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1.
J Cancer Educ ; 35(1): 105-111, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30467774

RESUMO

Radiation therapy (RT) is an effective treatment modality for hepatocellular carcinoma (HCC), but globally, it is underutilized. In Russia, practice patterns with regard to liver-directed radiation are unknown. Under the auspices of Russian Society of Clinical Oncology (RUSSCO), our team conducted an IRB-approved contouring workshop for Russian radiation oncologists. Pre- and post-workshop surveys were analyzed to determine baseline clinical experience and patterns of care for liver-directed RT among Russian providers. The effect of the contouring workshop on participants' knowledge was tested using mixed effects model. Forty pre-workshop and 24 post-workshop questionnaires were analyzable with a 100% response rate. Sixty percent of respondents had never evaluated a patient with HCC and only 8% (3 out of 40) reported treating an HCC patient with liver-directed RT. Nonetheless, 73% of respondents were comfortable offering liver-directed RT prior to the workshop. After the workshop, 85% of respondents felt comfortable treating a patient with HCC with liver-directed RT and 50% were comfortable recommending stereotactic body radiation therapy (SBRT). Measures of knowledge pertaining to evaluation of HCC patients and selection for appropriate liver-directed therapies were dramatically improved after the workshop. Liver-directed RT is not commonly used in Russia in the management of patients with HCC, and few centers are equipped for motion management. Our contouring workshop resulted in dramatically improved understanding of the evaluation and management of HCC patients. We recommend starting with a more protracted fractionated RT and building experience through attendance of additional educational activities, participation in multidisciplinary liver tumor boards, and prospective analysis of treatment toxicity and outcomes.


Assuntos
Carcinoma Hepatocelular/radioterapia , Competência Clínica , Neoplasias Hepáticas/radioterapia , Guias de Prática Clínica como Assunto/normas , Padrões de Prática Médica/normas , Radioterapia (Especialidade)/educação , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Gerenciamento Clínico , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Radio-Oncologistas , Radiocirurgia/métodos , Federação Russa/epidemiologia , Inquéritos e Questionários , Resultado do Tratamento
2.
Med Phys ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38452277

RESUMO

BACKGROUND: Biology-guided radiotherapy (BgRT) is a novel technology that uses positron emission tomography (PET) data to direct radiotherapy delivery in real-time. BgRT enables the precise delivery of radiation doses based on the PET signals emanating from PET-avid tumors on the fly. In this way, BgRT uniquely utilizes radiotracer uptake as a biological beacon for controlling and adjusting dose delivery in real-time to account for target motion. PURPOSE: To demonstrate using real-time PET for BgRT delivery on the RefleXion X1 radiotherapy machine. The X1 radiotherapy machine is a rotating ring-gantry radiotherapy system that generates a nominal 6MV photon beam, PET, and computed tomography (CT) components. The system utilizes emitted photons from PET-avid targets to deliver effective radiation beamlets or pulses to the tumor in real-time. METHODS: This study demonstrated a real-time PET BgRT delivery experiment under three scenarios. These scenarios included BgRT delivering to (S1 ) a static target in a homogeneous and heterogeneous environment, (S2 ) a static target with a hot avoidance structure and partial PET-avid target, and (S3 ) a moving target. The first step was to create stereotactic body radiotherapy (SBRT) and BgRT plans (offline PET data supported) using RefleXion's custom-built treatment planning system (TPS). Additionally, to create a BgRT plan using PET-guided delivery, the targets were filled with 18F-Fluorodeoxyglucose (FDG), which represents a tumor/target, that is, PET-avid. The background materials were created in the insert with homogeneous water medium (for S1 ) and heterogeneous water with styrofoam mesh medium. A heterogeneous background medium simulated soft tissue surrounding the tumor. The treatment plan was then delivered to the experimental setups using a pre-commercial version of the X1 machine. As a final step, the dosimetric accuracy for S1 and S2 was assessed using the ArcCheck analysis tool-the gamma criteria of 3%/3 mm. For S3 , the delivery dose was quantified using EBT-XD radiochromic film. The accuracy criteria were based on coverage, where 100% of the clinical target volume (CTV) receives at least 97% of the prescription dose, and the maximum dose in the CTV was ≤130% of the maximum planned dose (97 % ≤ CTV ≤ 130%). RESULTS: For the S1, both SBRT and BgRT deliveries had gamma pass rates greater than 95% (SBRT range: 96.9%-100%, BgRT range: 95.2%-98.9%), while in S2 , the gamma pass rate was 98% for SBRT and between 95.2% and 98.9% for BgRT plan delivering. For S3 , both SBRT and BgRT motion deliveries met CTV dose coverage requirements, with BgRT plans delivering a very high dose to the target. The CTV dose ranges were (a) SBRT:100.4%-120.4%, and (b) BgRT: 121.3%-139.9%. CONCLUSIONS: This phantom-based study demonstrated that PET signals from PET-avid tumors can be utilized to direct real-time dose delivery to the tumor accurately, which is comparable to the dosimetric accuracy of SBRT. Furthermore, BgRT delivered a PET-signal controlled dose to the moving target, equivalent to the dose distribution to the static target. A future study will compare the performance of BgRT with conventional image-guided radiotherapy.

3.
Int J Radiat Oncol Biol Phys ; 118(5): 1172-1180, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38147912

RESUMO

PURPOSE: Positron emission tomography (PET)-guided radiation therapy is a novel tracked dose delivery modality that uses real-time PET to guide radiation therapy beamlets. The BIOGUIDE-X study was performed with sequential cohorts of participants to (1) identify the fluorodeoxyglucose (FDG) dose for PET-guided therapy and (2) confirm that the emulated dose distribution was consistent with a physician-approved radiation therapy plan. METHODS AND MATERIALS: This prospective study included participants with at least 1 FDG-avid targetable primary or metastatic tumor (2-5 cm) in the lung or bone. For cohort I, a modified 3 + 3 design was used to determine the FDG dose that would result in adequate signal for PET-guided therapy. For cohort II, PET imaging data were collected on the X1 system before the first and last fractions among patients undergoing conventional stereotactic body radiation therapy. PET-guided therapy dose distributions were modeled on the patient's computed tomography anatomy using the collected PET data at each fraction as input to an "emulated delivery" and compared with the physician-approved plan. RESULTS: Cohort I demonstrated adequate FDG activity in 6 of 6 evaluable participants (100.0%) with the first injected dose level of 15 mCi FDG. In cohort II, 4 patients with lung tumors and 5 with bone tumors were enrolled, and evaluable emulated delivery data points were collected for 17 treatment fractions. Sixteen of the 17 emulated deliveries resulted in dose distributions that were accurate with respect to the approved PET-guided therapy plan. The 17th data point was just below the 95% threshold for accuracy (dose-volume histogram score = 94.6%). All emulated fluences were physically deliverable. No toxicities were attributed to multiple FDG administrations. CONCLUSIONS: PET-guided therapy is a novel radiation therapy modality in which a radiolabeled tumor can act as its own fiducial for radiation therapy targeting. Emulated therapy dose distributions calculated from continuously acquired real-time PET data were accurate and machine-deliverable in tumors that were 2 to 5 cm in size with adequate FDG signal characteristics.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Pulmonares , Humanos , Estudos Prospectivos , Tomografia por Emissão de Pósitrons , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Tomografia Computadorizada por Raios X/métodos , Compostos Radiofarmacêuticos
4.
Br J Radiol ; 96(1141): 20220387, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36317922

RESUMO

OBJECTIVES: In this study, we characterise the imaging-mode performance of the positron emission tomography (PET) subsystem of the RefleXion X1 machine using the NEMA NU-2 2018 standard. METHODS: The X1 machine consists of two symmetrically opposing 900 arcs of PET detectors incorporated into the architecture of a ring-gantry linear accelerator rotating up to 60 RPM. PET emissions from a tumour are detected by the PET detectors and used to guide the delivery of radiation beam. Imaging performance of the PET subsystem on X1 machine was evaluated based on sensitivity of the PET detectors, spatial resolution, count-loss performance, image quality, and daily system performance check. RESULTS: PET subsystem sensitivity was measured as 0.183 and 0.161 cps/kBq at the center and off-center positions, respectively. Spatial resolution: average FWHM values of 4.3, 5.1, and 6.7 mm for the point sources at 1, 10, and 20 cm off center, respectively were recorded. For count loss, max NECR: 2.63 kcps, max true coincidence rate: 5.56 kcps, and scatter fraction: 39.8%. The 10 mm sphere was not visible. Image-quality contrast values were: 29.6%, 64.9%, 66.5%, 81.8%, 81.2%, and background variability: 14.8%, 12.4%, 10.3%, 8.8%, 8.3%, for the 13, 17, 22, 28, 37 mm sphere sizes, respectively. CONCLUSIONS: When operating in an imaging mode, the spatial resolution and image contrast of the X1 PET subsystem were comparable to those of typical diagnostic imaging systems for large spheres, while the sensitivity and count rate were lower due to the significantly smaller PET detector area in the X1 system. Clinical efficacy when used in BgRT remains to be validated. ADVANCES IN KNOWLEDGE: This is the first performance evaluation of the PET subsystem on the novel BgRT machine. The dual arcs rotating PET subsystem on RefleXion X1 machine performance is comparable to those of the typical diagnostic PET system based on the spatial resolution and image contrast for larger spheres.


Assuntos
Biologia , Tomografia por Emissão de Pósitrons , Humanos , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos
5.
Clin Lung Cancer ; 23(4): 291-299, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35382980

RESUMO

BACKGROUND: First-line immunotherapy (IMT), with or without cytotoxic chemotherapy, is now recommended for most patients with advanced non-small cell lung cancer (NSCLC) with no targetable mutations. We reviewed outcomes for NSCLC patients treated with first-line IMT at our institution to test the hypothesis that measures of disease burden on staging FDG-PET/CT have prognostic value. MATERIALS AND METHODS: Patient, disease, and treatment details were collected. A gradient-based segmentation tool was used to delineate each PET-avid extracranial lesion. Numbers of extrathoracic lesions and metabolic tumor volumes were tabulated. Oligometastatic disease (OMD) was defined as having ≤3 extrathoracic lesions, with any number of thoracic lesions. Progression-free survival (PFS) and overall survival (OS) rates following initiation of IMT were evaluated using the Kaplan-Meier method, and predictors of PFS and OS were assessed using Cox proportional hazards models and logrank tests. RESULTS: One hundred twenty-four patients met inclusion criteria, and 1143 lesions were contoured. The presence of OMD was associated with favorable PFS (median 13.1 vs. 6.9 months; P = .016) and favorable OS (median 36.5 vs. 15.4 months; P = .002). In multivariable models, OMD was associated with favorable PFS (HR = 0.64; P = .034) and favorable OS (HR = 0.61; P = .063), and metabolic tumor volumes exceeding the cohort median (88 cc) was associated with inferior OS (HR = 1.85; P = .028). CONCLUSION: For advanced NSCLC patients receiving first-line IMT, the presence of extrathoracic OMD and low volumetric disease burden on PET are favorable prognostic factors that could be useful stratification factors in clinical trials and may influence clinical decisions about local and systemic therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/patologia , Fluordesoxiglucose F18 , Humanos , Imunoterapia , Neoplasias Pulmonares/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Estudos Retrospectivos
6.
Cancer ; 117(20): 4595-605, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21710653

RESUMO

BACKGROUND: Although postmastectomy radiation therapy (PMRT) improves survival for patients with high-risk breast cancer, previous literature suggested that it is underused. The impact of recent clinical guidelines on PMRT use is unknown. Accordingly, the authors used the Surveillance, Epidemiology, and End Results (SEER)-Medicare cohort to determine whether the use of PMRT has increased in response to evidence-based guidelines. METHODS: In total, 38,322 women aged ≥66 years who underwent mastectomy for invasive breast cancer between 1992 and 2005 were identified. Time trends in the receipt of PMRT for low-risk (T1/T2 N0), intermediate-risk (T1/T2 N1), and high-risk (T3/T4 and/or N2/N3) patients were characterized. Multivariate logistic regression identified risk factors for PMRT omission. RESULTS: The receipt of PMRT by patients with high-risk breast cancer increased from 36.5% (95% confidence interval, 26%-46.9%) to 57.7% (95% confidence interval, 46.9%-68.4%) between 1996 and 1998 with the publication of landmark clinical trials. However no further increase in PMRT use was observed between 1999 and 2005 despite publication of multiple guidelines endorsing its use; during this period, only 54.8% (2729 of 4978) of high-risk patients received PMRT. Within this high-risk group, patients with smaller tumors or less advanced lymph node disease were at risk for PMRT omission. CONCLUSIONS: After an initial increase in PMRT use in response to clinical trials, the use of PMRT did not increase further in response to guideline publication, and nearly 50% of patients with high-risk breast cancer still do not receive PMRT. Additional research is needed to determine how clinical guidelines can be used to bridge the gap between level I evidence and clinical practice.


Assuntos
Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/radioterapia , Carcinoma Ductal de Mama/cirurgia , Mastectomia , Guias de Prática Clínica como Assunto , Radioterapia Adjuvante/estatística & dados numéricos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Medicina Baseada em Evidências , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Metástase Linfática , Medicare , Análise Multivariada , Estadiamento de Neoplasias , Razão de Chances , Medição de Risco , Fatores de Risco , Programa de SEER , Estados Unidos/epidemiologia
7.
Clin Transl Radiat Oncol ; 29: 106-112, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34258399

RESUMO

This is a summary of the design and concept of the RefleXion X1, a system for biology-guided radiotherapy (BgRT). This system is a multi-modal tomography (PET, fan-beam kVCT, and MVD) treatment machine that utilizes imaging and therapy planes for optimized beam delivery of IMRT, SBRT, SRS, and BgRT radiotherapy regimens. For BgRT delivery specifically, annihilation photons emanating outward from a PET-avid tumor are used to guide the delivery of beamlets of radiation to the tumor at sub-second latency. With the integration of PET detectors, rapid beam-station delivery, real-time tracking, and high-frequency multi-leaf collimation, the BgRT system has the potential to deliver a highly conformal treatment to malignant lesions while minimizing dose to surrounding healthy tissues. Furthermore, the potential use of a single radiotracer injection to guide radiotherapy to multiple targets opens avenues for debulking in advanced and metastatic disease states.

8.
Br J Radiol ; 94(1117): 20200873, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33112685

RESUMO

The emerging biological understanding of metastatic cancer and proof-of-concept clinical trials suggest that debulking all gross disease holds great promise for improving patient outcomes. However, ablation of multiple targets with conventional external beam radiotherapy systems is burdensome, which limits investigation and utilization of complete metastatic ablation in the majority of patients with advanced disease. To overcome this logistical hurdle, technical innovation is necessary. Biology-guided radiotherapy (BgRT) is a new external beam radiotherapy delivery modality combining positron emission tomography-computed tomography (PET-CT) with a 6 MV linear accelerator. The key innovation is continuous response of the linear accelerator to outgoing tumor PET emissions with beamlets of radiotherapy at subsecond latency. This allows the deposited dose to track tumors in real time. Multiple new hardware and algorithmic advances further facilitate this low-latency feedback process. By transforming tumors into their own fiducials after intravenous injection of a radiotracer, BgRT has the potential to enable complete metastatic ablation in a manner efficient for a single patient and scalable to entire populations with metastatic disease. Future trends may further enhance the utility of BgRT in the clinic as this technology dovetails with other innovations in radiotherapy, including novel dose painting and fractionation schemes, radiomics, and new radiotracers.


Assuntos
Segunda Neoplasia Primária/radioterapia , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Fracionamento da Dose de Radiação , Humanos , Dosagem Radioterapêutica
9.
Plast Reconstr Surg Glob Open ; 9(11): e3904, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34745797

RESUMO

"Time burden" (time required during treatment) is relevant when choosing a local therapy option for early-stage breast cancer but has not been rigorously studied. We compared the time burden for three common local therapies for breast cancer: (1) lumpectomy plus whole-breast irradiation (Lump+WBI), (2) mastectomy without radiation or reconstruction (Mast alone), and (3) mastectomy without radiation but with reconstruction (Mast+Recon). METHODS: Using the MarketScan database, we identified 35,406 breast cancer patients treated from 2000 to 2011 with these local therapies. We quantified the total time burden as the sum of inpatient days (inpatient-days), outpatient days excluding radiation fractions (outpatient-days), and radiation fractions (radiation-days) in the first two years postdiagnosis. Multivariable regression evaluated the effect of local therapy on inpatient-days and outpatient-days adjusted for patient and treatment covariates. RESULTS: Adjusted mean number of inpatient-days was 1.0 for Lump+WBI, 2.0 for Mast alone, and 3.1 for Mast+Recon (P < 0.001). Adjusted mean number of outpatient-days was 42.9 for Lump+WBI, 42.2 for Mast alone, and 45.8 for Mast+Recon (P < 0.001). The mean number of radiation-days for Lump+WBI was 32.4. Compared with Mast+Recon (48.9 days), total adjusted time burden was 4.7 days shorter for Mast alone (44.2 days) and 27.4 days longer for Lump+WBI (76.3 days). However, use of a 15 fraction WBI regimen would reduce the time burden differential between Lump+WBI and Mast+Recon to just 10.0 days. CONCLUSIONS: Although Mast+Recon confers the highest inpatient and outpatient time burden, Lump+WBI carries the highest total time burden. Increased use of hypofractionation will reduce the total time burden for Lump+WBI.

10.
Ann Palliat Med ; 7(4): 368-372, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29860859

RESUMO

BACKGROUND: Radiation therapy (RT) can offer timely and effective treatment to oncology patients in the palliative setting. To date, there is sparse evidence investigating temporal relationships regarding the initiation of RT and subsequent hospital stay in the inpatient palliative setting. We aimed to assess whether times between admission, consultation, and initiation of treatment effected the length of hospital stay for patients receiving palliative radiation therapy (PRT). METHODS: This was a retrospective chart review of patients who received a consult for PRT from August 2014 to October 2016. All data was collected from a single community cancer center. Data including demographics, radiation treatment details, and temporal data (e.g., length of stay, time from admission to consult, etc.) were recorded. RESULTS: Of the 135 patients that received PRT, 60 of them were treated in the inpatient setting. The most common indications for PRT were pain (37%) and non-pain related neurologic symptoms (37%). The most common treatment sites were bone (58%), brain (22%), and lung (17%). There was a significant difference in duration of hospital stay between patients who were seen by palliative radiation oncology within two days versus greater than 2 days (P=0.02); and patients who were treated within 2 days of admission versus greater than 2 days (P=0.03). CONCLUSIONS: Further research is needed to establish causal temporal relationships in palliative radiation oncology. However, this data suggests that early involvement of the radiation oncology team is associated with a reduced length of hospital stay.


Assuntos
Tempo de Internação , Neoplasias/radioterapia , Cuidados Paliativos , Adulto , Idoso , Idoso de 80 Anos ou mais , Arizona , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Radioterapia (Especialidade) , Estudos Retrospectivos , Fatores de Tempo
11.
JNCI Cancer Spectr ; 2(2): pky022, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29905226

RESUMO

Given the recent emphasis on the totality of the diet by national guidelines, we examined the relationship between the quality of diet and overall and cancer-specific mortality among cancer survivors. From the Third National Health and Nutrition Examination Survey (NHANES III), 1191 participants diagnosed with cancer were identified. Healthy Eating Index (HEI) scores were utilized; higher HEI score indicated better adherence to dietary recommendations. During a median follow-up of 17.2 years, a total of 607 cancer-specific deaths occurred. A high-quality diet (highest-quartile HEI score) was associated with decreased risk of overall (hazard ratio [HR] = 0.59, 95% confidence interval [CI] = 0.45 to 0.77) and cancer-specific (HR = 0.35, 95% CI = 0.19 to 0.63) mortality when compared with a poor-quality diet (lowest-quartile HEI score). Among individual dietary components, the highest-quartile score for saturated fat intake was associated decreased cancer-specific mortality (HR = 0.55, 95% CI = 0.36 to 0.86). Our results highlight the importance of a "total diet" approach to improving survival among cancer patients.

12.
Pract Radiat Oncol ; 8(5): e329-e336, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29861349

RESUMO

BACKGROUND: In this study, we sought to examine the variation in intensity modulated radiation therapy (IMRT) use among radiation oncology providers. METHODS AND MATERIALS: The Medicare Physician and Other Supplier Public Use File was queried for radiation oncologists practicing during 2014. Healthcare Common Procedural Coding System code 77301 was designated as IMRT planning with metrics including number of total IMRT plans, rate of IMRT utilization, and number of IMRT plans per distinct beneficiary. RESULTS: Of 2759 radiation oncologists, the median number of total IMRT plans was 26 (mean, 33.4; standard deviation, 26.2; range, 11-321) with a median IMRT utilization rate of 36% (mean, 43%; standard deviation, 25%; range, 4% to 100%) and a median number of IMRT plans per beneficiary of 1.02 (mean, 1.07; range, 1.00-3.73). On multivariable analysis, increased IMRT utilization was associated with male sex, academic practice, technical fee billing, freestanding practice, practice in a county with 21 or more radiation oncologists, and practice in the southern United States (P < .05). The top 1% of users (28 providers) billed a mean 181 IMRT plans with an IMRT utilization rate of 66% and 1.52 IMRT plans per beneficiary. Of these 28 providers, 24 had billed technical fees, 25 practiced in freestanding clinics, and 20 practiced in the South. CONCLUSIONS: Technical fee billing, freestanding practice, male sex, and location in the South were associated with increased IMRT use. A small group of outliers shared several common demographic and practice-based characteristics.


Assuntos
Medicare/economia , Neoplasias/radioterapia , Padrões de Prática Médica/estatística & dados numéricos , Radioterapia (Especialidade)/estatística & dados numéricos , Radioterapia de Intensidade Modulada/estatística & dados numéricos , Feminino , Humanos , Reembolso de Seguro de Saúde/economia , Reembolso de Seguro de Saúde/estatística & dados numéricos , Masculino , Neoplasias/economia , Padrões de Prática Médica/economia , Radio-Oncologistas/economia , Radio-Oncologistas/estatística & dados numéricos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/economia , Fatores Sexuais , Estados Unidos
13.
J Oncol Pract ; 14(8): e513-e516, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30059272

RESUMO

PURPOSE: Shorter fractionation radiation regimens for palliation of bone metastases result in lower financial and social costs for patients and their caregivers and have similar efficacy as longer fractionation schedules, although practice patterns in the United States show poor adoption. We investigated whether prospective peer review can increase use of shorter fractionation schedules. METHODS: In June 2016, our practice mandated peer review of total dose and fractionation for all patients receiving palliative treatment during our weekly chart rounds. We used descriptive statistics and Fisher's exact test to compare lengths of treatment of uncomplicated bone metastases before and after implementation of the peer review process. RESULTS: Between July 2015 and December 2016, a total of 242 palliative treatment courses were delivered, including 105 courses before the peer review intervention and 137 after the intervention. We observed greater adoption of shorter fractionation regimens after the intervention. The use of 8 Gy in one fraction increased from 2.8% to 13.9% of cases postadoption. Likewise, the use of 20 Gy in five fractions increased from 25.7% to 32.8%. The use of 30 Gy in 10 fractions decreased from 55.2% to 47.4% ( P = .002), and the use of ≥ 11 fractions decreased from 16.2% before the intervention to 5.8% after ( P = .006). CONCLUSION: Prospective peer review of palliative regimens for bone metastases can lead to greater adoption of shorter palliative fractionation schedules in daily practice, in accordance with national guidelines. This simple intervention may therefore benefit patients and their caregivers as well as provide value to the health care system.


Assuntos
Neoplasias Ósseas/radioterapia , Cuidados Paliativos , Revisão por Pares , Neoplasias Ósseas/secundário , Fracionamento da Dose de Radiação , Humanos , Dor/radioterapia , Dosagem Radioterapêutica
14.
Physiol Genomics ; 30(1): 61-8, 2007 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-17327490

RESUMO

The cardiovascular restricted transcription factor CHF1/Hey2 has been previously shown to regulate the smooth muscle response to growth factors. To determine how CHF1/Hey2 affects the smooth muscle response to growth factors, we performed a genomic screen for transcripts that are differentially expressed in wild-type and knockout smooth muscle cells after stimulation with platelet-derived growth factor. We screened 45,101 probes representing >39,000 transcripts derived from at least 34,000 genes, at eight different time points. We analyzed the expression data utilizing an algorithm based on Bayesian statistics to derive the best polynomial clustering model to fit the expression data. We found that in a total of 9,827 transcripts the normalized ratio of knockout to wild-type expression diverged more than threefold from baseline in at least one time point, and these transcripts separated into 17 distinct clusters. Further analysis of each cluster revealed distinct alterations in gene expression patterns for immediate early genes, transcription factors, matrix metalloproteinases, signaling molecules, and other molecules important in vascular biology. Our findings demonstrate that CHF1/Hey2 profoundly affects vascular smooth muscle phenotype by altering both the absolute expression level of a variety of genes and the kinetics of growth factor-induced gene expression.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Miócitos de Músculo Liso/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Repressoras/genética , Transcrição Gênica/efeitos dos fármacos , Animais , Células Cultivadas , Camundongos , Camundongos Knockout , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Mutação , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Natl Cancer Inst ; 109(11)2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29059428

RESUMO

Background: Early-stage breast cancer is among the most prevalent and costly malignancies treated in the American health care system. Adjuvant radiotherapy after lumpectomy represents a substantial portion of breast cancer expenditures. The relative value of novel radiotherapeutic approaches such as intraoperative radiotherapy (IORT) and hypofractionated whole breast irradiation (HF-WBI) compared with conventionally fractionated whole breast irradiation (CF-WBI) is unknown. Therefore, we used prospectively collected outcomes from randomized clinical trials (RCTs) to compare the cost-effectiveness of these approaches. Methods: We constructed a decision-analytic model that followed women who were treated with lumpectomy for early-stage breast cancer. Recurrence, mortality, complication rates, and utilities (five-year radiation-associated quality of life scores), were extracted from RCTs. Costs were based on Medicare reimbursement rates. Cost-effectiveness from societal and health care sector perspectives was estimated considering two scenarios-the first assumes that radiation-associated disutility persists five years after treatment, and the second assumes that disutility discontinues. Lifetime outcomes were summarized using incremental cost-effectiveness ratios (ICERs). Deterministic and probabilistic sensitivity analyses evaluated the robustness of the results. Results: HF-WBI dominated CF-WBI (ie, resulted in higher quality-adjusted life-years [QALYs] and lower cost) in all scenarios. HF-WBI also had a greater likelihood of cost-effectiveness compared with IORT; under a societal perspective that assumes that radiation-associated disutility persists, HF-WBI results in an ICER of $17 024 per QALY compared with IORT with a probability of cost-effectiveness of 80% at the $100 000 per QALY willingness-to-pay threshold. If radiation-associated disutility is assumed to discontinue, the ICER is lower ($11 461/QALY), resulting in an even higher (83%) probability of relative cost-effectiveness. The ICER was most sensitive to the probability of metastasis and treatment cost. Conclusions: For women with early-stage breast cancer requiring adjuvant radiotherapy, HF-WBI is cost-effective compared with CF-WBI and IORT.


Assuntos
Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Análise Custo-Benefício , Anos de Vida Ajustados por Qualidade de Vida , Idoso , Neoplasias da Mama/cirurgia , Feminino , Humanos , Cuidados Intraoperatórios , Cadeias de Markov , Mastectomia Segmentar , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Qualidade de Vida , Hipofracionamento da Dose de Radiação , Radioterapia/economia , Radioterapia Adjuvante/economia , Ensaios Clínicos Controlados Aleatórios como Assunto , Sensibilidade e Especificidade
16.
J Natl Cancer Inst ; 109(1)2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27678203

RESUMO

Background: Guideline-concordant local therapy options for early breast cancer include lumpectomy plus whole breast irradiation (Lump+WBI), lumpectomy plus brachytherapy, mastectomy alone, mastectomy plus reconstruction, and, in older women, lumpectomy alone. We performed a comparative examination of each treatment's complications and cost to assess their relative values. Methods: Using the MarketScan database of younger women with private insurance and the SEER-Medicare database of older women with public insurance, we identified 105 211 women with early breast cancer diagnosed between 2000 and 2011. We used diagnosis and procedural codes to identify treatment complications within 24 months of diagnosis and compared complications by treatment using two-sided logistic regression. Mean total and complication-related cost, relative to Lump+WBI, were calculated from a payer's perspective and adjusted for differences in covariables using linear regression. All statistical tests were two-sided. Results: Lump+WBI was the most commonly used treatment. Mastectomy plus reconstruction was associated with nearly twice the complication risk of Lump+WBI (Marketscan: 54.3% vs 29.6%, relative risk [RR] = 1.87, 95% confidence interval [CI] = 1.82 to 1.91, P < .001; SEER-Medicare: 66.1% vs 37.6%, RR = 1.75, 95% CI = 1.69 to 1.82, P < .001) and was also associated with higher adjusted total cost (Marketscan: $22 481 greater than Lump+WBI; SEER-Medicare: $1748 greater) and complication-related cost (Marketscan: $9017 greater; SEER-Medicare: $2092 greater). Brachytherapy had modestly higher total cost and complications than WBI. Lumpectomy alone entailed lower cost and complications in the SEER-Medicare cohort only. Conclusions: Mastectomy plus reconstruction results in substantially higher complications and cost than other guideline-concordant treatment options for early breast cancer. These findings are relevant to patients evaluating their local therapy options and to value-based population health management.

17.
Pract Radiat Oncol ; 7(5): 295-301, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28596092

RESUMO

PURPOSE: This guideline presents evidence-based recommendations for stereotactic body radiation therapy (SBRT) in challenging clinical scenarios in early-stage non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: The American Society for Radiation Oncology convened a task force to perform a systematic literature review on 4 key questions addressing: (1) application of SBRT to operable patients; (2) appropriate use of SBRT in tumors that are centrally located, large, multifocal, or unbiopsied; (3) individual tailoring of SBRT in "high-risk" clinical scenarios; and (4) SBRT as salvage therapy after recurrence. Guideline recommendations were created using a predefined consensus-building methodology supported by American Society for Radiation Oncology-approved tools for grading evidence quality and recommendation strength. RESULTS: Although few randomized trials have been completed for SBRT, strong consensus recommendations based on extensive, consistent publications were generated for several questions, including recommendations for fractionation for central tumors and surgery versus SBRT in standard-risk medically operable patients with early-stage NSCLC. Lower quality evidence led to conditional recommendations on use of SBRT for tumors >5 cm, patients with prior pneumonectomy, T3 tumors with chest wall invasion, synchronous multiple primary lung cancer, and as a salvage therapy after prior radiation therapy. These areas of moderate- and low-quality evidence highlight the importance of clinical trial enrollment as well as the role of prospective data registries. CONCLUSIONS: SBRT has an important role to play in treating early-stage NSCLC, particularly for medically inoperable patients with limited other treatment options. Shared decision-making with patients should be performed in all cases to ensure the patient understands the risks related to SBRT, the side effects, and the alternative treatments available.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Medicina Baseada em Evidências/normas , Neoplasias Pulmonares/terapia , Recidiva Local de Neoplasia/radioterapia , Radiocirurgia/normas , Carcinoma Pulmonar de Células não Pequenas/patologia , Tomada de Decisão Clínica/métodos , Consenso , Fracionamento da Dose de Radiação , Humanos , Neoplasias Pulmonares/patologia , Estadiamento de Neoplasias , Seleção de Pacientes , Pneumonectomia , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Radio-Oncologistas/psicologia , Radio-Oncologistas/normas , Radioterapia (Especialidade)/normas , Radiocirurgia/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia de Salvação/efeitos adversos , Terapia de Salvação/métodos , Terapia de Salvação/normas
18.
Brachytherapy ; 16(1): 223-229, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27908679

RESUMO

PURPOSE: The aim of this study was to define current patterns of care among radiation oncologists who use skin surface brachytherapy for the treatment of cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) in academic and community settings. METHODS AND MATERIALS: A 30-question electronic survey was administered to clinician members of the American Brachytherapy Society. The respondents were asked to provide details regarding their clinical practice and their approach to skin surface brachytherapy. RESULTS: A total of 16 surveys were returned. Among the respondents, aggregate experience varied from 8 to 1800 cases. Most preferred brachytherapy over external beam radiation because of shorter treatment course, conformality of treatment for irregular or curved targets, and shallow dose deposition. Of the total, 60% of respondents routinely estimated lesion depth via ultrasound before initiating treatment. Treatment margin on gross disease varied widely (range, 3-15 mm; median, 5 mm). Hypofractionation was the preferred dose schedule. Prescribed doses ranged from 30 Gy in five fractions to 64 Gy in 32 fractions (EQD2, 40 Gy-65 Gy). There was a tendency to increase the number of fractions for larger targets, although some used the same fractionation regardless of anatomic location or lesion size. There was no consensus on dosimetric constraints, and some respondents reported cases of severe toxicity, particularly when treating the pretibial skin. CONCLUSIONS: This pattern of care study suggests that skin brachytherapy can be a convenient and safe tool for treatment of BCC and cSCC. Prospective trials and the development of expert consensus guidelines would be beneficial for optimizing skin surface brachytherapy and reducing practice variation.


Assuntos
Braquiterapia/métodos , Carcinoma Basocelular/radioterapia , Carcinoma de Células Escamosas/radioterapia , Padrões de Prática Médica/estatística & dados numéricos , Radio-Oncologistas , Neoplasias Cutâneas/radioterapia , Braquiterapia/instrumentação , Fracionamento da Dose de Radiação , Humanos , Estudos Prospectivos , Inquéritos e Questionários
20.
Int J Radiat Oncol Biol Phys ; 95(2): 605-16, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27034179

RESUMO

PURPOSE: Older women with early-stage disease constitute the most rapidly growing breast cancer demographic, yet it is not known which local therapy strategies are most favored by this population in the current era. Understanding utilization trends and cost of local therapy is important for informing the design of bundled payment models as payers migrate away from fee-for-service models. We therefore used the Surveillance, Epidemiology, and End Results Medicare database to determine patterns of care and costs for local therapy among older women with breast cancer. METHODS AND MATERIALS: Treatment strategy and covariables were determined in 55,327 women age ≥66 with Tis-T2N0-1M0 breast cancer who underwent local therapy between 2000 and 2008. Trends in local therapy were characterized using Joinpoint. Polychotomous logistic regression determined predictors of local therapy. The median aggregate cost over the first 24 months after diagnosis was determined from Medicare claims through 2010 and reported in 2014 dollars. RESULTS: The median age was 75. Local therapy distribution was as follows: 27,896 (50.3%) lumpectomy with external beam radiation, 18,356 (33.1%) mastectomy alone, 6159 (11.1%) lumpectomy alone, 1488 (2.7%) mastectomy with reconstruction, and 1455 (2.6%) lumpectomy with brachytherapy. Mastectomy alone declined from 39.0% in 2000 to 28.2% in 2008, and the use of breast conserving local therapies rose from 58.7% to 68.2%. Mastectomy with reconstruction was more common among the youngest, healthiest patients, whereas mastectomy alone was more common among patients living in rural low-income regions. By 2008, the costs were $36,749 for lumpectomy with brachytherapy, $35,030 for mastectomy with reconstruction, $31,388 for lumpectomy with external beam radiation, $21,993 for mastectomy alone, and $19,287 for lumpectomy alone. CONCLUSIONS: The use of mastectomy alone in older women declined in favor of breast conserving strategies between 2000 and 2008. Using these cost estimates, price points for local therapy bundles can be constructed to incentivize the treatment strategies that confer the highest value.


Assuntos
Neoplasias da Mama/terapia , Custos de Cuidados de Saúde , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/economia , Terapia Combinada , Feminino , Humanos , Modelos Logísticos , Mastectomia/economia , Mastectomia Segmentar/economia , Medicare , Receptores de Estrogênio/análise , Programa de SEER , Estados Unidos
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