Survival after partial and radical nephrectomy for the treatment of stage T1bN0M0 renal cell carcinoma (RCC) in the USA: a propensity scoring approach

Study Type – Therapy (cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Partial nephrectomy has become the standard of care for T1a renal tumours, and the application of nephron‐sparing techniques has increasingly been expanded to patients with localized T1b cancers. However, the relative efficacy of partial versus radical nephrectomy for these medium‐sized tumours has yet to be definitively established. This study employs a propensity scoring approach within a large US population‐based cohort to determine that no survival differences exist among patients with T1b renal tumours undergoing partial versus radical nephrectomy.

OBJECTIVES

• ? To compare survival after partial nephrectomy (PN) vs radical nephrectomy (RN) among patients with stage TIb renal cell carcinoma (RCC) using a propensity scoring approach.
• ? Propensity score analysis is a statistical methodology that controls for non‐random assignment of patients in observational studies.

PATIENTS AND METHODS

• ? Using the Surveillance, Epidemiology, and End Results registry, 11 256 cases of RCCs of 4–7 cm that underwent PN or RN between 1998 and 2007 were identified.
• ? Propensity score analysis was used to adjust for potential differences in baseline characteristics between patients in the two treatment groups.
• ? Overall survival (OS) and cancer‐specific survival (CSS) of patients undergoing PN vs RN was compared in stratified and adjusted analysis, controlling for propensity scores.

RESULTS

• ? In all, 1047 (9.3%) patients underwent PN. For the entire cohort, no difference in survival was found in patients treated with PN as compared with RN, as shown by the adjusted hazard ratio (HR) for OS (1.10; 95% confidence interval [CI]: 0.91–1.36) and renal‐CSS (HR 0.91; 95% CI: 0.65–1.27).
• ? When the cohort was stratified by tumour size and age, no difference in survival was identified between the groups.

CONCLUSIONS

• ? Even when stratified by tumour size and age, a survival difference between PN and RN in a propensity‐adjusted cohort of patients with T1b RCC could not be confirmed.
• ? If validated in prospective studies, PN may become the preferred treatment for T1b renal tumours in centres experienced with nephron‐sparing surgery.

     

囊性肾癌临床特点及诊治分析

目的：分析囊性肾癌的临床特点,探讨囊性肾癌的诊断及治疗方法。方法回顾性分析12例囊性肾癌患者的临床表现、影像学特征、手术方法、病理特征及随访结果,并结合相关文献就其临床特点进行讨论。结果12例患者术后病理结果透明细胞癌10例,嫌色细胞癌2例。肿瘤直径1．5～8．5cm,平均4．4cm。TNM分期：T1N0M010例,T2N0M02例,其中多房囊性肾癌7例,单房囊性肾癌5例。随访13～78个月,平均39个月,均无复发和转移。结论囊性肾癌早期诊断较为困难,应结合影像学检查、术中冰冻切片及术后病理结果确诊。囊性肾癌恶性度低,预后较好。囊性肾癌同肾癌一样采用肾癌根治术或保留肾单位的手术,保留肾单位的手术为治疗的最佳选择。     

In vitro removal of beta-2-microglobulin from uremic blood with an immunoadsorption wall

Dialysis-related amyloidosis (DRA), caused by the accumulation of beta-2-microglobulin (β-2M), remains a major concern in long-term renal replacement therapies. For years, we have developed an immunoadsorption wall (iWall) for the removal of β-2M. In this study, we employed a new approach taking advantage of the melting of a buffer ice rod to improve the conditions associated with the manufacturing of an iWall and tested its performance with uremic serum and blood. The preliminary results reveal that the present iWalls thus prepared not only possess the superior properties of affinity and specificity but also show structural stability and acceptable hemocompatibility. We believe that this breakthrough might provide a promising path to successful treatment of DRA as well as establish a useful platform for studying removal of certain pathological toxins accumulated in the blood.     

Activation of the tubuloglomerular feedback mechanism in dehydrated rats

To study the influence of the tubuloglomerular feedback control (TGF) on the regulation of glomerular filtration rate (GFR) during dehydration, micropuncture experiments were performed on surface nephrons of dehydrated rats. Dehydration was achieved by withdrawal of food and water for 24 h. The urine flow rate decreased to 1.5 μl/min (controls 2.9 μl/min) and GFR decreased in these rats to 0.80 ml/min (controls 1.22). TGF was studied by two different micropuncture procedures. With the first technique the changes in proximal stop-flow pressure in response to changes of the late proximal microperfusion rate were measured. With this technique the perfusion rate necessary to induce a half maximal stop-flow pressure response, the turning point, was also determined. An increased TGF sensitivity was found in dehydrated rats, as indicated by increased stop-flow pressure responses (35 versus 26%) and decreased turning points (16 versus 21 nl/min). With the second micropuncture technique the single nephron GFR (SNGFR) was measured at distal and proximal tubular sites, in the same nephron. Distal SNGFR was decreased during dehydration to 32.2 nl/min, versus 42.7 nl/min in controls. A significant difference between paired SNGFR measurements in the same nephron was observed during dehydration, the proximal value being 5.3 nl/min higher than the distal, whereas this difference was not seen in control rats. This finding indicates that activation of the feedback mechanism takes place to reduce SNGFR. It is concluded that the decrease in whole kidney GFR is partly caused by the observed increase in feedback activity. The present results are also in agreement with our earlier hypothesis that the hydrostatic and oncotic pressure conditions within the interstitial space surrounding the macula densa cells modulate the sensitivity of the tubuloglomerular feedback mechanism.     

The position of short and long loops of Henle in the rat kidney

Summary To determine the histotopographical relations of short and long loops of Henle in the rat kidney single short and long-looped nephrons were marked by microinjection with a silicone rubber and subsequently traced in histological serial sections. Short loops of Henle, derived from both supericial and midcortical nephrons, follow a similar course and possess similar histotopographical relations. In the medullary rays of the renal cortex and in the outer stripe of the outer medullary zone both limbs of short loops of Henle are lying together, near to the corresponding collecting duct. At the transition of outer and inner stripes the descending limbs turn towards the bundles and descend in the bundle periphery juxtaposed to venous vasa recta. After looping back at the junction of outer and inner zones they change position and ascend distant from the bundles in the vicinity of collecting ducts.The straight proximal portions of long-looped nephrons directly penetrate the outer stripe transversing this zone in tortuous course. In the inner stripe, the thin descending limbs of long loops of Henle descend distant from the bundles among the ascending thick limbs. In the inner medullary zone, neither the descending nor the ascending thin limbs have an exactly defined constant histotopographical position. The long loops ascend straight through the outer medullary zone, usually near to a vascular bundle, and reach the convoluted portion without transversing the medullary rays.The regularity of the histological pattern in the outer medullary zone suggests that the arrangement of the loops may influence their function, whereas in the inner zone the histotopographical position of the loop limbs does not appear to be a functionally important parameter.

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Zusammenfassung Um die histotopographischen Beziehungen von kurzen und langen Henleschen Schleifen in der Rattenniere zu bestimmen, wurden einzelne Nephrone durch Injektion mit einem Kunststoff gekennzeichnet und ihr Verlauf in histologischen Serienschnitten verfolgt.Die kurzen Henleschen Schleifen der Rattenniere gehören zu den oberflächlichen und intermediären Nephronen; sie alle haben einen sehr ähnlichen Verlauf. In den Markstrahlen der Nierenrinde und im Außenstreifen des Nierenmarkes liegen die zusammengehörenden Schenkel einer Schleife nebeneinander und gleichzeitig in der Nähe des zugehörigen Sammelrohres. An der Grenze zum Innenstreifen biegen die absteigenden Schleifenschenkel zu einem Gefäßbündel hin, in dessen Peripherie sie absteigen — eng assoziiert mit aufsteigenden venösen Vasa recta. Am Ende des Innenstreifens biegen sie um; ihre aufsteigenden Schenkel verlaufen in der Nähe von Sammelrohren.Die langen Henleschen Schleifen gehören zu den juxtamedullären Nephronen. Im Gegensatz zu den geraden Anteilen des distalen Tubulus verlaufen die geraden Anteile des proximalen Tubulus der langen Schleifen im Außenstreifen gewunden. Im Innenstreifen verlaufen ihre absteigenden Schleifenschenkel abseits der Gefäßbündel zwischen aufsteigenden Schleifenschenkeln, während ihre aufsteigenden Schenkel häufig in der Nähe eines Gefäßbündels liegen. In der Innenzone haben weder die absteigenden noch die aufsteigenden Schleifenschenkel charakteristische histotopographische Beziehungen.Die strenge Ordnung der Strukturen im Innenstreifen der Rattenniere läßt vermuten, daß hier die Lagebeziehungen der Henleschen Schleifen für ihre Funktion von Bedeutung sind, während in der Innenzone die genaue Zuordnung der Schleifenschenkel zu anderen Strukturen für funktionell wenig bedutend erachtet wird.

     

切缘大小对早期肾癌保肾手术远期临床效果的影响

 目的比较不同切缘保肾手术患者远期临床效果,探讨小切缘保肾手术治疗早期肾癌的安全性及有效性。方法回顾分析325 例对侧肾脏正常T1a期肾癌保肾手术,依切缘大小分为≤5 mm 组125 例,5~10 mm组102 例及跃10 mm组98 例。病理评估切缘状态并随访远期疗效。结果全部病例切缘病理均阴性,3 组切缘大小平均为,≤5 mm 组2.2 mm,5~10 mm 组6.7mm,>10 mm组11.8 mm,差异有统计学意义（ P<0.05）。平均随访79 个月（15~132 个月）,≤5 mm 组1 例出现同侧肾脏异位复发（0.74%）,5~10 mm组1 例出现原位局部复发（0.98%）,2 者经肾癌根治术治愈并存活至今。>10 mm 组无局部复发（0%）。各组复发率差异无统计学意义（跃0.05）。3 组患者均无远处转移及癌特异性死亡发生。Kaplan-Meier 生存分析5年总体生存率为≤5 mm 组99.2%,5~10 mm组99.0%,跃10 mm 组98.0%（ P>0.05）。结论不同切缘大小保肾手术远期临床效果相当,而小切缘保肾手术难度降低,并发症减少,且有利于保留更多的功能性肾单位,是早期肾癌有效的治疗手段。     

Three-dimensional architecture of nephrons in the normal and cystic kidney

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Outcomes according to treatment using an established protocol in patients with bilateral Wilms' tumor: A national Canadian population-based study

BackgroundBilateral Wilms tumor (BWT) is a rare entity. The goal of this study is to report outcomes (overall and event-free survival, OS/EFS) of BWT in a large cohort representative of the Canadian population since 2000. We focused on the occurrence of late events (relapse or death beyond 18 months), as well as outcomes of patients treated following the only protocol specifically designed for BWT to date, AREN0534, compared to patients treated following other therapeutic schemes.MethodsData was obtained for patients diagnosed with BWT between 2001 and 2018 from the Cancer in Young People in Canada (CYP-C) database. Demographics, treatment protocols, and dates for events were collected. Specifically, we examined outcomes of patients treated according to the Children's Oncology Group (COG) protocol AREN0534 since 2009. Survival analysis was performed.Results57/816 (7%) of patients with Wilms tumor had BWT during the study period. Median age at diagnosis was 2.74 years (IQR 1.37–4.48) and 35 (64%) were female; 8/57 (15%) had metastatic disease. After a median follow-up of 4.8 years (IQR 2.8–5.7 years, range 0.2–18 years), OS and EFS were 86% (CI 73–93%) and 80% (CI 66–89%), respectively. Less than 5 events were recorded after 18 months from diagnosis. Since 2009, patients treated according to the AREN0534 protocol had a statistically significant higher OS compared to patients treated with other protocols.ConclusionsIn this large Canadian cohort of patients with BWT, OS and EFS compared favorably to the published literature. Late events were rare. Patients treated according to a disease-specific protocol (AREN0534) had improved overall survival.Type of studyOriginal article.Level of evidenceLevel IV.     

A method for the organ explant culture of fish kidney tubules

Summary A method for long-term organ explant culture of isolated fish kidney tubules from two teleost species is provided. Tubules maintained normal structures for 8 weeks when cultured in supplemented CMRL-1066 medium in controlled atmosphere chambers.