomas, those of higher grade had higher growth rates. No significant correlation was found between RDT and tumor initial volume, subtype, or grade. Small renal tumors (

The occurrence of intraoperative complications during partial nephrectomy and their impact on postoperative outcome: results from the RECORd1 project.

BACKGROUND: The aim of this study was to analyze the predictive factors of intraoperative complications in patients submitted to PN and the impact of intraoperative complications on postoperative outcomes. METHODS: Data of 1055 patients who underwent PN for cortical renal masses were recorded from a multicenter prospective observational study (RECORd1 project). RESULTS: Overall, 48 (5%) patients experienced 49 intraoperative complications (four medical, 45 surgical). At multivariable analysis, age (OR=1.02, 95% CI: 1.00-1.08, P=0.03), imperative versus elective surgical indication (OR=2.55, 95% CI: 1.12-5.85, P=0.03), open (OR=5.76, 95% CI: 1.05-9.21, P=0.01) and laparoscopic (OR=2.35, 95% CI: 1.11-4.95, P=0.03) versus robotic approaches resulted independent predictive factors of intraoperative complications. Patients experiencing intraoperative complications had a significantly higher rate of overall postoperative complications (41.6% vs. 17.3%, P<0.0001), surgical postoperative complications (29.2% vs. 12.6%, P<0.0001), Clavien 2 surgical postoperative complications (14.6% vs. 7.2%, P=0.05) and a significantly longer length of stay (8 [6-9] vs. 7 [5-8] days, P<0.0001) than those with an uneventful intraoperative course. CONCLUSIONS: Efforts should be made to minimize the risk of intraoperative complications during PN, and, in that case, patients should be carefully monitored.

The 3-D Volumetric Measurement Including Resected Specimen for Predicting Renal Function AfterRobot-assisted Partial Nephrectomy.

OBJECTIVE: To investigate the relationship between postoperative renal function and resected cortex margin volume calculated by a 3-dimensional reconstruction technique based on the resected specimen, and to determine predictors of renal function after robot-assisted partial nephrectomy. METHODS: A total of 114 patients underwent robot-assisted partial nephrectomy from 2014 to 2018. Patients without a 1 mm slice computed tomography or renal scintigraphy were excluded. We identified the margins of the tumor from each resected specimen with 2 mm margin being added as the ischemic margin. The volume of the renal cortex was calculated automatically using 3-dimensional volume analyzer software. The total margin volume was excluded from the ipsilateral cortex volume to calculate the cortex volume split. Predicted estimated glomerular filtration rate (eGFR) was calculated using the change in cortex volume and then compared with the actual eGFR. RESULTS: Eighty-two patients were included in this retrospective study. Sixty-six patients (80%) were cT1a. A strong correlation was observed between renal scintigraphy split and pre- and postoperative cortex volume split (Pearson correlation coefficient r = 0.9330 and 0.8742, respectively). The predicted eGFR correlated strongly with post 1, 3, 6, and 12 months eGFR (r = 0.8929, 0.9294, 0.9320, and 0.8952, respectively). Preoperative relative renal function and total cortex margin volume were independent risk factors for decreasing postoperative renal function. CONCLUSION: This precise volumetric assessment that includes the resected margin is an alternative to renal scintigraphy for predicting postoperative relative renal function. The healthy cortex margin volume calculated by the reconstruction technique is an independent risk factor of decreasing postoperative renal function.

Pathological tumour diameter predicts risk of conventional subtype in small renal cortical tumours.

OBJECTIVE: To examine whether pathological tumour diameter assists in predicting conventional vs other histological subtypes in renal cortical tumours (RCTs) of

The medical and oncological rationale for partial nephrectomy for the treatment of T1 renal cortical tumors.

This article presents the oncological and medical rationale for partial nephrectomy as the treatment of choice whenever possible for T1 renal tumors. The value of partial nephrectomy in the management of small renal cortical tumors is gaining wider recognition thanks to (1) enhanced understanding of the biology of renal cortical tumors; (2) better knowledge about tumor size and stage migration to small tumors at the time of presentation; (3) studies indicating the oncologic efficacy of kidney-sparing surgery, and (4) increasing awareness of the wide prevalence of chronic kidney disease. The overzealous use of radical nephrectomy for small renal tumors must now be considered detrimental to the long-term health and safety of the patient with a small renal cortical tumor.

Predictors of Complications After Percutaneous Image-Guided Renal Cryoablation for T1a Renal Cortical Neoplasms.

PURPOSE: To determine the incidence and predictors of major complications in patients undergoing percutaneous cryoablation (PCA) for small renal masses. METHODS: We performed a retrospective analysis of patients undergoing PCA from 2005 to 2012. We analyzed demographic, radiographic, and complication data. We defined complications as any deviation from the expected postoperative course. We determined predictors of complications. RESULTS: A total of 190 patients were included in the study. The mean age was 69 years, and 132 (69%) were males. The mean tumor diameter was 2.2 cm (0.8-4.0 cm). The mean number of probes utilized per procedure was 2.3. We observed 16 (8.4%) complications including 14 Clavien grade I, which includes 6 (2%) large renal/retroperitoneal hematomas, 4 (2%) pneumothoraxes, 2 (1%) urinary tract infections, and 2 (1%) atrial fibrillations. There were two (1%) Clavien grade II complications (intestinal perforations). In univariable analysis, larger tumors and more probes were associated with higher risk of complications (all ps < 0.05). In multivariable analysis, larger tumor dimension (odds ratio [OR] = 2.85; 95% confidence interval [CI] = 1.34, 6.05; p = 0.006) was independently associated with major complications. After multivariable adjustments for patient's characteristics such as age, gender, American Society of Anesthesiologists, year of surgery, and histopathology, larger tumor dimension (OR = 2.85; 95%CI = 1.34, 6.05; p = 0.006) and more cryoablation probes (OR = 1.94; 95%CI = 1.36, 2.75; p < 0.001) were independently associated with higher risk of major complications. CONCLUSIONS: In a cohort of patients undergoing PCA for T1a small renal mass, larger tumor dimension and more cryoablation probes were independently associated with higher risk of complication. Although PCA is relatively safe and the major complications are infrequent, careful patient selection is crucial.

Fibromyxoid nephrogenic adenoma protruding in a renal cortical cyst. A rare morphological variant in an outstanding location.

Nephrogenic adenoma (NA) is an unusual, benign lesion of the urinary tract, generally presenting in the bladder and with less frequency in the renal pelvis, urethra or ureter. It consists of tubules, microcysts and papillae lined by a single layer of low cuboidal epithelium without atypia. Recently, a fibromyxoid variant mimicking an infiltrating mucinous adenocarcinoma has been described. We report hereby the case of a 70-year-old female with a fibromixoid NA protruding in a renal cortical cyst. Only one case of NA in a renal cortical cyst has been found in the literature and it was of the classical type. The development of a NA in a renal cortical cyst lends support to the theory that the NA results from proliferation of secondarily implanted exfoliated renal epithelial cells.

Ultrasonographic Evaluation of the Kidney in 5/6 Nephrectomized Rats: Correlation with Biochemical and Histopathological Findings.

AIM: To characterize the kidney alterations associated with renal mass reduction by two-dimensional ultrasound and assess the correlation of the ultrasonographic parameters with the histological and biochemical findings. MATERIALS AND METHODS: Rats were divided into two groups: sham-operated animals (n=13), and animals which underwent renal mass reduction (RMR) through 5/6 nephrectomy (n=14). Renal length, renal thickness, cortical thickness, medullary length and echogenicity of the kidneys were evaluated by ultrasonography at 3 and 6 months after the RMR. RESULTS: Except for the renal length, the renal dimensions at 3 and 6 months were significantly higher in the RMR group when compared to the sham-operated group (p<0.05). Furthermore, the cortical and medullary echogenicity was significantly higher in the RMR group when compared to the sham-operated group (p<0.05). A significant correlation was observed between the plasma creatinine level and the renal length 3 months after RMR (r=-0.612, p=0.045). CONCLUSION: These data support future application of ultrasonography for monitoring the progression of renal damage in chronic studies with the 5/6 nephrectomy model.