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PURPOSE: Patients living in food priority areas (FPAs), where access to healthy meals is challenging, may be at greater risk of nutritional deficits, leading to poorer cancer outcomes. Currently, there are no published data analyzing how FPAs affect patterns-of-care or outcomes for patients with locally advanced non-small cell lung cancer (NSCLC). We aimed to analyze the effect of residing in an FPA on treatments rendered and cancer outcomes in patients with stage III NSCLC treated at a single institution. METHODS AND MATERIALS: This is a retrospective study of 573 patients with locally advanced NSCLC consecutively treated from January 2000 to January 2020. χ2 and Mann-Whitney U tests were performed to determine differences between select variables. Kaplan-Meier analysis and Cox proportional hazard models were used to analyze overall survival (OS) and freedom from recurrence. Cox regression with forward model selection was used for multivariate analysis. RESULTS: Thirty-two percent of patients resided in an FPA (n = 183) and were more likely to self-identify as Black (P < .0001), single (P < .001), <60 years of age (P = .001), and uninsured (P < .0001), with a lower median income (P < .001). Patients in FPAs also had lower mean pre-chemoradiation (CRT) albumin (P = .002), lower pre-CRT body mass index (BMI) (P = .026), and were less likely to receive trimodality therapy (P ≤ .001) compared with patients not living in FPAs. There was no difference in OS or freedom from recurrence between the 2 cohorts. However, in patients with a normal BMI, either pre-CRT (median OS, 18.4 vs 25.0 months; P = .005) or after CRT (15.1 vs 28.1 months, P = .002), residing in an FPA resulted in an OS detriment. CONCLUSIONS: We demonstrated a clear socioeconomic divide in our patient population with stage III NSCLC, where residing in FPAs was associated with less-aggressive therapy and an OS detriment for patients with a normal-weight BMI. We are currently conducting a prospective study characterizing the nutritional needs of patients, particularly those who live in FPAs.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Índice de Massa Corporal , Estudos Retrospectivos , Estudos Prospectivos , Quimiorradioterapia/métodos , Estadiamento de NeoplasiasRESUMO
With advances in multimodality therapy, childhood cancer cure rates approach 80%. However, both radiotherapy and chemotherapy can cause debilitating or even fatal late adverse events that are critical to understand, mitigate or prevent. QUANTEC (Quantitative Analysis of Normal Tissue Effects in the Clinic) identified radiation dose constraints for normal tissues in adults and pointed out the uncertainties in those constraints. The range of adverse events seen in children is different from that in adults, in part due to the vulnerability/characteristics of radiation damage to developing tissues, and in part due to the typical body sites affected by childhood cancer that lead to collateral irradiation of somewhat different normal tissues and organs compared with adults. Many childhood cancer survivors have a long life expectancy and may develop treatment-induced secondary cancers and severe organ/tissue injury 10, 20 or more years after treatment. Collaborative long-term observational studies and clinical research programmes for survivors of paediatric and adolescent cancer provide adverse event data for follow-up periods exceeding 40 years. Data analysis is challenging due to the interaction between therapeutic and developmental variables, the lack of radiation dose-volume data and the fact that most childhood malignancies are managed with combined modality therapy. PENTEC (Pediatric Normal Tissue Effects in the Clinic) is a volunteer research collaboration of more than 150 physicians, medical physicists, mathematical modellers and epidemiologists organised into 18 organ-specific working groups conducting a critical review and synthesis of quantitative data from existing studies aiming to: (1) establish quantitative, evidence-based dose/volume/risk guidelines to inform radiation treatment planning and, in turn, improve outcomes after radiation therapy for childhood cancers; (2) explore the most relevant risk factors for toxicity, including developmental status; (3) describe specific physics and dosimetric issues relevant to paediatric radiotherapy; and (4) propose dose-volume outcome reporting standards for publications on childhood cancer therapy outcomes. The impact of other critical modifiers of normal tissue radiation damage, including chemotherapy, surgery, stem cell transplantation and underlying genetic predispositions are also considered. The aims of the PENTEC reports are to provide clinicians with an analysis of the best available data to make informed decisions regarding radiation therapy normal organ dose constraints for planning childhood cancer treatment, and to define future research priorities.
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Relação Dose-Resposta à Radiação , Neoplasias/radioterapia , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia/métodos , Adolescente , Adulto , Criança , Humanos , Radioterapia/efeitos adversosRESUMO
BACKGROUND: Diet has an important role in the management of diabetes. However, little is known about dietary intake in Danish diabetes patients. A food frequency questionnaire (FFQ) focusing on most relevant nutrients in diabetes including carbohydrates, dietary fibres and simple sugars was developed and validated. OBJECTIVES: To examine the relative validity of nutrients calculated by a web-based food frequency questionnaire for patients with diabetes. DESIGN: The FFQ was validated against a 4-day pre-coded food diary (FD). Intakes of nutrients were calculated. Means of intake were compared and cross-classifications of individuals according to intake were performed. To assess the agreement between the two methods, Pearson and Spearman's correlation coefficients and weighted kappa coefficients were calculated. SUBJECTS: Ninety patients (64 with type 1 diabetes and 26 with type 2 diabetes) accepted to participate in the study. Twenty-six were excluded from the final study population. SETTING: 64 volunteer diabetes patients at the Steno Diabetes Center. RESULTS: Intakes of carbohydrates, simple sugars, dietary fibres and total energy were higher according to the FFQ compared with the FD. However, intakes of nutrients were grossly classified in the same or adjacent quartiles with an average of 82% of the selected nutrients when comparing the two methods. In general, moderate agreement between the two methods was found. CONCLUSION: The FFQ was validated for assessment of a range of nutrients. Comparing the intakes of selected nutrients (carbohydrates, dietary fibres and simple sugars), patients were classified correctly according to low and high intakes. The FFQ is a reliable dietary assessment tool to use in research and evaluation of patient education for patients with diabetes.
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AIMS: Hypofractionation of postoperative radiotherapy for breast cancer has been evaluated in a number of large randomised clinical trials, but concerns remain over the late cardiac toxicity. In this study, we examined the predictions of the linear quadratic model on the estimated fraction size-corrected dose to the heart for four evidence-based hypofractionation regimens. MATERIALS AND METHODS: Dose plans for 60 left-sided breast cancer patients were analysed. All patients were planned with tangential fields for whole breast irradiation. Dose distributions were corrected to the equivalent dose in 2 Gy fractions (EQD(2)) using the linear quadratic model for five different fractionation schedules (50 Gy/25 fractions and four hypofractionation regimens) and for a range of α/ß values (0-5 Gy). The mean EQD(2) to the heart ( [Formula: see text] ) and the volume receiving 40 Gy ( [Formula: see text] ), both as calculated from the EQD(2) dose distributions, were compared between schedules. RESULTS: For α/ß = 3 Gy, [Formula: see text] favours hypofractionation for 40 Gy/15 fractions, 39 Gy/13 fractions and 42.5 Gy/16 fractions, but not for 41.6 Gy/13 fractions. All of the hypofractionation schedules result in lower [Formula: see text] compared with normofractionation. These results hold as long as α/ß â³ 1.5 Gy. If the heart is blocked from the treatment beam, the fraction size-corrected dose is lower for the first three hypofractionation schedules, compared with normofractionation, even for α/ß = â¼1 Gy. CONCLUSION: For standard tangential field whole breast irradiation, most of the examined hypofractionation schedules are estimated to spare the heart when compared with normofractionation. The dose to the heart, adjusted for fraction size using the linear quadratic model, will generally be lower after hypofractionated compared with normofractionated schedules, even for very low values of α/ß.
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Neoplasias da Mama/radioterapia , Cardiopatias/etiologia , Cardiopatias/prevenção & controle , Coração/efeitos da radiação , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias da Mama/cirurgia , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Coração/anatomia & histologia , Humanos , Modelos Biológicos , Cuidados Pós-Operatórios , Lesões por Radiação/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
PURPOSE: Methods to estimate the likely origin of recurrences after radiation therapy for head and neck squamous cell carcinoma are compared. METHODS AND MATERIALS: A total of 25 patients meeting the following inclusion criteria were randomly selected: curatively intended intensity-modulated radiotherapy planned on a positron emission tomography-computed tomography (PET/CT) scan during the period 2005-2009; squamous cell carcinoma in the oral cavity, pharynx or larynx; complete clinical response followed by locoregional recurrence; and a CT scan at recurrence before any salvage therapy. Exclusion criteria were previous cancer in the area, surgery prior to radiotherapy, or a synchronous cancer. Three methods of estimating focal points of recurrence origin and two volume overlap methods assigning the recurrences to the most central target volumes encompassing at least 50% or 95% of the recurrence volumes were tested. Treatment planning and recurrence scans were rigid and deformable co-registered in order to transfer focal points to the treatment planning scan. Double determinations of all volumes, points, and co-registrations were made. RESULTS: The volume overlap methods assigned the recurrences to significantly more peripheral target volumes than focal methods (p < 0.0001 for all comparisons of 95% overlap vs. focal methods, p < 0.028 for all comparisons of 50% overlap vs. focal methods). Repeated registrations of the same point had higher reproducibility with deformable registration than with rigid registration (median distance 0.31 vs. 0.35 cm, p = 0.015). No significant differences were observed among the focal methods. CONCLUSION: Significant differences between methods were found which may affect strategies to improve radiotherapy based on pattern of failure analyses.
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Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Neoplasias Primárias Desconhecidas/radioterapia , Neoplasias Otorrinolaringológicas/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Quimiorradioterapia , Terapia Combinada , Fracionamento da Dose de Radiação , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Neoplasias Laríngeas/diagnóstico por imagem , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Masculino , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/patologia , Neoplasias Bucais/radioterapia , Neoplasias Bucais/cirurgia , Imagem Multimodal , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Neoplasias Primárias Desconhecidas/diagnóstico por imagem , Neoplasias Primárias Desconhecidas/patologia , Neoplasias Primárias Desconhecidas/cirurgia , Neoplasias Otorrinolaringológicas/diagnóstico por imagem , Neoplasias Otorrinolaringológicas/patologia , Neoplasias Otorrinolaringológicas/cirurgia , Neoplasias Faríngeas/diagnóstico por imagem , Neoplasias Faríngeas/patologia , Neoplasias Faríngeas/radioterapia , Neoplasias Faríngeas/cirurgia , Tomografia por Emissão de Pósitrons , Dosagem Radioterapêutica , Terapia de Salvação , Carcinoma de Células Escamosas de Cabeça e Pescoço , Tomografia Computadorizada por Raios X , Carga TumoralRESUMO
We wanted to illustrate the feasibility of using hyperpolarized helium magnetic resonance imaging (HPH-MRI) to obtain functional information that may assist in improving conformal avoidance of ventilating lung tissue during thoracic radiotherapy. HPH-MRI images were obtained from a volunteer patient and were first fused with a proton density-weighted (PD(w)) MRI to provide corresponding anatomic detail; they were then fused with the treatment planning computed tomography scan of a patient from our treatment planning database who possessed equivalent thoracic dimensions. An optimized treatment plan was then generated using the TomoTherapy treatment planning system, designating the HPH-enhancing regions as ventilation volume (VV). A dose-volume histogram compares the dosimetry of the lungs as a paired organ, the VV, and the lungs minus the VV. The clinical consequences of these changes was estimated using a bio-effect model, the parallel architecture model, or the local damage (f(dam)) model. Model parameters were chosen from published studies linking the incidence of grade 3+ pneumonitis, with the dose and volume irradiated. For two hypothetical treatment plans of 60 Gy in 30 fractions delivered to a right upper-lobe lung mass, one using and one ignoring the VV as an avoidance structure, the mean normalized total dose (NTD(mean)) values for the lung subvolumes were: lungs = 12.5 Gy3 vs. 13.52 Gy3, VV = 9.94 Gy3 vs. 13.95 Gy3, and lungs minus VV = 16.69 Gy3 vs. 19.16 Gy3. Using the f(dam) values generated from these plans, one would predict a reduction of the incidence of grade 3+ radiation pneumonitis from 12%-4% when compared with a conventionally optimized plan. The use of HPH-MRI to identify ventilated lung subvolumes is feasible and has the potential to be incorporated into conformal avoidance treatment planning paradigms. A prospective clinical study evaluating this imaging technique is being developed.
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Hélio , Lesão Pulmonar/prevenção & controle , Pulmão/patologia , Imageamento por Ressonância Magnética/métodos , Troca Gasosa Pulmonar , Lesões por Radiação/prevenção & controle , Radioterapia Conformacional/métodos , Humanos , Isótopos , Lesão Pulmonar/etiologia , Lesões por Radiação/etiologia , Proteção Radiológica , Compostos Radiofarmacêuticos , Radioterapia Conformacional/efeitos adversos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: Phase II studies in laryngeal and bladder carcinoma of accelerated radiotherapy with carbogen and nicotinamide (RT+CON) suggested a therapeutic advantage. Therefore, a randomized phase-III trial of RT+CON in locally advanced bladder carcinoma compared to radiotherapy (RT) alone was undertaken. METHODS: One hundred and sixty-five patients with muscle-invasive transitional cell bladder carcinoma were randomized to RT alone and 168 to RT+CON. This paper reports on compliance and toxicity to nicotinamide (NAM) and carbogen and on early radiation-induced adverse bowel and urinary events. RESULTS: Of those receiving RT+CON, 65-69% accepted all doses of NAM. Sixty-four percent of patients presented Grade 1 NAM toxicity (nausea or vomiting), which was severe in 13%. Compliance to carbogen was 85% and none (32 fractions) and 2% (20 fractions) of patients presented severe toxicity. The highest prevalence of severe radiation acute morbidity was seen for urinary frequency (RT: 18% and RT+CON: 15%) and for diarrhea (RT: 3% and RT+CON: 5%). CONCLUSIONS: There is no indication of an increase in radiation-induced morbidity by combining the tumour radiosensitizers carbogen and nicotinamide with radiotherapy. Late morbidity and treatment outcome will ultimately determine if there is a therapeutic benefit.
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Dióxido de Carbono/uso terapêutico , Carcinoma de Células de Transição/radioterapia , Niacinamida/uso terapêutico , Oxigênio/uso terapêutico , Radiossensibilizantes/uso terapêutico , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Idoso de 80 Anos ou mais , Dióxido de Carbono/efeitos adversos , Carcinoma de Células de Transição/patologia , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Niacinamida/efeitos adversos , Oxigênio/efeitos adversos , Radiossensibilizantes/efeitos adversos , Dosagem Radioterapêutica , Resultado do Tratamento , Neoplasias da Bexiga Urinária/patologiaRESUMO
To improve local control for inoperable non-small cell lung cancer (NSCLC), a phase I dose escalation study for locally advanced and medically inoperable patients was devised to escalate tumor dose while limiting the dose to organs at risk including the esophagus, spinal cord, and residual lung. Helical tomotherapy provided image-guided IMRT, delivered in a 5-week hypofractionated schedule to minimize the effect of accelerated repopulation. Forty-six patients judged not to be surgical candidates with Stage I-IV NSCLC were treated. Concurrent chemotherapy was not allowed. Radiotherapy was delivered via helical tomotherapy and limited to the primary site and clinically proven or suspicious nodal regions without elective nodal irradiation. Patients were placed in 1 of 5 dose bins, all treated for 25 fractions, with dose per fraction ranging from 2.28 to 3.22 Gy. The bin doses of 57 to 80.5 Gy result in 2 Gy/fraction normalized tissue dose (NTD) equivalents of 60 to 100 Gy. In each bin, the starting dose was determined by the relative normalized tissue mean dose modeled to cause < 20% Grade 2 pneumonitis. Dose constraints included spinal cord maximum NTD of 50 Gy, esophageal maximum NTD < 64 Gy to < or = 0.5 cc volume, and esophageal effective volume of 30%. No grade 3 RTOG acute pneumonitis (NCI-CTC v.3) or esophageal toxicities (CTCAE v.3.0 and RTOG) were observed at median follow-up of 8.1 months. Pneumonitis rates were 70% grade 1 and 13% grade 2. Multivariate analysis identified lung NTD(mean) (p=0.012) and administration of adjuvant chemotherapy following radiotherapy (p=0.015) to be independent risk factors for grade 2 pneumonitis. Only seven patients (15%) required narcotic analgesics (RTOG grade 2 toxicity) for esophagitis, with only 2.3% average weight loss during treatment. Best in-field gross response rates were 17% complete response, 43% partial response, 26% stable disease, and 6.5% in-field thoracic progression. The out-of-field thoracic failure rate was 13%, and distal failure rate was 28%. The median survival was 18 months with 2-year overall survival of 46.8% +/- 9.7% for this cohort, 50% of whom were stage IIIB and 30% stage IIIA. Dose escalation can be safely achieved in NSCLC with lower than expected rates of pneumonitis and esophagitis using hypofractionated image-guided IMRT. The maximum tolerated dose has yet to be reached.
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Carcinoma Pulmonar de Células não Pequenas/radioterapia , Fracionamento da Dose de Radiação , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: The international standard radiotherapy schedule for breast cancer treatment delivers a high total dose in 25 small daily doses (fractions). However, a lower total dose delivered in fewer, larger fractions (hypofractionation) is hypothesised to be at least as safe and effective as the standard treatment. We tested two dose levels of a 13-fraction schedule against the standard regimen with the aim of measuring the sensitivity of normal and malignant tissues to fraction size. METHODS: Between 1998 and 2002, 2236 women with early breast cancer (pT1-3a pN0-1 M0) at 17 centres in the UK were randomly assigned after primary surgery to receive 50 Gy in 25 fractions of 2.0 Gy versus 41.6 Gy or 39 Gy in 13 fractions of 3.2 Gy or 3.0 Gy over 5 weeks. Women were eligible if they were aged over 18 years, did not have an immediate surgical reconstruction, and were available for follow-up. Randomisation method was computer generated and was not blinded. The protocol-specified principal endpoints were local-regional tumour relapse, defined as reappearance of cancer at irradiated sites, late normal tissue effects, and quality of life. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. FINDINGS: 749 women were assigned to the 50 Gy group, 750 to the 41.6 Gy group, and 737 to the 39 Gy group. After a median follow up of 5.1 years (IQR 4.4-6.0) the rate of local-regional tumour relapse at 5 years was 3.6% (95% CI 2.2-5.1) after 50 Gy, 3.5% (95% CI 2.1-4.3) after 41.6 Gy, and 5.2% (95% CI 3.5-6.9) after 39 Gy. The estimated absolute differences in 5-year local-regional relapse rates compared with 50 Gy were 0.2% (95% CI -1.3% to 2.6%) after 41.6 Gy and 0.9% (95% CI -0.8% to 3.7%) after 39 Gy. Photographic and patient self-assessments suggested lower rates of late adverse effects after 39 Gy than with 50 Gy, with an HR for late change in breast appearance (photographic) of 0.69 (95% CI 0.52-0.91, p=0.01). From a planned meta-analysis with the pilot trial, the adjusted estimates of alpha/beta value for tumour control was 4.6 Gy (95% CI 1.1-8.1) and for late change in breast appearance (photographic) was 3.4 Gy (95% CI 2.3-4.5). INTERPRETATION: The data are consistent with the hypothesis that breast cancer and the dose-limiting normal tissues respond similarly to change in radiotherapy fraction size. 41.6 Gy in 13 fractions was similar to the control regimen of 50 Gy in 25 fractions in terms of local-regional tumour control and late normal tissue effects, a result consistent with the result of START Trial B. A lower total dose in a smaller number of fractions could offer similar rates of tumour control and normal tissue damage as the international standard fractionation schedule of 50 Gy in 25 fractions.
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Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Fracionamento da Dose de Radiação , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Intervalos de Confiança , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Mastectomia Segmentar/métodos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Modelos de Riscos Proporcionais , Dosagem Radioterapêutica/normas , Radioterapia Adjuvante , Valores de Referência , Medição de Risco , Fatores Sexuais , Análise de Sobrevida , Resultado do Tratamento , Reino UnidoRESUMO
BACKGROUND: The international standard radiotherapy schedule for early breast cancer delivers 50 Gy in 25 fractions of 2.0 Gy over 5 weeks, but there is a long history of non-standard regimens delivering a lower total dose using fewer, larger fractions (hypofractionation). We aimed to test the benefits of radiotherapy schedules using fraction sizes larger than 2.0 Gy in terms of local-regional tumour control, normal tissue responses, quality of life, and economic consequences in women prescribed post-operative radiotherapy. METHODS: Between 1999 and 2001, 2215 women with early breast cancer (pT1-3a pN0-1 M0) at 23 centres in the UK were randomly assigned after primary surgery to receive 50 Gy in 25 fractions of 2.0 Gy over 5 weeks or 40 Gy in 15 fractions of 2.67 Gy over 3 weeks. Women were eligible for the trial if they were aged over 18 years, did not have an immediate reconstruction, and were available for follow-up. Randomisation method was computer generated and was not blinded. The protocol-specified principal endpoints were local-regional tumour relapse, defined as reappearance of cancer at irradiated sites, late normal tissue effects, and quality of life. Analysis was by intention to treat. This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN59368779. FINDINGS: 1105 women were assigned to the 50 Gy group and 1110 to the 40 Gy group. After a median follow up of 6.0 years (IQR 5.0-6.2) the rate of local-regional tumour relapse at 5 years was 2.2% (95% CI 1.3-3.1) in the 40 Gy group and 3.3% (95% CI 2.2 to 4.5) in the 50 Gy group, representing an absolute difference of -0.7% (95% CI -1.7% to 0.9%)--ie, the absolute difference in local-regional relapse could be up to 1.7% better and at most 1% worse after 40 Gy than after 50 Gy. Photographic and patient self-assessments indicated lower rates of late adverse effects after 40 Gy than after 50 Gy. INTERPRETATION: A radiation schedule delivering 40 Gy in 15 fractions seems to offer rates of local-regional tumour relapse and late adverse effects at least as favourable as the standard schedule of 50 Gy in 25 fractions.
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Neoplasias da Mama/radioterapia , Radioterapia de Alta Energia/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/cirurgia , Fracionamento da Dose de Radiação , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Modelos de Riscos Proporcionais , Qualidade de Vida , Dosagem Radioterapêutica , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Reino UnidoRESUMO
We have used DNA microarrays to identify changes in gene expression in cells of the radioresistant human glioma cell lines T98G and U373 after low radiation doses (0.2-2 Gy). Using Bayesian linear models, we have identified a set of genes that respond to low doses of radiation; furthermore, a hypothesis-driven approach to data analysis has allowed us to identify groups of genes with defined non-linear dose responses. Specifically, one of the cell lines we have examined (T98G) shows increased radiosensitivity at low doses (low-dose hyper-radiosensitivity, HRS); thus we have also assessed sets of genes whose dose response mirrors this survival pattern. We have also investigated a time course for induction of genes over the period when the DNA damage response is expected to occur. We have validated these data using quantitative PCR and also compared genes up-regulated in array data to genes present in the polysomal RNA fraction after irradiation. Several of the radioresponsive genes that we describe code for proteins that may have an impact on the outcome of irradiation in these cells, including RAS homologues and kinases involved in checkpoint signaling, so understanding their differential regulation may suggest new ways of altering radioresistance. From a clinical perspective these data may also suggest novel targets that are specifically up-regulated in gliomas during radiotherapy treatments.
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Expressão Gênica/efeitos da radiação , Glioma/radioterapia , Linhagem Celular Tumoral , Relação Dose-Resposta à Radiação , Glioma/metabolismo , Humanos , Reação em Cadeia da Polimerase , Tolerância a Radiação , Fatores de TempoRESUMO
BACKGROUND: Acute dysphagia is a distressing dose-limiting toxicity after concurrent chemoradiation or high-dose radiotherapy for lung cancer. We therefore identified factors associated with the occurrence of acute dysphagia in lung cancer patients receiving radiotherapy alone or combined with chemotherapy. PATIENTS AND METHODS: Radiotherapy, chemotherapy and patient characteristics were analyzed using ordinal regression analysis as possible predictors for acute dysphagia (CTCAE 3.0) in 328 lung cancer patients treated with curative intent. RESULTS: The most significant association was seen between the maximal grade of neutropenia during chemoradiation and dysphagia, with an odds ratio increasing from 1.49 [95% confidence interval (CI) 0.63-3.54, P = 0.362] for grade 1-2 neutropenia to 19.7 (95% CI 4.66-83.52, P < 0.001) for patients with grade 4 neutropenia. Twice-daily schedule, mean esophageal dose and administration of chemotherapy were significant predictive factors. By combining these factors, a high-performance predictive model was made. On an individual patient level, 64% of patients were correctly classified and only 1.2% of patients were misclassified by more than one grade. CONCLUSIONS: The maximal neutrophil toxicity during concurrent chemotherapy and radiotherapy is strongly associated with the development of acute dysphagia. A multivariate predictive model was developed.
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Transtornos de Deglutição/etiologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neutropenia/etiologia , Lesões por Radiação/etiologia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/radioterapia , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos RetrospectivosRESUMO
PURPOSE: To determine whether tumour radiosensitization and the therapeutic benefit of administering carbogen with nicotinamide depend upon irradiating at the time of peak drug concentration. MATERIALS AND METHODS: Local tumour control of CaNT tumours in CBA mice and acute skin reactions in albino WHT mice were assessed after treatment with 10 X-ray fractions in air, carbogen alone or combined with 0.1, 0.2 or 0.5 mg g(-1) nicotinamide, injected 15, 30 or 60 min before irradiation. Plasma and tumour drug pharmacokinetics were performed. RESULTS: Nicotinamide was rapidly taken up into tumours; a six- and threefold higher concentration was obtained with 0.5 mg g(-1) compared with 0.1 and 0.2 mg g(-1), respectively. Tumour, but not skin, radiosensitization increased as the dose of nicotinamide increased (p = 0.03), but at each dose level there was no significant difference in radiosensitivity when irradiations were done at or after the time of peak concentration. An almost eightfold increase in plasma levels increased tumour enhancement ratios from 1.74 to 1.92 (p < 0.0001). In tumours all schedules gave significant enhancement relative to carbogen alone (p < or = 0.04). CONCLUSIONS: Tumour and skin radiosensitivity was independent of time of nicotinamide administration. Higher drug concentrations were not mirrored by proportionally higher enhancement ratios. Lower plasma levels than previously suggested significantly enhanced tumour radiosensitivity relative to carbogen alone. The clinical implications of these findings are discussed.
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Dióxido de Carbono/farmacologia , Neoplasias Mamárias Experimentais/radioterapia , Niacinamida/farmacologia , Oxigênio/farmacologia , Radiossensibilizantes/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Camundongos , Camundongos Endogâmicos CBA , Niacinamida/farmacocinética , Pele/efeitos da radiaçãoRESUMO
Serum haemoglobin has been shown to be an independent prognostic factor for a number of cancers including head and neck, bladder, cervix and anal cancers. This study has investigated the prognostic significance of pre-treatment haemoglobin in 164 consecutive patients receiving radical radiotherapy for non-small cell lung cancer. Forty-six received conventional fractionation to 60 Gy in 30 fractions and the remainder received accelerated fractionation, either CHART, 54 Gy in 36 fractions over 12 days (27 patients) or CHARTWEL, 60 Gy in 40 fractions over 18 days (76 patients). Patients were divided into three equal groups by haemoglobin concentration. The median overall survival in each of the three groups from lowest to highest haemoglobin was 17.5 months (95% CI 7.9 25), 18.4 months (95% CI 15.0 25.9) and 16.3 months (95% CI 13.0-19.6). No significant effect of pre-treatment haemoglobin concentration was seen in predicting overall, local disease free or metastases free survival.
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Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Hemoglobinas , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Valor Preditivo dos Testes , Prognóstico , Estudos RetrospectivosRESUMO
Cellular repopulation is one of the most important biological determinants of the clinical outcome of fractionated radiation therapy. A number of randomized controlled trials of altered dose-fractionation have been conducted in patients with squamous cell carcinoma of the head and neck (HNSCC) and the main biological lessons from these are summarised. Data for other tumour histologies are relatively sparse. Further progress in radiotherapy for HNSCC is unlikely to result from altered fractionation alone, but a number of novel strategies for overcoming or exploiting repopulation are being researched. In the next 5 years, the top priorities for clinical and translational research in this field should be the development of clinically applicable predictive assays, functional imaging as an aid to optimize the dose distribution, optimization of combined modality therapies and novel biological strategies specifically targeting tumour cell proliferation.
Assuntos
Neoplasias/radioterapia , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Divisão Celular/efeitos da radiação , Terapia Combinada , Fracionamento da Dose de Radiação , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Neoplasias/patologiaRESUMO
Squamous cell carcinoma of the head and neck (HNSCC) are increasingly treated by multimodality approaches combining surgery, radiotherapy and chemotherapy. Randomised controlled trials have demonstrated major improvements in loco-regional tumour control from altered fractionation radiotherapy, accelerated fractionation and hyperfractionation, as compared with conventional fractionation. This experience is summarised, and the limit as to how far these modifications can be taken is discussed. It is emphasised that radiation fractionation will need to be optimised separately in multimodality strategies. Combined chemotherapy and radiotherapy has also been shown in phase III trials to produce an improved survival and an improved disease control. Chemotherapy may be given as neoadjuvant, concurrent or adjuvant treatment and the biological rationales for each of these, and the data supporting them, are reviewed. Although, large meta-analyses have shown concurrent chemoradiation to be the most effective, there is still a strong rationale for trying to develop neoadjuvant and adjuvant schedules. New, more active drugs may be important in this context. As therapy is becoming more intense, a careful recording and reporting of treatment-related morbidity is a crucial element in estimating the therapeutic gain from competing therapeutic management strategies. Development of non-cytostatic drugs and individualization of therapy using molecular prognostic markers are exciting areas of research with a great potential for improving therapy in the next decade and these are briefly discussed. Finally, a number of avenues for further research are identified.
Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Ensaios Clínicos Fase III como Assunto , Terapia Combinada , Fracionamento da Dose de Radiação , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND AND PURPOSE: Evidence-based medicine requires the systematic and critical evaluation of published and unpublished trials. Problems arise when a clinical condition is relatively rare and the only available data relate to experiential knowledge. The way forward would be to recommend the development of good quality randomized controlled studies. Until then, we are left with the situation where some information exists, albeit in the form of case reports and small series. Should this information be used and what features would determine its strength? METHODS: Using the example of formalin therapy in haemorrhagic radiation proctitis, a treatment for a rare condition, we were able to identify 16 published studies, 13 of which were retrospective and three of which were prospective. The quality of reporting detail was assessed by comparison to the features in a 'proposed minimum dataset' for an uncontrolled study addressing this topic. RESULTS: The mean score for quality of reporting detail for these studies was 50.6% (range 25-70%). Earlier studies reported a significantly higher response rate than subsequent studies and although there was a tendency for smaller studies to report higher response rates, this was not significant. The score for detail of reporting did not improve with year of publication and the correlation between the size of the study and the detail of reporting was not statistically significant. CONCLUSIONS: The information presented is of exceedingly variable quality. If these studies are to be used, where insufficient controlled trials are available, they should be scored for methodology, and these scores used to assist interpretation of results. This would be facilitated if an accepted reporting format including specific criteria was available.
Assuntos
Formaldeído/uso terapêutico , Proctite/tratamento farmacológico , Viés de Publicação , Lesões por Radiação/tratamento farmacológico , Estudos de Avaliação como Assunto , Medicina Baseada em Evidências , Humanos , Morbidade , Variações Dependentes do Observador , Publicações Periódicas como Assunto , Estudos Prospectivos , Editoração , Projetos de Pesquisa , Estudos RetrospectivosRESUMO
Data are now available from a U.K. audit of survival and late morbidity following curative radiotherapy for cancer of the cervix treated in 1993. The complication rate per centre ranges from 0 to 67%. Although the frequency of complications following curative radiotherapy for cancer of the cervix might be considered to be an indicator of clinical performance, variation in treatment outcomes can be explained by sampling variability rather than real differences in quality of care. In the present study we have asked the question: could the disparity in complication rates between centres be no more or less than would be expected by chance? Our analysis suggests that this is the case, and for this reason it would be premature to use such outcome data to produce league tables or to assess institutional differences. Thus, ranking centres according to complication rate would not be valid, as the differences in rates observed are probably not significantly different from the national average. It is important that audit data are not used inappropriately and this analysis further highlights the need for reliable prospective collection of clinical information and the importance of considering sampling variability in interpreting the results of such studies.