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1.
Clin. transl. oncol. (Print) ; 20(10): 1329-1336, oct. 2018. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-173721

RESUMO

Objectives: This study was to evaluate the feasibility of simultaneous integrated boost on tumor hypoxia area by studying the dosimetric change of hypoxia imaging guidance on intensity-modulated radiation therapy for non-small cell lung cancer (NSCLC). Methods: Five NSCLC patients with large hypoxic volume participated in this study. FDG PET/CT images were fused with CT localization images to delineate gross tumor volume. FMISO PET/CT images were fused with CT localization images to delineate hypoxic biological target volume (BTV) (tissue maximum ratio ≥ 1.3) by threshold. BTV was irradiated with 72, 78 and 84 Gy, respectively, 30 times. The dosimetry differences were compared in target volume and organ at risk between simultaneous integrated boost plans and conventional radiotherapy plans. Results: Dosages on BTV of NSCLC hypoxic area were increased to 72, 78 and 84 Gy, respectively, by simultaneous integrated boost intensity-modulated radiation therapy. There was no obvious difference in dosage distributions on original target volume compared with those in conventional radiotherapy. Dosages on main organ at risk in chest met the dosimetric constraint, and there was no significant difference compared with those in conventional radiotherapy. Conclusion: It is feasible in dosiology that the dosages in NSCLC hypoxic area were added to 72, 78 and 84 Gy by simultaneous integrated boost with the guidance of 18F-FMISO PET/CT


No disponible


Assuntos
Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radioterapia de Intensidade Modulada/métodos , Radiometria/métodos , Hipóxia Tumoral/efeitos da radiação , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Doses de Radiação , Fluordesoxiglucose F18/administração & dosagem , Tomografia por Emissão de Pósitrons/métodos
2.
Clin. transl. oncol. (Print) ; 20(9): 1127-1135, sept. 2018. tab
Artigo em Inglês | IBECS | ID: ibc-173697

RESUMO

Sarcomas are an infrequent and heterogeneous group of neoplasia. Surgery with or without associated radiotherapy (RT) is the basic treatment for this type of tumour. To increase the therapeutic ratio (the index between cytotoxic effects in tumours and normal tissue complications with a certain dose of radiation), new advances are being investigated to increase local and distant control and to decrease the morbidity of the treatment. The aim of this review was to analyse the different strategies, based on technology and biology, which are being investigated to increase the therapeutic ratio of this disease


No disponible


Assuntos
Humanos , Sarcoma/radioterapia , Neoplasias de Tecidos Moles/radioterapia , Extremidades/patologia , Radioterapia de Intensidade Modulada/métodos , Braquiterapia , Antineoplásicos/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico
3.
Clin. transl. oncol. (Print) ; 20(2): 160-168, feb. 2018. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-170555

RESUMO

Purpose. To report a single-institutional experience with the use of magnetic resonance imaging (MRI)-guided radiotherapy for cancers of the head and neck. Materials and methods. Between October 2014 and October 2016, 18 patients with newly diagnosed cancers of the head and neck were prospectively enrolled on an institutional registry trial investigating the feasibility and efficacy of external-beam radiotherapy delivered using on-board MRI. All patients had biopsy-proven evidence of malignancy, measurable disease, and the ability to provide consent. None had previously received any treatment. Median dose was 70 Gy (range 54-70 Gy). MRI scans were obtained as part of an image-guided registration protocol for alignment prior to and during each treatment. Concurrent chemotherapy was administered to 14 patients (78%). Patient-reported outcomes were assessed using the University of Washington quality of life instrument. Results. Seventeen of 18 patients completed the planned intensity-modulated radiotherapy (IMRT) treatment of which 15 (83%) had a complete response and 2 (11%) had a partial response based on initial post-therapy positron emission tomography (PET) at 3 months. The 1-year estimates of progression-free survival, overall survival, and local-regional control were 95, 96, and 95%, respectively. There were no treatment-related fatalities. The incidence of grade 3+ acute toxicity was 44%. The proportion of patients rating their health-related quality of life as "very good" or "outstanding" at 6 months and 1 year after completion of radiation therapy was 60 and 70%, respectively. Conclusions. MRI-guided radiotherapy achieves clinical outcomes comparable to contemporary series reporting on IMRT for head and neck cancer (AU)


No disponible


Assuntos
Humanos , Neoplasias de Cabeça e Pescoço/radioterapia , Radioterapia Guiada por Imagem/métodos , Imagem por Ressonância Magnética , Radioterapia de Intensidade Modulada/métodos , Resultado do Tratamento , Tomografia por Emissão de Pósitrons/métodos , Satisfação do Paciente
4.
Clin. transl. oncol. (Print) ; 19(12): 1469-1477, dic. 2017. tab, graf
Artigo em Inglês | IBECS | ID: ibc-168909

RESUMO

Purpose. The aim of this study was to assess the feasibility and treatment outcome of intensity modulated radiation therapy with simultaneous integrated boost (SIB-IMRT) in locally advanced non-small cell lung cancer (NSCLC) patients. Materials and methods. A total of 64 NSCLC patients with stage IIB (3%), IIIA (36%), and IIIB (61%) were treated with concomitant (N = 47; 73%) or sequential (N = 9; 14%) chemotherapy between February 2009 and January 2014. Eight patients (13%) received RT alone. All patients received the same irradiation scheme using IMRT: prophylactic dose for mediastinum was 56 Gy at 1.65 Gy/fraction and SIB to macroscopic disease up to 68 Gy at 2 Gy/fraction. Results. The median follow-up was 16 months (range, 1-70 months). The overall survival rate for all patients was 79% after 1 year and 46% after 2 years. Disease-free survival (DFS) was 81 and 45% after 1 and 2 years, respectively, resulting in a median DFS of 16 months. Multivariate analysis showed a statistically significant association between stage IIIB patients and a higher risk of mortality (HR 2.11; P = 0.019). In addition, T4 stage associated with higher risk of recurrence (HR 2.23; P = 0.024) while concomitant chemoradiation was associated with lower risk of any recurrence (HR 0.34; P = 0.004) No patient experienced grade ≥3 esophagitis and only 6 cases (9%) had grade 3 pneumonitis. Only having a higher lung volume was associated with higher risk of pneumonitis in the multivariate analysis (HR 16.21; P = 0.022). Conclusion. This study in advanced NSCLC patients shows that SIB-IMRT is an effective technique with acceptable toxicity, also when combined with chemotherapy (AU)


No disponible


Assuntos
Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Testes de Toxicidade , Toxicidade Aguda/análise
5.
Clin. transl. oncol. (Print) ; 19(9): 1161-1167, sept. 2017. tab, graf
Artigo em Inglês | IBECS | ID: ibc-165219

RESUMO

Background/purpose. To evaluate the impact of intensity-modulated radiotherapy (IMRT) with intra-prostate fiducial markers image-guided radiotherapy (IGRT) on the incidence of late urinary toxicity compared to 3D conformal radiotherapy (3DCRT) for patients with prostate cancer (PC). Methods and materials. We selected 733 consecutive patients with localized PC treated with dose-escalation radiotherapy between 2001 and 2014. Eligibility criteria were radiation dose >72.0 Gy, no pelvic RT and minimum follow-up 24 months. 438 patients were treated with 3DCRT and 295 with IMRT. Acute and late urinary complications were assessed using the EORTC/RTOG and CTCAEs v3.0 definition. The Cox regression model was used to compare grade ≥2 urinary toxicity between both techniques. The median follow-up was 75 months (range 24-204). Results. The median isocenter radiation dose was 78.7 Gy for 3DCRT and 80.7 Gy for IMRT/IGRT (p < 0.001). The 5-year incidence of late grade ≥2 urinary toxicity was 6.4% for IMRT and 10.8% for 3DCRT [hazard ratio (HR) 0.575, p = 0.056]. The corresponding 5-year estimates of late grade ≥2 hematuria were 2% for IMRT and 5.3% for 3DCRT (HR 0.296, p = 0.024). On multivariate analysis, the antecedent of prior transurethral resection of the prostate was also a strong predictor of a higher risk of urinary complications (HR 2.464, p = 0.002) and of hematuria (HR 5.196, p < 0.001). Conclusion. Compared with 3DCRT, high-dose IMRT/IGRT is associated with a lower rate of late urinary complications in spite of higher radiation dose (AU)


No disponible


Assuntos
Humanos , Masculino , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/urina , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada , Radioterapia Guiada por Imagem/métodos , Medidas de Toxicidade , Ressecção Transuretral da Próstata , Análise Multivariada , Radioterapia/métodos
6.
Clin. transl. oncol. (Print) ; 19(4): 470-476, abr. 2017. tab, graf
Artigo em Inglês | IBECS | ID: ibc-160897

RESUMO

Purpose. Limited data have been published regarding the effect of adaptive radiotherapy (ART) on clinical outcome in patients with nasopharyngeal carcinoma (NPC). We compared the long-term outcomes in patients with locally advanced NPC treated by adaptive intensity-modulated radiotherapy (IMRT) replanning versus IMRT. Methods. 200 NPC patients with stage T3/T4 were included between October 2004 and November 2010. Patients in both treatment groups were matched using propensity score matching method at the ratio of 1:1. Clinical outcomes were analyzed with Kaplan-Meier method, log-rank test and Cox regression. Results. After matching, 132 patients (66 patients in each group) were included for analysis. The median follow-up for the IMRT replanning group was 70 months, while the IMRT group was 69 months. The 5-year local-regional recurrence-free survival (LRFS) rate was higher in IMRT replanning group (96.7 vs. 88.1 %, P = 0.022). No significant differences in distant metastasis-free survival (DMFS), progression-free survival (PFS) and overall survival (OS) were observed between the two groups. 21.2 % patients in IMRT replanning group and 28.8 % patients in IMRT group had distant metastasis. In multivariable analysis, IMRT replanning was identified as an independent prognostic factor for LRFS (hazard ratio 0.229; 95 % CI 0.062-0.854; P = 0.028), but not for DMFS, PFS and OS. Conclusions. IMRT replanning provides an improved LRFS for stage T3/T4 NPC patients compared with IMRT. Distant metastasis remains the main pattern of treatment failure. No significant advantage was observed in DMFS, PFS and OS when adaptive replanning was used (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Neoplasias Nasofaríngeas/radioterapia , Carcinoma/radioterapia , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada , Prognóstico , Radioterapia (Especialidade)/normas , Estimativa de Kaplan-Meier , Neoplasias Nasofaríngeas/tratamento farmacológico , Estudos de Coortes , Receptores dos Hormônios Tireóideos/uso terapêutico
7.
Clin. transl. oncol. (Print) ; 18(5): 469-479, mayo 2016. ilus, graf
Artigo em Inglês | IBECS | ID: ibc-151180

RESUMO

Purpose: Dose-volume histogram (DVH) has become an important tool for evaluation of radiation outcome as reflected from many clinical protocols. While dosimetric accuracy in treatment planning system (TPS) is well quantified, the variability in volume estimation is uncertain due to reconstruction algorithm that is investigated in this study. In addition, the impact of dose distribution and tumor control probability (TCP) were also investigated with CT slice thickness for IMRT planning. Materials and methods: A water phantom containing various objects with accurately known volume ranging from 1 to 100 cm3 was scanned with 1, 2, 3, 5, and 10 mm slice thickness. The CT data sets were sent to Eclipse TPS for contour delineation and volume estimation. The data were compared with known volume for the estimation of error in the volume of each structure. IMRT Plans were generated on phantom containing four objects with different slice thickness (1–5 mm) to calculate TCP. ICRU-83- recommended dose points such as D2%, D50%, D98%, as well as homogeneity and conformity index were also calculated. Results: The variability of volumes with CT slice thickness was significant especially for small volume structures. A maximum error of 92 % was noticed for 1 cm3 volume of object with 10 mm slice thickness, whereas it was *19 % for 1 mm slice thickness. For 2 and 3 cm3 objects, the maximum error of 99 % was noticed with 10 mm slice thickness and *60 % with 5 mm. The differences are smaller for larger volumes with a cutoff at about 20 cm3. The calculated volume of the objects is a function of reconstruction algorithm and slice thickness. The PTV mean dose and TCP decreased with increasing slice thickness. Maximum variation of *5 % was noticed in mean dose and *2 % in TCP with change in slice thickness from 1 to 5 mm. The relative decrease in target volume receiving 95 % of the prescribed dose is *5 % with change in slice thickness from 1 to 5 mm. The homogeneity index increases up to 163 % and conformity index decreases by 4 % between 1 and 5 mm slice thickness, producing highly inhomogeneous and least conformal treatment plan. Conclusions: Estimation of a volume is dependent on CT slice thickness and the contouring algorithm in a TPS. During commissioning of TPS and for all clinical protocols, evaluation of volume should be included to provide the limit of accuracy in DVH from TPS, especially for small objects. A smaller slice thickness provides superior dosimetry with improved TCP. Thus, the smallest possible slice thickness should be used for IMRT planning, especially when smaller structures are present (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada , Radiobiologia/instrumentação , Radiobiologia/métodos , Dosimetria/métodos , Protocolos Clínicos/normas , Neoplasias Encefálicas/radioterapia
8.
Med. oral patol. oral cir. bucal (Internet) ; 20(3): e273-e277, mayo 2015. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-139041

RESUMO

BACKGROUND: This study is conducted mainly to evaluate the changes in quality and quantity of oral epithelial cells during the course of IMRT.MATERIAL AND METHODS:30 Patients undergoing chemo-radiotherapy were followed through course of treatment. They were compared with a group of age- and sex-matched healthy individuals. The procedure involved WHO clinical scoring, collection of oral washings and preparation of buccal smears from both study group and control group. The changes occurred were recorded as a way of assessing the severity of oral mucositis. RESULTS: revealed a significant occurrence of oral mucositis in almost all patients during weekly follow up. There was a significant increase in percentage of viable buccal epithelial cells in study group when compared to normal controls (P<0.005) during and at the end of chemo-radiotherapy. CONCLUSIONS: quantification of oral mucositis can be done at cellular level by determining the oral mucosal cell viability and their maturation during IMRT (AU)


Assuntos
Humanos , Quimiorradioterapia/efeitos adversos , Estomatite/epidemiologia , Neoplasias de Cabeça e Pescoço/complicações , Sobrevivência Celular , Sobrevivência Celular/efeitos da radiação , Radioterapia de Intensidade Modulada/efeitos adversos , Técnicas In Vitro/métodos
9.
Clin. transl. oncol. (Print) ; 16(11): 1000-1005, nov. 2014.
Artigo em Inglês | IBECS | ID: ibc-128642

RESUMO

BACKGROUND: Brain metastases (BMs) represent an important cause of morbidity in patients with non-small-cell lung cancer (NSCLC) and are associated with a mean survival of <1 year. Thus, new regimens improving the outcome of these patients are urgently needed. We have evaluated the response to treatment, overall survival, disease progression, and adverse effects of a concomitant treatment with whole brain radiation therapy (WBRT) followed by intensity-modulated boosting RT (IMBRT) and temozolomide (TMZ) in patients with BMs from NSCLC. METHODS: A total of 32 patients with no more than four BMs were enrolled in this retrospective study. Patients received 30 Gy of WBRT in 15 fractions and followed by 20 Gy of IMBRT in 10 fractions with concomitant TMZ of 75 mg/m(2)/day orally during RT and continued TMZ therapy (150-200 mg/m(2)/day for 5 days every 28 days for an additional 2-6 cycles after RT). RESULTS: Three patients had a complete response, 9 patients had a partial response, while 15 patients had stable disease; therefore, the objective responses achieved 37.5 %. Median overall survival was 8.0 months and median time to progression was 5.5 months. Common treatment-related adverse effects (Grade ≤2) included nausea, vomiting, and asthenia. Grade 3 or worse hematologic toxicities were rare. No patient presented with gross neurocognitive dysfunction. CONCLUSION: WBRT followed by IMBRT combined with concomitant TMZ is well tolerated, yielding an encouraging objective response rate; however, overall survival improves slightly comparing with RTOG 9508 randomized trial (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Carcinoma Pulmonar de Células não Pequenas/terapia , Metástase Neoplásica , Neoplasias Encefálicas/radioterapia , Morbidade , Radioterapia de Intensidade Modulada
10.
Clin. transl. oncol. (Print) ; 16(2): 141-146, feb. 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127716

RESUMO

PURPOSE: To evaluate the impact of different machines on plan quality using both intensity modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) techniques. MATERIALS AND METHODS: Eight patients with squamous cell carcinoma of the oropharynx were selected at random. Plans were computed for IMRT and VMAT Smart Arc, using Pinnacle TPS for an Elekta (IMRT-E, VMAT-E) and Varian linac (IMRT-V, VMAT-V). A three-dose level prescription was used to deliver 70, 63 and 58.1 Gy to regions of macroscopic, microscopic high- and low-risk disease, respectively. All doses were given in 35 fractions. Comparisons were performed on dose-volume histogram data, monitor units (MU), and delivery time. RESULTS: VMAT-E plans resulted slightly MU efficient (-24 % p < 0.05) compared to VMAT-V while IMRT-V shortened delivery time (-19 % p < 0.05) compared to IMRT-E. All the delivery techniques resulted in equivalent target coverage in terms of D(98) % and D(2) %. For VMAT technique, a significant improvement of 7 % in homogeneity index (HI) for PTV58.1 was observed for Varian machine. A slight improvement in OARs sparing was observed with Elekta machine both for IMRT and VMAT techniques. CONCLUSION: Similar plan quality was observed for Elekta and Varian linacs, significant differences were observed in delivery efficiency, as MU number and delivery times, in favor of Elekta and Varian, respectively (AU)


No disponible


Assuntos
Humanos , Aceleradores de Partículas/normas , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/normas , Carcinoma de Células Escamosas/radioterapia , Desenho de Equipamento , Tratamentos com Preservação do Órgão , Órgãos em Risco , Neoplasias Orofaríngeas/radioterapia , Controle de Qualidade , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/normas
11.
Clin. transl. oncol. (Print) ; 16(2): 208-212, feb. 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127726

RESUMO

INTRODUCTION: To evaluate the delivery accuracy of dynamic (DMLC) and static (SMLC) intensity modulated radiation therapy (IMRT) techniques using portal dosimetry (PD) in Varian Eclipse Treatment Planning System. MATERIALS AND METHODS: Seven DMLC IMRT Head and Neck plans were retrospectively generated for the study using SMLC mode at 20, 10 and 5 levels of intensity (SMLC20, SMLC10, SMLC5). Dosimetric verifications performed by PD on a total of 107 fields were evaluated using the gamma index (maximum (γmax), average (γavg), percentage of points with (γ%) ≤ 1). The images were acquired at a source-detector distance of 100 cm at gantry zero degree and also at clinically planned gantry angles. RESULTS: For both modes, measurements are within acceptable criteria. (γ%) ≤ 1 improves by increasing SMLC levels (+3.4 % from SMLC5 to SMLC20, p < 0.001) and using DMLC (+3.9 % and +0.6 % compared to SMLC5 and SMLC20, respectively, p < 0.001). Also (γmax) parameter improves significantly by increasing SMLC levels (+22 % from SMLC5 to SMLC20) and using DMLC (+34 % and +16 % compared to SMLC5 and SMLC20, respectively). The effect of the gantry rotation influences the delivery accuracy by up to -7 % (p < 0.05). The effect of leaves travelling direction was almost negligible (1 %). CONCLUSIONS: A good agreement between calculated and measured fluences was obtained for DMLC and SMLC techniques at higher intensity levels; however, DMLC delivery ensures the best reproduction of computed fluence maps. The gantry rotation influences the delivery accuracy in particular for SMLC modes at lower intensity levels (AU)


No disponible


Assuntos
Humanos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco , Sensibilidade e Especificidade , Estudos Retrospectivos
12.
Clin. transl. oncol. (Print) ; 16(1): 69-76, ene. 2014. tab
Artigo em Inglês | IBECS | ID: ibc-127522

RESUMO

PURPOSE: To assess the heart and lung dosimetry results associated with accelerated partial breast irradiation intensity-modulated radiotherapy (APBI-IMRT) and whole breast field-in-field intensity-modulated radiotherapy (WBI-FIF-IMRT). METHODS: A total of 29 patients with early-stage breast cancer after lumpectomy were included in this study. APBI-IMRT and WBI-FIF-IMRT plans were generated for each patient. The dosimetric parameters of ipsilateral lung and heart in both plans were then compared with and without radiobiological correction. RESULTS: With and without radiobiological correction, the volume of ipsilateral lung showed a substantially lower radiation exposure in APBI-IMRT with moderate to high doses (P < 0.05) but non-significant increases in volume of ipsilateral lung in 2.5 Gy than WBI-FIF-IMRT (P > 0.905).There was no significant difference in volume of ipsilateral lung receiving 1, 2.5, and 5 Gy between APBI-IMRT and WBI (P > 0.05) in patients with medial tumor location, although APBI-IMRT exposed more lung to 2.5 and 5 Gy. APBI-IMRT significantly decreases the volume of heart receiving low to high doses in left-sided breast cancer (P < 0.05). CONCLUSION: APBI-IMRT can significantly spare the volume of heart and ipsilateral lung receiving moderate and high dose. Non-significant increases in volume of the ipsilateral lung exposed to low doses of radiation were observed for APBI-IMRT in comparison to WBI-FIF-IMRT, particularly in patients with medial tumor location. With the increasing interest in APBI-IMRT, our data may help clinicians individualize patient treatment decisions (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/radioterapia , Quimioterapia Combinada , Coração/efeitos da radiação , Pulmão/efeitos da radiação , Radioterapia , Radioterapia de Intensidade Modulada , Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Radiometria , Planejamento da Radioterapia Assistida por Computador
13.
Clin. transl. oncol. (Print) ; 16(1): 96-101, ene. 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127526

RESUMO

PURPOSE: The objective of this study is to evaluate the tolerability and outcome of craniospinal irradiation (CSI) with helical tomotherapy (HT) in the treatment of medulloblastoma. METHODS: We evaluated 19 consecutive patients with primary medulloblastoma who were treated with HT from 2007 through 2010. HT regimens to the neuroaxis included: 23.4 Gy at 1.8 Gy/fraction (N = 10), 36 Gy at 1.8 Gy/fraction (N = 7), and 39 Gy bid at 1.3 Gy/fraction (N = 2). The tumor bed received 54-60 Gy. Potential associations between patient, treatment, and toxicity factors and overall survival (OS) were assessed in univariate analyses using the Cox proportional hazards model. Spearman's rank correlation coefficient was used to correlate potential risk factors with the grade of acute toxicity. RESULTS: The median age at diagnosis was 5 years (range 2-14) and the median follow-up for alive patients (N = 14) 40 months (range 10-62). Two- and three-year overall survival was 75 and 68 %, respectively. The most common acute toxicity was hematological (79 %), being grade 2 and grade 3 in 4 (21 %) and 11 (58 %) cases, respectively. No grade ≥2 late toxicities were observed. Higher grades of acute body toxicity were found in older children (P = 0.004). Longer time between diagnosis and radiation therapy was correlated with shorter OS (P = 0.03). In addition, higher grades of acute thrombocytopenia were associated with shorter OS (P = 0.03). CONCLUSIONS: CSI delivered with HT for medulloblastoma is well tolerated with low rates of severe acute toxicity. Further research is necessary to assess late toxicity with a longer follow-up (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Radiação Cranioespinal/efeitos adversos , Meduloblastoma/radioterapia , Radioterapia de Intensidade Modulada/efeitos adversos , Resultado do Tratamento , Neoplasias Encefálicas/radioterapia , Radiação Cranioespinal/métodos
14.
Clin. transl. oncol. (Print) ; 15(3): 233-242, mar. 2013. tab, ^ilus
Artigo em Inglês | IBECS | ID: ibc-127083

RESUMO

PURPOSE: To determine retrospectively 2-3 year local and regional control (LRC), free-of-disease survival (FDS) and overall survival (OS), as well as summarized toxicities in a group of 31 advanced head-and-neck cancer patients, treated at our institution between 2004 and 2011 with definitive IMRT low-dose concomitant boost, the majority of them with concurrent chemotherapy based on cisplatin. The results are also shown in the sub-group of nasopharyngeal cancer patients (NPC: 15 cases). PATIENTS AND METHODS: Radiological basal and contrasted CT series, MR-CT or PET/CT fused images in the setup position with immobilization mask were registered in simulation therapy patients. Planed doses were: 70 Gy in primary tumor and positive nodes >1 cm; 63 Gy in high-risk areas of microscopic diseases +10 mm safety margin; and 56 Gy in low risk of diseases regional lymph nodes. Treatment was delivered using a Varian 2100 Clinac with sliding windows IMRT. Spinal cord doses were limited to a strict maximum of 45 Gy, and optimization aimed for mean doses in parotid glands below 26 Gy, especially in the contralateral parotid gland. Online DRR-portal X-ray comparison images were taken every day with a deviation module tolerance ≤3 mm. RESULTS: The mean follow-up since IMRT was 34 months (interval: 8-89; median 31 months). Median follow-up in living patients was 22 months. The 2-year rate for global LRC was 64 %, for FDS 61 % and OS 77 %. For the NPC group after 2 years, LRC was 73 %, FDS 73 % and OS 93 %. The 3-year rates were similar. Seven patients died as a consequence of local and/or regional progression (mean time 10 months). Relapses were observed in eight patients (26 %), but only seven could be confirmed by biopsy (22.6 %; mean time to relapse: 8.6 months). Global acute mucositis was 61 % and chronic mucositis was shown in six cases which developed xerostomia (19 %) in the first control after IMRT, but 1 year later it was reduced to only four patients, two Grade 2 and two Grade 1. CONCLUSIONS: No excessive, unwarranted toxicities were observed using concomitant low doses boost in IMRT. High rates of compliance to concurrent chemotherapy were achieved. Late xerostomia associated with this regime decreased 1 year after conclusion of treatment. The implementation of IMRT requires advances in imaging for better tumor delineation; otherwise the physician loses the advantage of dose modulation or faces a risk of geographical miss (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/mortalidade , Quimiorradioterapia , Cisplatino/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/mortalidade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/mortalidade , Estadiamento de Neoplasias , Estudos Retrospectivos
15.
Clin. transl. oncol. (Print) ; 14(6): 465-470, jun. 2012.
Artigo em Inglês | IBECS | ID: ibc-126816

RESUMO

OBJECTIVE: To investigate the clinical effects and adverse effects of weekly recombinant human endostatin (RHES) as a hypoxic tumour cell radiosensitiser combined with radiotherapy in the treatment of non-small-cell lung cancer (NSCLC). METHODS: Fifty hypoxia-positive cases of pathology-diagnosed NSCLC (stage I-III) were randomly divided into a RHES+radiotherapy group (25 cases) and a radiotherapy alone group (25 cases). Intensity-modulated radiotherapy (IMRT) with a total dose of 60 Gy/30F/6W was adopted in the two groups. Target area included primary foci and metastatic lymph nodes. In the RHES+radiotherapy group, RHES (15 mg/day) was intravenously given during the first week. The therapeutic effects and adverse reactions were evaluated after treatment. RESULTS: In the RHES+radiotherapy and radiotherapy alone groups, the total effective rates (CR+PR) were 80% and 44% (χ(2)=6.87, p=0.009), respectively. The one-year and two-year local control rates were (78.9±8.4)% and (68.1±7.8)% (p=0.027), and (63.6±7.2)% and (43.4±5.7)% (p=0.022), respectively. The median progression-free survival was (21.1±0.97) and (16.5±0.95) months, respectively. The one-year and two-year overall survival rates were (83.3±7.2)% and (76.6±9.3)% (p=0.247), and (46.3±2.4)% and (37.6±9.1)% (p=0.218), respectively. CONCLUSION: RHES combined with radiotherapy within the first week has better short-term therapeutic effects and local control rate, and no severe adverse reactions in treatment of NSCLC. However, it failed to significantly improve the one-year and two-year overall survival rates (AU)


Assuntos
Idoso , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas , Endostatinas/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Radiossensibilizantes/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Hipóxia Celular , Terapia Combinada , Intervalo Livre de Doença , Esquema de Medicação , Endostatinas/uso terapêutico , Neoplasias Pulmonares/patologia , Radiossensibilizantes/uso terapêutico , Radioterapia de Intensidade Modulada , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico
16.
Clin. transl. oncol. (Print) ; 13(4): 268-274, abr. 2011. tab
Artigo em Inglês | IBECS | ID: ibc-124434

RESUMO

PURPOSE: To describe early clinical results of tomotherapy treatment in patients with breast cancer and complex treatment volumes. METHODS AND MATERIALS: Ten patients were treated with tomotherapy between January 2009 and March 2010. Treatment planning objectives were to cover at least 95% of the planning target volume with the 95% isodose; to have a minimum dose of 90% and a maximum dose of 105%. All treatments included daily CT/megavoltage image guidance. Acute toxicity was recorded weekly. RESULTS: Six patients were treated because constraints were not accomplished for heart, lung or contralateral breast in a previous three-dimensional conformal plan; two for preexisting cardiac or pulmonary disease, and two more for bilateral breast irradiation. Treatment volumes included the whole breast in the majority of patients, as well as the supraclavicular and the internal mammary chain nodes when indicated. Most patients were older than 50 years, and had an early breast cancer, with positive oestrogen receptors, negative HER2 expression and a poorly differentiated, infiltrating ductal carcinoma. The majority of patients had received neoadjuvant chemotherapy associated to breast-conserving surgery and adjuvant hormonotherapy. Median homogeneity index was 1.09; median coverage index was 0.81. Median V20Gy and V10Gy for ipsilateral lung was 20% and 37.1% respectively. Median V25 and V35 for heart was 15% and 4% respectively. Median dose for contralateral breast was 7 Gy. Skin acute toxicity was grade 1 in 41.7% and grade 2 in 58.3%. CONCLUSION: Tomotherapy is a technique capable of delivering a well tolerated treatment with high homogeneity and coverage indexes and high capabilities for sparing the organs at risk in patients with anatomically complex breast cancer, bilateral breast cancer, indication for internal mammary chain node irradiation, cardiac toxicity derived from chemotherapy, or preexisting cardiac or pulmonary disease. Further studies are required to evaluate local control and late toxicity (AU)


Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Neoplasias da Mama/radioterapia , Dosagem Radioterapêutica/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/normas , Planejamento da Radioterapia Assistida por Computador , Antineoplásicos/uso terapêutico , Terapia Combinada/métodos , Terapia Combinada , Terapia Neoadjuvante/métodos , Terapia Neoadjuvante , Radioterapia de Intensidade Modulada/métodos , Radioterapia de Intensidade Modulada , Estudos Retrospectivos
17.
An. sist. sanit. Navar ; 32(supl.2): 5-12, ago. 2009.
Artigo em Espanhol | IBECS | ID: ibc-73326

RESUMO

En los últimos veinte años el extraordinario augede la informática ha permitido desarrollos tecnológicostrascendentales al servicio de la precisión en los tratamientosradioterápicos: en la obtención de imágenes entres dimensiones, en los sistemas de planificación y enlas unidades de irradiación. De manera que en menosde dos décadas se ha pasado de la radioterapia en dosdimensiones (RT 2D) a la radioterapia conformada en3D (RTC3D) y a la modulación de la intensidad de laradiación para la máxima conformación (IMRT).La alta precisión en la entrega de la radiación ajustala dosis prescrita al volumen blanco preservandomejor los tejidos sanos adyacentes. De manera que sepuede aspirar a mejorar el índice terapéutico en dossentidos, bien disminuyendo la toxicidad tardía cuandoesta es un problema de suficiente entidad o escalandola dosis en el volumen blanco para aumentar el controltumoral sin provocar más la toxicidad.Un último componente en llegar a la radioterapiadel presente resulta de importancia capital: la imagenguiada, que permite dirigir los haces de irradiaciónadaptándolos a los posibles cambios de posición delvolumen blanco antes o durante el tratamiento(AU)


In the last twenty years the extraordinary rise ofinformation technology has made possible key technologicaldevelopments at the service of precision in radiotherapytreatments: in obtaining three-dimensionalimages, in systems planning and in radiation units.Thus in less than two decades there progress has beenmade from radiotherapy in two dimensions (RT 2D) to3D conformal radiotherapy (3DCRT) and to modulationof intensity modulated radiotherapy for maximum conformation(IMRT).High precision in radiation delivery adjusts theprescribed dosage to the white volume, better preservingthe adjacent healthy tissue. It is thus possible toaspire to improving the therapeutic index in two respects,either reducing late toxicity when this is a problemof sufficient scale, or scaling the dosage in thewhite volume in order to increase tumour control withoutprovoking further toxicity.A final component in reaching the present state ofradiotherapy is of capital importance: the guided imagewhich makes it possible to direct the beams of radiation,adapting them to the possible changes of positionof the white volume before or during treatment(AU)


Assuntos
Humanos , Radioterapia/tendências , Braquiterapia/métodos , Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos
18.
An. sist. sanit. Navar ; 32(supl.2): 13-20, ago. 2009. ilus
Artigo em Espanhol | IBECS | ID: ibc-73327

RESUMO

Tanto los sistemas de planificación como la formade administración de los tratamientos radioterápicoshan cambiado radicalmente desde la introducción dela planificación tridimensional 3D. En la actualidad laplanificación de los tratamientos basada en imágenesde tomografía axial computarizada (TAC) es el estándarde los servicios de radioterapia. En los últimos años losaceleradores lineales para uso médico, han incorporandotecnología capaz de administrar haces de tratamientode intensidad modulada, IMRT. Con esta modalidadse generan distribuciones de dosis altamente conformadasque se ajustan a la forma tridimensional del volumenblanco, proporcionando una cobertura adecuaday una menor dosis a los órganos de riesgo cercanos.El uso de la IMRT rápidamente se está extendiendoentre los centros de radioterapia de todo el mundo.Este creciente uso de la IMRT ha focalizado la atenciónen la necesidad de un mayor control de las incertidumbresgeométricas en el posicionamiento del paciente yun control de los movimientos internos, por ello se hanincorporado a los equipos de tratamiento sistemas deimagen tanto planar como volumétrica, que posibilitanuna radioterapia guiada por la imagen, IGRT. En este trabajose presenta una breve descripción de los últimosavances incorporados a la planificación y administracióndel tratamiento radioterápico(AU)


Both the planning systems and the form of administeringradiotherapy have changed radically since theintroduction of 3D planning. At present treatment planningbased on computerised axial tomography (CAT)images is standard practice in radiotherapy services.In recent years lineal accelerators for medical use haveincorporated technology capable of administering intensitymodulated radiation beams (IMRT). With thismode distributions of conformed doses are generatedthat adjust to the three dimensional form of the whitevolume, providing appropriate coverage and a lowerdose to nearby risk organs.The use of IMRT is rapidly spreading amongst radiotherapycentres throughout the world. This growinguse of IMRT has focused attention on the need forgreater control of the geometric uncertainties in positioningthe patient and control of internal movements.To this end, both flat and volumetric image systemshave been incorporated into the treatment equipment,making image-guided radiotherapy (IGRT) possible.This article offers a brief description of the latest advancesincluded in the planning and administration ofradiotherapy treatment(AU)


Assuntos
Humanos , Radioterapia/instrumentação , Aceleradores de Partículas , Radiocirurgia/métodos , Radioterapia/métodos , Radioterapia Assistida por Computador/instrumentação , Radioterapia Conformacional/instrumentação , Radioterapia de Intensidade Modulada/instrumentação
19.
An. sist. sanit. Navar ; 32(supl.2): 21-31, ago. 2009. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-73328

RESUMO

La radioterapia de intensidad modulada (IMRT)representa una de las mayores innovaciones técnicasde la moderna radioterapia. Su capacidad de conseguirtratamientos con la dosis altamente conformada al áreade irradiación permite tratar volúmenes próximos aórganos de riesgo con gran seguridad. Estas característicasla convierten en una técnica ideal para estudios,bien de disminución de toxicidad en órganos de riesgo,bien de intensificación de dosis para mejorar el controlde la enfermedad. La primera parte de este artículo tratarásobre qué se entiende por IMRT y sus peculiarescaracterísticas dosimétricas, así como de los tipos deIMRT; en la segunda parte se tratará la evidencia clínicaen algunas de las localizaciones más investigadas comoson tumores de cabeza y cuello, próstata y mama(AU)


Intensity-modulated radiation therapy (IMRT)represents one of the greatest technical innovationsin modern radiotherapy. Its capacity of achievingtreatments with the dose conforming largely to the irradiatedarea makes it possible to treat volumes close toorgans at risk with great safety These characteristicsmake it an ideal technique for studies, whether for reducingtoxicity in organs at risk, or for intensifying dosagesto improve the control of the disease. The first partof the article considers what is understood by IMRTand its peculiar dosimetric characteristics, as well thetypes of IMRT; the second part deals with the clinicalevidence in some localisations such as tumours of thehead and neck, prostate and breast(AU)


Assuntos
Humanos , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Mama/radioterapia , Neoplasias da Próstata/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Fatores de Risco
20.
Clin. transl. oncol. (Print) ; 11(7): 437-445, jul. 2009. tab
Artigo em Inglês | IBECS | ID: ibc-123656

RESUMO

Over the last 10 years the radiobiology of prostate cancer has been studied both in experimental research and in clinical trials of hypofractionated radiotherapy. Unlike most cancers, the alpha/beta ratio of the prostatic carcinoma is probably lower than that of the healthy organs around the gland, although there is no agreement as to how low this alpha/beta really is. This peculiarity implies that, theoretically, a hypofractionated schedule would increase the therapeutic gain of radiotherapy. Until now, following four published randomised trials, hypofractionated radiotherapy has shown results in terms of acute and chronic toxicity and tumour control similar to those obtained with conventionally fractionated radiotherapy. However, these studies are not conclusive. The two studies that involved significant followup used 2D technique and delivered low total equivalent dose. On the other hand, the two most recent trials, which administered total equivalent doses = or >78 Gy with modern techniques (IMRT, IGRT), involved the disadvantage of small samples and a short follow-up period. The results of ongoing randomised trials are necessary to confirm the advantages of hypofractionation over normofractionated radiotherapy. The impact of hypofractionated radiotherapy on the patient's health-related quality of life, and on transports and health care costs, should also be investigated (AU)


Assuntos
Humanos , Masculino , Ensaios Clínicos como Assunto/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada , Doses de Radiação , Resultado do Tratamento
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