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1.
Environ Sci Pollut Res Int ; 30(15): 43387-43402, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36656477

RESUMEN

In this study, simulations were performed to investigate the influence of different vehicle climate ventilation strategies, mainly the air recirculation (REC) degree, on the cabin air quality and climate system power. The focus of air quality is on the cabin particle concentrations including PM2.5 (particles of aerodynamic diameter less than 2.5 µm), UFP (ultrafine particles of aerodynamic diameter less than 100 nm), and cabin CO2 concentration. Three outside climates (cold, intermediate, and warm) and three outside particle concentrations are studied. The studied vehicle originally shows possibilities to meet WHO PM2.5 guideline of 15 µg/m3 with a new filter. The aged filter have reduced performance, especially when outside concentration is high. Increased REC shows advantages in all the three climates in reducing particles and climate power for the studied vehicle. Application of 70% REC (70% of ventilation air is recirculated air) on average lowers PM2.5 by 55% and 39% for a new and aged filter, respectively. 70% REC with a new filter reduces cabin PM2.5 below guideline of 15 µg/m3 in all conditions. The reduction of UFP counts results are generally similar to that of PM2.5. Increased REC also lessens the average climate system power by up to 27% on average. When REC is increased, the cabin CO2 concentration arises accordingly, and the magnitude is relevant to the passengers. In all studied conditions with 1 passenger, 70% REC does not increase CO2 above the common guideline of 1000 ppm. 70% REC is not recommended with more than 1 passengers in cold and intermediate climate and 2 passengers in warm climate. Besides, to avoid the potential windscreen fog risk in cold climate, REC should be avoided when passengers are more than 3. Except for constant REC values, a sample study investigates a dynamic control of the REC. It shows the possibility of continuously optimizing REC to reduce the climate power and particles, while maintaining the CO2 concentration below 1000 ppm. In warm climate with 1 passenger boarded, the average optimized REC is 90%, which in comparison with base case lead to 44% PM2.5 reduction and 12% climate power reduction.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Tamaño de la Partícula , Contaminación del Aire/análisis , Material Particulado/análisis , Contaminación del Aire Interior/análisis , Monitoreo del Ambiente/métodos
2.
Environ Sci Pollut Res Int ; 29(30): 45364-45379, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35146602

RESUMEN

The main aim of this study is to develop a mathematical size-dependent vehicle cabin model for particulate matter concentration including PM2.5 (particles of aerodynamic diameter less than 2.5 µm) and UFPs (ultrafine particles of aerodynamic diameter less than 100 nm), as well as CO2 concentration. The ventilation airflow rate and cabin volume parameters are defined from a previously developed vehicle model for climate system design. The model simulates different filter statuses, application of pre-ionization, different airflow rates and recirculation degrees. Both particle mass and count concentration within 10-2530 nm are simulated. Parameters in the model are defined from either available component test data (for example filter efficiencies) or assumptions from corresponding studies (for example particle infiltration and deposition rates). To validate the model, road measurements of particle and CO2 concentrations outside two vehicles were used as model inputs. The simulated inside PM2.5, UFP and CO2 concentration were compared with the inside measurements. Generally, the simulation agrees well with measured data (Person's r 0.89-0.92), and the simulation of aged filter with ionization is showing higher deviation than others. The simulation using medium airflows agrees better than the simulation using other airflows, both lower and higher. The reason for this may be that the filter efficiency data used in the model were obtained at airflows close to the medium airflow. When all size bins are compared, the sizes of 100-300 nm were slightly overestimated. The results indicated that among others, expanded filter efficiency data as a function of filter ageing and airflow rate would possibly enhance the simulation accuracy. An initial application sample study on recirculation degrees presents the model's possible application in developing advanced climate control strategies.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Anciano , Contaminantes Atmosféricos/análisis , Dióxido de Carbono , Monitoreo del Ambiente/métodos , Humanos , Tamaño de la Partícula , Material Particulado/análisis , Emisiones de Vehículos/análisis
3.
Environ Sci Pollut Res Int ; 27(24): 30815-30830, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32474777

RESUMEN

The main aim of the study was to evaluate the influence of filter status (new and aged), pre-ionization, on the particle filtration in modern passenger cars. Measurements of in-cabin and outside PM2.5 (dp < 2.5 µm) concentration and UFP (ultrafine particle, dp < 100 nm) counts, to calculate I/O (indoor to outdoor) ratios, were performed. They were done at two locations, to study the influence of different outside conditions on the HVAC (heating, ventilation, and air-conditioning) system. The measurements were performed in two new cars, with similar HVAC systems and settings, using a new filter and an aged synthetic filter. Furthermore, an ionization unit was installed upstream of the filter in both cars. This enabled the study of filter status, with and without ionization, under common driving conditions. The results show that the HVAC system performances were very similar at the two locations, with average I/O ratios of 0.35-0.40 without ionization and 0.15-0.20 with ionization applied, although the outside conditions were considerably different. Furthermore, the aged filter clearly worsened the filtration ability. Considering the corresponding average PM2.5 I/O ratios in one location as an example, the average for the new filter was 0.20 and 0.60 for the aged filter. The corresponding UFP I/O ratios were 0.24 and 0.57. Other findings are that the aged filter with ionization reached a performance close to the new filter (without ionization), and that increased ventilation airflow and decreased recirculation degree, as expected, led to an increase in the I/O ratio for both particle sizes.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Automóviles , China , Monitoreo del Ambiente , Tamaño de la Partícula , Material Particulado/análisis , Suecia , Ventilación
4.
Indoor Air ; 29(6): 913-925, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31420890

RESUMEN

This study aimed to better understand and quantify the influence of ventilation strategies on occupant-related indoor air chemistry. The oxidation of human skin oil constituents was studied in a continuously ventilated climate chamber at two air exchange rates (1 h-1 and 3 h-1 ) and two initial ozone mixing ratios (30 and 60 ppb). Additional measurements were performed to investigate the effect of intermittent ventilation ("off" followed by "on"). Soiled t-shirts were used to simulate the presence of occupants. A time-of-flight-chemical ionization mass spectrometer (ToF-CIMS) in positive mode using protonated water clusters was used to measure the oxygenated reaction products geranyl acetone, 6-methyl-5-hepten-2-one (6-MHO) and 4-oxopentanal (4-OPA). The measurement data were used in a series of mass balance models accounting for formation and removal processes. Reactions of ozone with squalene occurring on the surface of the t-shirts are mass transport limited; ventilation rate has only a small effect on this surface chemistry. Ozone-squalene reactions on the t-shirts produced gas-phase geranyl acetone, which was subsequently removed almost equally by ventilation and further reaction with ozone. About 70% of gas-phase 6-MHO was produced in surface reactions on the t-shirts, the remainder in secondary gas-phase reactions of ozone with geranyl acetone. 6-MHO was primarily removed by ventilation, while further reaction with ozone was responsible for about a third of its removal. 4-OPA was formed primarily on the surfaces of the shirts (~60%); gas-phase reactions of ozone with geranyl acetone and 6-MHO accounted for ~30% and ~10%, respectively. 4-OPA was removed entirely by ventilation. The results from the intermittent ventilation scenarios showed delayed formation of the reaction products and lower product concentrations compared to continuous ventilation.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Ozono/análisis , Piel/química , Ventilación/métodos , Aldehídos/análisis , Entorno Construido , Vestuario , Monitoreo del Ambiente/métodos , Humanos , Cetonas/análisis , Espectrometría de Masas/métodos , Oxidación-Reducción , Terpenos/análisis
5.
Radiother Oncol ; 118(2): 335-41, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26777124

RESUMEN

BACKGROUND AND PURPOSE: Health related quality of life (HRQoL) was assessed in the randomised, prospective ARTSCAN study comparing conventional radiotherapy (CF) with accelerated radiotherapy (AF) for head and neck cancer. MATERIAL AND METHODS: 750 patients with squamous cell carcinoma (of any grade and stage) in the oral cavity, oro-, or hypopharynx or larynx (except T1-2, N0 glottic carcinoma) without distant metastases were randomised to either conventional fractionation (2 Gy/day, 5 days/week in 49 days, total dose 68 Gy) or accelerated fractionation (1.1+2.0 Gy/day, 5 days/week in 35 days, total dose 68 Gy). HRQoL was assessed with EORTC QLQ-C30, QLQ-H&N35 and HADS at baseline, at end of radiotherapy (eRT) and at 3 and 6 months and 1, 2 and 5 years after start of treatment. RESULTS: The AF group reported HRQoL was significantly lower at eRT and at 3 months for most symptoms, scales and functions. Few significant differences were noted between the groups at 6 months and 5 years. Scores related to functional oral intake never reached baseline. CONCLUSION: In comparison to CF, AF has a stronger adverse effect on HRQoL in the acute phase.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Calidad de Vida , Adulto , Anciano , Anciano de 80 o más Años , Fraccionamiento de la Dosis de Radiación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
6.
Radiother Oncol ; 117(1): 99-105, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26427805

RESUMEN

BACKGROUND AND PURPOSE: This report contains the mature five-year data from the Swedish ARTSCAN trial including information on the influence of p16 positivity (p16+) for oropharyngeal cancers. MATERIAL AND METHODS: Patients with previously untreated squamous cell carcinoma without distant metastases of the oral cavity, oropharynx, larynx (except T1-2, N0 glottic cancers) and hypopharynx were included. Patients were randomised between accelerated fractionation (AF) (1.1Gy+2Gy per day, 5days/week for 4.5weeks, total dose 68Gy) and conventional fractionation (CF) (2Gy per day, 5days/week for 7weeks, total dose 68Gy). Human papillomavirus (HPV)-associated p16-expression was assessed retrospectively in tumour tissues from patients with oropharyngeal carcinoma. RESULTS: There was no significant difference in loco-regional control (LRC) between AF and CF (log-rank test p=0.75). LRC at 5years was 65.5% for AF and 64.9% for CF. Overall survival (OS) was similar in both arms (p=0.99). The estimated cancer specific survival (CSS) at 5years was 62.2% (AF) and 63.3% (CF) (p=0.99). 206 specimens were analysed for p16 with 153 specimens (74%) identified as p16+. P16 status did not discriminate for response to AF vs. CF with regard to LRC, OS or CSS. Patients with p16+ tumours had a statistically significant better overall prognosis compared with p16- tumours. CONCLUSION: This update confirms the results of the 2-year report. We failed to identify a positive effect resulting from AF with regards to LRC, OS and CSS. The addition of information on the HPV-associated p16 overexpression did not explain this lack of effect.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Fraccionamiento de la Dosis de Radiación , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/virología , Papillomavirus Humano 16/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/virología , Infecciones por Papillomavirus/complicaciones , Pronóstico , Estudios Retrospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello
7.
Environ Sci Technol ; 49(11): 6891-8, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-25923591

RESUMEN

Previous research has demonstrated that unipolar ionization can enhance the filter performance to collect airborne particles, aeroallergens, and airborne microorganisms, without affecting the filter pressure drop. However, there is a lack of research on the long-term system performance as well as the influence of environmental and operational parameters. In this paper, both field and laboratory tests were carried out to evaluate the long-term particle collection efficiency of a synthetic filter of class M6 with and without ionization. The effect of air velocity, temperature, relative humidity, and particle concentration were further investigated in laboratory tests. Results showed that ionization enhanced the filtration efficiency by 40%-units during most of the operation time. When the ionization system was managed by periodically switching the ionizer polarity, the filtration efficiency against PM0.3-0.5 was maintained above 50% during half a year. Furthermore, the pressure drop of the ionizer-assisted M6 filter was 25-30% lower than that of a filter of class F7. The evaluation of various influencing factors demonstrated that (1) air moisture reduced the increase of filtration efficiency; (2) higher upstream particle concentration and air velocity decreased the filtration efficiency; and (3) the air temperature had very limited effect on the filtration efficiency.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Filtración/métodos , Tamaño de la Partícula , Humedad , Ozono/análisis , Presión , Temperatura , Factores de Tiempo
8.
Med Oncol ; 30(1): 320, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23254960

RESUMEN

The prognosis for patients with lung cancer is poor with an average of 5-year overall survival rate of only 10-15 % taking all clinical stages together. The aim of this study was to elucidate the impact of the radiotherapy regimen on survival. Clinical data were collected from all the Swedish Oncology Departments for 1,287 patients with a diagnosed non-small cell lung cancer (NSCLC) subjected to curatively intended irradiation (≥50 Gy) during the years 1990 to 2000. The included patients were identified based on a manual search of all medical and radiation charts at the oncology departments from which the individual patient data were collected. Patients who did not have a histopathological diagnosis date and/or death date/last follow-up date as well as patients being surgically treated were excluded from the study (n = 592). Thus, 695 patients were included in the present study. Patients who received hyperfractionated radiotherapy (HR) had a higher local control rate compared with patients receiving conventional fractionation (CF) (38 vs. 49 % local relapse). The difference in survival between the two radiotherapy regimens was statistically significant in a univariate Cox analysis (p = 0.023) in favor of HR. This significance was, however, not retained in a multivariate Cox analysis (p = 0.56). Thus, the possible beneficial effects of hyperfractionation are still unclear and need to be further investigated in well-controlled prospective clinical trials, preferably including systemic treatment with novel drugs.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Fraccionamiento de la Dosis de Radiación , Neoplasias Pulmonares/radioterapia , Anciano , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales
9.
Acta Oncol ; 51(6): 759-67, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22793039

RESUMEN

INTRODUCTION: The aim of the present study was to investigate the impact of age at diagnosis on prognosis in patients treated with curatively intended radiotherapy for NSCLC. MATERIAL AND METHODS: This is a joint effort among all the Swedish Oncology Departments that includes all identified patients with a diagnosed non-small cell lung cancer that have been subjected to curatively intended irradiation (≥50 Gy) treated during 1990 to 2000. Included patients had a histopathological/cytological diagnosis date as well as a death date or a last follow-up date. The following variables were studied in relation to overall and disease-specific survival: age, gender, histopathology, time period, smoking status, stage and treatment. RESULTS: The median overall survival of all 1146 included patients was 14.7 months, while the five-year overall survival rate was 9.5%. Younger patients (<55 years), presented with a more advanced clinical stage but had yet a significantly better overall survival compared with patients in the age groups 55-64 years (p = 0.035) and 65-74 years (p = 0.0097) in a multivariate Cox regression analysis. The overall survival of patients aged ≥75 years was comparable to those aged <55 years. CONCLUSION: In this large retrospective study we describe that patients younger than 55 years treated with curatively intended radiotherapy for NSCLC have a better overall survival than patients aged 55-64 and 65-74 years and that younger patients seem to benefit more from the addition of surgery and/or chemotherapy to radiotherapy. Due to the exploratory nature of the study, these results should be confirmed in future prospective trials.


Asunto(s)
Adenocarcinoma/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Células Escamosas/radioterapia , Neoplasias Pulmonares/radioterapia , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Suecia
10.
Anticancer Res ; 32(4): 1339-46, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22493368

RESUMEN

AIM: The aim of the present study was to retrospectively investigate the impact of induction chemotherapy on treatment outcome in patients treated with curatively intended radiotherapy for non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with a diagnosed NSCLC that have been subjected to curatively intended irradiation (≥50 Gy) and treated in an oncology department in Sweden during the years 1990-2000 were included in the study. Operated patients and patients having received concomitant chemotherapy were excluded. The included patients were localised by a manual search of all the oncology departments' medical records and radiation charts. RESULTS: Patients treated with induction chemotherapy (n=79) had a significantly better overall survival compared with patients treated with radiotherapy alone (p=0.0097) in a univariate Cox regression analysis. A platinum/taxane combination produced the greatest survival benefit; hazard ratio=0.49 (95% confidence interval=0.31 to 0.75). CONCLUSION: We found that patients treated with induction chemotherapy in addition to radiotherapy for NSCLC have a better overall survival than patients treated with radiotherapy alone and that the best results are achieved using a platinum/taxane combination.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
11.
Radiother Oncol ; 100(1): 41-8, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21295880

RESUMEN

BACKGROUND AND PURPOSE: Studies on accelerated fractionation (AF) in head and neck cancer have shown increased local control and survival compared with conventional fractionation (CF), while others have been non-conclusive. In 1998 a national Swedish group decided to perform a randomised controlled clinical study of AF. MATERIALS AND METHODS: Patients with verified squamous cell carcinoma of the oral cavity, oropharynx, larynx (except glottic T1-T2, N0) and hypopharynx were included. Patients with prior chemotherapy or surgery were excluded. Patients were randomised to either CF (2Gy/day, 5days/week for 7 weeks, total dose 68Gy) or to AF (1.1Gy+2.0Gy/day, 5days/week for 4.5weeks, total dose 68Gy). An extensive quality assurance protocol was followed throughout the study. The primary end point was loco-regional tumour control (LRC) at two years after treatment. RESULTS: The study was closed in 2006 when 750 patients had been randomised. Eighty-three percent of the patients had stages III-IV disease. Forty eight percent had oropharyngeal, 21% laryngeal, 17% hypopharyngeal and 14% oral cancers. There were no significant differences regarding overall survival (OS) or LRC between the two regimens. The OS at two years was 68% for AF and 67% for CF. The corresponding figures for LRC were 71% and 67%, respectively. There was a trend towards improved LRC for oral cancers treated (p=0.07) and for large tumours (T3-T4) (p=0.07) treated with AF. The AF group had significantly worse acute reactions, while there was no significant increase in late effects. CONCLUSION: Overall the AF regimen did not prove to be more efficacious than CF. However, the trend towards improved results in AF for oral cancers needs to be further investigated.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Fraccionamiento de la Dosis de Radiación , Femenino , Neoplasias de Cabeza y Cuello/mortalidad , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Carcinoma de Células Escamosas de Cabeza y Cuello , Suecia
12.
Acta Oncol ; 50(4): 518-27, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21198416

RESUMEN

BACKGROUND: In SBRT of lung tumours no established relationship between dose-volume parameters and the incidence of lung toxicity is found. The aim of this study is to compare the LQ model and the universal survival curve (USC) to calculate biologically equivalent doses in SBRT to see if this will improve knowledge on this relationship. MATERIAL AND METHODS: Toxicity data on radiation pneumonitis grade 2 or more (RP2+) from 57 patients were used, 10.5% were diagnosed with RP2+. The lung DVHs were corrected for fractionation (LQ and USC) and analysed with the Lyman- Kutcher-Burman (LKB) model. In the LQ-correction α/ß = 3 Gy was used and the USC parameters used were: α/ß = 3 Gy, D(0) = 1.0 Gy, [Formula: see text] = 10, α = 0.206 Gy(-1) and d(T) = 5.8 Gy. In order to understand the relative contribution of different dose levels to the calculated NTCP the concept of fractional NTCP was used. This might give an insight to the questions of whether "high doses to small volumes" or "low doses to large volumes" are most important for lung toxicity. RESULTS AND DISCUSSION: NTCP analysis with the LKB-model using parameters m = 0.4, D(50) = 30 Gy resulted for the volume dependence parameter (n) with LQ correction n = 0.87 and with USC correction n = 0.71. Using parameters m = 0.3, D(50) = 20 Gy n = 0.93 with LQ correction and n = 0.83 with USC correction. In SBRT of lung tumours, NTCP modelling of lung toxicity comparing models (LQ,USC) for fractionation correction, shows that low dose contribute less and high dose more to the NTCP when using the USC-model. Comparing NTCP modelling of SBRT data and data from breast cancer, lung cancer and whole lung irradiation implies that the response of the lung is treatment specific. More data are however needed in order to have a more reliable modelling.


Asunto(s)
Fraccionamiento de la Dosis de Radiación , Modelos Lineales , Neoplasias Pulmonares/radioterapia , Pulmón/efectos de la radiación , Traumatismos por Radiación/etiología , Radiocirugia/efectos adversos , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase II como Asunto , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Pronóstico , Radiografía , Tasa de Supervivencia
13.
J Clin Oncol ; 27(20): 3290-6, 2009 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-19414667

RESUMEN

PURPOSE: The impact of stereotactic body radiotherapy (SBRT) on 3-year progression-free survival of medically inoperable patients with stage I non-small-cell lung cancer (NSCLC) was analyzed in a prospective phase II study. PATIENTS AND METHODS: Fifty-seven patients with T1NOMO (70%) and T2N0M0 (30%) were included between August 2003 and September 2005 at seven different centers in Sweden, Norway, and Denmark and observed up to 36 months. SBRT was delivered with 15 Gy times three at the 67% isodose of the planning target volume. RESULTS: Progression-free survival at 3 years was 52%. Overall- and cancer-specific survival at 1, 2, and 3 years was 86%, 65%, 60%, and 93%, 88%, 88%, respectively. There was no statistically significant difference in survival between patients with T1 or T2 tumors. At a median follow-up of 35 months (range, 4 to 47 months), 27 patients (47%) were deceased, seven as a result of lung cancer and 20 as a result of concurrent disease. Kaplan-Meier estimated local control at 3 years was 92%. Local relapse was observed in four patients (7%). Regional relapse was observed in three patients (5%). Nine patients (16%) developed distant metastases. The estimated risk of all failure (local, regional, or distant metastases) was increased in patients with T2 (41%) compared with those with T1 (18%) tumors (P = .027). CONCLUSION: With a 3-year local tumor control rate higher than 90% with limited toxicity, SBRT emerges as state-of-the-art treatment for medically inoperable stage I NSCLC and may even challenge surgery in operable instances.


Asunto(s)
Neoplasias Pulmonares/cirugía , Radiocirugia/métodos , Carcinoma Pulmonar de Células Pequeñas/cirugía , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Disnea/etiología , Fatiga/etiología , Femenino , Fibrosis/etiología , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Derrame Pleural/etiología , Estudios Prospectivos , Radiocirugia/efectos adversos , Carcinoma Pulmonar de Células Pequeñas/patología , Resultado del Tratamiento
14.
Radiother Oncol ; 88(3): 359-67, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18768228

RESUMEN

BACKGROUND AND AIMS: In a retrospective study using stereotactic body radiotherapy (SBRT) in medically inoperable patients with stage I NSCLC we previously reported a local control rate of 88% utilizing a median dose of 15Gyx3. This report records the toxicity encountered in a prospective phase II trial, and its relation to coexisting chronic obstructive pulmonary disease (COPD) and cardio vascular disease (CVD). MATERIAL AND METHODS: Sixty patients were entered in the study between August 2003 and September 2005. Fifty-seven patients (T1 65%, T2 35%) with a median age of 75 years (59-87 years) were evaluable. The baseline mean FEV1% was 64% and median Karnofsky index was 80. A total dose of 45Gy was delivered in three fractions at the 67% isodose of the PTV. Clinical, pulmonary and radiological evaluations were made at 6 weeks, 3, 6, 9, 12, 18, and 36 months post-SBRT. Toxicity was graded according to CTC v2.0 and performance status was graded according to the Karnofsky scale. RESULTS: At a median follow-up of 23 months, 2 patients had relapsed locally. No grade 4 or 5 toxicity was reported. Grade 3 toxicity was seen in 12 patients (21%). There was no significant decline of FEV1% during follow-up. Low grade pneumonitis developed to the same extent in the CVD 3/17 (18%) and COPD 7/40 (18%) groups. The incidence of fibrosis was 9/17 (53%) and pleural effusions was 8/17 (47%) in the CVD group compared with 13/40 (33%) and 5/40 (13%) in the COPD group. CONCLUSION: SBRT for stage I NSCLC patients who are medically inoperable because of COPD and CVD results in a favourable local control rate with a low incidence of grade 3 and no grade 4 or 5 toxicity.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Enfermedades Cardiovasculares/complicaciones , Neoplasias Pulmonares/radioterapia , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Radiocirugia/métodos , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/fisiopatología , Distribución de Chi-Cuadrado , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/fisiopatología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Dosificación Radioterapéutica , Pruebas de Función Respiratoria , Estudios Retrospectivos , Resultado del Tratamiento
15.
Radiother Oncol ; 87(2): 290-9, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18206256

RESUMEN

AIM: This paper describes the quality assurance (QA) work performed in the Swedish multicenter ARTSCAN (Accelerated RadioTherapy of Squamous cell CArcinomas in the head and Neck) trial to guarantee high quality in a multicenter study which involved modern radiotherapy such as 3DCRT or IMRT. MATERIALS AND METHODS: The study was closed in June 2006 with 750 randomised patients. Radiation therapy-related data for every patient were sent by each participating centre to the QA office where all trial data were reviewed, analysed and stored. In case of any deviation from the protocol, an interactive process was started between the QA office and the local responsible clinician and/or physicist to increase the compliance to the protocol for future randomised patients. Meetings and workshops were held on a regular basis for discussions on various trial-related issues and for the QA office to report on updated results. RESULTS AND DISCUSSION: This review covers the 734 patients out of a total of 750 who had entered the study. Deviations early in the study were corrected so that the overall compliance to the protocol was very high. There were only negligible variations in doses and dose distributions to target volumes for each specific site and stage. The quality of the treatments was high. Furthermore, an extensive database of treatment parameters was accumulated for future dose-volume vs. endpoint evaluations. CONCLUSIONS: This comprehensive QA programme increased the probability to draw firm conclusions from our study and may serve as a concept for QA work in future radiotherapy trials where comparatively small effects are searched for in a heterogeneous tumour population.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Garantía de la Calidad de Atención de Salud , Radioterapia Conformacional/normas , Radioterapia de Intensidad Modulada/normas , Femenino , Humanos , Masculino , Dosificación Radioterapéutica , Suecia , Resultado del Tratamiento
16.
Acta Oncol ; 45(7): 787-95, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16982541

RESUMEN

We reviewed results of SBRT treatment of 138 patients with medically inoperable stage I NSCLC treated during 1996-2003 at five different centres in Sweden and Denmark. Mean age was 74 years (range 56-90) with 69 men and 72 women. SBRT was delivered using a 3D conformal multifield technique and a stereotactic body frame. Doses delivered were 30-48 Gy (65% isodose at the periphery of planning target volume, PTV) in 2-4 fractions. Equivalent dose in 2 Gy fractions (EQD2) was in the range of 50-100 Gy. Mean gross tumour volume (GTV) was 39 cm3 (2-436), and planning target volume was 101 cm3 (11-719). Overall response rate (CR, PR) was 61% (84/138). SD was noted in 36% (50/138). During a median follow-up period of 33 months (1-107), 16 (12%) local failures occurred, ten of which also included distant metastases. Local failure was associated with tumour size, target definition and central or pleura proximity. Distant metastases occurred in 25% (35/138) of the patients. Ninety-one (65%) patients died during follow-up of which 55 patients (60%) died of other causes than lung cancer. Three- and 5-year overall survival was 52 and 26% respectively. Lung cancer specific 3- and 5-year overall survival was 66 and 40% respectively. Fifty nine percent (83/138) of the patients had no side effects. Fourteen patients experienced grade 3-4 toxicity according to radiation therapy oncology group (RTOG). EQD2 (> v.s.<55.6 Gy) showed a statistically significant benefit survival for the higher doses. SBRT for stage I NSCLC results in favourable local control not inferior to fractionated RT and with acceptable toxicity.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Neoplasias Pulmonares/cirugía , Radiocirugia/métodos , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Dinamarca/epidemiología , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia/terapia , Recurrencia Local de Neoplasia/mortalidad , Probabilidad , Estudios Retrospectivos , Análisis de Supervivencia , Suecia/epidemiología , Insuficiencia del Tratamiento , Resultado del Tratamiento
17.
Acta Oncol ; 45(7): 973-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16982566

RESUMEN

In forthcoming multicentre studies on stereotactic body radiotherapy (SBRT) compliance with volume and dose prescriptions will be mandatory to avoid unnecessary heterogeneity bias. To evaluate compliance in a multicentre setting we used two cases from an ongoing phase II study of SBRT of T1-T2N0M0 inoperable NSCLC in a dummy run oriented on volumes and doses. Six Scandinavian centres participated. Each centre received CT-scans covering the whole lung volumes of two patients with instructions to follow the study protocol when outlining tumour and target volumes, prescribing doses and creating dose plans. Volumes and doses of the 12 dose plans were evaluated according to the study protocol. For the two patients the GTV volume range was 24 to 39 cm3 and 26 to 41 cm3, respectively. The PTV volume range was 90 to 116 cm3, and 112 to 155 cm3, respectively. For all plans the margin between CTV and PTV in all directions followed in detail the protocol. The prescribed dose was for all centres 45 Gy/3 fractions (isocentre dose about 66 Gy). The mean GTV doses ranged from 63 to 67 Gy and from 63 to 68 Gy, respectively. The minimum doses for GTV were between 50-64 Gy and between 55-65 Gy, respectively. The dose distribution was conformed to PTV for 10 of 12 plans and 2 of 12 plans from one centre had sub-optimal dose distribution. Most of the volume and dose parameters for the participating centres showed fully acceptable compliance with the study protocol.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/cirugía , Adhesión a Directriz/organización & administración , Neoplasias Pulmonares/cirugía , Radiocirugia/métodos , Carcinoma de Pulmón de Células no Pequeñas/patología , Ensayos Clínicos Fase II como Asunto , Humanos , Neoplasias Pulmonares/patología , Estadificación de Neoplasias , Dosis de Radiación , Planificación de la Radioterapia Asistida por Computador , Carga Tumoral
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