Effect Of Partial Nephrectomy Research Articles

Can remote ischemic preconditioning counteract the renal functional deterioration attributable to partial nephrectomy under warm ischemia? Results of an animal study

BackgroundTo investigate if remote ischemic preconditioning (RIPC) can offer any renoprotective value by counteracting the deleterious effect of partial nephrectomy (PN) under warm ischemia on renal function.MethodsFour groups, each with 5 Wistar albino rats, were constructed; RIPC + PN, PN, RIPC and sham. Right nephrectomy was performed to constitute a solitary kidney model. RIPC denoted sequential clamping/declamping of the femoral artery/vein complex. PN was performed under warm-ischemia following RIPC. Blood samples were collected on multiple occasions until euthanasia on day 7.Immunoassays were conducted to measure the serum and tissues levels of kidney injury markers. Kidneys were examined histologically and morphometric analyzes were performed using digital scanning.ResultsIL-33 levels did not differ significantly between the groups. Serum levels of KIM-1, NGAL, and aldose reductase in RIPC + PN, PN and RIPC groups were significantly lower than that of sham group. Tissue biomarker levels were similar across groups.The observed trend in mean necrosis area of PN group was higher than that of RIPC + PN group (p > 0.05). The transitional zone between necrosis and healthy tissue showed a trend towards increasing width in the rats subjected to RIPC before PN vs. those who underwent PN without RIPC (p > 0.05).ConclusionRIPC failed to counteract the renal functional consequences of PN under warm ischemia in a solitary kidney animal model. The supportive but marginal histological findings in favor of RIPC’s renoprotective potential were not supplemented with the changes in serum and tissue biomarker levels.

Effect of partial nephrectomy with positive margin on recurrence and metastasis in patients with renal cancer: a Meta-analysis

Objective Systematic assessment of the effect of positive margin on recurrence and metastasis in patients with renal cell carcinoma who underwent partial nephrectomy. Methods The literature were searched on the rate of recurrence and metastasis in patients with positive margin and partial nephrectomy published in PubMed, Embase, Cochrane, China Biomedical Literature Database, China Knowledge Network, VIP Chinese Science and Technology Journal Database, and Wanfang Chinese Database up to December 2018. The quality of the literature included in this study was evaluated by two reviewers, and a meta-analysis was performed on the literature that met the inclusion criteria using the Revman 5.0 statistical software provided by Cochrane Collaboration. Results A total of seven articles were included, six of which were case-control studies, and the other one was a cohort study. These seven articles consisted of 6 928 patients, including 407 positive margins and 6 521 negative margins. For recurrence and metastasis, 407 positive margins were composed of 25 recurrences and 21 distant metastases, while 6 521 negative margins consisted of 68 recurrence and 96 distant metastasis. The disease-free survival rate of patients with positive margins is lower than that with negative margins (OR=4.92, 95%CI 2.66-9.08, P<0.001). The results of subgroup analysis of patients with recurrence and metastasis based on positive margin exhibited that positive margin increased the risk of recurrence in patients undergoing partial nephrectomy (OR=5.05, 95%CI 2.06-12.37, P<0.001), as well as the risk of metastasis (OR=3.70, 95%CI 2.18-6.26, P<0.001). Since different studies consisted of patients with different tumor staging, a stratified analysis was conducted and the disease-free survival rate of patients with positive margins decreased compared with that of negative margins (OR=4.13, 95%CI 2.54-6.70, P<0.001), although there were differences in the staging of tumor patients included in different studies, which did not weaken the results. Conclusions Positive margins increase the risk of recurrence and metastasis in patients undergoing partial nephrectomy. Key words: Kidney neoplasms; Partial nephrectomy; Positive margin; Recurrence; Metastasis; Meta-analysis

Functional and oncologic outcomes after partial nephrectomy in anatomical solitary kidney

Objective To investigate the effect of partial nephrectomy of anatomical solitary kidney on tumor control and renal function preservation. Methods 10 patients with anatomical solitary kidney underwent partial nephrectomy from December 2007 to May 2016, including 6 males and 4 females ranged from 38 to 71 years old with an average of 57 years old. The PADUA score ranged from 6-10, with an average of 7.6. The tumor diameter ranged from 1.0 to 7.4 cm, with an average of 3.2cm. Results 7 cases underwent laparoscopic surgery. 3 cases underwent open surgery. Mean operation time was 168min (ranged 103-217min). Mean blood loss was 135ml (ranged 20-400ml). The renal arteries were blocked in all patients. The ischemia time ranged from 9 to 33min, with an average of 20.6min. The mean estimated glomerular filtration rate at one week after surgery [40.7ml/(min·1.73 m2)] decreased 44.7% compared with pre-operation [73.6 ml/(min·1.73 m2)]. Acute kidney injury developed in 2 patients. One required temporary dialysis. The other improved after conservative treatment. There were no other complications such as urinary fistula and hemorrhage. The pathology analysis confirmed that 2 cases were angiomyolipoma, one case was benign cyst, 6 cases were renal clear cell carcinoma, and one case was multilocular cystic renal cell carcinoma. 4 cases were stage pT1a, one case was stage pT1b, one case was stage pT2a, and one case was stage pT4. Positive margin was found in one case. The average follow-up period was 28.2 months(ranged 3-58months). Only one patient need long-term dialysis 20 months after surgery at the latest follow up. Another patient had local recurrence and ipsilateral adrenal metastasis. Conclusions Satisfactory effect of tumor control and renal function preservation can be achieved by partial nephrectomy in solitary kidney, which prevent or delay the occurrence of hemodialysis effectively. Key words: Solitary kidney; Kidney neoplasms; Partial nephrectomy

Effects of Partial Nephrectomy on Postoperative Blood Pressure

PurposeThe effects of partial nephrectomy (PN) on postoperative blood pressure (BP) are not known, and PN has the potential to worsen BP. We therefore sought to determine whether PN alters postoperative BP.Materials and MethodsPatients who underwent PN for suspected malignancy at our institution from 2002 to 2008 were included. Data on BP and medication from before and after PN were retrieved from family physicians. BP and number of antihypertensive medications were compared after surgery with preoperative values by use of paired t tests and Chi-squared analyses, respectively.ResultsOf 74 patients undergoing PN and providing consent, 48 met the inclusion and exclusion criteria, with a median follow-up of 24 months. For the early postoperative period (1 month to 1 year after surgery), the mean BPs (132.3/77.0 mmHg) were unchanged compared with preoperative values (132.4/78.0 mmHg; p=0.59 systolic BP and p=0.30 diastolic BP). For the later postoperative period (beyond 1 year after surgery), the mean postoperative systolic BP was unchanged from the mean preoperative systolic BP (131.2 mmHg vs. 132.4 mmHg, respectively; p>0.30). However, the corresponding average diastolic BP was lower in the long term (78.0 mmHg versus 76.4 mmHg respectively; p=0.01). No significant difference in the mean number of BP medications prescribed preoperatively, at one year, and beyond one year was identified (p>0.37).ConclusionsPN does not result in initial or long-term postoperative deterioration in BP.

Effects of Prolonged Warm and Cold Ischemia in a Solitary Kidney Animal Model after Partial Nephrectomy: An Ultrastructural Investigation

Ischemia–reperfusion injury can be detrimental to the solitary kidney, especially when it is accompanied by ablation. To the authors’ knowledge, the effects of partial nephrectomy with prolonged application of ischemia have never been described at the ultrastructural level. Therefore, the authors used an animal model and focused on putative structural effects in the glomerular basement membrane and the podocytes. They demonstrate the advantageous role of cold ischemia, even in up to 120 min. In contrast, more than 60 min of warm ischemia leads to catastrophic lesions in all the cellular structures, as is reflected by mortality due to acute renal failure.

Determining the best warm ischemic time for patients undergoing partial nephrectomy for renal cancer

The experimental animal study on warm ischemia time (WIT) by Sabbagh and colleagues presents provocative and intriguing results.1 The strength of this study is the use of histologic outcomes as an endpoint for WIT. Using unilateral laparoscopic or open renal artery clamping for various time durations in a porcine model, the authors suggested that no permanent renal histopathologic damage occurred with up to 60 minutes of WIT in the clamped kidney. In addition, they demonstrated that up to 3 hours of pneumoperitoneum caused no histopathologic changes in the non-clamped, contralateral kidney 14 days after surgery. Should we extrapolate these results to humans and be comfortable with WITs of up to 60 minutes in patients undergoing partial nephrectomy for renal cancer? Though the results of this study are attractive, they should be interpreted with caution for several reasons.2 Firstly, physiologic differences are noted between humans and animals, such as unique thrombinolysis kinetics in pigs, that could contribute to disparate WIT outcomes.3 Furthermore, although others have shown that there is little effect on early postoperative renal indicies with up to 90 minutes of WIT in pigs,3 studies examining the effects of WIT beyond 30 minutes in humans are conflicting.4 With regard to the reversible nature of the multifocal interstitial nephritis noted in all kidneys clamped for 5 to 60 minutes, the severity of nephritis was not quantified and the number of animals was low. Moreover, examination of renal tissue on postoperative day 14 may not reflect the true long-term histopathologic consequences of renal ischemia that may surface several months or years after surgery. Without quantitative and long term data, conclusions on whether clamping up to 60 minutes is safe based on early hisptopathology are limited. As pointed out by the authors, renal artery clamping was performed without partial nephrectomy such that the effects of partial nephrectomy on WIT histopathologic outcomes could not be determined.1 The trauma of partial nephrectomy, the worse preoperative renal function in renal cancer patients and the comorbid diseases that commonly coincide with renal cancers could also affect WIT outcomes in the non-experimental setting.5 Lastly, longer duration of renal artery clamping (60 minutes) may cause renal artery scaring and stenosis that may not surface for months and could potentially manifest as hypertensive nephropathy years later. Most of the unanswered questions regarding WIT are not easily controlled for in either experimental or clinical studies. Nonetheless, the results of this study are valuable and hypothesis-generating, but the translation to clinical practice will require human studies. Despite the lines of evidence promoting the safety of WITs beyond 30 minutes, logic dictates that renal artery clamp times should be minimized and balanced with safe tumour extirpation.

Effects of partial nephrectomy on the expression of osmolyte transporters

Na+/myo-inositol cotransporter (SMIT) and Na+/Cl-/betaine-gamma-amino-n-butyric acid transporter (BGT-1) are the major osmolyte transporters that are regulated by extracellular osmolarity. We have recently shown localization and rapid regulation of the mRNAs for these transporters in rat kidney. In the present study, we examined the expression of SMIT and BGT-1 in partial nephrectomized rats in order to assess the change in local osmolarity following reduction of renal mass. Four weeks after 5/6 nephrectomy (NX), the rats were compared to sham-operated control animals (CONT). Northern analysis using RNA of whole kidney indicated that there were little differences in the levels of SMIT and BGT-1 mRNAs between the two groups. In situ hybridization revealed that signals for both transporter mRNAs were markedly reduced in the inner medulla of the remnant kidney. In contrast, these signals in the outer medulla increased following nephrectomy. SMIT signals in the cortex increased as well. Grain density, determined by counting grain number per cell, revealed that the signals in the inner medullary collecting ducts were markedly reduced whereas those in the thick ascending limbs of Henle (TAL) as well as macula densa cells were significantly increased. The signals in the TAL and macula densa were reduced by furosemide administration. The increased expression in NX rats may reflect the increased NaCl transport and high local osmolarity in this segment.

The effect of papillectomy on renal function in the rat during hydropenia and after an acute saline load.

The effect of unilateral papillectomy on renal function in the rat was compared with the effect of partial nephrectomy which produced a similar decrease in glomerular filtration rate (G.F.R.) in the presence of an intact papilla. Under hydropenic conditions the kidney with papillectomy had a higher urine flow rate, sodium excretion rate, fractional sodium excretion, and osmolar clearance, while urine osmolality was lower. After an acute saline load the differences in sodium and water excretion disappeared, and fractional excretion of sodium and water were significantly higher in both types of kidney damage than in the contralateral control kidney. Free water reabsorption was lower in the papillectomized kidney after saline loading. Thus removal of the papilla resulted in abnormalities in the renal handling of salt and water which varied with the state of hydration of the animal and which were distinct from the effects of a reduction in G.F.R. by partial nephrectomy. It was concluded that the site of nephron loss, whether mainly in the renal medulla or in the cortex, may be another factor, in addition to G.F.R. and tubular reabsorption, which influences sodium and water excretion by the moderately damaged kidney.

The effects of partial nephrectomy on the blood pressure and renal function of hypertensive dogs

<h2>Summary</h2> A group of 14 dogs that had undergone contralateral nephrectomy was subjected to partial nephrectomy six weeks or more after the onset of hypertension resulting from constriction of the renal artery. None of the dogs was relieved of hypertension after the first partial nephrectomy, but the blood pressure of one of five dogs subjected to a second partial nephrectomy did return to a normal level. All of the dogs had considerable functional renal reserve and there was a demonstrable increase in renal mass after the partial nephrectomies. The dogs tolerated removal of almost 40 per cent of the solitary kidney before persistent elevation of blood urea occurred. One dog survived heminephrectomy. Radioisotope renograms and Hippuran clearances were unaffected either by constriction of the renal artery or by partial nephrectomy. The histologic appearance of specimens of kidney was normal except in one instance in which focal pyelonephritis was found. The dog from which this specimen was removed did not survive partial nephrectomy. This study indicates that, in dogs, prolonged hypertension of renal origin is not relieved by partial nephrectomy. Our data do not seem to corroborate the theory of Braun-Menéndez^3–5that hypertension of renal origin is caused by failure of the kidney to neutralize a renotrophin.