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Charles L Bennett

Publications and source records attributed to Charles L Bennett.

At least 73 records · Page 4Linked to original sources
PubMed2003

Cost analyses of granulocyte colony stimulating factor: a focus on older patients with cancer.

Granulocyte colony stimulating factor (G-CSF) can reduce the duration of neutropenia following intensive chemotherapy in a variety of settings. The majority of these studies have focused on small cell lung cancer. We review herein published information on costs and cost-effectiveness of G-CSF from clinical studies with patients with small cell lung cancer (SCLC). Medline and Healthstar databases were searched for original research articles that contain cost or cost-effectiveness analyses on the subject. The cost of adjunct treatment with G-CSF was evaluated from four studies of SCLC patients. Benefits included decreased rates of febrile neutropenic events, while cost savings were not identified in three of four studies. These data may be useful to physicians faced with concerns over clinical and economic factors associated with G-CSF use as adjunct therapy for SCLC.

Age Factors↗
PubMed2003

Dissemination of information on potentially fatal adverse drug reactions for cancer drugs from 2000 to 2002: first results from the research on adverse drug events and reports project.

PURPOSE: To describe the clinical findings, occurrence rates, causality evidence, and dissemination media for serious cancer drug-associated adverse drug reactions (ADRs) reported in the postmarketing setting. METHODS: ADRs were termed serious if they resulted in death or severe organ failure. ADR information for oncology drugs from package insert (PI) revisions, so-called Dear Doctor letters, and journal articles was evaluated to identify serious ADRs reported from 2000 to 2002. Timing and content of information disseminated was assessed. RESULTS: Twenty-five serious ADRs associated with 22 oncology drugs were identified after approval. Approximately half of these serious ADRs are associated with drugs approved before 1995. ADRs were described in articles in medical journals (17 ADRs), PI revisions (18 ADRs), and Dear Doctor letters (12 ADRs). PI revisions occurred less than 1 year after peer-reviewed publication for four ADRs. These revisions often differed for similar ADRs that occurred with drugs of the same class. Five of the seven ADRs lacking PI changes occurred with off-label use, for which PI change is not recommended by US Food and Drug Administration (FDA) policy. No cancer drug was withdrawn from the market during the observation period. CONCLUSION: Our findings demonstrate that serious ADRs may be discovered as long as 36 years after a drug receives FDA approval. This suggests a need for continued vigilance and efficient strategies for dissemination of information about ADRs associated with cancer drugs.

Adverse Drug Reaction Reporting Systems↗
PubMed2003

Perspectives on the value of American Society of Clinical Oncology clinical guidelines as reported by oncologists and health maintenance organizations.

PURPOSE: Although the American Society of Clinical Onoclogy's (ASCO) Health Services Research (HSR) committee activities have primarily focused on clinical guideline development, little is known about the value placed on these guidelines by the desired end users. ASCO members and Health Maintenance Organizations (HMOs) were surveyed on the value and implementation of ASCO guidelines. In this article, we summarize our findings. METHODS: ASCO members (n = 1500) were queried about whether they had read ASCO's first four clinical guidelines and technology assessment; whether they agreed with the recommendations; whether they used guidelines in clinical practice; and how guidelines had affected reimbursement. HMOs (n = 131) were queried on how they identify, implement, and value the first four ASCO clinical guidelines. RESULTS: The membership survey indicated that ASCO guidelines were read more often by physicians in private healthcare settings compared with physicians in academic practices (P <.02). Disagreement rates were low for all guidelines (range, 1% to 7%). One quarter of respondents reported that the guidelines were difficult to find and difficult to apply to the practice setting, and approximately one tenth of respondents indicated that the guidelines were difficult to evaluate, interpret, or read. The HMO survey indicated that one third of HMOs reported use of ASCO guidelines, with higher rates of usage by larger HMOs and by those with higher National Committee on Quality Assurance (NCQA) ratings. Respondent HMOs valued guidelines for various purposes and used multiple methods of guideline identification and implementation. CONCLUSION: ASCO guidelines are generally highly supported by physicians and HMOs. Additional studies are needed to identify implementation barriers and to see whether guidelines have resulted in improvements in healthcare.

Attitude of Health Personnel↗
PubMed2003

Surgical outcomes of patients with gastric carcinoma: the importance of primary tumor location and microvessel invasion.

BACKGROUND: This study was done to identify clinicopathologic predictors of disease-free survival (DFS) and overall survival (OS) among patients undergoing potentially curative resections for gastric carcinoma. METHODS: We reviewed 110 patients surgically treated between 1987 and 2001. There were 74 men and 36 women with a mean age of 65.2 years (range 27 to 87 years). Log-rank tests and Kaplan-Meier survival curves were generated to determine clinicopathologic factors influencing DFS and OS. Significant factors were then determined with Cox multivariate analysis. RESULTS: Median survival for all patients was 38.2 months and the estimated 5-year OS was 42.3%. There were no significant differences in DFS or OS for female sex, black race, or age>65. Symptoms associated with lower DFS were weight loss and palpable abdominal mass (P<.05), although none were predictive for OS. Median survival was markedly worse in patients undergoing esophagogastrectomy versus gastrectomy (26.8 vs 52.3 months; P<.05), although there were no significant differences between patients undergoing total gastrectomy versus subtotal gastrectomy. As expected, OS was inversely proportional to the American Joint Committee on Cancer's tumor stage. When compared with patients with partial-thickness tumors (T(1-2)), full-thickness (T(3-4)) tumors had a decreased median survival (63.8 vs 27.9 months; P<.01). Although N(2) stage was associated with decreased survival (20.6 months), patient outcomes were similar for N(0) and N(1) stages (52.5 and 48.8 months). Lymphatic and capillary invasion (21.4 vs 45.3 months; P<.02) and proximal location of primary tumors (28.5 vs 58.6 months; P<.02) were the only other factors adversely affecting survival. Lauren classification and histologic grade were not significant predictors of patient outcomes. CONCLUSIONS: In addition to the American Joint Committee on Cancer stage, microvessel involvement and tumor location are important predictors of DFS and OS in gastric cancer and should be included in risk stratification and selection criteria for patients entering novel adjuvant or neoadjuvant clinical trials.

Adult↗
PubMed2003

Quality of life after a diagnosis of prostate cancer among men of lower socioeconomic status: results from the Veterans Affairs Cancer of the Prostate Outcomes Study.

OBJECTIVES: To evaluate prospectively the health-related and disease-specific quality of life (QOL) at diagnosis and during the first year thereafter for patients with newly diagnosed prostate cancer who received care at Veterans Affairs Medical Centers. METHODS: Interviewers administered the European Organization for Research and Treatment of Cancer-QOL Questionnaire, a valid and reliable measure of health status, to 140 patients with prostate cancer at baseline (at diagnosis, before the initiation of treatment) and at 3 and 12 months thereafter at five Veterans Affairs Medical Centers. The mean changes from baseline values were analyzed statistically for patients with localized disease stratified by treatment group and separately for patients with metastatic disease. RESULTS: Among the 98 men with localized prostate cancer, significant disease-specific QOL changes noted at 3 and 12 months included worsening of urinary and sexual function among men treated with radical prostatectomy or radiotherapy and worsening of urinary function among those who opted for watchful waiting (each P <0.05). Among the 42 men with metastatic prostate cancer, significant decrements in role and social and sexual function were noted at 3 months, but had resolved on average by 12 months of follow-up. CONCLUSIONS: At 12 months, disease-specific QOL decrements persisted for patients with localized disease, but for patients with metastatic disease, disease-specific QOL appeared to return to near baseline (at diagnosis, before treatment initiation) function. Our study, among the first to assess the QOL at baseline before treatment, provides meaningful information on general treatment effects, which are directly relevant to clinicians when discussing treatment options with patients.

Aged↗
PubMed2003

A rapid staging system for predicting mortality from HIV-associated community-acquired pneumonia.

STUDY OBJECTIVE: Community-acquired pneumonia (CAP) accounts for an increasing proportion of the pulmonary infections in individuals with HIV infection. During the mid-1990s, hospital mortality rates for HIV-associated CAP ranged from 0 to 28%. While hospital differences in case mix may account for mortality rate variation, few methods to evaluate illness severity for HIV-associated CAP have been reported previously. The study objective was to develop a staging system for categorizing mortality risk of patients with HIV-associated CAP using information available prior to hospital admission. DESIGN/SETTING/PATIENTS: Retrospective medical records review of 1,415 patients hospitalized with HIV-associated CAP from 1995 to 1997 at 86 hospitals in seven metropolitan areas. MEASUREMENTS: In-patient mortality rate. RESULTS: Hierarchically optimal classification tree analysis was used to develop a preadmission staging system for predicting inpatient mortality. The overall inpatient mortality rate was 9.1%. The significant predictors of mortality included the presence of neurologic symptoms, respiratory rate > or = 25 breaths/min, and creatinine > 1.2 mg/dL. The model identified a five-category staging system, with the mortality rate increasing by stage: 2.3% for stage 1, 5.8% for stage 2, 12.9% for stage 3, 22.0% for stage 4, and 40.5% for stage 5. The classification accuracy of the model was 85.2%. CONCLUSIONS: Our staging system categorizes inpatient mortality risk for patients with HIV-associated CAP using three routinely available variables. The staging system may be useful for guiding clinical decisions about the intensity of patient care and for case-mix adjustment in future studies addressing variation in hospital mortality rates.

AIDS-Related Opportunistic Infections↗
PubMed2003

Cost analyses of adjunct colony stimulating factors for older patients with acute myeloid leukaemia : can they improve clinical decision making?

Colony stimulating factors (CSF) have been shown to reduce the duration of neutropenia following intensive chemotherapy in a variety of settings, with many of these studies targeting older patients with leukaemia. We review the clinical and economic findings for use of growth factors for older adults with acute myelogenous leukaemia (AML). The cost analyses were based on the perspective of the third party payer. One study, conducted by the Southwest Oncology Group (SWOG) randomised 207 AML patients to receive granulocyte colony-stimulating factor (G-CSF) or placebo and found no significant difference in number of infections and in days of hospitalisation, 3 fewer days with an absolute neutrophil count <500 cells/microL with G-CSF, and an estimated incremental cost of only US 120 dollars with G-CSF over placebo (1997 costs). A second study, conducted by the Eastern Cooperative Oncology Group (ECOG), randomised 119 AML patients to receive granulocyte-macrophage colony-stimulating factor (GM-CSF) or placebo and found a reduction in severe infections, 4 fewer days with an absolute neutrophil count <500 cells/microL, no significant difference in the duration of hospitalisation, and estimated cost savings of US 2310 dollars with GM-CSF (1997 costs). These data may be useful to physicians faced with concerns over clinical and economic factors associated with CSF use as adjunct therapy for older persons with AML.

Aged↗
PubMed2003

Post-cardiac catheterization access site complications and low-molecular -weight heparin following cardiac catheterization.

The low molecular weight heparin enoxaparin is often administered to patients on long-term anticoagulation regimens who temporarily discontinue warfarin prior to undergoing invasive procedures. The clinical outcome of all enoxaparin-treated patients who underwent cardiac catheterization or coronary artery interventional procedures (n = 119) was evaluated. A total of 5 patients (4.2%) requiring anticoagulation (3 with chronic atrial fibrillation and 2 with ventricular thrombi) developed severe late enoxaparin-associated hemorrhagic or vascular complications at the femoral arterial puncture site between 3 and 11 days post-procedure. Complications included development of femoral arterial pseudoaneurysm (n = 3), hypotension (systolic blood pressure < 90 mmHg) (n = 2), acute decrease in hemoglobin levels to < 8.5 mg/dl (n = 4) and cardiac arrest (n = 1). In patients receiving standard dose enoxaparin after percutaneous invasive cardiac procedures, there is the potential for delayed and severe access site hemorrhagic and vascular complications.

Aged↗
PubMed2003

Evaluating the total costs of cancer. The Northwestern University Costs of Cancer Program.

The Northwestern University Costs of Cancer Program consists of a series of pilot studies that address the costs of cancer care. The program is designed to serve as a template in preparation for undertaking a large-scale study of a nationally representative sample of cancer patients--i.e., in preparation for a cancer costs and services utilization study in the future. In this article, we outline the theoretical framework associated with a study of cancer costs and summarize findings from our ongoing pilot studies in this area.

Cost of Illness↗
PubMed2002

Use of epoetin in patients with cancer: evidence-based clinical practice guidelines of the American Society of Clinical Oncology and the American Society of Hematology.

Anemia resulting from cancer or its treatment is an important clinical problem increasingly treated with the recombinant hematopoietic growth factor erythropoietin. To address uncertainties regarding indications and efficacy, the American Society of Clinical Oncology and the American Society of Hematology developed an evidence-based clinical practice guideline for the use of epoetin in patients with cancer. The guideline panel found good evidence to recommend use of epoetin as a treatment option for patients with chemotherapy-associated anemia with a hemoglobin (Hgb) concentration below 10 g/dL. Use of epoetin for patients with less severe anemia (Hgb level below 12 g/dL but never below 10 g/dL) should be determined by clinical circumstances. Good evidence from clinical trials supports the use of subcutaneous epoetin thrice weekly (150 U/kg) for a minimum of 4 weeks. Less strong evidence supports an alternative weekly (40 000 U/wk) dosing regimen, based on common clinical practice. With either administration schedule, dose escalation should be considered for those not responding to the initial dose. In the absence of response, continuing epoetin beyond 6-8 weeks does not appear to be beneficial. Epoetin should be titrated once the hemoglobin concentration reaches 12 g/dL. Evidence from one randomized controlled trial supports use of epoetin for patients with anemia associated with low-risk myelodysplasia not receiving chemotherapy; however, there are no published high-quality studies to support its use for anemia in other hematologic malignancies in the absence of chemotherapy. Therefore, for anemic patients with hematologic malignancies it is recommended that physicians initiate conventional therapy and observe hematologic response before considering use of epoetin.

Anemia↗
PubMed2002

Use of epoetin in patients with cancer: evidence-based clinical practice guidelines of the American Society of Clinical Oncology and the American Society of Hematology.

Anemia resulting from cancer, or its treatment, is an important clinical problem increasingly treated with the recombinant hematopoietic growth factor erythropoietin. To address uncertainties regarding indications and efficacy, the American Society of Clinical Oncology and the American Society of Hematology developed an evidence-based clinical practice guideline for the use of epoetin in patients with cancer. The guideline panel found good evidence to recommend use of epoetin as a treatment option for patients with chemotherapy-associated anemia with a hemoglobin level less than 10 g/dL. Use of epoetin for patients with less severe anemia (hemoglobin < 12 g/dL but never below 10 g/dL) should be determined by clinical circumstances. Good evidence from clinical trials supports the use of subcutaneous epoetin thrice weekly (150 U/kg tiw) for a minimum of 4 weeks. Less strong evidence supports an alternative weekly (40,000 U/wk) dosing regimen, based on common clinical practice. With either administration schedule, dose escalation should be considered for those not responding to the initial dose. In the absence of response, continuing epoetin beyond 6 to 8 weeks does not appear to be beneficial. Epoetin should be titrated once the hemoglobin concentration reaches 12 g/dL. Evidence from one randomized controlled trial supports use of epoetin for patients with anemia associated with low-risk myelodysplasia not receiving chemotherapy; however, there are no published high-quality studies to support its use for anemia in other hematologic malignancies in the absence of chemotherapy. Therefore, for anemic patients with hematologic malignancies, it is recommended that physicians initiate conventional therapy and observe hematologic response before considering use of epoetin.

Anemia↗
PubMed2002

TTP/HUS occurring in a simultaneous pancreas/kidney transplant recipient after clopidogrel treatment: evidence of a nonimmunological etiology.

BACKGROUND: One recently reported thrombotic thrombocytopenia purpura/hemolytic uremic syndrome (TTP/HUS) case involved a patient who underwent simultaneous pancreas/kidney (SPK) transplant followed by pancreas rejection and clopidogrel treatment, an antiplatelet agent that has been associated with immunologically mediated TTP/HUS. We present a second case of TTP/HUS developing in an SPK recipient who was also receiving clopidogrel. METHODS: After a stroke, a 48-year-old male SPK transplant recipient received clopidogrel. Four months later, thrombosis and rejection of the transplanted pancreas occurred. One week after a pancreatectomy, TTP/HUS developed that resolved with clopidogrel and sirolimus discontinuation and lowering of the tacrolimus dose. RESULTS: A plasma sample revealed von Willebrand factor cleaving metalloproteinase activity, although no immunoglobulins to the protease were identified. The patient continues taking tacrolimus with normal renal function 1 year after the incident. DISCUSSION: Our findings suggest a nonimmunological etiology for TTP/HUS in clopidogrel-treated transplant recipients. Furthermore, mechanistic focused laboratory studies can facilitate interpretation of case report findings.

Calcineurin↗
PubMed2002

Erythropoietin, uncertainty principle and cancer related anaemia.

BACKGROUND: This study was designed to evaluate if erythropoietin (EPO) is effective in the treatment of cancer related anemia, and if its effect remains unchanged when data are analyzed according to various clinical and methodological characteristics of the studies. We also wanted to demonstrate that cumulative meta-analysis (CMA) can be used to resolve uncertainty regarding clinical questions. METHODS: Systematic Review (SR) of the published literature on the role of EPO in cancer-related anemia. A cumulative meta-analysis (CMA) using a conservative approach was performed to determine the point in time when uncertainty about the effect of EPO on transfusion-related outcomes could be considered resolved. PARTICIPANTS: Patients included in randomized studies that compared EPO versus no therapy or placebo. MAIN OUTCOME MEASURES: Number of patients requiring transfusions. RESULTS: Nineteen trials were included. The pooled results indicated a significant effect of EPO in reducing the number of patients requiring transfusions [odds ratio (OR) = 0.41; 95%CI: 0.33 to 0.5; p < 0.00001;relative risk (RR) = 0.61; 95% CI: 0.54 to 0.68]. The results remain unchanged after the sensitivity analyses were performed according to the various clinical and methodological characteristics of the studies. The heterogeneity was less pronounced when OR was used instead of RR as the measure of the summary point estimate. Analysis according to OR was not heterogeneous, but the pooled RR was highly heterogeneous. A stepwise metaregression analysis did point to the possibility that treatment effect could have been exaggerated by inadequacy in allocation concealment and that larger treatment effects are seen at hb level > 11.5 g/dl. We identified 1995 as the point in time when a statistically significant effect of EPO was demonstrated and after which we considered that uncertainty about EPO efficacy was resolved. CONCLUSION: EPO is effective in the treatment of anemia in cancer patients. This could have already been known in 1995 if a CMA had been performed at that time.

Anemia↗
PubMed2002

Racial variation in CAG repeat lengths within the androgen receptor gene among prostate cancer patients of lower socioeconomic status.

PURPOSE: To evaluate (1) whether there were racial differences in the androgen receptor gene CAG repeat length and in clinical or laboratory attributes of prostate cancer at the time of diagnosis; (2) whether there were differences in race, Gleason score, prostate-specific antigen (PSA) level, and stage at diagnosis by androgen receptor gene CAG repeat length; and (3) whether sociodemographic, clinical, and laboratory based factors might be associated with advanced-stage prostate cancer. To our knowledge, our study is the first to report on CAG repeat lengths in a cohort of prostate cancer patients, which includes large numbers of African-American men. METHODS: CAG repeat lengths on the androgen receptor gene were evaluated for 151 African-American and 168 white veterans with prostate cancer. The chi(2) test, t test, and logistic regression analyses were used to evaluate the associations between CAG repeat lengths and race, stage, histologic grade, and PSA levels at diagnosis. RESULTS: The mean age of the cohort at the time of diagnosis was 68.7 years. At presentation, 42.0% had stage D prostate cancer, 26.5% had Gleason scores of 8 to 10, and 53.0% had PSA levels >/= 10 ng/dL. Mean androgen receptor gene CAG repeat length for white veterans was 21.9 (SD, 3.5) versus 19.8 (SD, 3.2) for African-American veterans (P =.001). Men with shorter CAG repeats were more likely to have stage D prostate cancer (P =.09) but were not more likely to have a higher PSA concentration or Gleason score. CONCLUSION: In this cohort of men with prostate cancer, short CAG repeat length on the androgen receptor gene was associated with African-American race and possibly with higher stage but not with other clinical or pathologic findings.

Aged↗
PubMed2002

Systematic review and meta-analysis of monotherapy compared with combined androgen blockade for patients with advanced prostate carcinoma.

BACKGROUND: The current systematic review and meta-analysis compared monotherapy and combined androgen blockade in the treatment of men with advanced prostate carcinoma. Outcomes of interest included overall, cancer specific, and progression-free survival; time to treatment failure; adverse events; and quality of life. METHODS: The literature search identified randomized trials comparing monotherapy (orchiectomy and luteinizing hormone-releasing hormone [LHRH] agonists) with combination therapy using orchiectomy or a LHRH agonist plus a nonsteroidal or steroidal antiandrogen. Dual independent review occurred. The meta-analysis used a random effects model. RESULTS: Twenty-one trials compared survival after monotherapy with survival after combined androgen blockade (n = 6871 patients). The meta-analysis found no statistically significant difference in survival at 2 years between patients treated with combined androgen blockade and those treated with monotherapy (20 trials; hazard ratio [HR] = 0.970; 95% confidence interval [95% CI], 0.866-1.087). The authors determined a statistically significant difference in survival at 5 years that favored combined androgen blockade (10 trials; HR = 0.871; 95% CI, 0.805-0.942). For the subgroup of patients with a good prognosis, there was no statistically significant difference in survival. Adverse effects leading to withdrawal from therapy occurred more often with combined androgen blockade. To the authors' knowledge there is little evidence published to date comparing the effects of combined androgen blockade and monotherapy on quality of life, but the single randomized trial that adequately addressed this outcome reported an advantage for monotherapy over combined androgen blockade. CONCLUSIONS: A thorough examination of the usefulness of combined androgen blockade must balance the modest increase in expected survival observed at 5 years against the increased risk of adverse effects and the potential for adversely affecting the patient's overall quality of life.

Androgen Antagonists↗
PubMed2002

Legal, financial, and public health consequences of HIV contamination of blood and blood products in the 1980s and 1990s.

Ensuring the safety of the blood supply connects politics and science. The business and service sectors share responsibility for the collection and processing of blood donations, and government agencies perform regulatory and surveillance roles. The onset of the AIDS epidemic has challenged the interface among these systems, leading to widespread fears about compromised safety of the blood supply. Because of public concern about blood-supply decisions made in the 1980s, developed countries in the 1990s established reimbursement programs for persons with transfusion-acquired viral infections from blood or blood products, adopted diagnostic tests and procedures that improved the safety of the blood supply, and held criminal judicial investigations of government officials and industry leaders accused of delaying implementation of potential blood-safety measures. In contrast, developing countries continue to struggle with blood-supply safety issues. This paper summarizes the current status of these safety concerns in developed countries, where viral transmission from contaminated blood or blood products is extremely rare, and in developing countries, where up to 10% of HIV infections result from transfusion of blood or blood products.

Blood Donors↗