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Mark Bernstein

Publications and source records attributed to Mark Bernstein.

68 records · Page 4Linked to original sources
PubMed2003

Framework for bioethical assessment of an article on therapy.

OBJECT: Frameworks for scientific assessment of articles on therapy published in the medical literature have become available and will likely enhance the quality of medical research that is published in peer-reviewed journals. Comprehensive frameworks do not exist for the assessment of bioethical issues pertaining to research on human volunteers. METHODS: The authors have developed a framework consisting of ethical dimensions or questions that they suggest should be applied to assess the bioethical integrity of articles on therapy. Thirteen questions were developed and discussed in the context of current bioethical principles, and examples were applied where possible. CONCLUSIONS: The simple framework the authors have developed offers a method to assess key bioethical issues surrounding an article on therapy and probably defines the minimum standard to which such articles should be held. Many ethical questions cannot yet be answered based on available information or bioethical theories. The authors are not suggesting that their framework is comprehensive; refinements and individualization of it to fit specific studies are probably required by each clinician-researcher who designs a therapy trial and reports its results.

Bioethical Issues↗
PubMed2003

Perioperative complications and neurological outcomes of first and second craniotomies among patients enrolled in the Glioma Outcome Project.

OBJECT: In many new clinical trials of patients with malignant gliomas surgical intervention is incorporated as an integral part of tumor-directed interstitial therapies such as gene therapy, biodegradable wafer placement, and immunotherapy. Assessment of toxicity is a major component of evaluating these novel therapeutic interventions, but this must be done in light of known complication rates of craniotomy for tumor resection. Factors predicting neurological outcome would also be helpful for patient selection for surgically based clinical trials. METHODS: The Glioma Outcome Project is a prospectively compiled database containing information on 788 patients with malignant gliomas that captured clinical practice patterns and patient outcomes. Patients in this series who underwent their first or second craniotomy were analyzed separately for presenting symptoms, tumor and patient characteristics, and perioperative complications. Preoperative and intraoperative factors possibly related to neurological outcome were evaluated. There were 408 patients who underwent first craniotomies (C1 group) and 91 patients who underwent second ones (C2 group). Both groups had similar patient and tumor characteristics except for their median age (55 years in the C1 group compared with 50 years in the C2 group; p = 0.006). Headache was more common at presentation in the C1 group, whereas papilledema and an altered level of consciousness were more common at presentation in patients undergoing second surgeries. Perioperative complications occurred in 24% of patients in the C1 group and 33% of patients in the C2 group (p = 0.1). Most patients were the same or better neurologically after surgery, but more patients in the C2 group (18%) displayed a worsened neurological status than those in the C1 group (8%; p = 0.007). The Karnofsky Performance Scale score and, in patients in the C2 group, tumor size were important neurological outcome predictors. Regional complications occurred at similar rates in both groups. Systemic infections occurred more frequently in the C2 group (4.4 compared with 0%; p < 0.0001) as did depression (20 compared with 11%; p = 0.02). The perioperative mortality rate was 1.5% for the C1 group and 2.2% for the C2 group (p = not significant). The median length of the hospital stay was 4 days in each group. CONCLUSIONS: Perioperative complications occur slightly more often following a second craniotomy for malignant glioma than after the first craniotomy. This should be considered when evaluating toxicities from intraoperative local therapies requiring craniotomy. Nevertheless, most patients are neurologically stable or improved after either their first or second craniotomy. This data set may serve as a benchmark for neurosurgeons and others in a discussion of operative risks in patients with malignant gliomas.

Central Nervous System Neoplasms↗
PubMed2003

Survival following surgery and prognostic factors for recently diagnosed malignant glioma: data from the Glioma Outcomes Project.

OBJECT: The Glioma Outcomes Project represents a contemporary analysis of the management of malignant (Grade III and Grade IV/GBM) gliomas in North America. This observational database was used to evaluate the influence of resection, as opposed to biopsy, on patient outcome as measured by the length of survival. Attempts were made to reduce the impact of selection bias by repeating the data analysis after omitting patients with major negative prognostic factors. METHODS: Outcome data from 788 patients accrued from multiple sites over a 4-year period (1997-2001) were analyzed with the primary outcome measure being length of survival. Of these, 565 patients with recent diagnoses formed the basis of the present analysis. Patients were systematically followed up until death or up to 24 months after enrollment in the study, and survival data were correlated with the histopathological grade and location of the tumor, the extent of surgery, the patient's performance status, and demographic factors. The median length of survival was 40.9 weeks for patients with recently diagnosed GBMs. The true median length of survival for patients with Grade III gliomas was not reached, although there was a 58% survival rate at 104 weeks. In multivariate analysis, resection rather than biopsy (p < 0.0001), age 60 years or younger (p < 0.0001), and a Karnofsky Performance Scale (KPS) score of 70 or greater (p = 0.0004) were associated with a prolonged survival time for patients with Grade III or IV gliomas. The prognostic value of resection compared with biopsy was maintained (p < 0.0001), even after eliminating patients considered to be "poor risk" (those with age > 60 years, KPS score < 70, or presence of multifocal tumors), who may have been overrepresented in the biopsy group. Survival "tails" at 24 months were 58% for Grade III gliomas and 11% for GBMs. CONCLUSIONS: These data provide Class II evidence to support tumor grade, patient's age, and patient's functional status as prognostic factors for survival in individuals with recently diagnosed malignant gliomas. Resection (compared with biopsy) is also a strong prognostic factor; however, no quantitative attempt was made to assess the true extent of the resection.

Adult↗
PubMed2003

Sequence alterations in the reduced folate carrier are observed in osteosarcoma tumor samples.

High-dose methotrexate is a standard component of therapy for high-grade osteosarcoma. Its effectiveness may be limited by intrinsic and acquired resistance. Decreased reduced folate carrier (RFC) expression has been shown in approximately half of osteosarcomas at diagnosis. Mutations and polymorphisms in the RFC gene have been reported in various cell lines. The purpose of this study was to investigate sequence alterations in the RFC gene in osteosarcoma tumor samples. The entire coding region of the RFC gene in samples from 162 osteosarcoma patients was screened by DNA single-stranded conformational polymorphism, followed by direct sequencing of any region with altered mobility. A previously identified polymorphism at cDNA position number 174 of RFC exon 2 was observed. Sixty-one samples (37.6%) were heterozygous with both A/G at this position (His(27)/Arg(27)), 52 samples (32.2%) were homozygous with G (Arg(27)), and 49 samples (30.2%) were homozygous with A (His(27)). Fifteen (9.2%) samples were identified with other RFC sequence variants in exon 2, none of which have been reported. The sequence variants in exon 2 included a G to A substitution at cDNA position 231, a G to A substitution at cDNA position 155, a C to T substitution at cDNA position 114, and a T to C substitution at cDNA position 104, resulting in a serine to asparagine substitution at amino acid 46, a glutamate to lysine substitution at amino acid 21, an alanine to valine substitution at amino acid 7, and a serine to proline substitution at amino acid 4, respectively. A deletion of A at cDNA position 126 resulting in a frameshift was also observed. Some of these variants were observed in multiple samples. Eight samples had altered single-stranded conformational polymorphism patterns in exon 3 that were associated with nucleotide changes that altered the amino acid sequence. All of these RFC sequence variants appeared to be heterozygous. Heterozygous C/T and homozygous C also were observed at RFC cDNA position 790 in exon 3, which does not alter the amino acid coding sequence. This study shows that RFC sequence alterations are frequent in samples from osteosarcoma patients. Additional studies are under way to determine the clinical significance of these sequence alterations and their effect on methotrexate transport and resistance.

Amino Acid Sequence↗
PubMed2002

Screening of infants and mortality due to neuroblastoma.

BACKGROUND: Neuroblastoma, the most common extracranial solid tumor that occurs in early childhood, can be identified in the preclinical stages by the detection of catecholamines in the urine. However, it is unknown whether routine screening for neuroblastoma reduces mortality due to this disease. METHODS: Through their parents, we offered screening for neuroblastoma at three weeks and six months of age to all 476,654 children born in the province of Quebec, Canada, during a five-year period (May 1, 1989, through April 30, 1994). The participation rate was 92 percent. The rate of death due to neuroblastoma was determined and compared with the rates in several unscreened control populations born during the same period. RESULTS: Among children younger than eight years of age in the Quebec cohort, there were 22 deaths due to neuroblastoma; the cumulative (+/-SE) mortality rate due to neuroblastoma was 4.78+/-1.14 per 100,000 children over a period of nine years. The standardized incidence ratios for death due to neuroblastoma for the Quebec cohort were 1.11 (95 percent confidence interval, 0.64 to 1.92) as compared with a control group in Ontario, Canada; 0.90 (95 percent confidence interval, 0.48 to 1.70) as compared with a control group in Minnesota; 1.40 (95 percent confidence interval, 0.81 to 2.41) as compared with a control group in Florida; and 0.96 (95 percent confidence interval, 0.56 to 1.66) as compared with a control group in the Greater Delaware Valley. The standardized mortality ratio for the Quebec cohort as compared with the rest of Canada was 1.39 (95 percent confidence interval, 0.85 to 2.30); the odds ratio for the comparison with a cohort born in Quebec before the screening program began was 0.98 (95 percent confidence interval, 0.54 to 1.77). CONCLUSIONS: Screening infants for neuroblastoma does not appear to reduce mortality due to this disease.

Canada↗
PubMed2002

Phase II/III trial of etoposide and high-dose ifosfamide in newly diagnosed metastatic osteosarcoma: a pediatric oncology group trial.

PURPOSE: The objectives of this trial were to estimate the response rate, progression-free survival, and overall survival of patients who received therapy with etoposide and high-dose ifosfamide, and to define the toxicity of this combination when provided with standard chemotherapy in patients with newly diagnosed metastatic osteosarcoma. PATIENTS AND METHODS: Eligible patients received infusions of 100 mg/m(2) per day of etoposide and 3.5 g/m(2) per day of ifosfamide for 5 days. Therapy with granulocyte colony-stimulating factor was begun on day 6. This was repeated 3 weeks after therapy was begun. Response was determined at week 6 by both standard World Health Organization response criteria and by pathologic determination of tumor necrosis of the primary tumor. RESULTS: Forty-three patients were registered; 39 were assessable for response and 41 for toxicity and survival. Twenty-eight (68%) of 41 had metastatic sites only in the lung; 12 (29%) had metastatic sites in other bones with or without lung involvement. Four patients (10%) experienced complete response, and 19 patients (49%) experienced partial response, for an overall response rate of 59% +/- 8%. The projected 2-year progression-free survival (PFS) for the 28 patients with metastases to lungs was 39% +/- 11%. The projected 2-year PFS for the 12 patients with metastases to other bones (with or without pulmonary metastases) was 58% +/- 17%. Two patients died as a result of therapy toxicity. Eighty-three percent of patients had grade 4 neutropenia, and 29% had grade 4 thrombocytopenia. Ten patients (24%) had sepsis. Fanconi's syndrome was observed in five patients. CONCLUSION: The combination of etoposide and high-dose ifosfamide is effective induction chemotherapy for patients with metastatic osteosarcoma, despite significant associated myelosuppression sometimes complicated by infection and renal toxicity.

Adolescent↗
PubMed2002

Outpatient lumbar microdiscectomy: a prospective study in 122 patients.

BACKGROUND: Outpatient surgery saves the risk of nosocomial complications and health care dollars. Patients undergoing lumbar microsurgical discectomy are excellent candidates for outpatient surgery. The object of this study was to examine the feasibility of performing lumbar microdiscectomy on an outpatient protocol and to examine the potential savings associated with such a protocol. METHODS: From February 1997 to September, 2001, 122 consecutive patients of the senior author were entered into a protocol of outpatient lumbar microdiscectomy. Only elective cases were considered for this study. Patients were excluded if they had significant co-morbidities, lived a significant distance out of town, or if their surgery was scheduled too late in the day. Success was defined as discharge home from the day-surgery unit approximately four hours after surgery. RESULTS: During the study period, 150 elective lumbar microdiscectomies were performed. Twenty-four patients were excluded based on the above criteria and four patients requested not to participate in the study. Of the remaining 122, 116 successfully completed the protocol (95.1%). Six patients were admitted from the day surgery unit; two patients with dural tears and four patients with anaesthetic side-effects. No patient was readmitted to hospital after discharge and no complications of early discharge were observed. There was a total reduction in hospitalization of 1.2 nights per elective procedure considering the 150 patients, when compared with the hospitalization times prior to outpatient lumbar microdiscectomy. CONCLUSIONS: Lumbar microdiscectomy can be performed safely as an outpatient procedure, resulting in a substantial reduction in hospitalization times.

Adult↗
PubMed2002

Influence of phenytoin on the disposition of irinotecan: a case report.

Irinotecan (CPT-11), a water-soluble topoisomerase I inhibitor, is metabolized by carboxylesterase enzymes to form an active metabolite, SN-38. Recent studies have shown that irinotecan also undergoes oxidative metabolism by the P450 isozyme CYP3A4, leading to the formation of a minor inactive metabolite, 7-ethyl-10-[4-N-[(5-aminopentanoic acid)-1-piperidino]-carbonyloxy-camptothecin (APC). The elucidation of this metabolic pathway suggests the potential for drug interactions when irinotecan is administered with other inducers or substrates of CYP3A4. In this report, the authors summarize the pharmacokinetic profile of irinotecan and its major metabolites with and without concomitant phenytoin administration in an individual patient. These studies revealed that concomitant phenytoin administration resulted in a marked decrease in the systemic exposure to irinotecan and SN-38 and an increase in the exposure to APC. The area under the curve of irinotecan and SN-38 decreased by 63% and 60%, respectively; the area under the curve of APC increased by approximately 16%. Further detailed pharmacokinetic studies of irinotecan in patients receiving concomitant therapy with enzyme-inducing anticonvulsants are required so that rational dosing recommendations can be provided for this patient population.

Adolescent↗
PubMed2002

House of healing, house of disrespect: a Kantian perspective on disrespectful behaviour among hospital workers.

Respect toward patients is one of the most fundamental and central tenets guiding both modern bioethical practice and the everyday behaviour of all healthcare professionals. However, similar courtesy and respect is often breached in day-to-day interactions between hospital workers. Many examples are relatively minor, while egregious examples such as gender discrimination and physical abuse do occur. The more egregious transgressions may be handled by formal processes, even legal proceedings. However, the innumerable smaller examples of disrespectful behaviour are ubiquitous and insidious in their erosion of a productive collaborative approach to patient care and other aspects of functioning within the institution. The authors briefly summarize some of the pertinent literature on this subject and analyze the problem of disrespect in the hospital with special focus on the issue as seen from the perspective of the moral philosophy of Immanuel Kant. Some simple recommendations for improving disrespectful behaviour amongst hospital workers are offered.

Agonistic Behavior↗
PubMed2002

Dose escalation and pharmacokinetics of pegylated liposomal doxorubicin (Doxil) in children with solid tumors: a pediatric oncology group study.

PURPOSE: To determine the maximum tolerated dose and pharmacokinetics of Doxil in children with recurrent or refractory solid tumors. Doxil is pegylated doxorubicin. EXPERIMENTAL DESIGN: Eligible patients were children with refractory tumors who had received cumulative anthracycline doses <300 mg/m(2). Cohorts of at least three patients each received escalating doses of Doxil starting at 40 mg/m(2) at 4-week intervals. If no dose-limiting toxicity occurred, dosages were escalated by increments of 10 mg/m(2) in subsequent cohorts. Originally, Doxil was administered over 60 min, but significant infusion reactions prompted longer infusion times of 4 h. Patients also received premedication with dexamethasone, ranitidine, and diphenhydramine 24 h before infusion, with ranitidine continued 24 h after infusion. Periodic blood samples were collected and plasma doxorubicin concentrations were quantified to characterize the pharmacokinetics of Doxil. RESULTS: Between January 1997 and June 2000, 22 children ages 4-21 years with refractory tumors were treated with Doxil. Most patients had received one to five prior chemotherapy regimens, and all but five had prior radiotherapy (two had no prior therapy). Doxil was escalated to a dosage of 70 mg/m(2). At that level, dose-limiting mucositis was seen during the first cycle in two of six patients, thus defining dose-limiting toxicity, and in one additional patient during a subsequent cycle. Grade 4 neutropenia lasting less than 7 days was documented in two of six patients. The dose-limiting toxicity among two of six patients at 70 mg/m(2) was grade 3 mucositis during the first cycle of therapy. Painful desquamating dermatitis of the hands and feet, palmar-plantar erythrodysesthesia, occurred in six patients. In two of those patients, palmar-plantar erythrodysesthesia started as grade 1 and progressed to grade 2 during subsequent courses. Mean estimates of central volume of distribution, clearance, and elimination half-life were 1.45 liters/m(2), 0.03 liter/h/m(2), and 36.4 h, respectively. CONCLUSION: The maximum tolerated dose of Doxil administered every 4 weeks to pediatric patients was 60 mg/m(2). The effect of Doxil on pediatric patients with malignancies remains to be determined and should be studied in pediatric Phase II trials.

Adolescent↗
PubMed2002

Prospective feasibility study of outpatient stereotactic brain lesion biopsy.

OBJECTIVE: To assess the safety and feasibility of performing computed tomography-guided stereotactic brain lesion biopsy as an outpatient day-surgery procedure. METHODS: In late 1996, a prospective trial of outpatient stereotactic biopsies was initiated. The protocol consists of preadmission education of the patient, computed tomography-guided biopsy with local anesthesia (using a Brown-Roberts-Wells or Cosman-Roberts-Wells frame), postoperative observation in the postanesthetic care unit for 2 hours and in the day surgery unit for 2 hours, and then discharge home 4 hours after the procedure. RESULTS: Seventy-six patients constituted the intent-to-treat group, of whom two were not discharged on the same day (97.4% success rate). The two patients underwent inpatient admission because one required intravenous antibiotic treatment of a brain abscess and the other had a hard lesion in the brainstem that precluded biopsy needle penetration; admission for further investigation of the lesion was elected. Two patients experienced complications (2.6%), i.e., one small area of intraventricular hemorrhage that produced only a mild headache and one case of mild worsening of preexisting leg weakness, with negative computed tomographic results. CONCLUSION: Discharging patients home after 4 hours of observation after stereotactic biopsies seems to be a safe, well-tolerated practice. In this series, there was no major morbidity and no patient was disadvantaged by participating in this protocol. This approach would be expected to result in health care resource and cost savings, with a potential increase in patient satisfaction because of shorter hospital stays.

Adult↗
PubMedDate not supplied

Activation of expression of p15, p73 and E-cadherin in leukemic cells by different concentrations of 5-aza-2'-deoxycytidine (Decitabine).

BACKGROUND: Inactivation of genes that suppress neoplasia by aberrant DNA methylation is a key event that occurs during the development of leukemia. The inhibitor of DNA methylation, 5-aza-2'-deoxycytidine (5AZA), which can re-activate these genes, is under clinical investigation for therapy of leukemia. The objective of this study was to determine the concentrations of 5AZA that will re-activate target silent genes in human leukemic cell lines. MATERIALS AND METHODS: RT-PCR was used to evaluate the effect of concentrations of 1 to 100 ng/ml of 5AZA on the re-activation of p15 and p73 in KG1a myeloid leukemic cells and E-cadherin in HL-60 myeloid leukemic cells. The effect of 5AZA on inhibition of growth, DNA synthesis and colony formation in these cell lines was also investigated. RESULTS: The extent of activation of the target genes was dependent on the concentration of 5AZA. For p15, pronounced activation was observed at 10 ng/ml or greater. For p73 and E-cadherin significant activation was observed at 100 ng/ml of 5AZA. Maximal inhibition of growth, DNA synthesis and colony formation occurred at 100 ng/ml. CONCLUSION: The in vitro antineoplastic and gene re-activation activity of 5AZA is dependent on the concentration of this analog. These data may be helpful in the design of the optimal dose-schedule of 5AZA for the clinical therapy of leukemia.

Antimetabolites, Antineoplastic↗