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BACKGROUND: Soft tissue sarcomas (STS), have significant inter- and intra-tumoral heterogeneity, with poor response to standard neoadjuvant radiotherapy (RT). Achieving a favorable pathologic response (FPR ≥ 95%) from RT is associated with improved patient outcome. Genomic adjusted radiation dose (GARD), a radiation-specific metric that quantifies the expected RT treatment effect as a function of tumor dose and genomics, proposed that STS is significantly underdosed. STS have significant radiomic heterogeneity, where radiomic habitats can delineate regions of intra-tumoral hypoxia and radioresistance. We designed a novel clinical trial, Habitat Escalated Adaptive Therapy (HEAT), utilizing radiomic habitats to identify areas of radioresistance within the tumor and targeting them with GARD-optimized doses, to improve FPR in high-grade STS. METHODS: Phase 2 non-randomized single-arm clinical trial includes non-metastatic, resectable high-grade STS patients. Pre-treatment multiparametric MRIs (mpMRI) delineate three distinct intra-tumoral habitats based on apparent diffusion coefficient (ADC) and dynamic contrast enhanced (DCE) sequences. GARD estimates that simultaneous integrated boost (SIB) doses of 70 and 60 Gy in 25 fractions to the highest and intermediate radioresistant habitats, while the remaining volume receives standard 50 Gy, would lead to a > 3 fold FPR increase to 24%. Pre-treatment CT guided biopsies of each habitat along with clip placement will be performed for pathologic evaluation, future genomic studies, and response assessment. An mpMRI taken between weeks two and three of treatment will be used for biological plan adaptation to account for tumor response, in addition to an mpMRI after the completion of radiotherapy in addition to pathologic response, toxicity, radiomic response, disease control, and survival will be evaluated as secondary endpoints. Furthermore, liquid biopsy will be performed with mpMRI for future ancillary studies. DISCUSSION: This is the first clinical trial to test a novel genomic-based RT dose optimization (GARD) and to utilize radiomic habitats to identify and target radioresistance regions, as a strategy to improve the outcome of RT-treated STS patients. Its success could usher in a new phase in radiation oncology, integrating genomic and radiomic insights into clinical practice and trial designs, and may reveal new radiomic and genomic biomarkers, refining personalized treatment strategies for STS. TRIAL REGISTRATION: NCT05301283. TRIAL STATUS: The trial started recruitment on March 17, 2022.
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Temperatura Alta , Sarcoma , Humanos , Radiômica , Sarcoma/diagnóstico por imagem , Sarcoma/genética , Sarcoma/radioterapia , Genômica , Doses de RadiaçãoRESUMO
OBJECTIVES: Stereotactic body radiotherapy (SBRT) is widely used for localized prostate cancer and implementation of MR-guided radiotherapy has the advantage of tighter margins and improved sparing of organs at risk. Here we evaluate outcomes and time required to treat using non-adaptive MR-guided SBRT (MRgSBRT) for localized prostate cancer at our institution. METHODS: From 9/2019 to 11/2021 we conducted a retrospective review of 80 consecutive patients who were treated with MRgSBRT to the prostate. Patients included low (LR) (5%), favorable intermediate (FIR) (40%), unfavorable intermediate (UIR) (49%), and high risk (HR) (6%). Short-term androgen deprivation therapy was used in 32% of patients. Target volumes included prostate gland and proximal seminal vesicles with an isotropic 3 mm margin. Treatment was prescribed to 36.25 Gy in 5 fractions every other day with urethral sparing. Hydrogel spacer was used in 18% of patients. Time on the linac was recorded as beam on time (BOT) plus total treatment time (TTT) including gating. Analyzed outcomes included PSA response and patient reported outcomes scored by the American Urological Association (AUA) questionnaire and toxicity per CTCAE v5. General linear regression model was used to analyze factors affecting PSA and AUA in longitudinal follow up, and chi-square test was used to assess factors affecting toxicity. RESULTS: Median follow up was 19.3 months (3.8 - 36.6). Median BOT was 4.6 min (2.6 - 7.2) with a median TTT of 11 min (7.6 - 15.8). Pre-treatment vs post-RT median PSA was 6.36 (2.20 - 19.6) vs 0.85 (0.19 - 3.6), respectively (P < 0.001). PSA decrease differed significantly when patients were stratified by risk category, favoring LR/FIR vs UIF/HR group (P = 0.019). Four (5%) patients experienced a biochemical failure (BCF), with a median time to BCF of 20.4 months (7.9 - 34.5). Median biochemical failure free survival (BCFFS) was not reached, with 2-yr and 4-yr BCFFS of 97.1% and 72.1%, respectively. Patients with LR/FIR disease had 100% 2-yr and 4-yr BCFFS, whereas patients with UIF/HR had 95% and 41% 2-yr and 4-yr BCFFS (P = 0.05). Mean pre-treatment AUA was 7.3 (1 - 25) vs 11.3 (1 - 26) at first follow-up; however, AUA normalized to baseline over time. Urethral Dmax ≥35 Gy trended to lower AUA score at all follow-ups (P = 0.07). Forty-one (51%) patients reported grade 1-2 genitourinary toxicities at the 1 month follow up. Grade 3 toxicity (proctitis) was noted in 1 patient. There was no decrease in any grade rectal toxicity with use of hydrogel spacer (3 vs 6, P = 0.2). No grade ≥4 toxicities was observed. CONCLUSIONS: MRgSBRT has the potential for treatment adaptation but this comes at the cost of increased resource utilization. Our experience with non-adaptive MRgSBRT of the prostate highlights its short treatment times as well as efficacy with good PSA control and low toxicity profile.
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Neoplasias da Próstata , Radiocirurgia , Radioterapia Guiada por Imagem , Humanos , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Radiocirurgia/métodos , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Radioterapia Guiada por Imagem/métodos , Resultado do Tratamento , Imageamento por Ressonância Magnética , Idoso de 80 Anos ou mais , Antígeno Prostático Específico/sangueRESUMO
Leading successful change efforts first requires assessment of the "before change" environment and culture. At our institution, the radiation oncology (RO) residents follow a longitudinal didactic learning program consisting of weekly 1-h lectures, case conferences, and journal clubs. The resident didactic education series format has not changed since its inception over 10 years ago. We evaluated the perceptions of current residents and faculty about the effectiveness of the curriculum in its present form. Two parallel surveys were designed, one each for residents and attendings, to assess current attitudes regarding the effectiveness and need for change in the RO residency curriculum, specifically the traditional didactic lectures, the journal club sessions, and the case conferences. We also investigated perceived levels of engagement among residents and faculty, whether self-assessments would be useful to increase material retention, and how often the content of didactic lectures is updated. Surveys were distributed individually to each resident (N = 10) and attending (N = 24) either in-person or via Zoom. Following completion of the survey, respondents were informally interviewed about their perspectives on the curriculum's strengths and weaknesses. Compared to 46% of attendings, 80% of RO residents believed that the curriculum should be changed. Twenty percent of residents felt that the traditional didactic lectures were effective in preparing them to manage patients in the clinic, compared to 74% of attendings. Similarly, 10% of residents felt that the journal club sessions were effective vs. 42% of attendings. Finally, 40% of residents felt that the case conferences were effective vs. 67% of attendings. Overall, most respondents (56%) favored change in the curriculum. Our results suggest that the perceptions of the residents did not align with those of the attending physicians with respect to the effectiveness of the curriculum and the need for change. The discrepancies between resident and faculty views highlight the importance of a dedicated change management effort to mitigate this gap. Based on this project, we plan to propose recommended changes in structure to the residency program directors. Main changes would be to increase the interactive nature of the course material, incorporate more ways to increase faculty engagement, and consider self-assessment questions to promote retention. Once we get approval from the residency program leadership, we will follow Kotter's "Eight steps to transforming your organization" to ensure the highest potential for faculty to accept the expectations of a new curriculum.
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PURPOSE/OBJECTIVE(S): Whole brain radiotherapy with hippocampal avoidance (HA-WBRT) is a technique utilized to treat metastatic brain disease while preserving memory and neurocognitive function. We hypothesized that the treatment planning and delivery of HA-WBRT plans is feasible with an MRI-guided linear accelerator (linac) and compared plan results with clinical non-MRI-guided C-Arm linac plans. MATERIALS/METHODS: Twelve HA-WBRT patients treated on a non-MRI-guided C-Arm linac were selected for retrospective analysis. Treatment plans were developed using a 0.35T MRI-guided linac system for comparison to clinical plans. Treatment planning goals were defined as provided in the Phase II Trial NRG CC001. MRI-guided radiotherapy (MRgRT) treatment plans were developed by a dosimetrist and compared with clinical plans. quality assurance (QA) plans were generated and delivered on the MRI-guided linac to a cylindrical diode detector array. Planning target volume (PTV) coverage was normalized to â¼95% to provide a control point for comparison of dose to the organs at risk. RESULTS: MRgRT plans were deliverable and met all clinical goals. Mean values demonstrated that the clinical plans were less heterogeneous than MRgRT plans with mean PTV V37.5 Gy of 0.00% and 0.03% (p = 0.013), respectively. Average hippocampi maximum doses were 14.19 ± 1.29 Gy and 15.00 ± 1.51 Gy, respectively. The gamma analysis comparing planned and measured doses resulted in a mean of 99.9% ± 0.12% of passing points (3%/2mm criteria). MRgRT plans had an average of 38.33 beams with average total delivery time and beam-on time of 13.7 (11.2-17.5) min and 4.1 (3.2-5.4) min, respectively. Clinical plan delivery times ranged from 3 to 7 min depending on the number of noncoplanar arcs. Planning time between the clinical and MRgRT plans was comparable. CONCLUSION: This study demonstrates that HA-WBRT can be treated using an MRI-guided linear accelerator with comparable treatment plan quality and delivery accuracy.
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Radioterapia de Intensidade Modulada , Ensaios Clínicos Fase II como Assunto , Estudos de Viabilidade , Hipocampo , Humanos , Imageamento por Ressonância Magnética , Aceleradores de Partículas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Estudos RetrospectivosRESUMO
The increasing complexity of healthcare emphasizes the need for continued physician leadership and leadership training. This study aims to determine baseline attitudes toward the perceptions and utility of a leadership development curriculum (LDC) for radiation oncology (RO) residents. A novel longitudinal LDC was implemented for RO residents at our institution from 2018 to 2019. Prior to the curriculum, current and past residents in our institution's RO residency program were surveyed on their attitudes towards leadership in healthcare, emotional intelligence competencies, and leadership training interests. After the completion of the LDC, a post-curriculum survey was forwarded to current residents. The response rate was 84% (21 of 24) for the baseline survey and 90% (9 of 10) for the post-curriculum survey. Having a leadership training curriculum during residency was rated as extremely useful, with top training interests involving leading clinical teams, effective communication strategies, and conflict management. After the LDC, the residents reported high satisfaction with the curriculum and utilization of leadership training into their daily work. Our LDC demonstrates significant potential to engage trainees and improve their leadership skills at the graduate medical education level.
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Internato e Residência , Radioterapia (Especialidade) , Currículo , Educação de Pós-Graduação em Medicina , Humanos , Liderança , Radioterapia (Especialidade)/educaçãoRESUMO
External beam radiotherapy (XRT) is a widely used cancer treatment, yet responses vary dramatically among patients. These differences are not accounted for in clinical practice, partly due to a lack of sensitive early response biomarkers. We hypothesize that quantitative magnetic resonance imaging (MRI) measures reflecting tumor heterogeneity can provide a sensitive and robust biomarker of early XRT response. MRI T2 mapping was performed every 72 hours following 10 Gy dose XRT in two models of pancreatic cancer propagated in the hind limb of mice. Interquartile range (IQR) of tumor T2 was presented as a potential biomarker of radiotherapy response compared with tumor growth kinetics, and biological validation was performed through quantitative histology analysis. Quantification of tumor T2 IQR showed sensitivity for detection of XRT-induced tumor changes 72 hours after treatment, outperforming T2-weighted and diffusion-weighted MRI, with very good robustness. Histological comparison revealed that T2 IQR provides a measure of spatial heterogeneity in tumor cell density, related to radiation-induced necrosis. Early IQR changes were found to correlate to subsequent tumor volume changes, indicating promise for treatment response prediction. Our preclinical findings indicate that spatial heterogeneity analysis of T2 MRI can provide a translatable method for early radiotherapy response assessment. We propose that the method may in future be applied for personalization of radiotherapy through adaptive treatment paradigms.
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Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Animais , Linhagem Celular Tumoral , Camundongos Endogâmicos NOD , Camundongos SCID , Necrose , Neoplasias/patologia , Reprodutibilidade dos Testes , Carga TumoralRESUMO
Radiation training programs are designed to prepare graduates for independent practice, with metrics in place to assess appropriateness of clinical decision-making. Here, we investigated the self-assessed preparedness of US graduates during the transition to independent practice.An anonymous, Internet-based survey was distributed to recent graduates of radiation oncology residencies (2016-2017). A Likert scale was used to assess comfort with various aspects of practice, as well as "time" to development of comfort in independent practice.Responses were obtained from 70/210 (33%), the majority reported training in programs with 5-8 residents (n = 35). Most (77%) reported designing between 500 and 900 treatment plans during training (n = 54). Only 41% of respondents reported the opportunity to review treatment plans and make decisions about safety/adequacy without attending input > 50% of the time (n = 29). Thirty percent of residents reported being responsible for seeing/managing on-treatment visits (OTVs) ≤ 75% of the time. Aspects with which practitioners reported the least comfort were understanding of billing/application to practice (2.43, IQR 2-3), orthovoltage (superficial radiation) setup and field design (2.57, IQR 1-4), and planning/delivery of prostate implants (2.82, IQR 2-4). Increased mean comfort levels were reported by those designing > 700 treatment plans in training as well as those reporting an opportunity to evaluate plans and make clinical decisions prior to attending input > 50% of the time during residency. Comfort with the delivery of stereotactic body radiation (SBRT) correlated with caseload for liver, spine, prostate, and CNS disease sites but not lung.Variations in training experiences exist across institutions. Here, a lower than expected number of residents reported seeing/managing OTVs as well as reviewing treatment plans prior to attending input during training. Overall comfort was correlated with case volume and opportunities to independently review treatment plans prior to attending input. These data highlight areas of opportunity for improving resident education with implications for ease of transition to independent clinical practice.
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Internato e Residência , Radioterapia (Especialidade) , Competência Clínica , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
MRI-guided radiotherapy is a novel and rapidly evolving technology that might enhance the risk-benefit ratio. Through direct visualisation of the tumour and the nearby healthy tissues, the radiation oncologist can deliver highly accurate treatment even to mobile targets. Each individual treatment can be customised to changing anatomy, potentially reducing the risk of radiation-related toxicities while simultaneously increasing the dose delivered to the tumour. MRI-guided radiotherapy offers a new tool for the radiation oncologist, and creates an opportunity to achieve durable local control of liver tumours that might not otherwise be possible. Future work will allow us to expand the population eligible for curative-intent radiotherapy, optimise and customise radiation doses to specific tumours, and hopefully create opportunities for improving outcomes through machine learning and radiomics-based approaches. This Review outlines the current and future applications for MRI-guided radiotherapy with respect to metastatic and primary liver cancers.
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Neoplasias Hepáticas/radioterapia , Imageamento por Ressonância Magnética/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Dosagem RadioterapêuticaRESUMO
Emergence of the COVID-19 crisis has catalyzed rapid paradigm shifts throughout medicine. Even after the initial wave of the virus subsides, a wholesale return to the prior status quo is not prudent. As a specialty that values the proper application of new technology, radiation oncology should strive to be at the forefront of harnessing telehealth as an important tool to further optimize patient care. We remain cognizant that telehealth cannot and should not be a comprehensive replacement for in-person patient visits because it is not a one for one replacement, dependent on the intention of the visit and patient preference. However, we envision the opportunity for the virtual patient "room" where multidisciplinary care may take place from every specialty. How we adapt is not an inevitability, but instead, an opportunity to shape the ideal image of our new normal through the choices that we make. We have made great strides toward genuine multidisciplinary patient-centered care, but the continued use of telehealth and virtual visits can bring us closer to optimally arranging the spokes of the provider team members around the central hub of the patient as we progress down the road through treatment.
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Betacoronavirus , Infecções por Coronavirus/epidemiologia , Neoplasias/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde , Quartos de Pacientes/organização & administração , Pneumonia Viral/epidemiologia , Telemedicina/métodos , Realidade Virtual , COVID-19 , Comorbidade , Humanos , Neoplasias/epidemiologia , Pandemias , Satisfação do Paciente , SARS-CoV-2RESUMO
The landscape of non-small cell lung cancer (NSCLC) treatment has rapidly evolved over the past decade. This is exemplified by the use of molecular targeted agents, immunotherapies, and newer technologies such as stereotactic body radiotherapy (SBRT). As the translation of preclinical discoveries into clinical practice continues, the effective dissemination and implementation of evidence-based treatment of NSCLC will remain a foremost challenge for oncologists. To further extend evidence-based medicine into the community setting, community oncologists are being engaged on multiple fronts including leadership and participation in national clinical trials and utilization of internet-based resources.
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Carcinoma Pulmonar de Células não Pequenas/radioterapia , Medicina Baseada em Evidências , Radiocirurgia , Pesquisa Translacional Biomédica , Carcinoma Pulmonar de Células não Pequenas/patologia , Gerenciamento Clínico , HumanosRESUMO
BACKGROUND: The NIH and Department of Health & Human Services recommend online patient information (OPI) be written at a sixth grade level. We used a panel of readability analyses to assess OPI from NCI-Designated Cancer Center (NCIDCC) Web sites. METHODS: Cancer.gov was used to identify 68 NCIDCC Web sites from which we collected both general OPI and OPI specific to breast, prostate, lung, and colon cancers. This text was analyzed by 10 commonly used readability tests: the New Dale-Chall Readability Formula, Flesch Reading Ease scale, Flesch-Kinaid Grade Level, FORCAST scale, Fry Readability Graph, Simple Measure of Gobbledygook test, Gunning Frequency of Gobbledygook index, New Fog Count, Raygor Readability Estimate Graph, and Coleman-Liau Index. We tested the hypothesis that the readability of NCIDCC OPI was written at the sixth grade level. Secondary analyses were performed to compare readability of OPI between comprehensive and noncomprehensive centers, by region, and to OPI produced by the American Cancer Society (ACS). RESULTS: A mean of 30,507 words from 40 comprehensive and 18 noncomprehensive NCIDCCs was analyzed (7 nonclinical and 3 without appropriate OPI were excluded). Using a composite grade level score, the mean readability score of 12.46 (ie, college level: 95% CI, 12.13-12.79) was significantly greater than the target grade level of 6 (middle-school: P<.001). No difference between comprehensive and noncomprehensive centers was identified. Regional differences were identified in 4 of the 10 readability metrics (P<.05). ACS OPI provides easier language, at the seventh to ninth grade level, across all tests (P<.01). CONCLUSIONS: OPI from NCIDCC Web sites is more complex than recommended for the average patient.
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Internet/normas , Educação de Pacientes como Assunto/métodos , Compreensão , Humanos , National Cancer Institute (U.S.) , Estados UnidosRESUMO
The incidence of skin cancer among U.S. Hispanics increased 1.3% annually from 1992 to 2008. However, little research has focused on skin cancer prevention among the rapidly growing Hispanic population. In this study, we examined theory-driven, psychosocial correlates of sun protection behaviors in a population-based sample of 787 Hispanic adults (49.6% female, mean age = 41.0 years) residing in five southern or western U.S. states. Participants completed an English- or Spanish-language online survey in September 2011. The outcomes of focus were sunscreen use, shade seeking, and use of sun protective clothing. The correlates included suntan benefits, sun protection benefits and barriers, skin color preference, perceived natural skin protection, photo-aging concerns, perceived skin cancer risk, skin cancer worry, skin cancer fatalism, and sun protection descriptive norms. Results of multiple linear regression analyses revealed the following: sun protection barriers were negatively associated with each outcome; descriptive norms were positively associated with each outcome; perceived natural skin protection was inversely associated with sunscreen use; skin cancer worry was positively associated with shade seeking and use of sun protective clothing; skin cancer fatalism was negatively associated with shade seeking; and skin color preference was negatively associated with use of sun protective clothing. A number of additional statistically significant associations were identified in bivariate correlation analyses. This study informs the potential content of interventions to promote engagement in sun protection behaviors among U.S. Hispanics.
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Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Hispânico ou Latino/psicologia , Roupa de Proteção/estatística & dados numéricos , Neoplasias Cutâneas/prevenção & controle , Protetores Solares/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/psicologia , Adulto JovemRESUMO
Contrast-enhanced breast MRI has an established role in aiding in the detection, evaluation, and management of breast cancer. This article discusses MRI sequences, the clinical utility of MRI, and how MRI has been evaluated for use in breast radiotherapy treatment planning. We highlight the contribution of MRI in the decision-making regarding selecting appropriate candidates for breast conservation therapy and review the emerging role of MRI-guided breast radiotherapy.
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Purpose: While dose escalation is associated with improved local control (LC) for adrenal gland metastases (AGMs), the proximity of gastrointestinal (GI) organs-at-risk (OARs) limits the dose that can be safely prescribed via CT-based stereotactic body radiation therapy (SBRT). The advantages of magnetic resonance-guided SBRT (MRgSBRT), including tumor tracking and online plan adaptation, facilitate safe dose escalation. Methods: This is a multi-institutional review of 57 consecutive patients who received MRgSBRT on a 0.35-T MR linac to 61 AGMs from 2019 to 2021. The Kaplan-Meier method was used to estimate overall survival (OS), progression-free survival (PFS), and LC, and the Cox proportional hazards model was utilized for univariate analysis (UVA). Results: Median follow up from MRgSBRT was 16.4 months (range [R]: 1.1-39 months). Median age was 67 years (R: 28-84 years). Primary histologies included non-small cell lung cancer (N = 38), renal cell carcinoma (N = 6), and melanoma (N = 5), amongst others. The median maximum diameter was 2.7 cm (R: 0.6-7.6 cm), and most AGMs were left-sided (N = 32). The median dose was 50 Gy (R: 30-60 Gy) in 5-10 fractions with a median BED10 of 100 Gy (R: 48-132 Gy). 45 cases (74 %) required adaptation for at least 1 fraction (median: 4 fractions, R: 0-10). Left-sided AGMs required adaptation in at least 1 fraction more frequently than right-sided AGMs (88 % vs 59 %, p = 0.018). There were 3 cases of reirradiation, including 60 Gy in 10 fractions (N = 1) and 40 Gy in 5 fractions (N = 2). One-year LC, PFS, and OS were 92 %, 52 %, and 78 %, respectively. On UVA, melanoma histology predicted for inferior 1-year LC (80 % vs 93 %, p = 0.012). There were no instances of grade 3+ toxicity. Conclusions: We demonstrate that MRgSBRT achieves favorable early LC and no grade 3 + toxicity despite prescribing a median BED10 of 100 Gy to targets near GI OARs.
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Magnetic resonance imaging (MRI) is known for its accurate soft tissue delineation of tumors and normal tissues. This development has significantly impacted the imaging and treatment of cancers. Radiomics is the process of extracting high-dimensional features from medical images. Several studies have shown that these extracted features may be used to build machine-learning models for the prediction of treatment outcomes of cancer patients. Various feature selection techniques and machine models interrogate the relevant radiomics features for predicting cancer treatment outcomes. This study aims to provide an overview of MRI radiomics features used in predicting clinical treatment outcomes with machine learning techniques. The review includes examples from different disease sites. It will also discuss the impact of magnetic field strength, sample size, and other characteristics on outcome prediction performance.
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Aprendizado de Máquina , Imageamento por Ressonância Magnética , Neoplasias , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/terapia , Imageamento por Ressonância Magnética/métodos , Resultado do Tratamento , Radioterapia Guiada por Imagem/métodos , RadiômicaRESUMO
BACKGROUND: Definitive local therapy with stereotactic ablative radiation therapy (SABR) for ultracentral lung lesions is associated with a high risk of toxicity, including treatment related death. Stereotactic MR-guided adaptive radiation therapy (SMART) can overcome many of the challenges associated with SABR treatment of ultracentral lesions. METHODS: We retrospectively identified 14 consecutive patients who received SMART to ultracentral lung lesions from 10/2019 to 01/2021. Patients had a median distance from the proximal bronchial tree (PBT) of 0.38 cm. Tumors were most often lung primary (64.3%) and HILUS group A (85.7%). A structure-specific rigid registration approach was used for cumulative dose analysis. Kaplan-Meier log-rank analysis was used for clinical outcome data and the Wilcoxon Signed Rank test was used for dosimetric data. RESULTS: Here we show that SMART dosimetric improvements in favor of delivered plans over predicted non-adapted plans for PBT, with improvements in proximal bronchial tree DMax of 5.7 Gy (p = 0.002) and gross tumor 100% prescription coverage of 7.3% (p = 0.002). The mean estimated follow-up is 17.2 months and 2-year local control and local failure free survival rates are 92.9% and 85.7%, respectively. There are no grade ≥ 3 toxicities. CONCLUSIONS: SMART has dosimetric advantages and excellent clinical outcomes for ultracentral lung tumors. Daily plan adaptation reliably improves target coverage while simultaneously reducing doses to the proximal airways. These results further characterize the therapeutic window improvements for SMART. Structure-specific rigid dose accumulation dosimetric analysis provides insights that elucidate the dosimetric advantages of SMART more so than per fractional analysis alone.
Stereotactic MR-guided Adaptive Radiation Therapy (SMART) is a type of radiation therapy for cancer. With SMART, treatment can be adapted based on daily changes in the body seen via imaging. SMART can safely deliver radiation to lung tumors near the center of the body which are risky to treat, due to potential damage to nearby organs. We looked at 14 patients who received SMART to determine how much changing the radiation plan each day improved our ability to safely deliver high doses. We found that SMART not only improved our ability to cover the entirety of the tumor with the dose originally intended, but also reduced dose to nearby organs. Treatment resulted in excellent control of the tumor with few side effects. SMART shows promise for safer and more effective treatment for lung tumors in this part of the body.
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BACKGROUND: Little skin cancer prevention research has focused on the US Hispanic population. OBJECTIVE: This study examined the prevalence and correlates of skin cancer surveillance behaviors among Hispanic adults. METHODS: A population-based sample of 788 Hispanic adults residing in 5 southern and western states completed an online survey in English or Spanish in September 2011. The outcomes were ever having conducted a skin self-examination (SSE) and having received a total cutaneous examination (TCE) from a health professional. The correlates included sociodemographic, skin cancer-related, and psychosocial factors. RESULTS: The rates of ever conducting a SSE or having a TCE were 17.6% and 9.2%, respectively. Based on the results of multivariable logistic regressions, factors associated with ever conducting a SSE included older age, English linguistic acculturation, a greater number of melanoma risk factors, more frequent sunscreen use, sunbathing, job-related sun exposure, higher perceived skin cancer risk, physician recommendation, more SSE benefits, and fewer SSE barriers. Factors associated with ever having a TCE were older age, English linguistic acculturation, a greater number of melanoma risk factors, ever having tanned indoors, greater skin cancer knowledge, higher perceived skin cancer severity, lower skin cancer worry, physician recommendation, more TCE benefits, and fewer SSE barriers. LIMITATIONS: The cross-sectional design limits conclusions regarding the causal nature of observed associations. CONCLUSIONS: Few Hispanic adults engage in skin cancer surveillance behaviors. The study highlights Hispanic subpopulations that are least likely to engage in skin cancer surveillance behaviors and informs the development of culturally appropriate interventions to promote these behaviors.
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Comportamentos Relacionados com a Saúde/etnologia , Neoplasias Cutâneas/prevenção & controle , Adulto , Estudos Transversais , Feminino , Hispânico ou Latino , Humanos , Masculino , Análise Multivariada , Prevalência , Neoplasias Cutâneas/epidemiologia , Estados UnidosRESUMO
Signal transduction mediated by Fas-associated death domain protein (FADD) represents a paradigm of coregulation of apoptosis and cellular proliferation. During apoptotic signaling induced by death receptors including Fas, FADD is required for the recruitment and activation of caspase 8. In addition, a death receptor-independent function of FADD is essential for embryogenesis. In previous studies, FADD deficiency in embryonic stem cells resulted in a complete lack of B cells and dramatically reduced T cell numbers, as shown by Rag1(-/-) blastocyst complementation assays. However, T-specific FADD-deficient mice contained normal numbers of thymocytes and slightly reduced peripheral T cell numbers, whereas B cell-specific deletion of FADD led to increased peripheral B cell numbers. It remains undetermined what impact an FADD deficiency has on hematopoietic stem cells and progenitors. The current study analyzed the effect of simultaneous deletion of FADD in multiple cell types, including bone marrow cells, by using the IFN-inducible Mx1-cre transgene. The resulting FADD mutant mice did not develop lymphoproliferation diseases, unlike Fas-deficient mice. Instead, a time-dependent depletion of peripheral FADD-deficient lymphocytes was observed. In the bone marrow, a lack of FADD led to a dramatic decrease in the hematopoietic stem cells and progenitor-enriched population. Furthermore, FADD-deficient bone marrow cells were defective in their ability to generate lymphoid, myeloid, and erythroid cells. Thus, the results revealed a temporal requirement for FADD. Although dispensable during lymphopoiesis post lineage commitment, FADD plays a critical role in early hematopoietic stages in the bone marrow.
Assuntos
Células da Medula Óssea/imunologia , Células da Medula Óssea/patologia , Proteína de Domínio de Morte Associada a Fas/deficiência , Proteína de Domínio de Morte Associada a Fas/genética , Hematopoese/genética , Hematopoese/imunologia , Depleção Linfocítica/métodos , Animais , Células da Medula Óssea/metabolismo , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Células Cultivadas , Células Precursoras Eritroides/imunologia , Células Precursoras Eritroides/metabolismo , Células Precursoras Eritroides/patologia , Proteínas de Ligação ao GTP/genética , Deleção de Genes , Proteínas de Fluorescência Verde/genética , Integrases/genética , Células Progenitoras Linfoides/imunologia , Células Progenitoras Linfoides/metabolismo , Células Progenitoras Linfoides/patologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Células Progenitoras Mieloides/imunologia , Células Progenitoras Mieloides/metabolismo , Células Progenitoras Mieloides/patologia , Proteínas de Resistência a Myxovirus , Fatores de Tempo , Receptor fas/deficiência , Receptor fas/genéticaRESUMO
The treatment of central and ultracentral lung tumors with radiotherapy remains an ongoing clinical challenge. The risk of Grade 5 toxicity with ablative radiotherapy doses to these high-risk regions is significant as shown in recent prospective studies. Magnetic resonance (MR) image-guided adaptive radiotherapy (MRgART) is a new technology and may allow the delivery of ablative radiotherapy to these high-risk regions safely. MRgART is able to achieve this by utilizing small treatment margins, real-time gating/tracking and on-table plan adaptation to maintain dose to the tumor but limit dose to critical structures. The process of MRgART is complex and has nuances and challenges for the treatment of lung tumors. We outline the critical steps needed for appropriate delivery of MRgART for lung tumors safely and effectively.
RESUMO
PURPOSE: Non-small cell lung cancer (NSCLC) stereotactic body radiation therapy with 50 Gy/5 fractions is sometimes considered controversial, as the nominal biologically effective dose (BED) of 100 Gy is felt by some to be insufficient for long-term local control of some lesions. In this study, we analyzed such patients using explainable deep learning techniques and consequently proposed appropriate treatment planning criteria. These novel criteria could help planners achieve optimized treatment plans for maximal local control. METHODS AND MATERIALS: A total of 535 patients treated with 50 Gy/5 fractions were used to develop a novel deep learning local response model. A multimodality approach, incorporating computed tomography images, 3-dimensional dose distribution, and patient demographics, combined with a discrete-time survival model, was applied to predict time to failure and the probability of local control. Subsequently, an integrated gradient-weighted class activation mapping method was used to identify the most significant dose-volume metrics predictive of local failure and their optimal cut-points. RESULTS: The model was cross-validated, showing an acceptable performance (c-index: 0.72, 95% CI, 0.68-0.75); the testing c-index was 0.69. The model's spatial attention was concentrated mostly in the tumors' periphery (planning target volume [PTV] - internal gross target volume [IGTV]) region. Statistically significant dose-volume metrics in improved local control were BED Dnear-min ≥ 103.8 Gy in IGTV (hazard ratio [HR], 0.31; 95% CI, 015-0.63), V104 ≥ 98% in IGTV (HR, 0.30; 95% CI, 0.15-0.60), gEUD ≥ 103.8 Gy in PTV-IGTV (HR, 0.25; 95% CI, 0.12-0.50), and Dmean ≥ 104.5 Gy in PTV-IGTV (HR, 0.25; 95% CI, 0.12-0.51). CONCLUSIONS: Deep learning-identified dose-volume metrics have shown significant prognostic power (log-rank, P = .003) and could be used as additional actionable criteria for treatment planning in NSCLC stereotactic body radiation therapy patients receiving 50 Gy in 5 fractions. Although our data do not confirm or refute that a significantly higher BED for the prescription dose is necessary for tumor control in NSCLC, it might be clinically effective to escalate the nominal prescribed dose from BED 100 to 105 Gy.