Time-Dependent Effects of Cryoablation for Renal Tumor on Overall and Split Renal Function

Purpose

To evaluate the influence of percutaneous cryoablation for renal cell carcinoma on function of the affected kidney.

Improved measurement of the glomerular filtration rate from Tc-99m DTPA scintigraphy in patients following nephrectomy

Objective

We aimed to improve Tc-99m DTPA glomerular filtration rate (GFR) scintigraphy (Gates’ method) in a prospective study using Cr-51 EDTA GFR test as a gold standard.

Methods

Fifty-seven Tc-99m DTPA GFR scintigrams in 45 subjects (male/female?=?33:12, age?=?45.9?±?17.6 years, 14 healthy volunteers and 31 nephrectomised patients) were compared using Cr-51 EDTA GFR tests. Using the %renal uptake of Tc-99m DTPA and Cr-51 EDTA GFR, a revised equation for GFR was established through linear regression analysis.

Results

The revised equation for improved GFR was GFR(mL/min)?=?(%renal uptake?×?11.7773)???0.7354. Gates’ original GFRs (70.1?±?20.5 mL/min/1.73 m²) were significantly lower than Cr-51 EDTA GFRs (97.0?±?31.9 mL/min/1.73 m²; P?<?0.0001), but the improved GFRs (98.0?±?26.3 mL/min/1.73 m²) were not different from (P?=?0.7360) and had a significant correlation with (r?=?0.73, P?<?0.0001) the Cr-51 EDTA GFRs. The revised GFR equation effectively demonstrated perioperative GFR changes in kidneys that were operated on and the contralateral kidneys at 3 and 6 months post-partial nephrectomy (n?=?25).

Conclusions

GFR measurement using Tc-99m DTPA scintigraphy could be significantly improved by a revised equation derived from the comparison with Cr-51 EDTA GFR.

Key Points

? Measurement of glomerular filtration rate is difficult following nephrectomy. ? Measurements can be significantly improved by new renal sctintigraphic methods. ? This helps physicians to measure kidney function of patients following nephrectomy. ? Management of renal tumour patients should become more effective.     

Radiofrequency Ablation of T1a Renal Cell Carcinomas within Renal Transplant Allografts: Oncologic Outcomes and Graft Viability

Purpose

To evaluate oncologic outcomes and graft viability after percutaneous radiofrequency (RF) ablation of renal cell carcinoma (RCC) developing within renal transplant allografts.

Impact of Renal Function Trajectory on Renal Replacement Therapy and Mortality Risk after Renal Artery Revascularization

PurposeTo determine the impact of renal function trajectory, defined as the change in renal function over time before and after renal artery stent placement, on long-term risk for renal replacement therapy (RRT) and mortality.Materials and MethodsEstimated glomerular filtration rates (eGFRs) 6–12 months before renal artery stent placement, at the time of intervention, and 6–12 months after intervention were determined in 398 patients. The effect of eGFR change before and after renal artery stent placement was calculated. Cox proportional-hazards ratio was used to determine the risks for RRT and all-cause mortality.ResultsThe risk for RRT was significantly influenced by eGFR change from the time of intervention to follow-up at 6–12 month after treatment (P = .02). In addition, among patients with a postintervention eGFR ≤ 40 mL/min/1.73 m², for every 1 unit of eGFR increase, there was a significant decrease in RRT and all-cause mortality (P < .001 and P < .001, respectively). Secondary parameters that increased RRT risk included diabetes at the time of intervention (P = .03), increased baseline proteinuria (P < .001), and stage 4 or 5 chronic kidney disease (CKD; P = .01 and P = .003, respectively). Multivariate analysis demonstrated higher all-cause mortality rates among patients with diabetes at the time of intervention (P = .009).ConclusionsPostintervention eGFR trajectory improvement approaching 40 mL/min/1.73 m² was associated with decreased RRT and mortality risk. These findings suggest that patients with advanced CKD and renal artery stenosis may benefit from revascularization regardless of their preinterventional renal function measurement.     

Radiofrequency Ablation,Cryoablation, and Microwave Ablation for T1a Renal Cell Carcinoma: A Comparative Evaluation of Therapeutic and Renal Function Outcomes

PurposeTo compare the therapeutic and renal function outcomes of radiofrequency (RF) ablation, cryoablation, and microwave (MW) ablation for treatment of T1a renal cell carcinoma (RCC).Materials and MethodsA retrospective assessment of 297 patients (mean age 72 years range 24–90 years) with biopsy-proven RCC treated with image-guided percutaneous thermal ablation was performed between October 2006 and December 2016. Mean tumor size was 2.4 cm; mean radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, hilar tumor touching the main renal artery or vein, and location relative to polar lines; Preoperative Aspects and Dimensions Used for an Anatomical; and c-centrality scores were 6.0, 7.0, and 2.8, respectively. Assessments of adverse events, treatment efficacy, and therapeutic outcomes were performed among RF ablation, cryoablation, and MW ablation. The 2-year disease-free, metastatic-free, and cancer-specific survival rates were tabulated. Estimated glomerular filtration rate was used to assess for treatment related changes in renal function.ResultsA total of 297 T1aN0M0 biopsy-proven RCCs measuring 1.2–3.9 cm were treated with computed tomography–guided RF ablation (n = 244, 82%), cryoablation (n = 26, 9%), and MW ablation (n = 27, 9%). There were no significant differences in patient demographics among the 3 groups (P = .09). Technical success rates were similar among the 3 treatments (P = .33). Primary efficacy at 1 month postablation was more likely to be achieved with RF ablation and MW ablation than with cryoablation. At 2 years’ follow-up, there was no local recurrence, metastatic progression, or RCC-related death observed in the 3 groups. There was no significant change in estimated glomerular filtration rate among the 3 ablation groups compared with baseline at 2-year follow-up (P = .71).ConclusionRF ablation, cryoablation, and MW ablation are equivalent at 2 years for treatment of T1a RCC for therapeutic outcome, stability of renal function, and low adverse event rate.     

Complications following 573 percutaneous renal radiofrequency and cryoablation procedures

PurposeTo review complications related to percutaneous renal tumor ablation.Materials and MethodsProspectively collected data related to renal radiofrequency (RF) ablation and cryoablation procedures performed from May 2000 through November 2010 were reviewed. This included 573 renal ablation procedures performed in 533 patients to treat 633 tumors. A total of 254 RF ablation and 311 cryoablation procedures were performed; eight patients underwent simultaneous RF ablation and cryoablation. The mean age of patients at the time of the procedure was 70 years (range, 24–93 y), and 382 of 573 procedures (67%) were performed in male patients. Complications were recorded according to the Clavien–Dindo classification scheme. Duration of hospitalization was also documented.ResultsOf the 573 procedures, 63 produced complications (11.0% overall complication rate). There were 66 reported complications, of which 38 (6.6% of total procedures) were Clavien–Dindo grade II–IV major complications; there were no deaths. Major complication rates did not differ statistically (P = .15) between cryoablation (7.7%; 24 of 311) and RF ablation (4.7%; 12 of 254). Of the complications related to cryoablation, bleeding and hematuria were most common. Bleeding during cryoablation was associated with advanced age, increased tumor size, increased number of cryoprobes, and central position (P < .05). Of those treated with RF ablation, nerve and urothelial injury were most common. Mean hospitalization duration was 1 day for RF ablation and cryoablation.ConclusionsComplications related to percutaneous renal ablation are infrequent. Recognition of potential complications and associated risk factors can allow optimization of periprocedural care.     

Risk Assessment of Chronic Kidney Disease following Microwave Ablation for Stage T1 Renal Cell Carcinoma

Purpose

To assess safety and renal-function outcomes after microwave (MW) ablation of localized stage T1 renal cell carcinoma (RCC).

不同肾小球滤过率检测方法在多囊肾肾功能评价中的临床价值

目的探讨99Tcm-二亚乙基三胺五乙酸（99Tcm-DTPA）肾动态显像Gate's法及血肌酐估测法在多囊肾各时期肾小球滤过率（GFR）检测中的应用价值。方法选择2006年1月至2018年9月未行透析治疗的多囊肾患者59例。参考美国慢性肾脏病及透析的临床实践指南,依据慢性肾病（CKD）分期（1~5期）,以双血浆法测定GFR为参考标准,将多囊肾患者分为3组。A组:GFR ≥ 60 mL/（min·1.73m2）,CKD分期为1~2期,共19例;B组:60 mL/（min·1.73 m2）>GFR ≥ 30 mL/（min·1.73 m2）,CKD分期为3期,共23例;C组:GFR < 30 mL/（min·1.73 m2）,CKD分期为4~5期,共17例。将Gate's法、血肌酐估测法测定的GFR分别与双血浆法测定的结果进行配对t检验和Pearson相关分析。结果（1）血肌酐估测法测得的A、B、C 3组的GFR分别为（85.43±19.77）、（46.56±15.48）、（20.96±11.3）mL/（min·1.73 m2）,双血浆法测得的GFR分别为（80.58±16.2）、（42.66±7.63）、（18.61±7.21）mL/（min·1.73 m2）,两者间的差异均无统计学意义（t=-1.462、-1.592、-1.791,均P>0.05）,且均有很好的相关性（r=0.69、0.68、0.92,均P < 0.05）。（2）Gate's法测得的A、B、C 3组的GFR分别为（75.39±20.75）、（42.86±18.95）、（25.85±14.91）mL/（min·1.73 m2）,与双血浆法测定的GFR比较,两者在A、B组中的差异均无统计学意义（t=1.255、-0.061,均P>0.05）,且均有很好的相关性（r=0.55、0.62,均P < 0.05）;但是,两者在C组中的差异有统计学意义（t=-2.132,P < 0.05）,且无明显相关性（r=0.36,P>0.05）。结论Gate's法可很好地评估多囊肾CKD分期为1~3期的患者的肾功能GFR,但对CKD分期为4~5期的患者不适合。血肌酐估测法可有效评价多囊肾CKD各时期的肾功能GFR。     

Microwave ablation of cT1a renal cell carcinoma: oncologic and functional outcomes at a single center

PurposePercutaneous ablation is an established alternative to surgical intervention for small renal masses. Radiofrequency and cryoablation have been studied extensively in the literature. To date, series assessing the efficacy and safety of microwave ablation (MWA) are limited. We present a cohort of 110 renal tumors treated with MWA.MethodsA review of the medical record between January 2015 and July 2019 was performed, retrospectively identifying 101 patients (110 tumors). All ablations were performed by a single board-certified urologist/interventional radiologist. Demographic information, intraoperative, postoperative, and follow-up surveillance data were recorded.ResultsMedian (IQR) age was 69.7 years (60.8–77.0); 27 (24%) were female. Median (IQR) BMI was 27.0 (25.1–30.2) and Charleston Comorbidity Index was 5.0 (4.0–6.0). 82 tumors were biopsy-confirmed renal cell carcinoma/oncocytic neoplasms. Median (IQR) tumor size was 2.0 cm (1.5–2.6). Median (IQR) RENAL nephrometry score was 6.0 (5.0–8.0). Technical success was achieved in all patients and all but one patient were discharged on the same day. Median (IQR) eGFR at baseline and 1 year were 71.9 mL/min/1.73 m² (56.5–82) and 63.0 mL/min/1.73 m² (54.0–78.2); the difference was −5.3 (p = 0.12). Two Clavien-Dindo type-I complications, one type-II complication, and one type-III complication were experienced in this cohort. Median radiographic follow-up was 376.5 days with 2 tumors (2.4% of RCC/oncocytic neoplasms) having recurred to date.ConclusionsMWA is a safe and efficacious treatment option for small renal masses with minimal adverse events and low rates of recurrence in this cohort of 101 patients. Continued follow-up is needed to assess long-term outcomes.     

Percutaneous Cryoablation of Renal Cell Carcinoma with Sinus Vein Involvement Based on Preprocedural Imaging

Purpose

To assess feasibility, safety, and oncologic outcomes of cryoablation in treatment of renal cell carcinoma (RCC) with extension into adjacent renal sinus vein.

Percutaneous Computed Tomography–guided Renal Mass Radiofrequency Ablation versus Cryoablation: Doses of Sedation Medication Used

PurposeTo compare the amount of sedation medication administered during radiofrequency (RF) ablation versus cryoablation of small renal masses.Materials and MethodsRecords were retrospectively reviewed in patients who underwent percutaneous computed tomography–guided RF ablation and cryoablation of small renal masses from January 2002 to June 2011 for patient and tumor characteristics, amount of medications used for moderate sedation, and complications. Sedation was performed by giving patients titrated doses of midazolam and fentanyl. Additional medications were given if the desired level of sedation was not achieved.ResultsThere were 116 patients who underwent 136 ablation procedures; 71 patients underwent RF ablation, and 65 patients underwent cryoablation. RF ablation was associated with a significantly higher mean dose of fentanyl (mean dose for RF ablation, 236.43 μg; mean dose for cryoablation, 172.27 μg; P<.001). RF ablation was also associated with a higher mean dose of midazolam (mean dose for RF ablation, 4.5 mg; mean dose for cryoablation, 3.27 mg; P<.001). In the RF ablation group, two patients required additional sedation with droperidol. As a result of oversedation, two patients in the RF ablation cohort required sedation reversal with naloxone and flumazenil. None of the patients who underwent cryoablation required sedation reversal. No other sedation-related complications occurred.ConclusionsCryoablation of small renal masses was performed with less sedation medication than RF ablation. This finding suggests renal cryoablation is less painful than RF ablation; however, prospective studies with validated pain scales are needed to confirm these results.     

Incidencia de nefropatía inducida por contraste tras una tomografía computarizada

Background and aimsThe term contrast-induced nephropathy is used to describe acute deterioration of renal function after the intravenous administration of iodinated contrast material. We aimed to estimate the incidence of contrast-induced nephropathy and to analyze the evolution of different biomarkers of renal function in patients who underwent computed tomography with intravenous contrast administration after premedication with oral hydration and N-acetylcysteine.Material and methodsThis prospective observational study included 112 patients with chronic renal failure (glomerular filtration rate (GFR) 30 mL—60 mL/min/1.73 m²) scheduled for computed tomography with intravenous iodinated contrast material. We recorded demographic variables, dose of contrast material, diabetes mellitus, hypertension, and serum hemoglobin. We measured serum creatinine and GFR after premedication and after the CT examination. We summarized variables as means, standard deviations, and percentages. We used the Wilcoxon and Mann-Whitney tests to compare pre- and post-CT values and Pearson's r to analyze correlations.ResultsIncidence acute kidney injury: 0.9%; 95%CI: 0.36—1.4. Mean difference between pre- and post-CT creatinine: 0.04; 95%CI: 0.002—0.09, p < 0.004. Mean difference between pre- and post-CT GFR: -3.06; 95%CI: -4.66— -1,47), p < 0.001.ConclusionsThe incidence of contrast-induced nephropathy in patients with chronic renal failure and GFR 30 mL—60 mL/min/1.73 m² is low. The biomarkers of renal function analyzed improve in patients who receive premedication and the minimum dose of contrast material.     

CT-guided Bipolar and Multipolar Radiofrequency Ablation (RF Ablation) of Renal Cell Carcinoma: Specific Technical Aspects and Clinical Results

Purpose

This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies.

Methods

We included 22 consecutive patients (3 women; age 74.2 ± 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 ± 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated.

Results

Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 ± 13.6 min and 43.7 ± 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 ± 8.8 months, local recurrence-free survival was 14.4 ± 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 ± 16.6 ml/min/1.73 m² before RF ablation vs. 47.2 ± 11.9 ml/min/1.73 m² after RF ablation; not significant).

Conclusions

CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.     

Long-Term Survival after Percutaneous Radiofrequency Ablation of Pathologically Proven Renal Cell Carcinoma in 100 Patients

PurposeTo determine the long-term survival of patients treated with percutaneous radiofrequency (RF) ablation for pathologically proven renal cell carcinoma (RCC).Materials and MethodsIn this single-center retrospective study, 100 patients with 125 RCCs (100 clear-cell, 19 papillary, and 6 chromophobe) 0.8–8 cm in size treated with RF ablation were evaluated at a single large tertiary-care center between 2004 and 2015. Technical success, primary and secondary technique efficacy, and pre- and postprocedural estimated glomerular filtration rate (eGFR) at 3–6 months and 2–3 years were recorded. Overall survival, cancer-specific survival, and local tumor progression–free survival were calculated by Kaplan–Meier survival curves. Complications were classified per the Clavien–Dindo system. Statistical testing was done via χ² tests for proportions and paired t test for changes in eGFR. Statistical significance was set at α = 0.05.ResultsOverall technical success rate was 100%, and primary and secondary technique efficacy rates were 90% and 100%, respectively. Median follow-up was 62.8 months, ranging from 1 to 120 months. The 10-year overall, cancer-specific, and local progression–free survival rates were 32%, 86%, and 92%, respectively. The number of ablation probes used was predictive of residual unablated tumor (P < .001). There were no significant changes in preprocedure vs 2–3-years postprocedure eGFR (65.2 vs 62.1 mL/min/1.73 m²; P = .443). There was a 9% overall incidence of complications, the majority of which were grade I.ConclusionsImage-guided percutaneous RF ablation of RCCs is effective at achieving local control and preventing cancer-specific death within 10 years from initial treatment.     

Stereotactic Body Radiotherapy for Stage I Renal Cell Carcinoma: National Treatment Trends and Outcomes Compared to Partial Nephrectomy and Thermal Ablation

PurposeTo assess use of stereotactic body radiotherapy (SBRT) for stage I renal cell carcinoma (RCC) and compare outcomes with thermal ablation and partial nephrectomy (PN).Materials and MethodsThe 2004–2015 National Cancer Database was investigated for histopathologically proven stage I RCC treated with PN, cryoablation, radiofrequency (RF) or microwave (MW) ablation, or SBRT. Patients were propensity score–matched to account for potential confounders, including patient age, sex, race, comorbidities, tumor size, histology, grade, tumor sequence, administration of systemic therapy, treatment in academic vs nonacademic centers, treatment location, and year of diagnosis. Overall survival (OS) was evaluated with Kaplan-Meier plots, log-rank tests, and Cox proportional hazards models.ResultsA total of 91,965 patients were identified (SBRT, n = 174; PN, n = 82,913; cryoablation, n = 5,446; RF/MW ablation, n = 3,432). Stage I patients who received SBRT tended to be older women with few comorbidities treated at nonacademic centers in New England states. After propensity score matching, a cohort of 636 patients was obtained with well-balanced confounders between treatment groups. In the matched cohort, OS after SBRT was inferior to OS after PN and thermal ablation (PN vs SBRT, hazard ratio [HR] = 0.29, 95% confidence interval [CI] 0.19–0.46, P < .001; cryoablation vs SBRT, HR = 0.40, 95% CI 0.26–0.60, P < .001; RF/MW ablation vs SBRT, HR = 0.46, 95% CI 0.31–0.67, P < .001). Compared with PN, neither cryoablation nor RF/MW ablation showed significant difference in OS (cryoablation vs PN, HR = 1.35, 95% CI 0.80–2.28, P = .258; RF/MW ablation vs PN, HR = 0.64, 95% CI 0.95–2.55, P = .079).ConclusionsCurrent SBRT protocols show lower OS compared with thermal ablation and PN, whereas thermal ablation and PN demonstrate comparable outcomes.     

Partial Nephrectomy versus Thermal Ablation for Clinical Stage T1 Renal Masses: Systematic Review and Meta-Analysis of More than 3,900 Patients

Purpose

A systematic review and meta-analysis of clinical trials was undertaken to compare percutaneous thermal ablation versus partial nephrectomy (PN) for stage T1 renal tumors.

肾动态显像评价肾积水患者肾功能的应用价值

目的 探讨肾动态显像Gates法测定肾小球滤过率（GFR）（gGFR）在肾积水和非肾积水肾病中的应用价值。 方法 选取2015年1月至2017年1月同时接受双血浆法测定GFR（rGFR）和gGFR的肾积水患者和非肾积水肾病患者,肾积水患者191例,其中男性97例、女性94例,年龄（43.35±15.91）岁;非肾积水肾病患者133例,其中男性82例、女性51例,年龄（55.31±13.54）岁。参照美国慢性肾脏病及透析的临床实践指南,将肾积水患者和非肾积水肾病患者分别分为肾功能正常组和轻、中、重度慢性肾衰竭组,对每组gGFR和rGFR进行分析比较,并计算两种方法的差值（ΔGFR）。不同肾功能组的比较采用单因素方差分析（ANOVA）,若差异有统计学意义,则行LSD-t检验法进行两两比较。gGFR和rGFR的比较采用配对t检验;相关性采用Pearson相关分析;一致性分析用Bland-Altman检验。 结果 肾积水和非肾积水肾病患者的gGFR比rGFR高,且前者的差异有统计学意义[（70.60±22.58） mL/（1.73 m2·min） vs. （58.67±20.49） mL/（1.73 m2·min）,t=9.335,P=0.000];与非肾积水肾病患者比较,肾积水患者gGFR和rGFR的相关性（r=0.692,P=0.000）较低。在肾积水患者中,轻、中、重度慢性肾衰竭组的gGFR均明显高于rGFR[（81.01±18.40） mL/（1.73 m2·min） vs. （71.03±7.74） mL/（1.73 m2·min）、（60.98±18.28） mL/（1.73 m2·min） vs. （45.85±7.60） mL/（1.73 m2·min）、（42.88±16.14） mL/（1.73 m2·min） vs. （23.65±4.04） mL/（1.73 m2·min）],差异均有统计学意义（t=4.559、8.398、4.480,均P<0.05）;中度慢性肾衰竭组gGFR和rGFR的相关性（r=0.461,P=0.000）最高;肾功能正常组和轻、中、重度慢性肾衰竭组患者的ΔGFR逐渐增高,分别为（?1.61±14.05）、（9.99±18.81）、（15.14±16.54）、（19.23±15.48）mL/（1.73 m2·min）,差异有统计学意义（F=5.595,P=0.001）; 有5.76%（11/191,>5%）的点在一致性界限（L_OA）之外,gGFR和rGFR的一致性较差。在非肾积水肾病患者中,轻度慢性肾衰竭组的gGFR明显低于rGFR[（66.08±8.97） mL/（1.73 m2·min） vs. （70.59±8.08） mL/（1.73 m2·min）],差异有统计学意义（t=?3.472,P<0.05）,中、重度慢性肾衰竭组的gGFR高于rGFR[（45.99±9.76） mL/（1.73 m2·min） vs. （43.83±8.29） mL/（1.73 m2·min）、（26.25±8.57） mL/（1.73 m2·min）vs.（20.19±5.72） mL/（1.73 m2·min）],差异均有统计学意义（t=2.095、4.907,均P<0.05）;轻度慢性肾衰竭组gGFR和rGFR的相关性（r=0.737,P=0.000）最高;肾功能正常组和轻、中、重度慢性肾衰竭组患者的ΔGFR逐渐增高,分别为（?5.64±16.64）、（?4.51±6.23）、（2.16±7.71）、（6.06±6.87）mL/（1.73 m2·min）,差异有统计学意义（F=9.446,P=0.000）;有3.01%（4/133,<5%）的点在L_OA之外,gGFR和rGFR的一致性较好。 结论 肾动态显像Gates法评估肾积水患者的GFR价值有限,应参考双血浆法的定量结果和其他检查结果进行综合分析判断。     

Carotid stenting with low-dose contrast medium for patients with moderate-to-severe chronic renal insufficiency: Keyhole carotid stenting

Herein, we describe a new carotid stenting approach for four patients with moderate-to-severe chronic renal insufficiency, who have a glomerular filtration rate (GFR) between 15 and 59 mL/min/1.73 m², using a minimum dose of contrast medium (12 mL at a 50% dilution) and SmartMask™ technology as an alternative to carotid endarterectomy.     

Comparison of methods for determination of glomerular filtration rate: Tc-99m-DTPA renography, predicted creatinine clearance method and plasma sample method

Background: The gamma camera uptake method with Tc-99m-DTPA is simple and less time consuming for the determination of the glomerular filtration rate (GFR). However, its diagnostic accuracy is debated. Gates’ method and predicted creatinine clearance method were compared with plasma clearance method with Tc-99m-DTPA for the measurement of GFR.Materials and Methods: Tc-99m-DTPA renography was performed on 133 patients (69 males and 64 females; age range being 24 to 84 years) with a wide range of renal function. The GFR was determined simultaneously by 3 methods; (1) gamma camera uptake method (modified Gates, Gates); (2) predicted creatinine clearance method (Cockcroft-Gault, CG); (3) single- or two-plasma clearance method (plasma sample clearance method, PSC). The PSC was chosen as a reference.Results: The regression equation of the Gates and the CG against the PSC wasY=11.89 + 1.041X (r=0.790, p<0.001, RMSE=23.55 ml/min/1.73 m²) andY=8.845+0.7899X (r=0.8270, p<0.001, RMSE =16.27 ml/min/1.73 m²), respectively. In comparison with the GFR by PSC, the Gates tended to everestimate the GFR, and contrarily the CG tended to underestimate the GFR.Conclusion: The Gates correlates well with the PSC. However, the Gates is even less precise than the CG. The Gates’ method in Tc-99m-DTPA renography is not suitable for the estimation of GFR in routine practice.     

Concomitant weekly cisplatin-based chemoradiotherapy in head and neck cancer: the value of a second measured glomerular filtration rate during treatment

Objectives:To assess the efficacy of the second measured glomerular filtration rate (GFR) during the course of weekly cisplatin-based chemoradiotherapy in head and neck cancer.Methods:Data was collected on consecutive 221 head and neck cancer patients who underwent cisplatin-based chemoradiotherapy.Results:68% patients managed to complete at least five out six proposed cycles of cisplatin, with a cumulative dose of ≥200 mg/m ² . 181 patients underwent second measured GFR and it showed a mean fall in measured GFR by 12.0 ml/min/1.73 m ² (p < 0.0001). Out of these 181 patients, in 16 patients (9%), the decision to discontinue cisplatin was purely based on a low second measured GFR (below 50 ml/min/1.73 m ² ).Conclusion:Our study has shown that obtaining a second measured GFR is valuable in 9% of these patients. We propose that this should be considered as a standard procedure in these settings and also should be considered incorporating this additional safety measure, into future clinical trials as a mandatory procedure.Advances in knowledge:To the best of author’s knowledge, this is first study of its kind. The results of our study suggest that it should be a standard procedure of obtaining a second GFR in these settings.