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1.
BMC Cancer ; 20(1): 402, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32384918

RESUMO

BACKGROUND: Our aim is to report treatment efficacy and toxicity of patients treated by robotic (Cyberknife®) stereotactic body radiotherapy (SBRT) for oligorecurrent lung metastases (ORLM). Additionally we wanted to evaluate influence of tumor, patient and treatment related parameters on local control (LC), lung and distant progression free- (lung PFS/Di-PFS) and overall survival (OS). METHODS: Consecutive patients with up to 5 ORLM (confirmed by FDG PET/CT) were included in this study. Intended dose was 60Gy in 3 fractions (prescribed to the 80% isodose volume). Patients were followed at regular intervals and tumor control and toxicity was prospectively scored. Tumor, patient and treatment data were analysed using competing risk- and Cox regression. RESULTS: Between May 2010 and March 2016, 104 patients with 132 lesions were irradiated from primary lung carcinoma (47%), gastro-intestinal (34%) and mixed primary histologies (19%). The mean tumor volume was 7.9 cc. After a median follow up of 22 months, the 1, 2 and 3 year LC rate (per lesion) was 89.3, 80.0 and 77.8% respectively. The corresponding (per patient) 1, 2 and 3 years lung PFS were 66.3, 50.0, 42.6%, Di-PFS were 80.5, 64.4, 60.6% and OS rates were 92.2, 80.9 and 72.0% respectively. On univariable analysis, gastro-intestinal (GI) as primary tumor site showed a significant superior local control versus the other primary tumor sites. For OS, significant variables were primary histology and primary tumor site with a superior OS for patients with metastases of primary GI origin. LC was significantly affected by the tumor volume, physical and biologically effective dose coverage. Significant variables in multivariable analysis were BED prescription dose for LC and GI as primary site for OS. The vast majority of patients developed no toxicity or grade 1 acute and late toxicity. Acute and late grade 3 radiation pneumonitis (RP) was observed in 1 and 2 patients respectively. One patient with a centrally located lesion developed grade 4 RP and died due to possible RT-induced pulmonary hemorrhage. CONCLUSIONS: SBRT is a highly effective local therapy for oligorecurrent lung metastases and could achieve long term survival in patients with favourable prognostic features.

2.
Br J Radiol ; 93(1107): 20190879, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31804145

RESUMO

OBJECTIVE: Locally recurrent disease is of increasing concern in (non-)small cell lung cancer [(N)SCLC] patients. Local reirradiation with photons or particles may be of benefit to these patients. In this multicentre in silico trial performed within the Radiation Oncology Collaborative Comparison (ROCOCO) consortium, the doses to the target volumes and organs at risk (OARs) were compared when using several photon and proton techniques in patients with recurrent localised lung cancer scheduled to undergo reirradiation. METHODS: 24 consecutive patients with a second primary (N)SCLC or recurrent disease after curative-intent, standard fractionated radio(chemo)therapy were included in this study. The target volumes and OARs were centrally contoured and distributed to the participating ROCOCO sites. Remaining doses to the OARs were calculated on an individual patient's basis. Treatment planning was performed by the participating site using the clinical treatment planning system and associated beam characteristics. RESULTS: Treatment plans for all modalities (five photon and two proton plans per patient) were available for 22 patients (N = 154 plans). 3D-conformal photon therapy and double-scattered proton therapy delivered significantly lower doses to the target volumes. The highly conformal techniques, i.e., intensity modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT), CyberKnife, TomoTherapy and intensity-modulated proton therapy (IMPT), reached the highest doses in the target volumes. Of these, IMPT was able to statistically significantly decrease the radiation doses to the OARs. CONCLUSION: Highly conformal photon and proton beam techniques enable high-dose reirradiation of the target volume. They, however, significantly differ in the dose deposited in the OARs. The therapeutic options, i.e., reirradiation or systemic therapy, need to be carefully weighed and discussed with the patients. ADVANCES IN KNOWLEDGE: Highly conformal photon and proton beam techniques enable high-dose reirradiation of the target volume. In light of the abilities of the various highly conformal techniques to spare specific OARs, the therapeutic options need to be carefully weighed and patients included in the decision-making process.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Recidiva Local de Neoplasia/radioterapia , Órgãos em Risco/efeitos da radiação , Fótons/uso terapêutico , Terapia com Prótons/métodos , Reirradiação/métodos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Conjuntos de Dados como Assunto , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Órgãos em Risco/diagnóstico por imagem , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Resultado do Tratamento
3.
Clin Transl Radiat Oncol ; 17: 40-46, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31193619

RESUMO

Aim: To provide an overview of Radiation Oncology (RO) teaching to medical students around Europe. Materials and methods: An electronic survey was sent to European academic teachers of RO. The survey focused on the teaching of RO to medical students throughout their undergraduate education. Results: A total of 87 academic RO teachers from 29 countries were invited to participate in the electronic survey. Thirty-two surveys were completed by respondents from 19 European countries (response rate: 37%). The median number of hours devoted to RO teaching was 10 h (mean 16 h, range 2-60). The number of hours assigned to RO teaching was equal or inferior compared to medical oncology. In two institutions (6%) RO was delivered as a stand-alone course with an individual knowledge assessment. In 30 institutions (94%), the RO course was taught and/or assessed in a modular curriculum with other disciplines. Radiobiology, breast, lung, gastrointestinal, gynecologic malignancies, RO adverse events and palliative RO were taught in 80% of institutions. Pediatric RO, RO for benign conditions and economic topics were taught in less than 30% of institutions. In most institutions, classical written and oral examinations were used. Computer-based examinations and/or objective structured clinical examinations (OSCE) were seldom used. E-learning methods were available in less than 10% of institutions. A clerkship in RO department was available in 28 out of 32 institutions (87%), less than 5% of medical students were involved in research in RO during their undergraduate education. Strategies to encourage medical students to consider RO as a future career were offered in 53% of institutions. Conclusions: RO teaching to medical students was not uniform in Europe. RO teaching during undergraduate education in Europe was undervalued, and its knowledge and learning tools could be broadened and updated in the core curricula of medical students.

4.
Radiother Oncol ; 128(1): 139-146, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29545019

RESUMO

PURPOSE: To compare dose to organs at risk (OARs) and dose-escalation possibility for 24 stage I non-small cell lung cancer (NSCLC) patients in a ROCOCO (Radiation Oncology Collaborative Comparison) trial. METHODS: For each patient, 3 photon plans [Intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT) and CyberKnife], a double scattered proton (DSP) and an intensity-modulated carbon-ion (IMIT) therapy plan were created. Dose prescription was 60 Gy (equivalent) in 8 fractions. RESULTS: The mean dose and dose to 2% of the clinical target volume (CTV) were lower for protons and ions compared with IMRT (p < 0.01). Doses to the lungs, heart, and mediastinal structures were lowest with IMIT (p < 0.01), doses to the spinal cord were lowest with DSP (p < 0.01). VMAT and CyberKnife allowed for reduced doses to most OARs compared with IMRT. Dose escalation was possible for 8 patients. Generally, the mediastinum was the primary dose-limiting organ. CONCLUSION: On average, the doses to the OARs were lowest using particles, with more homogenous CTV doses. Given the ability of VMAT and CyberKnife to limit doses to OARs compared with IMRT, the additional benefit of particles may only be clinically relevant in selected patients and thus should be carefully weighed for every individual patient.


Assuntos
Carbono/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Radioterapia com Íons Pesados/métodos , Neoplasias Pulmonares/radioterapia , Fótons/uso terapêutico , Terapia com Prótons/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Relação Dose-Resposta à Radiação , Humanos , Neoplasias Pulmonares/patologia , Mediastino/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
5.
Radiol Oncol ; 51(2): 178-186, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28740453

RESUMO

BACKGROUND: Authors report clinical outcomes of patients treated with robotic stereotactic body radiotherapy (SBRT) for primary, recurrent and metastatic lung lesions. PATIENTS AND METHODS: 130 patients with 160 lesions were treated with Cyberknife SBRT, including T1-3 primary lung cancers (54%), recurrent tumors (22%) and pulmonary metastases (24%). The mean biologically equivalent dose (BED10Gy) was 151 Gy (72-180 Gy). Median prescribed dose for peripheral and central lesions was 3×20 Gy and 3×15 Gy, respectively. Local control (LC), overall survival (OS), and cause-specific survival (CSS) rates, early and late toxicities are reported. Statistical analysis was performed to identify factors influencing local tumor control. RESULTS: Median follow-up time was 21 months. In univariate analysis, higher dose was associated with better LC and a cut-off value was detected at BED10Gy ≤ 112.5 Gy, resulting in 1-, 2-, and 3-year actuarial LC rates of 93%, vs 73%, 80% vs 61%, and 63% vs 54%, for the high and low dose groups, respectively (p = 0.0061, HR = 0.384). In multivariate analysis, metastatic origin, histological confirmation and larger Planning Target Volume (PTV) were associated with higher risk of local failure. Actuarial OS and CSS rates at 1, 2, and 3 years were 85%, 74% and 62%, and 93%, 89% and 80%, respectively. Acute and late toxicities ≥ Gr 3 were observed in 3 (2%) and 6 patients (5%), respectively. CONCLUSIONS: Our favorable LC and survival rates after robotic SBRT, with low rates of severe toxicities, are coherent with the literature data in this mixed, non-selected study population.

6.
Clin Colorectal Cancer ; 16(4): 349-357.e1, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28462852

RESUMO

BACKGROUND: The purpose of this study was to analyze local control (LC), liver progression-free survival (PFS), and distant PFS (DFS), overall survival (OS), and toxicity in a cohort of patients treated with stereotactic body radiotherapy (SBRT) with fiducial tracking for oligorecurrent liver lesions; and to evaluate the potential influence of lesion size, systemic treatment, physical and biologically effective dose (BED), treatment calculation algorithms and other parameters on the obtained results. PATIENTS AND METHODS: Unoperable patients with sufficient liver function had [18F]-fluorodeoxyglucose-positron emission tomography-computed tomography and liver magnetic resonance imaging to confirm the oligorecurrent nature of the disease and to further delineate the gross tumor volume (GTV). An intended dose of 45 Gy in 3 fractions was prescribed on the 80% isodose and adapted if risk-related. Treatment was executed with the CyberKnife system (Accuray Inc) platform using fiducials tracking. Initial plans were recalculated using the Monte Carlo algorithm. Patient and treatment data were processed using the Kaplan-Meier method and log rank test for survival analysis. RESULTS: Between 2010 and 2015, 42 patients (55 lesions) were irradiated. The mean GTV and planning target volume (PTV) were 30.5 cc and 96.8 cc, respectively. Treatments were delivered 3 times per week in a median of 3 fractions to a PTV median dose of 54.6 Gy. The mean GTV and PTV D98% were 51.6 Gy and 51.2 Gy, respectively. Heterogeneity corrections did not influence dose parameters. After a median follow-up of 18.9 months, the 1- and 2-year LC/liver PFS/DFS/OS were 81.3%/55%/62.4%/86.9%, and 76.3%/42.3%/52%/78.3%, respectively. Performance status and histology had a significant effect on LC, whereas age (older than 65 years) marginally influenced liver PFS. Clinical target volume physical dose V45 Gy > 95%, generalized equivalent uniform dose (a = -30) > 45 Gy and a BED (α/ß = 10) V105 Gy > 96% showed statistically significant effect on the LC. Acute Grade 3 gastrointestinal (GI) and late Grade 2 GI and fatigue toxicity were found in 5% and 11% patients, respectively. CONCLUSION: Favorable survival and toxicity results support the potential paradigm shift in which the use of SBRT in oligorecurrent liver disease could benefit patients with unresectable or resectable liver metastases.


Assuntos
Neoplasias Hepáticas/radioterapia , Imagem por Ressonância Magnética/métodos , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Fluordesoxiglucose F18 , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Método de Monte Carlo , Recidiva Local de Neoplasia , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
7.
Eur J Nucl Med Mol Imaging ; 43(8): 1453-60, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26830299

RESUMO

INTRODUCTION: With (18)F-FDG PET/CT, tumor uptake intensity and heterogeneity have been associated with outcome in several cancers. This study aimed at investigating whether (18)F-FDG uptake intensity, volume or heterogeneity could predict the outcome in patients with non-small cell lung cancers (NSCLC) treated by stereotactic body radiation therapy (SBRT). METHODS: Sixty-three patients with NSCLC treated by SBRT underwent a (18)F-FDG PET/CT before treatment. Maximum and mean standard uptake value (SUVmax and SUVmean), metabolic tumoral volume (MTV), total lesion glycolysis (TLG), as well as 13 global, local and regional textural features were analysed. The predictive value of these parameters, along with clinical features, was assessed using univariate and multivariate analysis for overall survival (OS), disease-specific survival (DSS) and disease-free survival (DFS). Cutoff values were obtained using logistic regression analysis, and survivals were compared using Kaplan-Meier analysis. RESULTS: The median follow-up period was 27.1 months for the entire cohort and 32.1 months for the surviving patients. At the end of the study, 25 patients had local and/or distant recurrence including 12 who died because of the cancer progression. None of the clinical variables was predictive of the outcome, except age, which was associated with DFS (HR 1.1, P = 0.002). None of the (18)F-FDG PET/CT or clinical parameters, except gender, were associated with OS. The univariate analysis showed that only dissimilarity (D) was associated with DSS (HR = 0.822, P = 0.037), and that several metabolic measurements were associated with DFS. In multivariate analysis, only dissimilarity was significantly associated with DSS (HR = 0.822, P = 0.037) and with DFS (HR = 0.834, P < 0.01). CONCLUSION: The textural feature dissimilarity measured on the baseline (18)F-FDG PET/CT appears to be a strong independent predictor of the outcome in patients with NSCLC treated by SBRT. This may help selecting patients who may benefit from closer monitoring and therapeutic optimization.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Fluordesoxiglucose F18 , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Radiocirurgia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento
8.
Acta Oncol ; 54(9): 1558-66, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26406152

RESUMO

BACKGROUND: To evaluate efficacy and toxicity of radio-chemotherapy (RCT) and MR-guided pulsed-dose-rate (PDR) adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC). MATERIAL AND METHODS: Between 2007 and 2014 85 patients with FIGO stage 1B1 N+ or ≥ 1B2 cervical cancer were treated with RCT+ IGABT. The treatment consisted of a pelvic± paraaortic external beam radiotherapy (EBRT) (45-50.4 Gy ± 10 Gy boost to primary tumor and/or to pathologic lymph nodes) with concurrent cisplatin followed by 25-35 Gy of PDR IGABT in 30-50 pulses. The ratio of 3D-CFRT/IMRT was 61/24 patients. Dose-volume parameters of high-risk clinical target volume (HR-CTV), intermediate-risk clinical target volume (IR-CTV) and D2cm(3) organs at risk (OARs) were reported. Local control (LC), cancer-specific survival (CCS) and overall survival (OS) were analyzed actuarially and morbidity crude rates were scored using CTCAEv4.0. RESULTS: Mean follow-up was 36 months (range 6-94). The mean D90 and D98 for HR-CTV was 84.4 ± 9 Gy and 77 ± 8.1 Gy, while for IR-CTV was 69.1 ± 4.3 Gy and 64.8 ± 4.3 Gy, respectively. The mean D2cm(3) for OARs was the following: bladder: 77.3 ± 10.5 Gy, rectum: 65 ± 6.8 Gy, sigmoid: 63 ± 7.9 Gy and intestine: 64.0 ± 9.1 Gy. Three year LC, CSS and OS were: 94%, 85% and 81%. The three-year regional- and distant control rates were 95% and 74%. Node negative patients had significantly higher three-year CSS (100 vs. 72%, p = 0.016) and OS (92 vs. 72%, p = 0.001) compared to node positive ones. Three-year actuarial late Grade ≥ 3 morbidity was the following: GI: 8%, GU: 5%, Vaginal: 8%. The frequency of Grade ≥ 3 hematological toxicities including anemia/leukopenia/neutropenia/thrombocytopenia were 8.6%/34.7%/24.3%/24.3%, respectively. CONCLUSION: This large mono-institutional experience builds up further evidences that IGABT in conjunction with RCT should be the standard of care for patients suffering LACC.


Assuntos
Braquiterapia/métodos , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Radioterapia de Intensidade Modulada , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Braquiterapia/efeitos adversos , Carcinoma de Células Escamosas/secundário , Quimiorradioterapia/efeitos adversos , Cisplatino/efeitos adversos , Colo Sigmoide , Fracionamento da Dose de Radiação , Feminino , Doenças Hematológicas/etiologia , Humanos , Metástase Linfática , Imagem por Ressonância Magnética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Órgãos em Risco , Doses de Radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Reto , Taxa de Sobrevida , Resultado do Tratamento , Carga Tumoral , Bexiga Urinária , Neoplasias do Colo do Útero/patologia
9.
Pathol Oncol Res ; 21(4): 1051-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25840562

RESUMO

To analyze respiratory motion of surgical clips, chest wall (CW) and the anterior displacement of the heart and its impact on heart dosimetry between prone (Pr) and supine (Su) positions during whole breast radiotherapy after breast conserving surgery. Sixteen patients underwent 4D-CT for radiotherapy planning in Pr and Su positions. Maximum inhale and maximum exhale phases were analyzed. Mean 3D vectorial displacements ± standard deviations (SD) of the surgical clips were measured. Volumetric changes of the CW were recorded and compared. Cardiac displacement was assessed by a volume between the inner surface of CW and the myocardium of the heart (CW/H-V). For left-sided cases, comparative dosimetry was performed in each position simulating no- (Pr-noC, Su-noC) versus daily correction protocols (Pr-C, Su-C). The movements of 81 surgical clips were analyzed. Prone positioning significantly reduced both the mean 3D vectorial displacements (1.1 ± 0.6 (Pr) vs. 2.0 ± 0.9 mm (Su), p < 0.01) and their variability (0.3 ± 0.2 vs. 0.5 ± 0.3 mm, p = 0.01). Respiration-induced volumetric changes of CW were also significantly lower in Pr (2.3 ± 4.9 vs. 9.6 ± 7.1 cm(3), p < 0.01). The CW/H-V was significantly smaller in Pr than in Su (39.9 ± 14.6 vs. 64.3 ± 28.2 cm(3), p < 0.01). Besides identical target coverage heart, left-anterior-descending coronary artery (LADCA) and ipsilateral lung dose parameters were lowered with Pr-C compared to Pr-noC, Su-C and Su-noC. Prone position significantly reduced respiration-related surgical clip movements, their variability as well as CW movements. Significant anterior heart displacement was observed in Pr. Prone position with daily online correction could maximize the heart and LADCA protection.


Assuntos
Coração/efeitos da radiação , Pulmão/efeitos da radiação , Decúbito Ventral/fisiologia , Respiração/efeitos da radiação , Decúbito Dorsal/fisiologia , Adulto , Idoso , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Vasos Coronários/efeitos da radiação , Feminino , Humanos , Mastectomia Segmentar/métodos , Pessoa de Meia-Idade , Radiometria/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos
10.
Anticancer Res ; 31(12): 4417-22, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22199309

RESUMO

BACKGROUND/AIM: Artenimol-R is cytotoxic in transformed cervical cells and safety in humans is yet to be established. The present study investigates the clinical benefits, safety and the tumor marker effect of orally administered Artenimol-R in patients with advanced cervix carcinoma. PATIENTS AND METHODS: Ten patients were treated with Artenimol-R for 28 days. Clinical symptoms, vaginal discharge and pain were followed-up. Adverse events were recorded. Biopsy samples were analyzed by immunohistochemistry for the expression of relevant tumor markers. RESULTS: Artenimol-R treatment induced clinical remission with a median time for the disappearance of the symptoms being 7 days. No adverse events of grade 3 or 4 occurred. The expression of p53, Epidermal growth factor receptor (EGFR), and antigen Ki-67 as a cellular marker of proliferation, as well as the number of blood vessels stained by the CD31 antibody decreased, whereas the expression of transferrin receptor protein 1 (CD71) increased. CONCLUSION: The current pilot study provides evidence on the improvement of the clinical symptoms and the good tolerability of Artenimol-R in patients with advanced carcinoma of the cervix uteri. A survival trial with Artenimol-R in advanced patients is warranted.


Assuntos
Antineoplásicos/uso terapêutico , Artemisininas/uso terapêutico , Biomarcadores Tumorais/metabolismo , Carcinoma/tratamento farmacológico , Neoplasias do Colo do Útero/tratamento farmacológico , Administração Oral , Adulto , Idoso , Antígenos CD/biossíntese , Receptores ErbB/metabolismo , Feminino , Seguimentos , Humanos , Imuno-Histoquímica/métodos , Antígeno Ki-67/biossíntese , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Receptores da Transferrina/biossíntese , Indução de Remissão , Resultado do Tratamento
11.
Int J Radiat Oncol Biol Phys ; 76(1): 269-76, 2010 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-19775833

RESUMO

PURPOSE: We compared the dose conformity of two radiation modalities: high-dose-rate brachytherapy (HDR BT) and intensity-modulated radiation therapy (IMRT) to deliver a boost to the prostate after external beam radiotherapy (EBRT). METHODS AND MATERIALS: Ten successive patients with prostate adenocarcinoma treated with a single 10-Gy HDR BT boost after EBRT were investigated. Four theoretical IMRT plans were computed: (a) 32.85 Gy IMRT and (b) 26 Gy IMRT with CTV-PTV expansions, doses corresponding to the equivalent dose in 2-Gy fractions (EQD2) of one 10-Gy fraction calculated with a prostate alpha/beta ratio of respectively 1.5 and 3 Gy; and (c) 32.85 Gy IMRT and (d) 26 Gy IMRT without CTV-PTV expansions. The dose-volume histogram values converted in EQD2 with an alpha/beta ratio of 3 Gy for the organs at risk were compared. RESULTS: The HDR BT plan delivered higher mean doses to the PTV compared with IMRT plans. In all, 33% of the rectal volume received a mean dose of 5.32 +/- 0.65 Gy and 20% of bladder volume received 4.61 +/- 1.24 Gy with HDR BT. In comparison, doses delivered with IMRT were respectively 13.4 +/- 1.49 Gy and 10.81 +/- 4 Gy, even if only 26 Gy was prescribed to the PTV with no CTV-PTV expansion (p < 0.0001). The hot spots inside the urethra were greater with HDR BT but acceptable. CONCLUSIONS: Use of HDR BT produced a more conformal plan for the boost to the prostate than IMRT even without CTV-PTV expansions.


Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Humanos , Masculino , Movimento , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Reto/efeitos da radiação , Carga Tumoral , Uretra/efeitos da radiação , Bexiga Urinária/efeitos da radiação
12.
Strahlenther Onkol ; 185(11): 736-42, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19899007

RESUMO

BACKGROUND AND PURPOSE: Dose escalation in order to improve the biochemical control in prostate cancer requires the application of irradiation techniques with high conformality. The dosimetric selectivity of three radiation modalities is compared: high-dose-rate brachytherapy (HDR-BT), intensity-modulated radiation radiotherapy (IMRT), and helical tomotherapy (HT). PATIENTS AND METHODS: Ten patients with prostate adenocarcinoma treated by a 10-Gy HDR-BT boost after external-beam radiotherapy were investigated. For each patient, HDR-BT, IMRT and HT theoretical treatment plans were realized using common contour sets. A 10-Gy dose was prescribed to the planning target volume (PTV). The PTVs and critical organs' dose-volume histograms obtained were compared using Student's t-test. RESULTS: HDR-BT delivers spontaneously higher mean doses to the PTV with smaller cold spots compared to IMRT and HT. 33% of the rectal volume received a mean HDR-BT dose of 3.86 + or - 0.3 Gy in comparison with a mean IMRT dose of 6.57 + or - 0.68 Gy and a mean HT dose of 5.58 + or - 0.71 Gy (p < 0.0001). HDR-BT also enables to better spare the bladder. The hot spots inside the urethra are greater with HDR-BT. The volume of healthy tissue receiving 10% of the prescribed dose is reduced at least by a factor of 8 with HDR-BT (p < 0.0001). CONCLUSION: HDR-BT offers better conformality in comparison with HT and IMRT and reduces the volume of healthy tissue receiving a low dose.


Assuntos
Adenocarcinoma/radioterapia , Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Adenocarcinoma/patologia , Humanos , Masculino , Neoplasias da Próstata/patologia , Lesões por Radiação/etiologia , Dosagem Radioterapêutica , Reto/efeitos da radiação , Uretra/efeitos da radiação
13.
Int J Radiat Oncol Biol Phys ; 67(4): 1052-8, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17336215

RESUMO

PURPOSE: The aim of this study was to use permanent seed implants in the breast and describe our experience with 15 cases, using iodine seed implants as a tumor bed boost. METHODS AND MATERIALS: Breasts were fixed with a thermoplastic sheet, a template bridge applied, the thorax scanned and the images rotated to be perpendicular to the implant axis. Skin, heart, and lung were delineated. A preplan was made, prescribing 50 Gy to the clinical target volume (CTV), consisting in this boost series of nearly a quadrant. Iodine (125) seeds were stereotactically implanted through the template, and results were checked with a postplan computed tomographic (CT) scan. RESULTS: The breast was immobilized reproducibly. Simulation, scanning, and implant were performed without difficulties. Preplan CTV D90% (the dose delivered to 90% of the CTV) was 66 Gy, and postoperative fluoroscopic or CT scan checks were satisfactory. Pre- and postplan dose-volume histogram showed good organ sparing: mean postplan skin, heart, and lung V30 Gy (the organ volume receiving a dose of 30 Gy) of 2 +/- 2.2 mL, 0.24 +/- 0.34 mL, and 3.5 +/- 5 mL, respectively. No short-term toxicity above Grade 1 was noted, except for transient Grade 3 neuropathy in 1 patient. CONCLUSIONS: Seeds remained in the right place, as assessed by fluoroscopy, absence of significant pre- to postplan dose-volume histogram change for critical organs, and total irradiated breast volume. The method could be proposed as a boost when high dosimetric selectivity is required (young patients after cardiotoxic chemotherapy for left-sided cancer). This boost series was a preliminary step before testing partial breast irradiation by permanent seed implant in a prospective trial.


Assuntos
Braquiterapia/métodos , Neoplasias da Mama/radioterapia , Adulto , Idoso , Algoritmos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Pessoa de Meia-Idade , Lesões por Radiação/prevenção & controle , Radiografia , Técnicas Estereotáxicas
14.
Radiother Oncol ; 79(3): 329-34, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16780976

RESUMO

BACKGROUND AND PURPOSE: To evaluate on 201 locally advanced prostatic cancers prospectively treated in a phase II trial, the efficacy of a combination of external beam radiotherapy (39.6 Gy) and (192)Ir low dose rate brachytherapy (Bt) (40-45 Gy). PATIENTS AND METHODS: Sixty-four patients were included in the intermediate prognosis group with only one of the following adverse factors (PSA > 10 ng/ml, Gleason score > or = 7 or clinical stage > or =T2b) and 137 in the unfavourable group when at least two of these factors were present. RESULTS: The actuarial 4 years biochemical no evidence of disease is 82.8% for the entire population. It is, respectively, 97 and 76% in the intermediate and unfavourable prognosis groups (P < 0.0001). Grade > or =3 late urinary complications occurred in 13 patients (6.5%). Eight patients (4%) presented late grade 2 rectal complications but no grades 3-5 was observed. CONCLUSIONS: Even if an alpha/beta of 1.5-3 Gy theoretically favours the use of a high dose rate mode of irradiation, the early results presented here are as good as those reported for similar groups of patients with high dose rate treatments. Late toxicity is identical but our urinary toxicity is within the less favourable and rectal toxicity within the most favourable results. We can postulate that while inducing very high hyperdosage regions (V150) mainly focused on the peripheral zone, most of the Bt techniques consist of a more ablative treatment. Many of the radiobiological studies on Bt did not in fact take into account the heterogeneity of irradiation inside the CTV. This study highlights the need to explore pulsed dose rate therapies, permanent implant and new available radioisotopes such as (169)Ytterbium that will offer the safety of low and lower dose rates. The actual late toxicity of the different Bt techniques is not yet inexistent indeed.


Assuntos
Braquiterapia/métodos , Radioisótopos de Irídio/uso terapêutico , Neoplasias da Próstata/radioterapia , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Progressão da Doença , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Resultado do Tratamento
15.
Radiother Oncol ; 78(1): 47-52, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16216365

RESUMO

PURPOSE: This work aims at comparing the dosimetric possibilities of 125I or 192Ir prostate brachytherapy (Bt) as a boost to external beam radiotherapy in the treatment of locally advanced adenocarcinoma. METHODS AND MATERIALS: From 1/1997 to 12/2002, 260 patients were treated. Until 12/2001 a low dose rate (LDR) treatment with 192Ir wires was used, later replaced by a high dose rate (HDR) delivered with an 192Ir stepping source technology. For the present work, we selected 40 patients including the last 20 treated, respectively, by LDR and HDR. The planning CT Scans of all these 40 patients were transferred into the 3D Prowess system for 125I permanent implants design according to the Seattle method. The reference data for dosimetric comparisons were the V100 and the prescribed dose for 192Ir as well as the dose delivered with 125I techniques to the 192Ir V100. We compared V100-150 data as well as doses to the organs at risks (OR) and cold spots (CS). RESULTS: The V100 is 85.3+/-8% for 192Ir LDR and 96+/-2% for HDR techniques (P < 0.0001). In comparison with 125I, the 192Ir LDR mode induces higher hyperdosage volumes inside the CTV but also more CS, while maximal doses to urethra and rectum are, respectively, 17 and 39% less with 125I (P < 0.0001). In comparison with the 192Ir HDR mode, 125I Bt induces higher hyperdosage volumes and slightly more CS deliberately planned around the bladder neck. If delivered doses to urethra are identical, those to the 20% anterior part of the rectum are 33% less with 125I (P < 0,0001). The 125I Bt technique was only possible in 24 out of the 40 patients studied due to pelvic bone arch interference. CONCLUSIONS: At the present time, there is no evident dosimetric superiority of one Bt method when all the criteria are taken into account. However, improving Bt techniques to implant any prostatic size could found the superiority of the 125I or permanent implants. 125I indeed allows large hyperdosage volumes inside the CTV in comparison with 192Ir HDR techniques while lowering doses to OR and minimizing CS.


Assuntos
Adenocarcinoma/radioterapia , Braquiterapia/métodos , Radioisótopos do Iodo/uso terapêutico , Radioisótopos de Irídio/uso terapêutico , Neoplasias da Próstata/radioterapia , Terapia Combinada , Relação Dose-Resposta à Radiação , Humanos , Masculino , Dosagem Radioterapêutica , Radioterapia Assistida por Computador
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