Evaluation of the Cockroft-Gault, Jelliffe and Wright formulae in estimating renal function in elderly cancer patients

Impact and consequences of the error of estimated GFR in patients with heart failure

Heart failure is a highly prevalent disease, which courses with frequent readmissions, mainly by Acute Heart Failure (AHF). Reduced renal function is associated with increased mortality in patients with HF. Therefore, an accurate and precise evaluation of renal function in patients with HF is crucial. The error of estimated GFR (eGFR) is wide and common, showing a ± 30% variability compared to measured GFR (mGFR). However, there is no evidence on the error of formulas in reflecting real renal function and particularly the consequences of this error in patients with AHF. This is a prospective study comparing the impact of mGFR versus eGFR in the onset of cardiovascular (CV) outcomes in patients with AHF. This was tested with cox survival analysis. Measured GFR was determined by the plasma clearance of iohexol-dbs and eGFR by Cockroft-Gould, MDRD, CKD-EPI creatinine, CKD-EPI cystatin-C and CKD-EPI creatinine + cystatin-C equations formulas. Also the agreement between mGFR and eGFR was analyzed. A total of 90 patients were included. Average age was 66 (± 12 years) and 52 (58%) were male. Of them 53 patients (59%) had a cardiovascular event during follow-up, 22 fatal (41%). The agreement between mGFR and eGFR indicated moderate precision and accuracy (concordance correlation coefficient of 0.77; CI = 0.73-0.82). In multiple cox survival analysis, mGFR was significantly associated with cardiovascular events together with NTproBNP, BMI, LVEF and previous coronary artery disease (p = 0.037; HR = 0.98, 95% CI = 0.95-0.99). Estimated GFR by formulas was not significant. In patients with AHF the error of formulas is large, frequent and random, also, mGFR and not eGFR predicted future CV events. The error of eGFR may have clinical consequences in specific subpopulations.

Glomerular filtration rate measurement during platinum treatment for urothelial carcinoma: optimal methods for clinical practice

BACKGROUND

We assessed the accuracy of four estimated glomerular filtration rate (eGFR) methods: MDRD, Cockcroft-Gault, CKD-EPI, and Wright.

METHOD

The four methods were compared to measure GFR (mGFR) in patients with urothelial urinary tract cancer (T2-T4bNxMx) receiving platinum-based chemotherapy at Rigshospitalet, Copenhagen, from January 2019 to December 2021. Using standardized assays, creatinine values were measured, and mGFR was determined using Technetium-99 m diethylenetriaminepentaacetic acid (Tc-99 m-DTPA) or Cr-51-ethylenediaminetetraacetic acid (Cr-51-EDTA) plasma clearance. Patients (n = 146) with both mGFR and corresponding creatinine values available were included (n = 345 measurements).

RESULTS

The CKD-EPI method consistently demonstrated superior accuracy, with the lowest Total Deviation Index of 21.8% at baseline and 22.9% for all measurements compared to Wright (23.4% /24.1%), MDRD (26.2%/25.5%), and Cockcroft-Gault (25.x%/25.1%). Bland Altman Limits of agreement (LOA) ranged from - 32 ml/min (Cockcroft-Gault) to + 33 ml/min (MDRD), with CKD-EPI showing the narrowest LOA (- 27 ml/min to + 24 ml/min and lowest bias (0.3 ml/min). Establishing an eGFR threshold at 85 ml/min-considering both the lower limit of agreement (LOA) and the minimum cisplatin limit at 60 ml/min-allows for the safe omission of mGFR in 30% of patients in this cohort.

CONCLUSION

CKD-EPI equation emerged as the most suitable for estimating kidney function in this patient group although not meeting benchmark criteria. We recommend its use for initial assessment and ongoing monitoring, and suggest mGFR for patients with a CKD-EPI estimated GFR below 85 ml/min. This approach could reduce costs and decrease laboratory time for 30% of our UC patients.

Practical implications to contemplate when considering radical therapy for stage III non-small-cell lung cancer

The type of patients with stage III non-small-cell lung cancer (NSCLC) selected for concurrent chemoradiotherapy (cCRT) varies between and within countries, with higher-volume centres treating patients with more co-morbidities and higher-stage disease. However, in spite of these disease characteristics, these patients have improved overall survival, suggesting that there are additional approaches that should be optimised and potentially standardised. This paper aims to review the current knowledge and best practices surrounding treatment for patients eligible for cCRT. Initially, this includes timely acquisition of the full diagnostic workup for the multidisciplinary team to comprehensively assess a patient for treatment, as well as imaging scans, patient history, lung function and genetic tests. Such information can provide prognostic information on how a patient will tolerate their cCRT regimen, and to perhaps limit the use of additional supportive care, such as steroids, which could impact on further treatments, such as immunotherapy. Furthermore, knowledge of the safety profile of individual double-platinum chemotherapy regimens and the technological advances in radiotherapy could aid in optimising patients for cCRT treatment, improving its efficacy whilst minimising its toxicities. Finally, providing patients with preparatory and ongoing support with input from dieticians, palliative care professionals, respiratory and care-of-the-elderly physicians during treatment may also help in more effective treatment delivery, allowing patients to achieve the maximum potential from their treatments.

Fine particulate matter exposure and renal function: A population-based study among pregnant women in China

BACKGROUND

Fine particulate matter (PM_2.5) is the most serious environmental threat worldwide. The nephrotoxicity of PM_2.5 has been demonstrated in older adults, but no study has addressed the impacts of PM_2.5 exposure on renal function in pregnant women, who are recognized to be vulnerable and susceptible to PM_2.5 exposure.

OBJECTIVE

To evaluate whether exposures to PM_2.5 total mass and its chemical constituents were associated with reduced renal function among pregnant women in China.

METHODS

We measured serum concentrations of urea nitrogen (UN), uric acid (UA) and creatinine for 10,052 pregnant women in Shanghai, China. Exposures to PM_2.5 total mass and its 5 key chemical constituents during the whole pregnancy and each trimester of pregnancy was represented by satellite-based models.

RESULTS

Exposures to PM_2.5 total mass and its chemical constituents of organic matter (OM), black carbon (BC), nitrate (NO₃^-) and ammonium (NH₄⁺) were positively associated with serum levels of UN and UA, and negatively associated with estimated glomerular filtration rate (eGFR). An interquartile rang (IQR) increase in PM_2.5 total mass, OM, BC, NO₃^- and NH₄⁺ exposure in third trimester was associated with 1.33 (β = -1.33, 95% CI, -1.79, -0.87), 1.67 (β = -1.67, 95% CI, -2.26, -1.07), 1.29 (β = -1.29, 95% CI,-1.89, -0.70), 1.16 (β = -1.16, 95% CI,-1.66, -0.65) and 0.76 (β = -0.76, 95% CI, -1.08, -0.44) mL/min/1.73 m² decrease in eGFR, respectively.

CONCLUSION

We concluded that exposures to PM_2.5 during pregnancy were associated with decreased renal function among pregnant women.

Preoperative Glomerular Filtration Rate and Outcome Following Open Abdominal Aortic Aneurysm Repair

Estimated glomerular filtration rate (eGFR) can be readily calculated from serum creatinine values. It is a more sensitive prognostic indicator than serum creatinine alone in patients undergoing thoracoabdominal or endovascular abdominal aortic aneurysm repair. The value of eGFR in patients undergoing open abdominal aortic aneurysm repair remains unclear. The preoperative eGFR was calculated for patients undergoing elective open infrarenal aortic aneurysm repair. Postoperative complications, perioperative mortality, and long-term survival were compared across eGFR and serum creatinine quartiles. The eGFR identified preoperative renal dysfunction in 33% of patients, whereas serum creatinine identified renal impairment in only 11%. The eGFR correlated with perioperative morbidity and long-term survival. Serum creatinine did not correlate with perioperative mortality or long-term survival. However, it did correlate with postoperative morbidity. The eGFR is a more sensitive index of preoperative renal function than serum creatinine and correlates with survival. It should replace serum creatinine as the standard index of renal function before open abdominal aortic aneurysm repair.

Weekly dose-dense chemotherapy in first-line epithelial ovarian, fallopian tube, or primary peritoneal carcinoma treatment (ICON8): primary progression free survival analysis results from a GCIG phase 3 randomised controlled trial

BACKGROUND

Carboplatin and paclitaxel administered every 3 weeks is standard-of-care first-line chemotherapy for epithelial ovarian cancer. The Japanese JGOG3016 trial showed a significant improvement in progression-free and overall survival with dose-dense weekly paclitaxel and 3-weekly carboplatin. In this study, we aimed to compare efficacy and safety of two dose-dense weekly regimens to standard 3-weekly chemotherapy in a predominantly European population with epithelial ovarian cancer.

METHODS

In this phase 3 trial, women with newly diagnosed International Federation of Gynecology and Obstetrics stage IC-IV epithelial ovarian cancer were randomly assigned to group 1 (carboplatin area under the curve [AUC]5 or AUC6 and 175 mg/m2 paclitaxel every 3 weeks), group 2 (carboplatin AUC5 or AUC6 every 3 weeks and 80 mg/m2 paclitaxel weekly), or group 3 (carboplatin AUC2 and 80 mg/m2 paclitaxel weekly). Written informed consent was provided by all women who entered the trial. The protocol had the appropriate national research ethics committee approval for the countries where the study was conducted. Patients entered the trial after immediate primary surgery, or before neoadjuvant chemotherapy with subsequent planned delayed primary surgery. The trial coprimary outcomes were progression-free survival and overall survival. Data analyses were done on an intention-to-treat basis, and were powered to detect a hazard ratio of 0·75 in progression-free survival. The main comparisons were between the control group (group 1) and each of the weekly research groups (groups 2 and 3).

FINDINGS

Between June 6, 2011, and Nov 28, 2014, 1566 women were randomly assigned to treatment. 72% (365), completed six protocol-defined treatment cycles in group 1, 60% (305) in group 2, and 63% (322) in group 3, although 90% (454), 89% (454), and 85% (437) completed six platinum-based chemotherapy cycles, respectively. Paclitaxel dose intensification was achieved with weekly treatment (median total paclitaxel dose 1010 mg/m2 in group 1; 1233 mg/m2 in group 2; 1274 mg/m2 in group 3). By February, 2017, 1018 (65%) patients had experienced disease progression. No significant progression-free survival increase was observed with either weekly regimen (restricted mean survival time 24·4 months [97·5% CI 23·0-26·0] in group 1, 24·9 months [24·0-25·9] in group 2, 25·3 months [23·9-26·9] in group 3; median progression-free survival 17·7 months [IQR 10·6-not reached] in group 1, 20·8 months [11·9-59·0] in group 2, 21·0 months [12·0-54·0] in group 3; log-rank p=0·35 for group 2 vs group 1; group 3 vs 1 p=0·51). Although grade 3 or 4 toxic effects increased with weekly treatment, these effects were predominantly uncomplicated. Febrile neutropenia and sensory neuropathy incidences were similar across groups.

INTERPRETATION

Weekly dose-dense chemotherapy can be delivered successfully as first-line treatment for epithelial ovarian cancer but does not significantly improve progression-free survival compared with standard 3-weekly chemotherapy in predominantly European populations.

FUNDING

Cancer Research UK, Medical Research Council, Health Research Board in Ireland, Irish Cancer Society, Cancer Australia.

Comparing glomerular filtration rate equations and the impact of different creatinine assays on the assessment of renal function in cancer patients

BACKGROUND

Equations to estimate glomerular filtration rate based on serum creatinine are commonly used in cancer patients to assess renal function. However, there is uncertainty regarding which equation is most appropriate for this population and the impact of different creatinine assays.

METHODS

Measured isotopic glomerular filtration rate results from 120 oncology patients were used to evaluate and compare all four versions of the Wright equation, Cockcroft and Gault, Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration and the Janowitz and Williams formula; using eight different creatinine assays (five Jaffe, three enzymatic).

RESULTS

The enzymatic version of the Wright equation without creatine kinase performed better than the other versions for all eight creatinine assays. However, MDRD and Janowitz and Williams gave the best overall performance in this patient population. Performance was highly dependent on the creatinine assay used, for example, the percentage of results within 30% of the isotopic glomerular filtration rate (P30) ranged from 90.8% to 60.8% for MDRD.

CONCLUSION

The performance of any equation to estimate glomerular filtration rate is highly dependent on the creatinine assay used. Oncology units should assess the performance of glomerular filtration rate equations using their laboratory creatinine assay to determine whether they can be used safely and effectively in cancer patients.

Use of Estimating Equations for Dosing Antimicrobials in Patients with Acute Kidney Injury Not Receiving Renal Replacement Therapy

Acute kidney injury (AKI) can potentially lead to the accumulation of antimicrobial drugs with significant renal clearance. Drug dosing adjustments are commonly made using the Cockcroft-Gault estimate of creatinine clearance (CLcr). The Modified Jelliffe equation is significantly better at estimating kidney function than the Cockcroft-Gault equation in the setting of AKI. The objective of this study is to assess the degree of antimicrobial dosing discordance using different glomerular filtration rate (GFR) estimating equations. This is a retrospective evaluation of antimicrobial dosing using different estimating equations for kidney function in AKI and comparison to Cockcroft-Gault estimation as a reference. Considering the Cockcroft-Gault estimate as the criterion standard, antimicrobials were appropriately adjusted at most 80.7% of the time. On average, kidney function changed by 30 mL/min over the course of an AKI episode. The median clearance at the peak serum creatinine was 27.4 (9.3–66.3) mL/min for Cockcroft Gault, 19.8 (9.8–47.0) mL/min/1.73 m² for MDRD and 20.5 (4.9–49.6) mL/min for the Modified Jelliffe equations. The discordance rate for antimicrobial dosing ranged from a minimum of 8.6% to a maximum of 16.4%. In the event of discordance, the dose administered was supra-therapeutic 100% of the time using the Modified Jelliffe equation. Use of estimating equations other than the Cockcroft Gault equation may significantly alter dosing of antimicrobials in AKI.

Carboplatin Dosing Accuracy by Estimation of Glomerular Filtration versus Creatinuria in Cancer Patients

Background: The glomerular filtration rate (GFR) is essential for calculating the dose and the monitoring of carboplatin. Although GFR measurement (mGFR) by external markers is ideal, in most cases these are not employed; the most used method is GFR estimation (eGFR) by formulae, hence the need to identify the formula with the best performance. Methods: Patients admitted between 2011 and 2017 and diagnosed with ovarian, endometrial, lung, esophageal, or testicular cancer were assessed retrospectively. The accuracy of the carboplatin dose calculated by creatinine concordance and by the Cockroft-Gault (CG), CKD-EPI, MDRD, Wright, and Jelliffe formulae was assessed using the intraclass correlation coefficient. Results: Fifty-six medical histories were analyzed. The best accuracy was observed between the Wright formula (i.e., 0.71) and the dose calculated based on the 24-h creatinine clearance. Stratification by CKD was made in depurations < 60 mL/min, where the Jelliffe value was excellent (i.e., 0.75). In depurations ≥60 mL/min, CKD-EPI was the best formula, with an accuracy of 0.65. CG was the formula with the worst performance in calculating the dose and glomerular filtration, losing its usefulness with very low filtrations. Conclusions: GFR formulae and calculation of the carboplatin dose have good accuracy with the GFR obtained based on the 24-h creatinine clearance, with the Wright formula being the one with best performance and CG the one with worst performance.

Pharmacokinetics of Chemotherapy in the Older Patient

Background

The number of individuals aged 65 years and older is growing rapidly, and the majority of cancers are diagnosed in this age group. Age-related changes in physiology can affect chemotherapy pharmacokinetics and pharmacodynamics in older patients.

Methods

We review the literature regarding the impact of age on the pharmacokinetics of commonly used chemotherapy drugs and discuss age-related changes in physiology and pharmacology that can affect chemotherapy tolerance in older patients.

Results

The data on age-related changes in chemotherapy pharmacokinetics are conflicting. While a few studies report age-related differences in chemotherapy pharmacokinetics, most found no significant difference or subtle differences in pharmacokinetics with aging. A difference in pharmacodynamics was commonly seen, however, with older patients at increased risk of myelosuppression and toxicity from age-related decline in organ function. The majority of these studies were performed in a small cohort of patients, thus limiting the generalizability of these results.

Conclusions

Additional studies are needed to address the pharmacokinetics and pharmacodynamics of cancer therapies in the older patient. Multicenter pharmacokinetic studies of adequate sample size, which include a thorough evaluation of physiologic factors and geriatric assessment parameters, would provide further insight into the factors affecting treatment tolerance. These studies would also help to guide appropriate chemotherapy dosing and interventions in order to maximize efficacy and minimize toxicity in the older patient.

Tolerance to Chemotherapy in Elderly Patients with Cancer

Background

Due to demographic changes, the number of elderly people with cancer will increase in the next decades. In the past, elderly patients with cancer were often excluded from clinical trials. Chronological age has been considered a risk factor for increased toxicity and reduced tolerance to chemotherapy.

Methods

We present a review on toxicity of chemotherapy and factors associated with toxicity in elderly patients with cancer, and we discuss chemotherapeutic agents and treatment options in treating this patient population.

Results

Age is a risk factor for increased toxicity to chemotherapy and decreased tolerance. However, few trials have been reported with adjustment for age-associated changes such as impairment of functional status and increased comorbidity, which also show an independent association with increased toxicity. Published data may include several biases, such as referral and publication bias.

Conclusions

Decision making in elderly cancer patients should be based on the results of a geriatric assessment. Patients with few or no limitations should be treated as younger patients are treated. Data with a high level of evidence are unavailable for patients showing moderate or severe limitations in a geriatric assessment.

Renal assessment using CKD-EPI equation is useful as an early predictor of contrast- induced nephropathy in elderly patients with cancer

OBJECTIVES

To assess respective roles of serum creatinine (SCr) alone and estimated glomerular filtration rate (eGFR) as an early predictor for contrast-induced nephropathy (CIN) in elderly patients with cancer.

MATERIALS AND METHODS

eGFR of 348 patients at 65years or older with malignancy who underwent contrast-enhanced computed tomography (CECT) were calculated. eGFR was calculated based on the following three equations: Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI); Modification of Diet in Renal Disease Study (MDRD); Cockcroft-Gault (CG). CIN was subdivided into two groups: CIN_25% (SCr increase >25% but ≤0.5mg/dl), and CIN_0.5 (SCr increase >0.5mg/dl). The occurrence and clinical outcomes of CIN were determined according to SCr and eGFR.

RESULTS

After CECT, CIN occurred in 50 (14.4%) patients, including 33 CIN_25% patients and 17 CIN_0.5 patients. CIN_0.5 was significantly correlated with prolonged hospitalizations and increased in-hospital mortality, but not CIN_25%. Despite SCr<1.5mg/dl, preexisting renal insufficiency (RI) was observed in 47 (13.5%) patients based on CKD-EPI equation, 50 (14.4%) patients based on MDRD equation, and 144 (41.4%) patients based on CG formula. In preexisting RI, the prevalence of CIN_0.5 had an odds ratio of 15.02 (5.24 to 43.07) based on CKD-EPI equation, 13.73 (4.81 to 39.20) based on MDRD equation, and 5.03 (1.60 to 15.75) based on CG formula.

CONCLUSION

In elderly patients with cancer who visit the emergency department, renal assessment before CECT using CKD-EPI equation was superior to SCr alone, MDRD equation, or CG formula in predicting the occurrence of CIN related CECT.

Laboratory monitoring in oncology

Objectives. To educate pharmacists about the application of laboratory values in oncology.

Methods. Research on drugs used in cancer therapy was conducted using multiple sources, including primary, secondary and tertiary references. Online searches were conducted on Medline (1966-2004), EMBASE (1996-2004) and Ovid databases, using a drug's generic name and key words, such as ‘adverse effects’, ‘hematotoxicity’, ‘renal toxicity’, ‘hepatotoxicity’, ‘cardiotoxicity’, ‘organ dysfunction’, and terms describing chemotherapy-related toxicity, such as ‘tumour lysis syndrome’.

Results. Laboratory monitoring in oncology was separated into the hematologic, hepatic, renal, cardiovascular and pulmonary systems. Laboratory tests applicable to each system are discussed. In addition, tests pertaining to specific drugs used in cancer therapy are explained. This information was compiled into a comprehensive continuing pharmacy education module.

Conclusion. Laboratory monitoring assists the pharmacist in the monitoring of chemotherapy. A general understanding of common tests used in cancer therapy and knowledge specific to drugs used can help the pharmacist tailor drug therapy monitoring.

Dose-banding of carboplatin: rationale and proposed banding scheme

Background. In dose-banding (DB) prescribed doses of cancer chemotherapy are fitted to doseranges or ‘bands’ and standard doses for each band are provided using a selection of pre-filled infusions or syringes, either singly or in combination. DB is used for several drugs where dose is based on body surface area. No DB-scheme has been reported for carboplatin, which, in clinical practice, is routinely dosed according to renal function.

Study objective. To assess the rationale for DB of carboplatin with regards to factors that influence dosing accuracy, develop a DB scheme, and discuss its potential use and limitations.

Methods. Prospective evaluations of carboplatin area under the plasma concentration – time curve (AUC) following application of the Calvert-formula were identified by a literature search. A relevant carboplatin dose range for construction of a DB-scheme with Calvert-formula based doses was obtained from published glomerular filtration rate distributions for patients receiving carboplatin.

Results. A DB-scheme was developed for individually calculated carboplatin doses of 358–1232 mg, with 35 mg increments between each standard dose and a maximum deviation of 4.7% from prescribed dose. The proposed DB-scheme covers the GFR-ranges 47–221 mL/min and 26–151 mL/min for patients receiving doses based on the target AUCs of 5 and 7 mg/mL/min, respectively.

Conclusion. There is a strong scientific rationale to support DB of carboplatin. The proposed banding scheme could introduce benefits to patients and healthcare staff but, as with other DB schemes, should be validated with prospective clinical and pharmacokinetic studies to confirm safety and efficacy.

Effect of Pretreatment Renal Function on Treatment and Clinical Outcomes in the Adjuvant Treatment of Older Women With Breast Cancer: Alliance A171201, an Ancillary Study of CALGB/CTSU 49907

PURPOSE

CALGB 49907 showed the superiority of standard therapy, which included either cyclophosphamide/doxorubicin (AC) or cyclophosphamide/methotrexate/fluorouracil over single-agent capecitabine in the treatment of patients age ≥ 65 with early-stage breast cancer. The treatment allowed dosing adjustments of methotrexate and capecitabine for pretreatment renal function. The purpose of the current analysis was to assess the relationship between pretreatment renal function and five end points: toxicity, dose modification, therapy completion, relapse-free survival, and overall survival.

METHODS

Pretreatment renal function was defined as creatinine clearance (CrCl) using the Cockcroft-Gault equation. Multivariable logistic and proportional hazards regression were used to model separately for each regimen the relationship between CrCl and the first three binary end points and the last two time-to-event end points, respectively, after adjusting for variables of prognostic importance.

RESULTS

Six hundred nineteen assessable patients were analyzed. The incidence of stage III (moderate) or stage IV (severe) renal dysfunction was 72%, 64%, and 75% for treatment with cyclophosphamide/methotrexate/fluorouracil, AC, and capecitabine, respectively. There was no relationship for any regimen between pretreatment renal function and the five end points. For AC, as CrCl increased, the odds of nonhematologic toxicity decreased (P = .008), whereas for capecitabine, as CrCl increased, the odds of experiencing toxicity of any type also increased (P = .035). Patients with renal insufficiency who received dose modifications were not at increased risk for complications compared with those who did not have renal insufficiency and received a full dose.

CONCLUSION

Excluding from clinical trials patients with renal insufficiency but good performance status on the basis of concern of excessive hematologic toxicity or poor outcomes may not be justified with appropriate dosing modifications. Results should be considered in the design of clinical trials for older patients.

Effect of age on drug metabolism in women with breast cancer

INTRODUCTION

The aging of the population will increase the number of breast cancer patients requiring treatment in both the adjuvant and metastatic setting. Hormones, chemotherapy and targeted drugs all have a role in treatment. Older patients have been underrepresented in clinical trials making evidence-based decisions difficult. The increase in comorbidity and aging, polypharmacy and changes in function make pharmacotherapy decisions more complicated. Knowledge of the issues is critical in the prescribing of effective and safe therapy. There are factors associated with advancing age that can result in pharmacokinetic and pharmacodynamic variations in processing of hormonal agents, chemotherapy and targeted drugs.

AREAS COVERED

A review of the literature pertaining to pharmacokinetic changes in aging in breast cancer was untaken. Studies are reviewed involving single agents and some combinations.

EXPERT OPINION

Older patients should be considered for standard therapies. Their specific problems need to be evaluated by geriatric-specific assessment including functional status, end organ dysfunction and polypharmacy. There are few instances for age-related changes in pharmacokinetics and when present are usually not clinically significant. When changes are present, they are often the result of comorbidity, drug interactions and drug scheduling issues. The older patients may be more sensitive to certain toxicities such as cardiac toxicity, neuropathy and myelosuppression.

Individualizing pharmacotherapy in patients with renal impairment: the validity of the Modification of Diet in Renal Disease formula in specific patient populations with a glomerular filtration rate below 60 ml/min. A systematic review

Background

The Modification of Diet in Renal Disease (MDRD) formula is widely used in clinical practice to assess the correct drug dose. This formula is based on serum creatinine levels which might be influenced by chronic diseases itself or the effects of the chronic diseases. We conducted a systematic review to determine the validity of the MDRD formula in specific patient populations with renal impairment: elderly, hospitalized and obese patients, patients with cardiovascular disease, cancer, chronic respiratory diseases, diabetes mellitus, liver cirrhosis and human immunodeficiency virus.

Methods and Findings

We searched for articles in Pubmed published from January 1999 through January 2014. Selection criteria were (1) patients with a glomerular filtration rate (GFR) < 60 ml/min (/1.73m²), (2) MDRD formula compared with a gold standard and (3) statistical analysis focused on bias, precision and/or accuracy. Data extraction was done by the first author and checked by a second author. A bias of 20% or less, a precision of 30% or less and an accuracy expressed as P₃₀% of 80% or higher were indicators of the validity of the MDRD formula. In total we included 27 studies. The number of patients included ranged from 8 to 1831. The gold standard and measurement method used varied across the studies. For none of the specific patient populations the studies provided sufficient evidence of validity of the MDRD formula regarding the three parameters. For patients with diabetes mellitus and liver cirrhosis, hospitalized patients and elderly with moderate to severe renal impairment we concluded that the MDRD formula is not valid. Limitations of the review are the lack of considering the method of measuring serum creatinine levels and the type of gold standard used.

Conclusion

In several specific patient populations with renal impairment the use of the MDRD formula is not valid or has uncertain validity.

Comparative performances of the new chronic kidney disease epidemiology equations incorporating cystatin C for use in cancer patients

AIM

In cancer patients receiving chemotherapy treatment, accurate assessment of kidney function is required. The aim of our study was to investigate whether the inclusion of cystatin C together with creatinine in prediction equations would improve the prediction of glomerular filtration rate (GFR).

METHODS

Plasma creatinine and cystatin C were analyzed in 155 patients (cancer, n = 80, kidney donors, n = 75) undergoing (99m) Technetium diethylenepentaacetic (Tc-DTPA) GFR clearance. Equations by the CKD-EPI (chronic kidney disease epidemiology) group (creatinine-, creatinine + cystatin C-, cystatin C-based, respectively) and Cockcroft-Gault were compared with Tc-DTPA GFR by difference plots, receiver operator characteristics curve analysis, root mean square error, chi-squared analysis and percentage concordance according to carboplatin dosage. Comparisons between two creatinine methodologies (enzymatic vs Jaffe) were also performed.

RESULTS

In the overall group, the combination creatinine and cystatin C equation had 69% of results within 20% of GFR (P20), a sensitivity of 86.3% and a specificity of 73.1% to detect reduced GFR at <90 mL/min/1.73 m(2), and a concordance of 78%. In contrast, the traditional Cockcroft-Gault equation had a P20 of 38.0%, with a large underestimation to predict GFR, thereby accounting for approximately 45% of dosing discordance. No obvious differences were obtained when comparing the performance of equations using the two creatinine methodologies.

CONCLUSION

The inclusion of cystatin C in the CKD-EPI equations improved the prediction of kidney function in the overall population, although probably not sufficiently for it to be favored over radioisotopic GFR for guiding chemotherapy. More research is warranted to further improve estimated GFR equations for these purposes.

The Practical Implications of Using Estimated GFR as the Presumed Reference Variable to Estimate Transplant Chronic Kidney Disease

We determined the proportions of matched kidney transplant isotope GFRs (iGFRs) to the estimated functions (eGFRs) calculated from Isotope Dilution Mass Spectrometry (IDMS), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Cockcroft-Gault (CG) equations. One thousand four hundred and three iGFR/eGFR pairs on 390 kidney transplant patients were compared considering the iGFR or eGFR as the reference or test variable. Conformity of iGFR to CG estimates demonstrated the least bias of 1.3±18.4 mL/min/1.73 m2 (compared to 1.5±19.4 and - 2.2±19.2 for IDMS and CKDI-EPI, P<0.05) and CKD-EPI estimates the highest precision of 4.1±41.8 (compared to 11.3±43.9 for IDMS and 5.7±37.3 for CG; P<0.05). IDMS eGFR cut off less than 60 and less than 30 mL/min/1.73m2 were correctly matched by iGFR in 79.4% and 49.1% of the times, while CKD-EPI was matched by iGFR in 83.5% and 52.5%. CG was matched in 78.3% and 53.6%. IGFR cut off levels of less than 60, and less than 30 mL/min/1.73m2 were predicted by IDMS in 83.8% and 64.0% of the times. CKD-EPI was correct in 77.8% and 59.0% and CG in 82.5% and 41.6%, respectively. Transplant eGFR results obtained by CKD-EPI or CG are likely to be more precise and less biased than IDMS.

Retooling the creatinine clearance equation to estimate kinetic GFR when the plasma creatinine is changing acutely

It is often desirable to estimate the GFR (eGFR) at the bedside to assess AKI or renal recovery. Current eGFR equations estimate kidney function when the plasma creatinine is stable, but do not work if the plasma creatinine is changing rapidly. To analyze kidney function in the acute setting, a simple formula is proposed that requires only a modest number of inputs that are readily obtainable from clinical laboratory data. The so-called kinetic eGFR (KeGFR) formula is derived from the initial creatinine content, volume of distribution, creatinine production rate, and the quantitative difference between consecutive plasma creatinines over a given time. For that period, the deciphered creatinine excretion then yields the creatinine clearance rate. The additional formula variables needed are any steady-state plasma creatinine, the corresponding eGFR by an empirical formula, and the maximum increase in creatinine per day if anuric. The kinetic formula complements clinical intuition but also adds a quantitative and visual dimension to the assessment of kidney function, demonstrated by its analysis of GFRs underlying the plasma creatinine fluctuations in several scenarios of AKI or renal recovery. Deduced from first principles regarding the physiology of creatinine balance, the KeGFR formula enhances the fundamental clearance equation with the power and versatility to estimate the kidney function when the plasma creatinine is varying acutely.

Long term renal toxicity of ifosfamide in adult patients--5 year data

Ifosfamide is indicated as first line treatment in a variety of solid tumours in adults. It is known to be nephrotoxic and is often used following therapy with, or as concomitant therapy with other potent nephrotoxins. To date, there are sparse case reports on the incidence of acute kidney injury (AKI) or chronic kidney disease (CKD) in adults exposed to ifosfamide. The available data on the long term renal complications for patients exposed to ifosfamide are thus based entirely on the paediatric population. The aim of this study was to assess the long term effects of ifosfamide exposure on renal function in an adult population and to determine if there are any treatment or patient specific factors that contribute to long term nephrotoxicity. The mean decline in estimated glomerular filtration rate (eGFR) following the first cycle of ifosfamide was 15 ml/min/1.73 m(2). Thereafter, there was a slower but steady decline in eGFR. No patient progressed to end stage renal disease (ESRD). Patient age and concomitant exposure to carboplatin were the only two factors which significantly affected eGFR. This represents the only long term study on the nephrotoxicity of ifosfamide in adults.

A retrospective observational study on the use of capecitabine in patients with severe renal impairment (GFR <30 mL/min) and end stage renal disease on hemodialysis

Capecitabine (Xeloda) is an orally administered precursor of 5'deoxy-5-fluorouridine, which is a preferentially activated to 5-fluorouracil in tumors. It is used in the treatment of colorectal, gastric, and breast cancers. Based on a single Phase II trial, which included a total of 4 patients with severe renal impairment (GFR <30 mL/min), the manufacturer issued a 'Dear Doctor' letter contraindicating the use of capecitabine in these patients since a high rate of grade 3 and 4 adverse events were observed and because these patients tolerated shorter treatment durations.(1) We retrospectively studied 12 patients with a GFR <30 mL/min, including 2 patients with end stage renal disease on hemodialysis, who received capecitabine for mean duration of 7.1 months (1-26 months). The mean serum creatinine at the time of initiation of the drug was 2.63 mg/dL (1.8-6.4 mg/dL) and mean GFR was 20.9 mL/min (8-29 mL/min). Two patients remained on capecitabine after they progressed to end stage renal disease (ESRD) requiring hemodialysis (HD) for an additional 17 and 6 months, respectively. Most patients reported grade 1 and 2 adverse effects (AE), 2 patients reported grade 3 diarrhea and one patient died while on treatment with capecitabine. The starting dose ranged from 250 to 1000 mg/m(2), given twice daily at variable intervals. Dose modifications, with reductions of up to 50% of the starting dose, were made following reports of AEs. Serum tumor marker levels and/or follow up imaging studies were available on 9 patients. Response to capecitabine was documented in 4 patients, stable disease in 2, and disease progression in 3. We conclude that, with close monitoring of their clinical and chemical data, and with dose modification based on reported AEs, capecitabine can be safely administered to patients with severe renal impairment, including patients on hemodialysis.

An analysis of measured and estimated creatinine clearance rates in normal weight, overweight, and obese patients with gynecologic cancers

Study objective: Different equations used to estimate creatinine clearance (Clcr) in obese oncology patients can produce divergent estimated creatinine clearance values, which in turn can result in significantly different calculated carboplatin doses. Standardization of the calculation of creatinine clearance in patients of all body types is a desirable goal. The objective of our study was to examine the impact of increasing body mass index on the accuracy of creatinine clearance estimation methods and to determine the optimal equation for creatinine clearance estimation in the obese adult female cancer patient.

Design: Retrospective data analysis.

Patients: We compared the estimated creatinine clearance values produced by each of 11 equations to 24-hour creatinine clearance values measured in 119 adult female patients with gynecologic cancers grouped according to body composition.

Measurements and main results: We applied simple linear regression and Tukey mean-difference analysis to assess the relationship between estimated creatinine clearance values produced by these equations and measured creatinine clearance values for each patient. The relationship between measured creatinine clearance and estimated creatinine clearance produced by all equations displayed lower linear regression R2 values and higher limits of agreement in obese patients than in nonobese groups. Agreement between measured and estimated creatinine clearance produced by the Cockcroft-Gault equation is sensitive to the particular weight parameter incorporated and is lowest using ideal weight or actual body weight. The Cockcroft-Gault equation incorporating an intermediate weight value reduced estimation bias. The Jelliffe equation produced the lowest R2 values.

Conclusion: Available model equations are less reliable for predicting creatinine clearance in obese female cancer patients (body mass index >30) than in nonobese patients. A measured glomerular filtration rate or creatinine clearance value is most accurate in obese female cancer patients. When using Cockcroft-Gault equation for estimation in this patient population, however, an intermediate weight value (adjusted or modified-adjusted) rather than ideal or actual body weight should be used.

Analysis of patient survival in a Phase I trial of systemic targeted α-therapy for metastatic melanoma

Targeted α-therapy is an experimental approach to the management of cancer. Short range α-particle radiation from a radioisotope attached to a targeting monoclonal antibody kills targeted cancer cells. Survival results are analyzed from a previously reported Phase I study of systemic targeted α-therapy for patients with stage IV metastatic melanoma or in-transit metastases. Following intravenous administration of 46-925 MBq of the α-immunoconjugate, (213)Bi-cDTPA-9.2.27, 38 patients were followed to observe response and toxicity. Responses were measured by physical examination, computed tomography at 8 weeks and blood sampling. Toxicity was monitored by blood pathology, urine analysis, glomerular filtration rate and human antimouse antibody response. The maximum tolerance dose was not achieved as there were no adverse events of any type or level. However, an objective partial response rate of 10% was observed, with 40% stable disease at 8 weeks and a median survival of 8.9 months. These results were unexpected because of the short half-life of the (213)Bi and short range of the α-radiation. Survival analysis demonstrated melanoma-inhibitory activity, disease stage, lactate dehydrogenase and treatment effects to be significant prognostic indicators for survival.

Estimation of renal function in lung cancer patients

INTRODUCTION

In lung cancer patients treated with chemotherapy, renal function is an important parameter to be monitored. Since measurement of renal function with either isotope or creatinine clearance is time consuming and expensive, we evaluated which of the following equations: Cockcroft-Gault (CG), Wright, modification of diet in renal disease equation (MDRD), MDRD adjusted for body surface area (BSA) and chronic kidney disease epidemiology collaboration (CKD-EPI) best resembles endogenous creatinine clearance (ECC) and could therefore replace its measurement in clinical practice.

METHODS

218 lung cancer patients, who had their 24-h creatinine secretion in urine measured prior to the start of any chemotherapy, were included. Estimation of renal function was calculated and compared to ECC.

RESULTS

There were no major differences in the performance of the tested equations. Mean percentage error of more than 20% and general underestimation was common to all equations. Wright equation performed best although it describes only 43% of ECC variability. Mean measured ECC was 94 mL/min (95% confidence interval [CI]: 90-98 mL/min) and 90 mL/min for Wright equation (95% CI: 87-93 mL/min) (Supp. Fig. 3). MDRD and CKD-EPI equation performed poorest since they do not include any body size descriptor. Large deviations of differences were observed, with a median standard deviation of more than 20% and deviations from ECC exceeding 100%. Wright equation performed best, whereas, despite their leading role in the detection of renal diseases, the MDRD and CKD-EPI equation performed poorest since they do not include any body size descriptor. In the range of ECC<50 mL/(min×1.73 m(2)), the CG equation most often detected a contraindication for cisplatin use. Differences between ECC and calculated values correlated with patients' weight, BSA and body mass index when these were not included in the equation itself.

CONCLUSIONS

In evaluating the renal function of lung cancer patients, equations adjusted for body size descriptors should be preferred. Estimated renal function should be interpreted against the characteristics of patient's body size and special attention is needed when these are reaching the extremes.

Evaluation of glomerular filtration rate estimation by Cockcroft-Gault, Jelliffe, Wright and Modification of Diet in Renal Disease (MDRD) formulae in oncology patients

BACKGROUND

The aim was to evaluate the accuracy of Cockcroft-Gault, Jelliffe, Wright and Modification of Diet in Renal Disease (MDRD) formulae as a substitute for the gold standard measure of glomerular filtration rate (GFR) using chromium 51 EDTA.

PATIENTS AND METHODS

Retrospective analysis of GFR measurements in oncology patients from a University Teaching Hospital over 3 years was carried out. Bias and precision of estimates of GFR were compared with measured GFR.

RESULTS

Six hundred and sixty patients with measured GFR (median 90 ml/min, range 23-179 ml/min) were identified. Cockcroft-Gault produced the smallest bias (median percentage error -1.4%) and highest precision (median absolute percentage error 14.0%) and was the most accurate for carboplatin dosing. For patients>30% over their ideal body weight (IBW), using IBW+30% in the Cockcroft-Gault formula was more precise than using actual body weight or IBW. The Wright formula was most accurate for patients aged 70+years and patients with a body mass index (BMI)≥30 but overestimated GFR when GFR<50 ml/min.

CONCLUSIONS

When measured GFR is unavailable, we advise estimating GFR using the Cockcroft-Gault formula and using IBW+30% for patients weighing>30% over their IBW. If the GFR is ≥50 ml/min and the patient is >70 years and/or BMI≥30, the Wright formula gives the best estimate of GFR.

Effect of age on systemic exposure and haematological toxicity of carboplatin in advanced non-small cell lung cancer patients

The aim of this study was to evaluate systemic exposure to carboplatin and its haematological toxicity in patients with advanced non-small cell lung cancer both older and younger than 70 years when the target area under the curve (AUC) in elderly patients was reduced by 20%. For this purpose, a population pharmacokinetic model was developed and the haematological toxicity of the drug was assessed. A total of 33 patients received carboplatin on day 1 and gemcitabine (1250 mg/m(2) ) on days 1 and 8. This schedule was repeated every 21 days. The Calvert-Crokcoft-Gault formula was employed to calculate a dose of carboplatin with a target AUC of 5 mg/min./mL in patients under 70 years and 4 mg/min./mL in patients aged 70 or older. The data of 24 patients were treated for population modelling performed with the nonmem (University of California, San Francisco, CA, USA) approach. Haematological toxicity was evaluated for all 33 patients enrolled in the study. The carboplatin systemic exposure measured by the AUC (mg/min./mL) was 5.98 (5.45; 6.51) and 5.36 (5.02; 5.69) for the younger patients and older groups, respectively. No significant differences were observed between the two groups with respect to rates of grade 3+ anaemia, neutropenia or thrombocytopenia. In clinical practice, a target AUC of 4 mg/min./mL carboplatin is applied to patients aged 70 and over, but the actual systemic exposure to the drug is higher. This supports a target AUC of 4 mg/min./mL carboplatin for patients older than 70 years when the dose is calculated by means of the Calvert-Crokcoft-Gault formula.

Renal safety of ibandronate 6 mg infused over 15 min versus 60 min in breast cancer patients with bone metastases: a randomized open-label equivalence trial

PURPOSE

The aim of this study was to demonstrate the renal safety equivalence of ibandronate 6 mg infused over 15 min versus 60 min, in patients with bone metastases of breast cancer.

PATIENTS AND METHODS

Patients were females having breast cancer with at least one bone metastasis. Exclusion criteria were renal failure (creatinine clearance < 30 mL/min), tooth/jaw disorder or uncontrolled severe disease. Eligible patients were randomly assigned to receive nine ibandronate 6 mg i.v. infusions over either 15 min or 60 min. The primary outcome was the 95% confidence interval (CI) of the difference in creatinine clearance between groups, 28 days after the last infusion. The equivalence margin was ±8 mL/min.

RESULTS

Overall 334 patients were randomized (165-15 min infusions vs. 169 to 60 min infusions, 325 (159 vs. 166) were analyzed by intent-to-treat, and 312 (151 vs. 161) were analyzed per protocol. Per protocol, the 15 min-60 min difference in creatinine clearance [95% CI] was -3.00 [-8.18, 2.18]. By intent-to-treat, this difference was-2.91 [-7.99, 2.16]. Death and serious adverse event rates did not differ between groups. Three serious adverse events were considered related to ibandronate: an osteonecrosis of the jaw (15-min group), a pain in jaw and an enamel cracking (60-min group). Two renal failures, reported in the 60 min group, were not considered related to ibandronate. None occurred in the 15 min group.

CONCLUSION

Ibandronate may be infused over 15 min without clinically significant consequence on renal safety.

[Incidence, risk factors and prevention of cisplatin-induced nephrotoxicity in patients with lung cancer]

High-dose (75 mg/m2) cisplatin is baseline chemotherapy in lung cancer. To prevent nephrotoxicity, patients generally receive saline infusion on the day of chemotherapy prior to and following cisplatin (total of 3.5-4.0 liters during 3-4 hours). Despite these measures nephrotoxicity has remained frequent, especially among patients also suffering from cardiovascular disease or diabetes mellitus. Since 2005 several international recommendations have been formed about prevention of cisplatin nephrotoxicity. According to these recommendations: 1) renal function should not be evaluated by serum creatinine concentration; 2) evaluation of renal function should be based on calculated creatinine clearance (e.g. by the Cockcroft-Gault equation); 3) patients to be treated by high-dose cisplatin should be euvolemic and should have saline diuresis (urine NaCl concentration ~1%) of at least 100 ml/hour prior to, during and several days following the administration of cisplatin. Keeping these recommendations ensures prolonged cisplatin treatability of lung cancer patients. Moreover, decreased renal function will not limit the full dose administration of several other cytotoxic agents. Losonczy G, Máthé C, Müller V, Szondy K, Moldvay J. Incidence, risk factors and prevention of cisplatin-induced nephrotoxicity in patients with lung cancer.

[Chemotherapy in unfit bladder cancer patients]

Bladder cancer often occurs in patients with high risk of acute toxicity under chemotherapy. So-called unfit patients are a heterogenous population, sharing a contra-indication for cisplatin and presenting either chronic renal failure, and/or elderly, and/or altered performance status, and/or severe co-morbidities. Therefore, it is necessary to develop chemotherapy protocols feasible in renal insufficient patients, and well tolerated in frail patients. The medical evaluation prior to initiate chemotherapy is of major importance to screen for chronic disorders and to anticipate the potential acute complications following chemotherapy. Chemotherapy of elderly patients with severe comorbidities is a common situation in bladder cancer, and will concern all cancer patients. The evaluation of the benefit/risk ratio of the chemotherapy protocol is a typical expertise of medical oncologists, which requires to integrate the complex links between the patient, the antitumor agent, and toxicity. The physician must also have a honest dialogue to inform, advise, listen to the patients priorities. Medical oncologists have to have in mind this situation and to adapt their clinic and their vocabulary to this emerging reality.

Cancer chemotherapy in the older cancer patient

This article reviews the principles of systemic cancer treatment in older individuals. These include: assessment of physiologic age with a comprehensive geriatric assessment (CGA), adjustment of chemotherapy doses to the patient's renal function, and prevention of myelotoxicity with hemopoietic growth factors. Other complications that become more common with age include mucositis, peripheral neuropathy and cardiomyopathy. Two chronic complications of chemotherapy become more common with age, including myelodysplasia and chronic cardiomyopathy. The goal of systemic cancer treatment in the older person should include prolongation of active life-expectancy and compression of morbidity in addition to prolongation of survival and symptom management.

Impact of computerized dosing on eptifibatide-associated bleeding and mortality

OBJECTIVE

The study aimed to determine the impact on eptifibatide-associated bleeding by implementing a computerized dosing algorithm in the cardiac catheterization suite.

BACKGROUND

Excessive dosing of eptifibatide is associated with increased bleeding rates and hospital mortality. Although dosing adjustments based on renal function has been recommended, its implementation and clinical impact have not been assessed in daily practice.

METHODS

A computerized algorithm was implemented in January 2006 to calculate appropriate eptifibatide infusion dose (1 microg kg(-1) min(-1) for creatinine clearance <50 mL/min or 2 microg kg(-1) min(-1) for creatinine clearance >or=50 mL/min) using the Cockroft-Gault formula. All patients had hemoglobin measured before and the day after the procedure. Bleeding within 24 hours and mortality during hospitalization were compared in consecutive patients before and after implementation of the algorithm.

RESULTS

A total of 334 patients qualified for inclusion (pre-algorithm n = 91, post-algorithm n = 243). There was an increase in the proportion of patients receiving recommended doses of eptifibatide dosing (74.7% pre-algorithm vs 97.5% post-algorithm, P <or= .0001). Twenty-four-hour bleeding complications as classified using 3 major bleeding classification systems were reduced as was hospital mortality (4.4% vs 0%, P = .005). Packed red blood cell transfusion rates were similar between both groups (4.4% pre-algorithm vs 2.1% post-algorithm, P = .26).

CONCLUSIONS

In patients receiving eptifibatide in the catheterization laboratory before percutaneous coronary intervention, implementation of a computerized algorithm was associated with appropriate dosing and reduced bleeding and mortality.