Carboplatin Dosing in Children Using Estimated Glomerular Filtration Rate: Equation Matters

Comparison of GFR estimation equations using creatinine, cystatin C, and their combination in pediatric hematology-oncology: no single equation is superior across subgroups

BACKGROUND

Accurate assessment of renal function is essential in treating pediatric patients dosed with nephrotoxic chemotherapy. The validity of the bedside Schwartz, 5-covariate St. Jude (5SJ), CKiD-CysC-U25, combined Cr-CysC-based CysPed, and the serum creatinine-BUN-cystatin C-based CKiD (CKiD Cr-CysC) equations were evaluated in pediatric hematology and oncology patients.

METHODS

A retrospective analysis was conducted comparing estimated glomerular filtration rate (eGFR) to measured GFR (mGFR) obtained from technetium- 99 m diethylenetriaminepentaacetic acid (99 mTc-DTPA) clearance between January 2016 and May 2022. The influence of corticosteroid use and inflammation in our patient population was evaluated for effect on serum cystatin C (CysC) concentrations and mGFR.

RESULTS

All equations agreed within 2 SD of the mean difference with mGFR, but the 5SJ equation had the smallest bias followed closely by the CysPed equation. Overall accuracy (P30) was assessed, and the 5SJ, CKiD Cr-CysC, CysPed, and CKiD-Cys-U25 exhibited comparable performance. In our patient population, we did not observe an effect of corticosteroids (cumulative dosage of > 0.5 mg/kg within the past 14 days) or the presence of inflammation (CRP > 1.2 mg/L) on cystatin C concentrations or mGFR.

CONCLUSIONS

In our pediatric hematology and oncology patient population, no one estimating equation demonstrated superior accuracy and bias overall and in all subgroups. Neither corticosteroid use nor elevated CRP influenced serum CysC concentrations or eGFR.

Systematic analysis of off-label and off-guideline cancer therapy usage in a real-world cohort of 165,912 US patients

Patients with cancer may be given treatments that are not officially approved (off-label) or recommended by guidelines (off-guideline). Here we present a data science framework to systematically characterize off-label and off-guideline usages using real-world data from de-identified electronic health records (EHR). We analyze treatment patterns in 165,912 US patients with 14 common cancer types. We find that 18.6% and 4.4% of patients have received at least one line of off-label and off-guideline cancer drugs, respectively. Patients with worse performance status, in later lines, or treated at academic hospitals are significantly more likely to receive off-label and off-guideline drugs. To quantify how predictable off-guideline usage is, we developed machine learning models to predict which drug a patient is likely to receive based on their clinical characteristics and previous treatments. Finally, we demonstrate that our systematic analyses generate hypotheses about patients' response to treatments.

A single-blinded, randomized controlled trial of standard versus higher dose carboplatin-based intravenous chemotherapy for group D and E retinoblastoma

BACKGROUND

Access to intra-arterial chemotherapy for retinoblastoma in low- and middle-income countries (LMICs) is limited. There is a need to optimize the efficacy of systemic chemotherapy for advanced intraocular retinoblastoma, particularly in LMICs. The aim was to compare the efficacy of standard versus higher dose carboplatin-based intravenous chemotherapy for group D and E retinoblastoma.

METHODS

The single-center, single-blinded, randomized study was conducted during 2019-2021. Patients with newly diagnosed group D or E retinoblastoma were randomized to receive vincristine, etoposide, and standard versus higher dose (<36 months: 18.6 vs. 28 mg/kg; ≥36 months: 560 vs. 840 mg/m2 ) carboplatin. Examination under anesthesia and ultrasonography was performed at diagnosis and following three cycles of chemotherapy. Group E eyes with poor likelihood of globe/vision salvage at diagnosis were excluded.

RESULTS

Thirty-two eyes of 30 patients were analyzed: 17 group D and 15 group E eyes. The tumor response to chemotherapy with regards to regression pattern (p = .72), tumor shrinkage (diameter: p = .11, height: p = .96), subretinal seeds (p = .91), and vitreous seeds (p = .9) were comparable between the two treatment arms. The globe salvage (group D [82% vs. 67%; p = .58]; group E [12.5% vs. 29%; p = .57]) and salvage of meaningful vision (group D [100% vs. 75%; p = .13]; group E [100% vs. 50%; p = .48]) were comparable between standard and higher dose arms. No excess treatment-related toxicity was observed in the higher dose arm.

CONCLUSIONS

Higher dose carboplatin-based intravenous chemotherapy did not result in superior globe or vision salvage in group D or E retinoblastoma.