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1.
Contemp Clin Trials Commun ; 38: 101281, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38419809

RESUMO

Introduction: Slow patient accrual in cancer clinical trials is always a concern. In 2021, the University of Kansas Comprehensive Cancer Center (KUCC), an NCI-designated comprehensive cancer center, implemented the Curated Cancer Clinical Outcomes Database (C3OD) to perform trial feasibility analyses using real-time electronic medical record data. In this study, we proposed a Bayesian hierarchical model to evaluate annual cancer clinical trial accrual performance. Methods: The Bayesian hierarchical model uses Poisson models to describe the accrual performance of individual cancer clinical trials and a hierarchical component to describe the variation in performance across studies. Additionally, this model evaluates the impacts of the C3OD and the COVID-19 pandemic using posterior probabilities across evaluation years. The performance metric is the ratio of the observed accrual rate to the target accrual rate. Results: Posterior medians of the annual accrual performance at the KUCC from 2018 to 2023 are 0.233, 0.246, 0.197, 0.150, 0.254, and 0.340. The COVID-19 pandemic partly explains the drop in performance in 2020 and 2021. The posterior probability that annual accrual performance is better with C3OD in 2023 than pre-pandemic (2019) is 0.935. Conclusions: This study comprehensively evaluates the annual performance of clinical trial accrual at the KUCC, revealing a negative impact of COVID-19 and an ongoing positive impact of C3OD implementation. Two sensitivity analyses further validate the robustness of our model. Evaluating annual accrual performance across clinical trials is essential for a cancer center. The performance evaluation tools described in this paper are highly recommended for monitoring clinical trial accrual.

3.
Cancer ; 129(23): 3783-3789, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37698493

RESUMO

BACKGROUND: This study aimed to understand the differential levels of inflammatory chemokines in association with higher prostate cancer incidence and mortality in African American (AA) men than in Caucasians (CA). METHODS: The authors used a chemokine assay to simultaneously measure 40 chemokines and cytokines levels in the serum of preoperative prostate cancer patients and healthy controls of AA and CA races. Selected chemokines (CXCL2, CXCL5, and CCL23) serum level was validated in 211 serum samples from prostate cancer patients and healthy controls. Differential expression of CXCL5 and CCL23 was analyzed using immunohistochemistry in a representative cohort of prostate tumor tissues of AA and CA races. RESULTS: Race-specific comparisons from 211 serum samples showed significantly higher levels of CXCL2 (control: 3104.0 pg/mL vs. cancer: 2451.0 pg/mL) and CXCL5 (control: 5189.0 pg/mL vs. cancer: 5459.0 pg/mL) in AA men than in CAs (CXCL2; control: 1155.0 pg/mL vs. cancer: 889.3 pg/mL, and CXCL5; control: 1183.0 pg/mL vs. cancer: 977.5 pg/mL). CCL23 differed significantly within and between the races with a lower level in AA cancer cases (454.5 vs. 966.6 pg/mL) than healthy controls (740.5 vs. 1263.0 pg/mL). Patient age, prostate-specific antigen, or Gleason scores were not significantly associated with these chemokines. Immunostaining for CXCL5 and CCL23 in a representative cohort of archival prostate tissues displayed significantly higher CXCL5 in prostate tumors than in adjacent benign tissues, whereas CCL23 was nondetectable in most of the analyzed tumor tissues. CONCLUSION: Lower levels of CCL23 in AA prostate cancer patient sera and tumor tissues and high CXCL2 and CXCL5 may contribute to aggressive prostate cancer, as often seen in AA men. The disproportionate levels of serum chemokines associated with race warrant further exploration to improve equitability in precision oncology to benefit prostate cancer patients.


Assuntos
Medicina de Precisão , Neoplasias da Próstata , Masculino , Humanos , Fatores Raciais , Neoplasias da Próstata/patologia , Quimiocinas , Antígeno Prostático Específico
4.
Cancer Res Commun ; 3(7): 1166-1172, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37415746

RESUMO

How the socioeconomic factors intersect for a particular patient can determine their susceptibility to financial toxicity, what costs they will encounter during treatment, the type and quality of their care, and the potential work impairments they face. The primary goal of this study was to evaluate financial factors leading to worsening health outcomes by the cancer subtype. A logistic model predicting worsening health outcomes while assessing the most influential economic factors was constructed by the University of Michigan Health and Retirement Study. A forward stepwise regression procedure was implemented to identify the social risk factors that impact health status. Stepwise regression was done on data subsets based on the cancer types of lung, breast, prostate, and colon cancer to determine whether significant predictors of worsening health status were different or the same across cancer types. Independent covariate analysis was also conducted to cross-validate our model. On the basis of the model fit statistics, the two-factor model has the best fit, that is, the lowest AIC among potential models of 3270.56, percent concordance of 64.7, and a C-statistics of 0.65. The two-factor model used work impairment and out-of-pocket costs, significantly contributing to worsening health outcomes. Covariate analysis demonstrated that younger patients with cancer experienced more financial burdens leading to worsening health outcomes than elderly patients aged 65 years and above. Work impairment and high out-of-pocket costs were significantly associated with worsening health outcomes among cancer patients. Matching the participants who need the most financial help with appropriate resources is essential to mitigate the financial burden. Significance: Among patients with cancer, work impairment and out-of-pocket are the two primary factors contributing to adverse health outcomes. Women, African American or other races, the Hispanic population, and younger individuals have encountered higher work impairment and out-of-pocket costs due to cancer than their counterparts.


Assuntos
Neoplasias do Colo , Estresse Financeiro , Masculino , Idoso , Humanos , Feminino , Efeitos Psicossociais da Doença , Atenção à Saúde , Nível de Saúde
5.
JNCI Cancer Spectr ; 7(4)2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37326961

RESUMO

PURPOSE: This study investigated how cancer diagnosis and treatment lead to career disruption and, consequently, loss of income and depletion of savings. DESIGN: This study followed a qualitative descriptive design that allowed us to understand the characteristics and trends of the participants. METHOD: Patients recruited (n = 20) for this study were part of the University of Kansas Cancer Center patient advocacy research group (Patient and Investigator Voices Organizing Together). The inclusion criteria were that participants must be cancer survivors or co-survivors, be aged 18 years or older, be either employed or a student at the time of cancer diagnosis, have completed their cancer treatment, and be in remission. The responses were transcribed and coded inductively to identify themes. A thematic network was constructed based on those themes, allowing us to explore and describe the intricacies of the various themes and their impacts. RESULTS: Most patients had to quit their jobs or take extended absences from work to handle treatment challenges. Patients employed by the same employer for longer durations had the most flexibility to balance their time between cancer treatment and work. Essential, actionable items suggested by the cancer survivors included disseminating information about coping with financial burdens and ensuring that a nurse and financial navigator were assigned to every cancer patient. CONCLUSIONS: Career disruption is common among cancer patients, and the financial burden due to their career trajectory is irreparable. The financial burden is more prominent in younger cancer patients and creates a cascading effect that financially affects close family members.


Assuntos
Sobreviventes de Câncer , Neoplasias , Humanos , Renda , Sobreviventes , Adaptação Psicológica
6.
Cancer Med ; 12(4): 4638-4646, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35852258

RESUMO

BACKGROUND: This research study aimed to evaluate the financial burden among older cancer patients and its corresponding risk factors. Factors such as increasing treatment costs and work limitations often lead cancer patients to bankruptcy and poor quality of life. These consequences, in turn, can cause higher mortality rates among these patients. METHODS: This retrospective cohort study utilized data from the Health Retirement Study (HRS), conducted by the University of Michigan (N = 18,109). Eligible participants had responses captured from years 2002 to 2016. Participants were classified according to any self-reported cancer diagnosis (yes or no) and were compared on the basis of financial, work, and health-related outcomes. Propensity score (PS) matching was applied to reduce the effects of potential confounding factors. Also only, individuals with an age ≥50 and ≤85 during Wave 6 were retained. RESULTS: Multivariate analysis with random effects revealed several indicators of financial burden when comparing participants with a cancer diagnosis to those with no history of cancer. Mean out-of-pocket costs associated with a cancer diagnosis were $1058 higher when compared to participants with no history of cancer, suggesting that even cancer patients with insurance coverage faced out-of-pocket costs. Respondents with cancer patients had higher odds of encountering financial hardship if they are facing Work Limitations (OR = 2.714), Regular use of Medications (OR = 2.518), Hospital Stays (OR = 2.858), Declining Health (OR = 2.349), or were being covered under government health insurance (OR = 5.803) than respondents who did not have cancer, or suffered from mental health issues such as Depression (OR = 0.901). CONCLUSION: Cancer patients contend with increasing financial costs during their treatment. However, most newly diagnosed patients are not aware of these costs and are given few resources to handle them.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Estresse Financeiro , Estudos Retrospectivos , Efeitos Psicossociais da Doença , Seguro Saúde , Gastos em Saúde
7.
Prev Med Rep ; 23: 101446, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34168953

RESUMO

Breast cancer screening guidelines serve as crucial evidence-based recommendations in deciding when to begin regular screenings. However, due to developments in breast cancer research and differences in research interpretation, screening guidelines can vary between organizations and within organizations over time. This leads to significant lapses in adopting updated guidelines, variable decision making between physicians, and unnecessary screening for low to moderate risk patients (Jacobson and Kadiyala, 2017; Corbelli et al., 2014). For analysis, risk factors were assessed for patient screening behaviors and results. The outcome variable for the first analysis was whether the patient had undergone screening. The risk factors considered were age, marital status, education level, rural versus urban residence, and family history of breast cancer. The outcome variable for the second analysis was whether patients who had undergone breast cancer screening presented abnormal results. The risk factors considered were age, Body Mass Index, family history, smoking and alcohol status, hormonal contraceptive use, Hormone Replacement Therapy use, age of first pregnancy, number of pregnancies (parity), age of first menses, rural versus urban residence, and whether or not patients had at least one child. Logistic regression analysis displayed strong associations for both outcome variables. Risk of screening nonattendance was negatively associated with age as a continuous variable, age as a dichotomous variable, being married, any college education, and family history. Risk of one or more abnormal mammogram findings was positively associated with family history, and hormonal contraceptive use. This procedure will be further developed to incorporate additional risk factors and refine the analysis of currently implemented risk factors.

8.
Contemp Clin Trials Commun ; 22: 100774, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34027224

RESUMO

The primary goal for any clinical trial after it receives a funding notification is to receive regulatory approval and initiate the trial for recruitment. Every trial must go through documentation and regulatory process before it can start recruiting participants and collecting data; this initial process of review and approval is known as the study start-up process (SSU). We evaluated the average time taken for studies to receive approvals. Using data from clinical trials conducted at the University of Kansas Medical Center, various times to reach the start of the study were calculated based on the dates of individual study. The results of this analysis showed that chart review studies and investigator-initiated trials had a shorter time to activation than other types of studies. Additionally, single-center studies had a shorter activation time than multi-center studies. The analysis also demonstrated that the overall processing time consistently had been reduced over time.

9.
Trauma Surg Acute Care Open ; 5(1): e000605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33313417

RESUMO

Anticoagulant-associated traumatic intracranial hemorrhage (tICrH) is a devastating injury with high morbidity and mortality. For survivors, treating clinicians face the dilemma of restarting oral anticoagulation with scarce evidence to guide them. Thromboembolic risk is high from the bleeding event, patients' high baseline risks, that is, the pre-existing indication for anticoagulation, and the risk of immobility after the bleeding episode. This must be balanced with potentially devastating hematoma expansion or new hemorrhagic lesions. Retrospective evidence and expert opinion support restarting oral anticoagulants in most patients with tICrH, but timing is uncertain. Researchers have failed to make clear distinctions between tICrH and spontaneous intracranial hemorrhage (sICrH), which have differing natural histories. While both appear to benefit from restarting, sICrH has a higher rebleeding risk and similar or lower thrombotic risk. Clinical equipoise on restarting is also divergent. In sICrH, equipoise is centered on whether to restart. In tICrH, it is centered on when. Several prospective randomized clinical trials are ongoing or about to start to examine the risk-benefit of restarting. Most of them are restricted to patients with sICrH, with antiplatelet control groups. Most are also restricted to direct oral anticoagulants (DOACs), as they are associated with a lower overall risk of ICrH. There is some overlap with tICrH via subdural hematoma, and one trial is specific to restart timing with DOACs in only traumatic cases. This is a narrative review of the current evidence for restarting anticoagulation and restart timing after tICrH along with a summary of the ongoing and planned clinical trials.

10.
Cancers (Basel) ; 12(10)2020 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-33081054

RESUMO

In this study, we investigated the potential of MIC-1 (macrophage inhibitory cytokine-1) on the severity of prostate cancer between African American men and Caucasians. Differences between the races were examined using Mann-Whitney tests for continuous variables and Fisher's exact tests for categorical variables. Pearson's correlation coefficient was used to identify associations between continuous measures across all samples and within each race. Analysis of variance, including clinical parameters, was used to identify differences in serum and urine MIC-1 levels between races. We found significant differences between the two races for age (p = 0.01), Gleason scores (p = 0.01), and stage of disease (p = 0.03). African American men in the study had higher Gleason scores (mean = 6.9) than Caucasians (mean = 6.5), during earlier stages of the disease. In Caucasian men with prostate cancer, serum MIC-1 expression was positively associated with age (r = 0.7, p < 0.01). However, African American men had highly expressed MIC-1 and high Gleason scores (r = 0.16, p = 0.3). Interestingly, the urine MIC-1 level was significantly higher in African American men with prostate cancer than in Caucasian patients. It appeared to be more sensitive and specific for African Americans (AUC = 0.85 vs. 0.56). Thus, high circulatory MIC-1 in prostate cancer patients may indicate MIC-1 as a potential biomarker to improve the diagnostic ability of an aggressive stage of prostate cancer in African American men. However, a larger cohort of sample analysis is required to validate these observations.

11.
Contemp Clin Trials Commun ; 18: 100579, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32510004

RESUMO

Early phase clinical trials are the first step in testing new medications and therapeutics developed by clinical and biomedical investigators. These trials aim to find a safe dose of a newly targeted drug (phase I) or find out more about the side effects and early signals of treatment efficacy (phase II). In a research institute, many biomedical investigators in oncology are encouraged to initiate such trials early in their careers as part of developing their research portfolio. These investigator-initiated trials (IITs) are funded internally by the University of Kansas Cancer Center or partially funded by pharmaceutical companies. As financial, administrative, and practical considerations play an essential role in the successful completion of IITs, it is imperative to efficiently allocate resources to plan, design, and execute these studies within the allotted time. This manuscript describes monitoring tools and processes to improve the efficiency, cost-effectivness, and reliability of IITs. The contributions of this team to processes such as: participant recruitment, feasibility analysis, clinical trial design, accrual monitoring, data management, interim analysis support, and final analysis and reporting are described in detail. This manuscript elucidates how, through the aid of technology and dedicated personnel support, the efficiency of IIT-related processes can be improved. Early results of these initiatives look promising, and the Biostatistics and Informatics team intends to continue fostering innovative methodologies to enhance cancer research by improving the efficiency of IITs.

12.
Cancer Inform ; 18: 1176935119886831, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798300

RESUMO

To fully support their role in translational and personalized medicine, biorepositories and biobanks must continue to advance the annotation of their biospecimens with robust clinical and laboratory data. Translational research and personalized medicine require well-documented and up-to-date information, but the infrastructure used to support biorepositories and biobanks can easily be out of sync with the host institution. To assist researchers and provide them with accurate pathological, epidemiological, and bio-molecular data, the Biospecimen Repository Core Facility (BRCF) at the University of Kansas Medical Center (KUMC) merges data from medical records, the tumor registry, and pathology reports using the Curated Cancer Clinical Outcomes Database (C3OD). In this report, we describe the utilization of C3OD to optimally retrieve and dispense biospecimen samples using these 3 data sources and demonstrate how C3OD greatly increases the efficiency of obtaining biospecimen samples for the researchers.

13.
Clin Trials ; 16(6): 657-664, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31451012

RESUMO

BACKGROUND: Monitoring subject recruitment is key to the success of a clinical trial. Accordingly, researchers have developed accrual-monitoring tools to support the design and conduct of trials. At an institutional level, delays in identifying studies with high risk of accrual failure can lead to inefficient and costly trials with little chances of meeting study objectives. Comprehensive accrual monitoring is necessary to the success of the research enterprise. METHODS: This article describes the design and implementation of the University of Kansas Cancer Center Accrual Prediction Program, a web-based platform was developed to support comprehensive accrual monitoring and prediction for all active clinical trials. The Accrual Prediction Program provides information on accrual, including the predicted completion date, predicted number of accrued subjects during the pre-specified accrual period, and the probability of achieving accrual targets. It relies on a Bayesian accrual prediction model to combine protocol information with real-time trial enrollment data and disseminates results via web application. RESULTS: First released in 2016, the Accrual Prediction Program summarizes enrollment information for active studies categorized by various trial attributes. The web application supports real-time evidence-based decision making for strategic resource allocation and study management of over 120 ongoing clinical trials at the University of Kansas Cancer Center. CONCLUSION: The Accrual Prediction Program makes accessing comprehensive accrual information manageable at an institutional level. Cancer centers or even entire institutions can reproduce the Accrual Prediction Program to achieve real-time comprehensive monitoring and prediction of subject accrual to aid investigators and administrators in the design, conduct, and management of clinical trials.


Assuntos
Ensaios Clínicos como Assunto/métodos , Modelos Estatísticos , Neoplasias/terapia , Seleção de Pacientes , Teorema de Bayes , Institutos de Câncer , Ensaios Clínicos como Assunto/estatística & dados numéricos , Humanos , Internet , Kansas , Projetos de Pesquisa
14.
Lab Invest ; 99(1): 85-92, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30353131

RESUMO

Distinct populations of effector memory T cells use different homing receptors to traffic to the skin and gut. Whether tissue-selective T cells are needed for early rejection of a neoplasm growing in these tissues remains an open question. We chose to study an allogeneic tumor model because growth of such a fully mismatched tumor would signify a profound immune deficit. We implanted allogeneic tumor cells in the skin or gut of mice deficient in either α(1,3) fucosyltransferases IV and VII, enzymes critical for generating E-selectin ligands on skin-homing T cells, or ß7 integrin, a component of the α4ß7 integrin ligand for the mucosal adressin MAdCAM. During the first 9 days after tumor implantation, FucTVII-/- mice showed a profoundly impaired capacity to reject tumors growing in the skin, but readily rejected tumors implanted in the gut. Rejection of tumors in the skin was even more impaired in mice deficient in both FucTIV and FucTVII. This impairment was corrected by infusion of T cells from normal mice. By contrast, ß7 integrin-/- mice showed profoundly impaired rejection of tumors in the gut, but no defect in the skin tumor rejection. These differences were unrelated to antigen recognition or effector function of T cells, since all strains of mice were capable of generating tumor-specific CTLs in vitro against the tumor cell line used in vivo. These results demonstrate that T-cell homing defects in vivo impair immune surveillance of peripheral epithelial tissues in a specific and selective fashion.


Assuntos
Neoplasias/imunologia , Linfócitos T/fisiologia , Aloenxertos , Animais , Linhagem Celular Tumoral , Fucosiltransferases/metabolismo , Cadeias beta de Integrinas/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Knockout , Transplante de Neoplasias
15.
Acad Radiol ; 26(7): 893-899, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30318287

RESUMO

RATIONALE AND OBJECTIVES: To evaluate radiologic and pathologic features associated with upgrade of atypical ductal hyperplasia (ADH) to ductal carcinoma in situ or invasive breast cancer at surgical excision, in order to identify patients who may consider alternatives to excision. MATERIALS AND METHODS: This retrospective analysis examined patients who underwent surgical excision of biopsy-proven ADH at our institution. Imaging and pathology from biopsy were reviewed to determine radiologic (lesion size, radiologic abnormality, biopsy type, needle gauge, number of cores, percent of lesion removed) and pathologic features (histologic calcifications, presence of necrosis, micropapillary features, extent of ADH) associated with ADH upgrade. RESULTS: One hundred twenty four cases of percutaneous biopsy-proven ADH with subsequent excision were included. The overall upgrade rate was 17.7% (n = 22), with 17 cases to ductal carcinoma in situ and five to invasive cancer. Radiologic features associated with a lower upgrade rate were smaller lesion size (p = 0.032) and larger percent of lesion removed at biopsy (p = 0.047). Larger needle gauge at biopsy (p = 0.070), absence of necrosis (p = 0.051) and focal ADH (<3 foci, p = 0.12) were nearly associated with a lower rate of upgrade and were included for the purpose of multi parameter analyses. CONCLUSION: For women with ADH identified on percutaneous biopsy, the risk of upgrade may in part be determined by lesion size, percent of lesion removed at biopsy, presence of necrosis, and extent of ADH. Using a combination of these radiographic and pathologic features to stratify patients with biopsy-proven ADH may help identify women who could be considered for alternative treatment options.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Idoso , Biópsia com Agulha de Grande Calibre/instrumentação , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Necrose/patologia , Agulhas , Gradação de Tumores , Estudos Retrospectivos , Carga Tumoral
17.
AJR Am J Roentgenol ; 210(1): W22-W28, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29045183

RESUMO

OBJECTIVE: Supplemental screening with ultrasound has been shown to detect additional breast malignancies in women with dense breast tissue and normal mammogram findings. The frequency of supplemental screening with automated breast ultrasound and the effect and type of breast tissue density notification on automated screening breast ultrasound utilization rates are unknown. MATERIALS AND METHODS: We examined normal mammogram results letters for patients with heterogeneously or extremely dense breast tissue between July 1, 2013, and June 30, 2014, by type of results letter, notification method, and sociodemographic characteristics. Logistic regression was used to examine the association between type of results letter and subsequent automated screening breast ultrasound. RESULTS: Among 3012 women with dense breast tissue and normal mammogram findings, 15% returned for supplemental automated screening breast ultrasound within 18 months of results letter notification. Compared with a similarly sized control group of women who did not undergo automated ultrasound, a significantly greater proportion of patients (86.9%) returned for breast ultrasound if they received a results letter indicating breast density in combination with a courtesy phone call (p < 0.001). Patients who received results letters with breast density notification including a statement that they may benefit from additional screening with automated breast ultrasound examination were 9.91 times (95% CI, 6.08-16.16) more likely to return for the examination than patients who did not receive breast density notification or mention of supplemental screening. CONCLUSION: Patient breast density notification and radiologists' recommendations for supplemental screening with breast ultrasound increase patient utilization of automated screening breast ultrasound examinations.


Assuntos
Densidade da Mama , Neoplasias da Mama/diagnóstico por imagem , Comunicação , Detecção Precoce de Câncer , Aceitação pelo Paciente de Cuidados de Saúde , Ultrassonografia Mamária , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Preferência do Paciente , Estudos Retrospectivos , Fatores Socioeconômicos
18.
J Biopharm Stat ; 28(5): 824-839, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29172970

RESUMO

Frequentist design for two-arm randomized Phase II clinical trials with outcomes from the exponential dispersion family was proposed previously, where the total sample sizes are minimized under multiple constraints on the standard errors of the estimated group means and their difference. This design was generalized from an approach specific for dichotomous outcomes. The two previous approaches measure the central tendency of each group and treatment effect based on mean and difference in means. Other measures such as median or hazard ratio are more appropriate under certain situations. In addition, the frequentist approaches assume that unknown parameters are fixed values. This does not reflect the reality that uncertainty always exists for unknowns. Compared to the frequentist methods, the Bayesian approach offers a flexible way to measure central tendency and treatment effect, and incorporate uncertainty in parameters of interest into considerations. In this article, we generalize a Bayesian design for Phase II clinical trials with endpoints in the exponential family from the two previously developed frequentist approaches. The proposed design minimizes the total sample sizes under pre-specified constraints on the expected length of posterior credible intervals for measures of treatment effect and central tendency in each group. The design is applicable for trials with fixed or optimal randomization allocation ratio and can be applied under adaptive procedure. Examples of method implementations are provided for different types of endpoints from the exponential family in both fixed and adaptive settings.


Assuntos
Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Determinação de Ponto Final/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Teorema de Bayes , Ensaios Clínicos Fase II como Assunto/métodos , Determinação de Ponto Final/métodos , Humanos , Neoplasias/diagnóstico , Neoplasias/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Taxa de Sobrevida/tendências , Carga Tumoral
19.
J Radiol Prot ; 37(4): N42-N48, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28936988

RESUMO

Our purpose in this study was to compare delivered radiation exposure via computed tomography dose index volume (CTDIvol) and dose length production (DLP) measurements from computed tomography (CT) examinations performed on scanners with and without image-quality enhancing iterative reconstruction (IR) software. A retrospective analysis was conducted on randomly selected chest, abdomen, and/or pelvis CT examinations from three different scanners from 1 January 2013 to 31 December 2013. CTDIvol and DLP measurements were obtained from two CT scanners with and one CT scanner without IR software. To evaluate inter-scanner variability, we compared measurements from the same model CT scanners, one with and one without IR software. To evaluate intra-scanner variability, we compared measurements between two scanners with IR software from different manufacturers. CT scanners with IR software aided in the overall reduction in radiation exposure, measured as CTDIvol by 30% and DLP by 39% when compared to a scanner without IR. There was no significant difference in CTDlvol or DLP measurements across different manufacturers with IR software. As a result, IR software significantly decreased the radiation exposure to patients, but there were no differences in radiation measurements across CT manufacturers with IR software.


Assuntos
Exposição à Radiação/prevenção & controle , Proteção Radiológica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador , Tomógrafos Computadorizados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Software
20.
J Drugs Dermatol ; 15(5): 527-32, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27168261

RESUMO

New melanoma drugs bring enormous benefits but do so at significant costs. Because melanoma grows deeper and deadlier over time, deeper lesions are costlier due to increased sentinel lymph node biopsy, chemotherapy, and disease-associated income loss. Prior studies have justified pigmented lesion biopsies on a "value per life" basis; by contrast we sought to assess how many biopsies are justified per melanoma found on a purely economic basis. We modeled how melanomas in the United States would behave if diagnosis were delayed by 6 months, eg, not biopsied, only observed until the next surveillance visit. Economic loss from delayed biopsy is the obverse of economic benefit of performing biopsy earlier. Growth rates were based on Liu et al. The results of this study can be applied to all patients presenting to dermatologists with pigmented skin lesions suspicious for melanoma. In-situ melanomas were excluded because no studies to date have modeled growth rates analogous to those for invasive melanoma. We assume conservatively that all melanomas not biopsied initially will be biopsied and treated 6 months later. Major modeled costs are (1) increased sentinel lymph node biopsy, (2) increased chemotherapy for metastatic lesions using increased 5-yr death as metastasis marker, and (3) income loss per melanoma death at $413,370 as previously published. Costs avoided by diagnosing melanoma earlier justify 170 biopsies per melanoma found. Efforts to penalize "unnecessary" biopsies may be economically counterproductive.

J Drugs Dermatol. 2016;15(5):527-532.


Assuntos
Análise Custo-Benefício/economia , Detecção Precoce de Câncer/economia , Melanoma/diagnóstico , Melanoma/economia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/economia , Detecção Precoce de Câncer/métodos , Diagnóstico Precoce , Feminino , Humanos , Masculino , Melanoma/epidemiologia , Programa de SEER/economia , Neoplasias Cutâneas/epidemiologia , Estados Unidos/epidemiologia , Melanoma Maligno Cutâneo
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