Inadvertent perioperative hypothermia prevention strategies for urology surgical patients who received a blood transfusion: A retrospective analysis

OBJECTIVES

This study aimed to establish whether hypothermia was present in patients who required a blood transfusion and underwent a urology procedure, as well as identify staff knowledge and understanding.

PATIENTS AND METHODS

A staff survey was conducted with respondents from a range of clinical settings, with some staff working across more than one area. A retrospective review of 46 medical records was conducted between January 2021 and July 2022. All data were exported into an Excel spreadsheet and analysed.

RESULTS

Staff (70%) were unaware of guidelines informing thermoregulation practices; however, 90% understood the importance of normothermia in the perioperative environment. Medical record review demonstrated temperature monitoring and intervention implementation varied across the perioperative journey, with 20% of patients hypothermic on admission and 89% of the cohort having two or more risk factors.

CONCLUSION

There is no formal process for the management of inadvertent perioperative hypothermia throughout the patient journey at the hospital. A variety of intrinsic factors (age, patient comorbidities, American Society of Anaesthesiologists score) and external factors (patient waiting times, anaesthetic modality, type of procedure, environmental influences), impact each patient's risk of inadvertent perioperative hypothermia.

A phase I study of zoledronic acid (ZA) and low-dose cyclophosphamide (CTX) in children with recurrent/refractory neuroblastoma (NB): A New Approaches to Neuroblastoma Therapy (NANT) study

10022

Background: ZA, a bisphosphonate, delays progression of bone metastases in adult malignancies. Bone metastases occur in 60% of children with advanced NB. A xenograft mouse model demonstrated ZA with low dose chemotherapy delayed progression of NB bone lesions prompting a phase I trial of ZA. Methods: Three dose levels of intravenous ZA (2, 3, or 4 mg/m2) administered every 28 days were evaluated with continuous daily oral CTX (25 mg/m2/day) in patients with recurrent/refractory NB and bone metastases. The primary objective was to determine a recommended dose of ZA for future trials. PKs with the first dose of ZA and serial serum IL-6 levels (stimulator of osteoclast activity) were evaluated. Results: 21 patients (14 male), median age 7.9 years (0.8–26.6 years), were enrolled at ZA dose levels 2 mg/m2 (n=4), 3 mg/m2 (n=3), and 4 mg/m2 (n=13). Seventy-five cycles were administered with median of 1 cycle per patient (range 1–18). Two DLT (Gr 3 hypophosphatemia) occurred at 4 mg/m2 ZA. Other Gr 3 or 4 toxicities included hypocalcemia (n = 2), elevated transaminases (n = 2), neutropenia (n = 2), anemia (n = 1), lymphopenia (n = 1), and hypokalemia (n = 1). A fracture related to osteosclerosis occurred after 18 cycles. There were no renal or dental complications. There was 1 complete response, 9 stable disease median 4.5 cycles (range 3–18), and 10 progressions (central review pending). At 4 mg/m2, mean serum IL-6 levels decreased from 3.9 pg/mL (95% CI: 2.8–5.2 pg/mL) (n = 11) to 2.9 pg/mL (95% CI: 1.8–4.4 pg/mL) after cycle 1 (n = 8). ZA PK were similar to adults. Conclusions: ZA with low dose CTX is well tolerated with evidence of clinical benefit in children with recurrent/refractory NB. The recommended ZA dose for future study is 4 mg/m2 every 28 days.

No significant financial relationships to disclose.

The impact of paediatric tracheostomy on both patient and parent

OBJECTIVE

We set out to assess the impact of paediatric tracheostomy, performed in a central London hospital, on patients and their families.

METHODS

We conducted structured interviews with caregivers of tracheostomised children using the Pediatric Tracheotomy Health Status Instrument during all in-patient admissions for airway endoscopy over a 6-month period.

RESULTS

Completed questionnaires were received from 26 caregivers, 7 (27%) of whose children had been successfully decannulated. Carers reported adverse effects on all aspects of their quality of life, including sleep, relationships, social life and ability to work. The families included in the study had gross household incomes below the mean for SE London. There is a shortfall in the provision of home nursing when compared with the needs of the caregivers.

CONCLUSIONS

Tracheostomy has wide ranging effects on the quality of life of both the patient and their caregivers. We identified the need for better pre-operative preparation where possible, and greater support for such families in the community.

Explaining racial disparities in incidence of and survival from out-of-hospital cardiac arrest

A prospective observational study of 4,653 consecutive cases of out-of-hospital cardiac arrest (OOHCA) occurring in New York City from April 1, 2002, to March 31, 2003, was used to assess racial/ethnic differences in the incidence of OOHCA and 30-day survival after hospital discharge among OOHCA patients. The age-adjusted incidence of OOHCA per 10,000 adults was higher among Blacks than among persons in other racial/ethnic groups, and age-adjusted survival from OOHCA was higher among Whites compared with other groups. In analyses restricted to 3,891 patients for whom complete data on all variables were available, the age-adjusted relative odds of survival from OOHCA among Blacks were 0.4 (95% confidence interval: 0.2, 0.7) as compared with Whites. A full multivariable model accounting for demographic factors, prior functional status, initial cardiac rhythm, and characteristics of the OOHCA event explained approximately 41 percent of the lower age-adjusted survival among Blacks. The lower prevalence of ventricular fibrillation as the initial cardiac rhythm among Blacks relative to Whites was the primary contributor. A combination of factors probably accounts for racial/ethnic disparities in OOHCA survival. Previously hypothesized factors such as delays in emergency medical service response or differences in the likelihood of receipt of cardiopulmonary resuscitation did not appear to be substantial contributors to these racial/ethnic disparities.

Decitabine (DAC) in combination with doxorubicin (DOX) and cyclophosphamide (CTX) in relapsed neuroblastoma (NBL): A Children's Oncology Group Study

9565

Background: Loss of caspase-8 expression causes resistance to apoptosis-inducing agents and potentiates metastasis in NBL. In vitro treatment of NBL cell lines with DAC results in increased caspase-8 expression and enhanced apoptosis following exposure to DOX. As a component of a pediatric phase 1 study, we evaluated low-dose DAC with DOX and CTX in a cohort of children with relapsed NBL. Promoter specific DNA methylation in peripheral blood mononuclear cells (PBMC) was studied. Methods: Patients received a 1-hour infusion of DAC, 5 mg/m2, daily on days 0–6, followed on day 7 by 45 mg/m2 of DOX (with dexrazoxane) and 1 g/m2 of CTX. All patients received G-CSF. Cycles were repeated every 28 days. Methylation-specific and quantitative PCR were used to measure promoter-specific DNA methylation in PBMC prior to and after DAC (day 7 and day 28). Results: Twelve patients with recurrent NBL (median age 9 years, 10 males) were enrolled. DAC/DOX/CTX was well tolerated with grade 4 myelosuppression being the predominant toxicity. Grade 4 neutropenia, median 11 days duration, occurred in 10 pts and grade 4 thrombocytopenia, median 10 days, in 7 patients. Eight patients had progressive disease after = 2 courses of therapy. The remaining 4 patients had stable disease with 5 to 8 courses. Methylation and subsequent demethylation (40–90% decreased methylation) of the MAGE-1 promoter was detected before and after DAC respectively, in PBMC from 6 of 9 patients analyzed to date. Re-expression of MAGE-1 mRNA was also demonstrated in post treatment samples. Caspase-8 demethylation was not detected in PBMC; nor was hypermethylation of caspase-8 detected in pre-treatment PBMC, possibly due to low tumor burden in blood. Conclusions: DAC in combination with cytotoxic chemotherapy was relatively well tolerated in heavily pre-treated children with relapsed NBL. Low-dose DAC induces demethylation and re-expression of MAGE-1 in PBMC, and may be a potential surrogate marker of demethylation within tumor cells. The use of low dose DAC in combination with other agents warrants further study in NBL.

No significant financial relationships to disclose.

Pediatric phase I trial and pharmacokinetic (PK) study of dasatinib: A report from the Children’s Oncology Group

14094

Background: Dasatinib is an orally-available tyrosine kinase inhibitor with low-nanomolar activity against SRC-family kinases, BCR-ABL, c-KIT, EPHA2, and the PDGFβ receptor. Methods: A phase I study of dasatinib administered as a single agent in pediatric patients with refractory solid tumors or imatinib refractory Ph+ leukemias is being performed. Dasatinib dose levels of 50, 65, 85 and 110 mg/m2/dose, administered orally twice daily for 28 consecutive days, are being studied. Courses repeat without interruption. Results: 8 pts with solid tumor and 3 pts with Ph+ leukemia (median age 11 yrs, range 7–17) have been enrolled, of whom 7 are fully evaluable for toxicity. At the 50 and 65 mg/m2 dose levels, 0/3 and 0/1 pts experienced DLT. 1 of 3 pts with CML treated at the 50 mg/m2 dose level had Gr 4 hypokalemia. In 4 pts studied at the 50 mg/m2 dose level, the median (range) apparent dasatinib clearance was 238.5 L/hr (220.7 - 332.7), terminal half-life was 2.3 hrs (2.2 - 3.1), and the median Cmax was 55.5 ng/ml (36.0 - 161.1). Conclusions: Dasatinib is well tolerated at a dose of 50 mg/m2 BID on a continuous 28 day dose schedule in pediatric patients. Preliminary PK analysis suggests that drug disposition is similar to that observed in adults. Dose escalation and PK studies are continuing.

No significant financial relationships to disclose.

Characteristics and outcome of patients (pts) enrolled on phase I trials: A report from the Pediatric Oncology Branch, NCI

9550

Background: Knowledge of the characteristics and outcomes of pts enrolled on pediatric phase I trials may aid in the design of future phase I trials and selection of pts. Methods: Pre-enrollment characteristics and treatment outcomes (toxicity, response, survival) were retrospectively analyzed from pts with refractory solid tumors enrolled in 16 phase I trials with similar eligibility criteria from 1992 to 2005. The relationship between patient characteristics and dose-limiting toxicity (DLT) was evaluated using multivariate analysis. Results: Of 262 pts (62% M, 38% F) eligible for analysis, 147 were on trials of myelosuppressive drugs (MS) and 115 were enrolled on trials of non-MS. 50 pts (19%) participated in =2 separate trials. Median (range) or (frequency) entry characteristics were: age 13.5 yrs (1–24); ECOG performance score 0 (30%), 1 (50%), 2 (19%); prior regimens 2 (0–9); prior stem cell transplant (20%); prior radiation (66%); concomitant medications 1 (0–12); and presence of metastatic disease (65%). 94% of pts were evaluable for the primary trial outcome, and 92% participated in pharmacokinetic (PK) studies. 17% of pts had grade 3 as their highest-grade toxicity. 22% of pts had grade 4 as their highest-grade toxicity, of which 91% were hematological. DLT rate was 18%. 5% of pts came off study due to toxicity, and treatment related death occurred in 0.3%. Age, prior radiation, medications, prior regimens, performance status, gender, transplant history, and drug dose expressed as a fraction of the maximum tolerated dose were included in the multivariate analysis. Only drug dose (OR 14.2, 95% CI 3.0–67.8) and prior radiation (OR 3.4, 95% CI 1.1–10.7) were statistically significantly associated with increased risk of developing DLT after adjusting for all other variables. The median number of cycles was 1 (range 0–31). Complete and partial response rate was 3%, however, 18% of pts had stable disease (received = 3 cycles). The median survival (Kaplan Meier analysis) from time of enrollment was 5 months. Conclusion: Standard phase I eligibility criteria selected a population of pts who tolerated the investigational agents well and >90% were evaluable for the toxicity and PK endpoints. Prior radiation was associated with a greater risk for DLT.

No significant financial relationships to disclose.

Determinants of influenza vaccination in hard-to-reach urban populations

OBJECTIVE

Influenza vaccination rates among disadvantaged minority and hard-to-reach populations are lower than in other groups. We assessed the barriers to influenza vaccination in disadvantaged urban areas.

METHODS

We conducted a cross-sectional study, using venue-based sampling, collecting data on residents of eight neighborhoods throughout East Harlem and the Bronx, New York City.

RESULTS

Of 760 total respondents, 461 (61.6%) had received influenza vaccination at some point in their life. In multivariable models, having access to routine medical care, receipt of health or social services, having tested positive for HIV, and current interest in receiving influenza vaccination were significantly associated with having received influenza vaccination in the previous year. Of participants surveyed, 79.6% were interested in receiving an influenza vaccination at the time of survey. Among participants who had never previously received influenza vaccination in the past, 73.4% were interested in being vaccinated; factors significantly associated with an interest in being vaccinated were minority race, lower annual income, history of being homeless, being uninsured/underinsured, and not having access to routine medical care.

CONCLUSIONS

Participants who are unconnected to health or social services or government health insurance are less likely to have been vaccinated in the past although these persons are willing to receive vaccine if it were available.

A phase I study of 17-AAG in relapsed/refractory pediatric patients with solid tumors: A Children’s Oncology Groups study

9018

Background: A pediatric phase I study of 17-allylaminogeldanamycin (17-AAG), an Hsp90 inhibitor, was conducted to determine the dose limiting toxicities (DLTs), the recommended phase II dose, the pharmacokinetics (PK), and to evaluate a surrogate marker for Hsp90 inhibition in peripheral blood mononuclear cells (PBMCs). Methods: Cohorts of 3–6 pts were enrolled at dose levels of 150, 200, 270 and 360 mg/m2/dose, administered as a 60 min infusion, on days 1, 4, 8 and 11 of a 21-day cycle. PK and PBMC evaluations were done during the first course of therapy. Results: 17 pts (7 male), median 7 yrs of age (range 1–19), were enrolled. 5 pts who developed PD prior to completing a full cycle of therapy were not considered evaluable for toxicity. No DLTs occurred. Non-DLTs included elevated transaminases (n=6), anemia (n=3), and vomiting (n=3). Based on the adult recommended dose and challenges posed by infusing the large volumes of DMSO, dose escalation was stopped at dose level 4. No CRs or PRs were observed; 3 patients remain on therapy at 6, 7 and 9 months with SD. One patient with hepatoblastoma had a reduction in AFP and SD over 3 cycles. PK data is available from the initial 3 dose levels. Drug exposure increases in proportion to dose for both17-AAG and its metabolite 17-AG. At 270 mg/m2/dose the Cmax and AUC of 17-AAG were 5,303 ± 1,591 ng/ml and 13,150 ± 5,086 ng/ml*hr, respectively, similar to the exposure in adults. The mean terminal half-life for 17-AAG was 3.0 ± 0.5 hrs. Induction of Hsp72, a surrogate marker for inhibition of Hsp90 was detected at all dose levels. Conclusions: The recommended phase II dose of 17AAG is 360mg/m2/day. Non-DMSO formulations may allow for further dose escalation in children and should be studied.

No significant financial relationships to disclose.

Phase I study of concurrent motexafin gadolinium (MGd) with radiation therapy for children with newly diagnosed brain stem gliomas (BSG): A Children’s Oncology Group study

9014

Background: MGd, a radiosensitizer that selectively accumulates in tumors, generates reactive oxygen species intracellularly. In preclinical experiments, MGd enhances RT-induced apoptosis. Methods: A multi-institutional Phase I dose escalation and pharmacokinetic (PK) study was performed in children with newly diagnosed BSG to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLT) of MGd administered i.v. 2 to 5 hours prior to involved field radiotherapy (RT) (1.8 Gy/day, total 54 Gy). Cohort 1 received MGd, 1.7 mg/kg/dose M-F × 3 wks and cohort 2 received the same dose M, W and F × 6 wks. The 6 subsequent cohorts of 3 to 6 pts received MGd M-F × 6 weeks at doses of 1.9, 3.4, 4.4, 5.5, 7.1 and 9.2 mg/kg/dose. Serum for PK analysis, and MRI scans (MGd is detectable by MR), were obtained for analysis of drug accumulation and responses. Results: 44 pts (42 fully evaluable for toxicity) with a median age of 6 years (range 2–20) were enrolled. At the 9.2 mg/kg/dose, 2/2 pts experienced DLT. During subsequent expansion of the 7.1 and 5.5 mg/kg/dose cohorts, DLTs, including transaminitis, hypertension and urticaria, were observed in 2/5 and 2/6 pts. At the MTD of 4.4 mg/kg/dose, 1/6 pts had reversible grade 3 serum transaminase elevations. PK analysis showed biphasic elimination with a terminal t 1/2 of 6.4 h. At the MTD, serum MGd concentrations were >250 ng/ml for 24 h. Serum clearance and steady-state volume of distribution were 0.0243 L/h/kg and 0.162 L/kg. MRI for intra-tumoral MGd distribution is ongoing. One patient had a CR and 4 had a PR. The estimated median survival is 10.3 months (95% confidence interval: 8.1 months-11.5 months). Conclusions: The recommended phase II dose of MGd for children with BSG is 4.4 mg/kg/d administered M-F × 6 weeks with involved field RT. A COG phase II trial is planned.

[Table: see text]

A pediatric phase I trial and pharmacokinetic (PK) study of erlotinib (ERL) followed by the combination of ERL with temozolomide (TMZ): A Children’s Oncology Group Study

9015

Background: EGFR is potently inhibited by ERL. Aberrant cell signaling via the EGFR family has been implicated in the development of several human cancers, including certain pediatric solid tumors. Methods: A phase I dose escalation study in children with refractory solid tumors was conducted to define the maximal tolerated dose (MTD) and dose limiting toxicities (DLTs) of single agent ERL, determine the tolerability of the combination of ERL and TMZ, and to determine the PK of ERL. Pts received single agent ERL qd × 28 d followed by ERL qd continuously in combination with TMZ 180 mg/m2/day × 5d. Cycles were repeated q 28 d. ERL was initially administered using the IV formulation given orally. The tablet form was subsequently studied at the MTD to further evaluate PK. Results: 46 pts (36 fully evaluable for toxicity) median age 11.5 yrs (range 3–20 yrs), were enrolled in cohorts of 3–6 pts at ERL doses of 35, 50, 65, 85 and 110 mg/m2/d. At the 110 mg/m2/day dose level, 2/4 pts had DLT (1 rash, 1 hyperbilirubinemia). In the expanded cohort at the MTD of 85 mg/m2/d, (n=21), 3 pts had DLT (2 rash, 1 diarrhea). Non-DLTs observed during the single agent cycle included diarrhea (n=14), rash (n=9), hyperbilirubinemia (n=7), neutropenia and/or thrombocytopenia (n=5). 1 pt with a soft tissue sarcoma had a minor response after 28d of single agent ERL, continuing to a PR by cycle 4. 3 pts (2 neuroblastoma, 1 neurocytoma) had prolonged responses (13–20+ months) to the combination. Oral administration of the IV formulation resulted in a higher Cmax and a lower Cmin compared to the adult data using tablets. Median apparent clearance was 2.85 (range 1.61–6.37) L/hr/m2 with a terminal half of 8.45 (5.1–27.1) hr. No PK interaction was observed between ERL and TMZ and the combination was well tolerated. Conclusions: The pediatric recommended phase 2 dose of ERL of 85 mg/m2/day, either alone or in combination with TMZ, is well tolerated in children. A COG phase 2 trial is planned.

[Table: see text]

Efficacy and safety of rasburicase, a recombinant urate oxidase (Elitek), in the management of malignancy-associated hyperuricemia in pediatric and adult patients: final results of a multicenter compassionate use trial

The recombinant urate oxidase, rasburicase (Elitek, Sanofi-Synthelabo, Inc.), has recently received regulatory approval for the prevention and treatment of hyperuricemia in children with leukemia, lymphoma, and solid tumors. Prior to approval, 682 children and 387 adults in the US and Canada received rasburicase on compassionate-use basis. Uric acid concentration declined rapidly in both adult and pediatric patients after rasburicase treatment. Similar responses were observed in patients treated with subsequent courses. Possible drug-related adverse events, including allergic reactions, were uncommon. These data confirm that rasburicase is effective and safe for the treatment and prophylaxis of children and adults with malignancy-associated hyperuricemia.

Ubiquitin-proteasome-dependent proteolysis in rainbow trout (Oncorhynchus mykiss): effect of food deprivation

The ubiquitin-proteasome proteolytic pathway is a major route of protein degradation and of particular importance in muscle proteolysis in mammals. In this study, the beta proteasome subunit N3 and polyubiquitin genes of the rainbow trout, Oncorhynchus mykiss, were sequenced and tissue distribution of gene expression was examined. The effects of 14-day food withdrawal were assessed on the N3 subunit and polyubiquitin gene expression in terms of mRNA, 20S proteasome proteolytic activity and ubiquitin protein abundance in trout liver and muscle. Both sequences are highly conserved, and the rainbow trout ubiquitin amino acid sequence is identical to the mammalian protein. The proteasome beta subunit N3 has 92% similarity to the Xenopus sequence. Starvation halved the polyubiquitin mRNA level in liver but had no effect on muscle levels. No significant effect of food withdrawal was observed on the proteasome mRNA in liver or muscle. Food withdrawal decreased the 20S proteasome proteolytic activity and the abundance of ubiquitin protein in both muscle and liver. Co-regulation of the proteasome and ubiquitin was indicated by the high correlation ( R=0.924) between 20S activity and ubiquitin abundance. Overall, this study demonstrates that starvation down-regulates the ubiquitin-proteasome pathway, possibly highlighting differences in the regulation of protein turnover in poikilothermic and endothermic animals.

Meropenem pharmacokinetics in children and adolescents receiving hemodialysis

The emergence of multi-drug-resistant bacteria is of great concern to the care of pediatric end-stage renal disease (ESRD) patients who receive either hemodialysis or peritoneal dialysis via a catheter. Infections with gram-negative organisms, especially Pseudomonas aeruginosa, are difficult to eradicate and often necessitate catheter removal. Meropenem, a broad-spectrum antibiotic of the carbapenem class of beta-lactams, is effective against most gram-positive and gram-negative bacteria and has enhanced activity against P. aeruginosa. We studied the pharmacokinetics of meropenem during and between hemodialysis treatments in seven pediatric patients. Meropenem was given as a single dose of 20 mg/kg (maximum 500 mg) before and after two separate hemodialysis treatments. Meropenem administration was tolerated without any adverse effects. Hemodialysis effectively cleared meropenem in a manner that correlated with percent urea reduction. Median drug half-life was 7.3 h off dialysis (range 4.9-11.7 h). The dose of 20 mg/kg was not sufficient to produce an acceptable interdialytic pharmacodynamic profile of 70% duration with a meropenem concentration >4 microg/ml, the MIC90 of meropenem for P. aeruginosa. Dosing simulations revealed that a daily dose of 25 mg/kg or an alternate day dose of 40 mg/kg would result in an acceptable pharmacodynamic profile. Both simulated doses achieved acceptable peak concentrations.

Plasma and cerebrospinal fluid pharmacokinetics of gemcitabine after intravenous administration in nonhuman primates

PURPOSE

Gemcitabine (dFdC) is a difluorine-substituted deoxycytidine analogue that has demonstrated antitumor activity against both leukemias and solid tumors. Pharmacokinetic studies of gemcitabine have been performed in both adults and children but to date there have been no detailed studies of its penetration into cerebrospinal fluid (CSF). The current study was performed in nonhuman primates to determine the plasma and CSF pharmacokinetics of gemcitabine and its inactive metabolite, difluorodeoxyuridine (dFdU) following i.v. administration.

METHODS

Gemcitabine, 200 mg/kg, was administered i.v. over 45 min to four nonhuman primates. Serial plasma and CSF samples were obtained prior to, during, and after completion of the infusion for determination of gemcitabine and dFdU concentrations. Gemcitabine and dFdU concentrations were measured using high-performance liquid chromatography (HPLC) and modeled with model-dependent and model-independent methods.

RESULTS

Plasma elimination was rapid with a mean t1/2 of 8 +/- 4 min (mean +/- SD) for gemcitabine and 83 +/- 8 min for dFdU. Gemcitabine total body clearance (ClTB) was 177 +/- 40 ml/min per kg and the Vdss was 5.5 +/- 1.0 l/kg. The maximum concentrations (Cmax) and areas under the time concentration curves (AUC) for gemcitabine and dFdU in plasma were 194 +/- 64 microM and 63.8 +/- 14.6 microM.h, and 783 +/- 99 microM and 1725 +/- 186 microM.h, respectively. The peak CSF concentrations of gemcitabine and dFdU were 2.5 +/- 1.4 microM and 32 +/- 41 microM, respectively. The mean CSF:plasma ratio was 6.7% for gemcitabine and 23.8% for dFdU.

CONCLUSIONS

There is only modest penetration of gemcitabine into the CSF after i.v. administration. The relatively low CSF exposure to gemcitabine after i.v. administration suggests that systemic administration of this agent is not optimal for the treatment of overt leptomeningeal disease. However, the clinical spectrum of antitumor activity and lack of neurotoxicity after systemic administration of gemcitabine make this agent an excellent candidate for further studies to assess the safety and feasibility of intrathecal administration.

Pharmacokinetics and cerebrospinal fluid penetration of phenylacetate and phenylbutyrate in the nonhuman primate

INTRODUCTION

Phenylbutyrate (PB) and its metabolite phenylacetate (PA) demonstrate anticancer activity in vitro through promotion of cell differentiation, induction of apoptosis through the p21 pathway, inhibition of histone deacetylase, and in the case of PB, direct cytotoxicity. We studied the pharmacokinetics, metabolism, and cerebrospinal fluid (CSF) penetration of PA and PB after intravenous (i.v.) administration in the nonhuman primate.

METHODS

Three animals received 85 mg/kg PA and 130 mg/kg PB as a 30-min infusion. Blood and CSF samples were obtained at 15, 30, 35, 45, 60 or 75 min, and at 1.5, 2.5, 3.5, 5.5, 6.5, 8.5, 10.5 and 24.5 h after the start of the infusion. Plasma was separated immediately, and plasma and CSF were frozen until HPLC analysis was performed.

RESULTS

After i.v. PA administration, the plasma area under the concentration-time curve (AUC) of PA (median +/- SD) was 82 +/- 16 mg/ml.min, the CSF AUC was 24 +/- 7 mg/ml.min, clearance (Cl) was 1 +/- 0.3 ml/min per kg, and the AUCCSF:AUCplasma ratio was 28 +/- 19%. After i.v. PB administration, the plasma PB AUC was 19 +/- 3 mg/ml.min, the CSF PB AUC was 8 +/- 11 mg/ml.min, the PB Cl was 7 +/- 1 ml/min per kg, and the AUCCSF:AUCplasma ratio was 41 +/- 47%. The PA plasma AUC after i.v. PB administration was 50 +/- 9 mg/ml.min, the CSF AUC was 31 +/- 24 mg/ml.min, and the AUCCSF:AUCplasma ratio was 53 +/- 46%.

CONCLUSIONS

These data indicate that PA and PB penetrate well into the CSF after i.v. administration. There may be an advantage to administration of PB over PA, since the administration of PB results in significant exposure to both active compounds. Clinical trials to evaluate the activity of PA and PB in pediatric central nervous system tumors are in progress.

A phase I study of irinotecan in pediatric patients: a pediatric oncology group study

A Phase I trial of irinotecan was performed to determine the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), and the incidence and severity of other toxicities in children with refractory solid tumors. Thirty-five children received 146 courses of irinotecan administered as a 60-min i.v. infusion, daily for 5 days, every 21 days, after premedication with dexamethasone and ondansetron. Doses ranged from 30 mg/m2 to 65 mg/m2. An MTD was defined in heavily pretreated and less-heavily pretreated (i.e., two prior chemotherapy regimens, no prior bone marrow transplantation, and no radiation to the spine, skull, ribs, or pelvic bones) patients. Myelosuppression was the primary DLT in heavily pretreated patients, and diarrhea was the DLT in less-heavily pretreated patients. The MTD in the heavily pretreated patient group was 39 mg/m2, and the MTD in the less-heavily pretreated patients was 50 mg/m2. Non-dose-limiting diarrhea that was well controlled and of brief duration was observed in approximately 75% of patients. A partial response was observed in one patient with neuroblastoma, and in one patient with hepatocellular carcinoma. Stable disease (4-20 cycles) was observed in seven patients with a variety of malignancies including neuroblastoma, pineoblastoma, glioblastoma, brainstem glioma, osteosarcoma, hepatoblastoma, and a central nervous system rhabdoid tumor. In conclusion, the recommended Phase II dose of irinotecan administered as a 60-min i.v. infusion daily for 5 days, every 21 days, is 39 mg/m2 in heavily treated and 50 mg/m2 in less-heavily treated children with solid tumors.

Phase I and pharmacokinetic study of CI-980 in recurrent pediatric solid tumor cases: a Pediatric Oncology Group study

To establish the maximum tolerated dosage (MTD), the dose-limiting toxicities (DLTs), and pharmacokinetic parameters of CI-980, a novel tubulin binder, in children with solid tumors refractory to standard therapy. Patients 21 years of age or younger with adequate nutritional, hematopoietic, renal, and hepatic function were eligible. The patient must not have been pregnant. Patients with brain tumors were not eligible for any dosage level until it was demonstrated the level did not produce DLT in patients with extracranial solid tumors. The starting dosage level was 3.5 mg/m2/day, for 3 days, administered as a continuous intravenous infusion (80% of the adult MTD). If a dosage level was associated with dose-limiting myelotoxicity, growth factors were to be added. Thirty-three patients received CI-980. Twenty-four had solid tumor; 9 had brain tumor. The MTD achieved without granulocyte colony stimulating factor (G-CSF) was 3.5 mg/m2/day (DLT: neutropenia) and with G-CSF, it was as follows: patients with brain tumor, 4.2 mg/m2/day (DLT: myelosupression); and patients with solid tumor, 5 mg/m2/day (DLT: cortical toxicity). Several responses were seen, most notably prolonged stable disease in two of five patients with medulloblastoma. Pharmacokinetic data showed a mean steady state level of 1.74 ng/mL for two patients treated with the 5 mg/m2/day regimen, with rapid decay after the termination of the infusion. CI-980 showed preliminary evidence of activity in recurrent pediatric malignancies, with tolerable, reversible toxicities.

Phase I trial of 9-aminocamptothecin in children with refractory solid tumors: a Pediatric Oncology Group study

PURPOSE

A phase I trial of 9-aminocamptothecin (9-AC) was performed in children with solid tumors to establish the dose-limiting toxicity (DLT), maximum-tolerated dose (MTD), and the pharmacokinetic profile in children and to document any evidence of activity.

PATIENTS AND METHODS

A 72-hour infusion of 9-AC dimethylacetamide formulation was administered every 21 days to 23 patients younger than 21 years of age with malignant tumors refractory to conventional therapy. Doses ranged from 36 to 62 microg/m2 per hour. Pharmacokinetics were to be performed in at least three patients per dose level. The first course was used to determine the DLT and MTD.

RESULTS

Nineteen patients on four dose levels were assessable for toxicities. At 62 microg/m2 per hour, three patients experienced dose-limiting neutropenia and one patient experienced dose-limiting thrombocytopenia. Pharmacokinetics were performed on 15 patients (nine patients had complete sets of plasma sampling performed). The pharmacokinetics of both lactone and total 9-AC were highly variable. The percentage of 9-AC lactone at steady-state was 10.8% +/- 3.6%. Total 9-AC and its lactone form had a terminal half-life of 8.1 +/- 3.8 and 7.1 +/- 3.9 hours, respectively, and a volume of distribution at steady-state (Vdss) of 21.2 +/- 13.3 L/m2 and 135.3 +/- 52.5 L/m2, respectively. Hepatic metabolism and biliary transport had an important role in 9-AC disposition.

CONCLUSION

The recommended phase II dose of 9-AC administered as a 72-hour infusion every 21 days to children with solid tumors is 52 microg/m2 per hour. Neutropenia and thrombocytopenia were dose limiting.

Clear cell sarcoma of the kidney: an unusual presentation and review of the literature

PURPOSE

To describe a child with clear cell sarcoma of the kidney (CCSK) with an unusual presentation, including a primary tumor of the left kidney with metastases to the right kidney and soft tissues of the lower extremities, and to review the literature.

PATIENT AND METHODS

An 8-month-old infant presented with hypertension, an abdominal mass, and soft tissue masses in the left thigh and right foot. Imaging studies revealed a large left-sided renal tumor, left paravertebral soft tissue masses, and left thigh mass. At laparotomy, a lesion was noted in the lower pole of the contralateral kidney. CCSK with metastases to the contralateral kidney and to the soft tissues of left thigh, right foot, and left paravertebral region was diagnosed on histopathologic examination.

RESULTS

Multimodal oncologic treatment included surgery, chemotherapy, and radiotherapy. Three months after completion of therapy, a soft tissue lesion in the left arm and, later, soft tissue lesions involving multiple parts of the body developed. The patient died 18 months after diagnosis without clinical or radiographic evidence of bone involvement.

CONCLUSIONS

In a review of the literature, CCSK is most commonly associated with bone and lung metastases. Soft tissue involvement is uncommon. Metastasis to the contralateral kidney at initial diagnosis has not previously been reported. This case represents an unusual metastatic pattern of CCSK.

A prospective evaluation of ifosfamide-related nephrotoxicity in children and young adults

BACKGROUND

Ifosfamide has been associated with proximal renal tubular dysfunction resembling Fanconi-like syndrome and leading to rickets in young children. The characteristic manifestations of this nephrotoxicity include phosphaturia and hypophosphatemia, glycosuria, aminoaciduria, renal tubular acidosis, and urinary loss of low molecular weight serum proteins. However, the relationship between acute ifosfamide nephrotoxicity, which is frequently subclinical, and long term renal damage is unclear. In this prospective study, the laboratory features of ifosfamide-induced acute nephrotoxicity were characterized further and correlated with the development of chronic nephropathy.

METHODS

The renal function of newly diagnosed children and young adults with high risk sarcomas was followed during therapy with a high dose ifosfamide-containing regimen. Serum and urine were collected regularly immediately before and after 5-day cycles of ifosfamide throughout treatment for determination of the fractional excretion of electrolytes (sodium, potassium, phosphate, magnesium, calcium) and glucose and urinary excretion of amino acids and beta 2-microglobulin.

RESULTS

Significant changes in the renal threshold of phosphate excretion, the fractional excretion of calcium and glucose, and the urinary excretion of beta 2-microglobulin were observed when comparing pretreatment values with those at the end of a 5-day treatment cycle. The median renal threshold of phosphate excretion decreased from 1.22 to 0.82 mmol/L (P < 0.0001). The median fractional excretions of calcium and glucose increased from 1.05% to 1.68% (P < 0.0001) and 0.05% to 0.08% (P = 0.0006), respectively. Beta 2-microglobulin excretion increased by 70-fold from 0.02 to 1.42 mg/mmol (P < 0.0001). Except for glucose and beta 2-microglobulin excretion, renal parameters returned to baseline before the next ifosfamide treatment cycle. Acute aminoaciduria was observed in 21 of 23 patients. Chronic nephrotoxicity, as defined by the development of a Fanconi-like syndrome or chronic tubular electrolyte loss requiring oral supplementation, developed in the three patients with the highest urinary excretion of beta 2-microglobulin after ifosfamide therapy.

CONCLUSIONS

Prospectively, high dose ifosfamide was associated with a 4% incidence of Fanconi-like syndrome; however, evidence of acute reversible subclinical nephrotoxicity was observed for all patients. Severe beta 2-microglobulinuria appeared to be a prognostic laboratory indicator for the development of chronic nephrotoxicity.