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Accurate identification of tissue types in surgical margins is essential for ensuring the complete removal of cancerous cells and minimizing the risk of recurrence. The objective of this study was to explore the clinical utility of Raman spectroscopy for the detection of oral squamous cell carcinoma (OSCC) in both tumor and healthy tissues obtained from surgical resection specimens during surgery. This study enrolled a total of 64 patients diagnosed with OSCC. Among the participants, approximately 50% of the cases were classified as the most advanced stage, referred to as T4. Raman experiments were conducted on cryopreserved tissue samples collected from patients diagnosed with OSCC. Prominent spectral regions containing key oral biomarkers were analyzed using the partial least squares-support vector machine (PLS-SVM) method, which is a powerful multivariate analysis technique for discriminant analysis. This approach effectively differentiated OSCC tissue from non-OSCC tissue, achieving a sensitivity of 95.7% and a specificity of 93.3% with 94.7% accuracy. In the current study, Raman analysis of fresh tissue samples showed that OSCC tissues contained significantly higher levels of nucleic acids, proteins, and several amino acids compared to the adjacent healthy tissues. In addition to differentiating between OSCC and non-OSCC tissues, we have also explored the potential of Raman spectroscopy in classifying different stages of OSCC. Specifically, we have investigated the classification of T1, T2, T3, and T4 stages based on their Raman spectra. These findings emphasize the importance of considering both stage and subsite factors in the application of Raman spectroscopy for OSCC analysis. Future work will focus on expanding our tissue sample collection to better comprehend how different subsites influence the Raman spectra of OSCC at various stages, aiming to improve diagnostic accuracy and aid in identifying tumor-free margins during surgical interventions.
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BACKGROUND: There is no agreed upon standard of care for borderline-resectable pancreatic cancer (BRPC) or locally-advanced pancreatic cancer (LAPC) patients regarding the benefit of chemotherapy or radiation alone or in combination. PATIENTS AND METHODS: We completed a retrospective cohort analysis of BRPC and LAPC patients at a cancer center with expertise in multi-disciplinary pancreatic ductal adenocarcinoma (PDAC) treatment over a 5-year period from 03/01/2014 to 03/01/2019 (cut-off date). The total evaluable newly diagnosed, treatment naïve, BRPC, and LAPC patients with adequate organ function and ability to obtain treatment after multidisciplinary review was 52 patients. After analysis, patients were evaluated for rates of resection, extent of resection (R0 or R1), median progression-free survival (mPFS), and median overall survival (mOS). RESULTS: Patients were treated with chemotherapy alone (gemcitabine and nab-paclitaxel = 77% (20/26); FOLFIRINOX = 19% (5/26); single agent gemcitabine 3.8% (1/26)), or chemotherapy followed by chemoradiation (gemcitabine +5 Gy × 5 weeks), or chemoradiation alone prior to re-staging and potential resection. Of the 29% (15/52) of patients who went on to surgical resection, 73% (11/15) achieved R0 resection. An R0 resection was achieved in 35% (9/26) of patients treated with chemotherapy alone, 7.6% (1/13) in a patient treated with chemotherapy followed by radiation, and 7.6% (1/13) with concurrent chemoradiotherapy alone. Chemotherapy alone achieved a mPFS of 16.4 months (p < 0.0025) and mOS of 26.2 months (p < 0.0001), chemotherapy followed by chemoradiation was 13.0 months and 14.9 months respectively, while concurrent chemoradiotherapy was 6.9 months and 7.3 months. CONCLUSIONS AND RELEVANCE: BRPC and LAPC patients capable of surgery after only receiving neoadjuvant treatment with chemotherapy had higher rates of R0 resection with prolonged median PFS and OS compared with any patient needing combination chemotherapy with radiotherapy.
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Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/patologia , Terapia Neoadjuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Retrospectivos , Fluoruracila , Leucovorina , Neoplasias PancreáticasRESUMO
While randomized controlled trials (RCTs) are the gold standard for estimating treatment effects in medical research, there is increasing use of and interest in using real-world data for drug development. One such use case is the construction of external control arms for evaluation of efficacy in single-arm trials, particularly in cases where randomization is either infeasible or unethical. However, it is well known that treated patients in non-randomized studies may not be comparable to control patients-on either measured or unmeasured variables-and that the underlying population differences between the two groups may result in biased treatment effect estimates as well as increased variability in estimation. To address these challenges for analyses of time-to-event outcomes, we developed a meta-analytic framework that uses historical reference studies to adjust a log hazard ratio estimate in a new external control study for its additional bias and variability. The set of historical studies is formed by constructing external control arms for historical RCTs, and a meta-analysis compares the trial controls to the external control arms. Importantly, a prospective external control study can be performed independently of the meta-analysis using standard causal inference techniques for observational data. We illustrate our approach with a simulation study and an empirical example based on reference studies for advanced non-small cell lung cancer. In our empirical analysis, external control patients had lower survival than trial controls (hazard ratio: 0.907), but our methodology is able to correct for this bias. An implementation of our approach is available in the R package ecmeta.
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Pesquisa Biomédica , Humanos , ViésRESUMO
BACKGROUND: Primary small cell carcinoma of the pancreas (SCCP) is a rare malignant neuroendocrine carcinoma (NEC). Typically, it presents with lymphovascular invasion as well as metastasis at the time of diagnosis which portends a dismal prognosis. Treatment is typically based on therapy used for other aggressive NECs such as small cell lung cancer. Although multimodal surgery, radiation and chemotherapy may improve prognosis, the outcome generally remains poor. CASE PRESENTATION: Here we present a primary SCCP managed with neoadjuvant multi-agent chemotherapy combined with radiotherapy and surgery CONCLUSIONS: Multi-disciplinary therapy resulted in an ongoing 28 + month radiographic complete response and overall survival.
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Carcinoma Neuroendócrino , Carcinoma de Células Pequenas , Neoplasias Pulmonares , Neoplasias Pancreáticas , Carcinoma de Pequenas Células do Pulmão , Carcinoma Neuroendócrino/terapia , Carcinoma de Células Pequenas/terapia , Humanos , Recém-Nascido , Neoplasias Pulmonares/terapia , Pâncreas , Neoplasias Pancreáticas/terapia , PrognósticoRESUMO
Lymphoepithelioma-like hepatocellular carcinoma (LEL-HCC) is a very rare neoplasm, with distinct epidemiologic, morphologic and clinical characteristics. Molecular mechanistic insight into the pathogenesis of this carcinoma suggests a pivotal role for the host immune system in the proliferation and progression of this tumor. However, while detailed genomic profiling of these hepatic tumors have revealed an intra-tumoral inflammatory mutational signature that may predispose to immune checkpoint inhibitor efficacy, no published report has described their use in this tumor type. Unfortunately, with near 100 cases of LEL-HCC reported in the literature to date and the majority of cases confined to localized and resectable disease, current evidence-based practices in the unresectable setting are lacking, with unknown benefit of chemotherapy or immunotherapy. We report on the case of a 68 year-old man with unresectable, advanced LEL-HCC who had evidence of disease stability after starting on the immune checkpoint inhibitor nivolumab. His disease response persisted off therapy for over a year and was potentially augmented by radiotherapy at the site of local progression. For this extremely rare tumor subtype, this case highlights the potential efficacy and safety of immune checkpoint blockade in LEL-HCC and reinforces the need for more robust, large-scale analysis of patients with these rare tumors to better evaluate treatment strategies and outcomes.
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PURPOSE: IDO1 induces immune suppression in T cells through l-tryptophan (Trp) depletion and kynurenine (Kyn) accumulation in the local tumor microenvironment, suppressing effector T cells and hyperactivating regulatory T cells (Treg). Navoximod is an investigational small-molecule inhibitor of IDO1. This phase I study evaluated safety, tolerability, pharmacokinetics, and pharmacodynamics of navoximod in combination with atezolizumab, a PD-L1 inhibitor, in patients with advanced cancer. PATIENTS AND METHODS: The study consisted of a 3+3 dose-escalation stage (n = 66) and a tumor-specific expansion stage (n = 92). Navoximod was given orally every 12 hours continuously for 21 consecutive days of each cycle with the exception of cycle 1, where navoximod administration started on day -1 to characterize pharmacokinetics. Atezolizumab was administered by intravenous infusion 1,200 mg every 3 weeks on day 1 of each cycle. RESULTS: Patients (n = 157) received navoximod at 6 dose levels (50-1,000 mg) in combination with atezolizumab. The maximum administered dose was 1,000 mg twice daily; the MTD was not reached. Navoximod demonstrated a linear pharmacokinetic profile, and plasma Kyn generally decreased with increasing doses of navoximod. The most common treatment-related AEs were fatigue (22%), rash (22%), and chromaturia (20%). Activity was observed at all dose levels in various tumor types (melanoma, pancreatic, prostate, ovarian, head and neck squamous cell carcinoma, cervical, neural sheath, non-small cell lung cancer, triple-negative breast cancer, renal cell carcinoma, urothelial bladder cancer): 6 (9%) dose-escalation patients achieved partial response, and 10 (11%) expansion patients achieved partial response or complete response. CONCLUSIONS: The combination of navoximod and atezolizumab demonstrated acceptable safety, tolerability, and pharmacokinetics for patients with advanced cancer. Although activity was observed, there was no clear evidence of benefit from adding navoximod to atezolizumab.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Humanos , Imidazóis/administração & dosagem , Imidazóis/farmacocinética , Indóis/administração & dosagem , Indóis/farmacocinética , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/diagnóstico , Neoplasias/etiologia , Neoplasias/metabolismo , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
BACKGROUND: Indoleamine-2,3-dioxygenase 1 (IDO1) catalyzes the oxidation of tryptophan into kynurenine and is partially responsible for acquired immune tolerance associated with cancer. The IDO1 small molecule inhibitor navoximod (GDC-0919, NLG-919) is active as a combination therapy in multiple tumor models. METHODS: This open-label Phase Ia study assessed safety, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary anti-tumor activity of navoximod in patients with recurrent/advanced solid tumors, administered as 50-800 mg BID on a 21/28 day and at 600 mg on a 28/28 day schedule. Plasma kynurenine and tryptophan were longitudinally evaluated and tumor assessments were performed. RESULTS: Patients (n = 22) received a median of 3 cycles of navoximod. No maximum tolerated dose was reached. One dose-limiting toxicity of Grade 4 lower gastrointestinal hemorrhage was reported. Adverse events (AEs) regardless of causality in ≥20% of patients included fatigue (59%), cough, decreased appetite, and pruritus (41% each), nausea (36%), and vomiting (27%). Grade ≥ 3 AEs occurred in 14/22 patients (64%), and were related to navoximod in two patients (9%). Navoximod was rapidly absorbed (Tmax ~ 1 h) and exhibited dose-proportional increases in exposure, with a half-life (t1/2 ~ 11 h) supportive of BID dosing. Navoximod transiently decreased plasma kynurenine from baseline levels with kinetics consistent with its half-life. Of efficacy-evaluable patients, 8 (36%) had stable disease and 10 (46%) had progressive disease. CONCLUSIONS: Navoximod was well-tolerated at doses up to 800 mg BID decreasing plasma kynurenine levels consistent with its half-life. Stable disease responses were observed. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02048709 .
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Inibidores Enzimáticos/uso terapêutico , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias/enzimologia , Recidiva , Resultado do TratamentoRESUMO
Taselisib is a potent and selective tumor growth inhibitor through PI3K pathway suppression. Thirty-four patients with locally advanced or metastatic solid tumors were treated (phase I study, modified 3+3 dose escalation; 5 cohorts; 3-16 mg taselisib once-daily capsule). Taselisib pharmacokinetics were dose-proportional; mean half-life was 40 hours. Frequent dose-dependent, treatment-related adverse events included diarrhea, hyperglycemia, decreased appetite, nausea, rash, stomatitis, and vomiting. At 12 and 16 mg dose levels, dose-limiting toxicities (DLT) were observed, with an accumulation of higher-grade adverse events after the cycle 1 DLT assessment window. Pharmacodynamic findings showed pathway inhibition at ≥3 mg in patient tumor samples, consistent with preclinical PIK3CA-mutant tumor xenograft models. Confirmed response rate was 36% for PIK3CA-mutant tumor patients with measurable disease [5/14: 4 breast cancer (3 patients at 12 mg); 1 non-small cell lung cancer], where responses started at 3 mg, and 0% in patients with tumors without known PIK3CA hotspot mutations (0/15).Significance: Preliminary data consistent with preclinical data indicate increased antitumor activity of taselisib in patients with PIK3CA-mutant tumors (in comparison with patients with tumors without known activating PIK3CA hotspot mutations) starting at the lowest dose tested of 3 mg, thereby supporting higher potency for taselisib against PIK3CA-mutant tumors. Cancer Discov; 7(7); 704-15. ©2017 AACR.See related commentary by Rodon and Tabernero, p. 666This article is highlighted in the In This Issue feature, p. 653.
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Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Imidazóis/administração & dosagem , Neoplasias/tratamento farmacológico , Oxazepinas/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Adulto , Idoso , Animais , Classe I de Fosfatidilinositol 3-Quinases/genética , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Imidazóis/efeitos adversos , Masculino , Camundongos , Pessoa de Meia-Idade , Mutação , Neoplasias/genética , Neoplasias/patologia , Oxazepinas/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
PURPOSE: This first-in-human dose-escalation trial evaluated the safety, tolerability, maximal-tolerated dose (MTD), dose-limiting toxicities (DLT), pharmacokinetics, pharmacodynamics, and preliminary clinical activity of pictilisib (GDC-0941), an oral, potent, and selective inhibitor of the class I phosphatidylinositol-3-kinases (PI3K). PATIENTS AND METHODS: Sixty patients with solid tumors received pictilisib at 14 dose levels from 15 to 450 mg once-daily, initially on days 1 to 21 every 28 days and later, using continuous dosing for selected dose levels. Pharmacodynamic studies incorporated (18)F-FDG-PET, and assessment of phosphorylated AKT and S6 ribosomal protein in platelet-rich plasma (PRP) and tumor tissue. RESULTS: Pictilisib was well tolerated. The most common toxicities were grade 1-2 nausea, rash, and fatigue, whereas the DLT was grade 3 maculopapular rash (450 mg, 2 of 3 patients; 330 mg, 1 of 7 patients). The pharmacokinetic profile was dose-proportional and supported once-daily dosing. Levels of phosphorylated serine-473 AKT were suppressed >90% in PRP at 3 hours after dose at the MTD and in tumor at pictilisib doses associated with AUC >20 h·µmol/L. Significant increase in plasma insulin and glucose levels, and >25% decrease in (18)F-FDG uptake by PET in 7 of 32 evaluable patients confirmed target modulation. A patient with V600E BRAF-mutant melanoma and another with platinum-refractory epithelial ovarian cancer exhibiting PTEN loss and PIK3CA amplification demonstrated partial response by RECIST and GCIG-CA125 criteria, respectively. CONCLUSION: Pictilisib was safely administered with a dose-proportional pharmacokinetic profile, on-target pharmacodynamic activity at dose levels ≥100 mg and signs of antitumor activity. The recommended phase II dose was continuous dosing at 330 mg once-daily.
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Indazóis/administração & dosagem , Neoplasias/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/administração & dosagem , Sulfonamidas/administração & dosagem , Administração Oral , Adulto , Idoso , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Indazóis/sangue , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/genética , Neoplasias/patologia , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/sangue , Inibidores de Proteínas Quinases/farmacocinética , Proteínas Proto-Oncogênicas B-raf/genética , Sulfonamidas/sangueRESUMO
To estimate the impact of early detection of cancer, knowledge of how quickly primary tumors grow and at what size they shed lethal metastases is critical. We developed a natural history model of cancer to estimate the probability of disease-specific cure as a function of tumor size, the tumor volume doubling time (TVDT), and disease-specific mortality reduction achievable by screening. The model was applied to non-small-cell lung carcinoma (NSCLC) and invasive ductal carcinoma (IDC), separately. Model parameter estimates were based on Surveillance Epidemiology and End Results (SEER) cancer registry datasets and validated on screening trials. Compared to IDC, NSCLC is estimated to have a lower probability of disease-specific cure at the same detected tumor size, shed lethal metastases at smaller sizes (median: 19 mm for IDC versus 8 mm for NSCLC), have a TVDT that is almost half as long (median: 252 days for IDC versus 134 days for NSCLC). Consequently, NSCLC is associated with a lower mortality reduction from screening at the same screen detection threshold and screening interval. In summary, using a similar natural history model of cancer, we quantify the disease-specific curability attributable to screening for breast cancer, and separately lung cancer, in terms of the TVDT and onset of lethal metastases.
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Neoplasias da Mama/patologia , Neoplasias Pulmonares/patologia , Modelos Biológicos , Idoso , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/prevenção & controle , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/prevenção & controle , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/prevenção & controle , Processos de Crescimento Celular/fisiologia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/prevenção & controle , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Programa de SEER , Estados Unidos/epidemiologiaRESUMO
The treatment of breast cancer involves a multi-disciplinary approach with radiation therapy playing a key role. Breast-conserving surgery has been an option for women with early-stage breast cancer for over two decades now. Multiple randomized trials now have demonstrated the efficacy of breast-conserving surgery followed by radiation therapy. With the advancements in breast imaging and the successful campaign for early detection of breast cancer, more women today are found to have early-stage small breast cancers. Patient factors (breast size, tumor location, history of prior radiation therapy, preexisting conditions such as collagen vascular disease, age, having prosthetically augmented breasts), pathological factors (margin status, tumor size, presence of extensive intraductal component requiring multiple surgical excisions), as well as patient preference are all taken into consideration prior to surgical management of breast cancer. Whole-breast fractionated radiation therapy between 5 and 7 weeks is considered as the standard of care treatment following breast-conserving surgery. However, new radiation treatment strategies have been developed in recent years to provide alternatives to the conventional 5-7 week whole-breast radiation therapy for some patients. Accelerated partial breast radiation therapy (APBI) was introduced because the frequency of breast recurrences outside of the surgical cavity has been shown to be low. This technique allows treatments to be delivered quicker (usually 1 week, twice daily) to a limited volume. Often times, this treatment involves the use of a brachytherapy applicator to be placed into the surgical cavity following breast-conserving surgery. Accelerated hypofractionated whole-breast irradiation may be another faster way to deliver radiation therapy following breast-conserving surgery. This journal article reviews the role of radiation therapy in women with early-stage breast cancer addressing patient selection in breast-conserving therapy, a review of pertinent trials in breast-conserving therapy, as well as the different treatment techniques available to women following breast-conserving surgery.
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OBJECTIVE: To discuss our experiences with the use of a supratip transposition flap to simultaneously correct pollybeak deformity and nasal tip dimpling. DESIGN: From April 1, 2007, through August 31, 2008, 10 Asian women with a contracted, short nose that exhibited nasal tip dimpling were retrospectively included in this study. By use of an open approach, the osteocartilaginous framework was elongated first. If the pollybeak and dimpling deformities of the nasal tip were found after the closure of the transcolumellar incision, a supratip transposition flap was designed to correct the combined deformities over the supratip and nasal tip areas. Finally, bilateral marginal incisions were closed. RESULTS: The follow-up period ranged from 2 to 16 months, with an average of 5 months. No immediate complications were noted in this small series. Four of 10 patients required minor flap revisions, with satisfactory results attained thereafter. All patients were satisfied with the aesthetic result after scar maturation. CONCLUSIONS: The use of the supratip transposition flap not only corrects pollybeak deformity but also resolves dimpled nasal tip depression. The techniques presented herein add to the armamentarium of revision rhinoplasty surgeons, especially those dedicated to the treatment of the Asian patient who undergoes rhinoplasty.
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Deformidades Adquiridas Nasais/cirurgia , Rinoplastia/métodos , Retalhos Cirúrgicos , Adulto , Povo Asiático , Feminino , Humanos , Pessoa de Meia-Idade , Fotografação , Estudos Retrospectivos , Resultado do TratamentoRESUMO
OBJECTIVES: The objective of this double-blind, randomized study was to determine the safety and efficacy of intracoronary radiation therapy (ICRT) with a dose of 17 Gray (Gy) compared to the currently recommended dose prescription of 14 Gy for the treatment of in-stent restenosis within bare metal stents. BACKGROUND: While gamma ICRT for in-stent restenosis has been proven efficacious, the optimal dose is unknown, and radiation failure due to recurrent neointimal hyperplasia remains a significant clinical problem for some patients. A higher radiation dose may improve outcomes, but may potentially increase adverse events. METHODS: Following coronary intervention, 336 patients with in-stent restenosis were randomly assigned to receive ICRT with either 14 Gy or 17 Gy at 2 mm from an 192-iridium source. RESULTS: At 8-month follow up, fewer patients in the 17 Gy group underwent target lesion revascularization (TLR = 15.2% versus 27.2%; p = 0.01), target vessel revascularization (21.3% versus 33.1%; p = 0.02), or reached the composite endpoint of death, myocardial infarction, thrombosis, or TLR (17.1% versus 28.4%; p = 0.02). There were no differences in late thrombosis or mortality between treatment groups. There was a strong trend toward reduced in-lesion late loss (0.36 +/- 0.63 mm vs. 0.51 +/- 0.64 mm; p = 0.09) and a significantly lower rate of binary restenosis (23.9% versus 38.1%; p = 0.031) in the high dose group. CONCLUSIONS: Gamma ICRT with 17 Gy is safe and, compared to 14 Gy, reduces recurrent stenosis and clinical events at 8-month follow up. An increase in the currently recommended gamma radiation dose prescription from 14 Gy to 17 Gy should be strongly considered.
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Reestenose Coronária/etiologia , Reestenose Coronária/radioterapia , Vasos Coronários/efeitos da radiação , Raios gama/uso terapêutico , Stents/efeitos adversos , Idoso , Relação Dose-Resposta à Radiação , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Metais , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Many biological databases contain a large number of variables, among which events of interest may be very infrequent. Using a single data mining method to analyze such databases may not find adequate predictors. The HIV Drug Resistance Database at Stanford University stores sequential HIV-1 genotype-test results on patients taking antiretroviral drugs. We have analyzed the infrequent event of gene mutation changes by combining three data mining methods. We first use association rule analysis to scan through the database and identify potentially interesting mutation patterns with relatively high frequency. Next, we use logistic regression and classification trees to further investigate these patterns by analyzing the relationship between treatment history and mutation changes. Although the AUC measures of the overall prediction is not very high, our approach can effectively identify strong predictors of mutation change and thus focus the analytic efforts of researchers in verifying these results.