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2.
Rep Pract Oncol Radiother ; 26(2): 226-236, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211773

RESUMO

BACKGROUND: The aim of the study was to evaluate the feasibility and safety of stereotactic body radiotherapy (SBRT) for the treatment of hepatocellular carcinoma in Brazil. SBRT is an evolving treatment in HCC patients not candidates to other local therapies. Its adoption in clinical practice has been heterogeneous, with lack of data on its generalizability in the Brazilian population. MATERIALS AND METHODS: We conducted a prospective pilot study involving HCC patients after failure or ineligibility for transarterial chemoembolization. Patients received SBRT 30 to 50 Gy in 5 fractions using an isotoxic prescription approach. This study is registered at clinicaltrials.gov NCT02221778. RESULTS: From Nov 2014 through Aug 2019, 26 patients received SBRT with 40 Gy median dose. Underlying liver disease was hepatitis C, hepatitis B and alcohol-related in, respectively, 50%, 23% and 19% of patients. Median lesion size was 3.8 cm (range, 1.5-10 cm), and 46% had multiple lesions. Thirty-two percent had tumor vascular thrombosis; median pretreatment alpha-fetoprotein (AFP) was 171.7 ng/mL (range, 4.2-5,494 ng/mL). 1y-local progression-free survival (PFS) was 86% (95% CI: 61% to 95%), with higher local control in doses ≥ 45Gy (p = 0.037; HR = 0.12). 1y-liver PFS, distant PFS and OS were, respectively, 52%, 77% and 79%. Objective response was seen in 89% of patients, with 3 months post-SBRT median AFP of 12 ng/mL (2.4-637 ng/mL). There were no grade 3 or 4 clinical toxicities. Grade 3 or 4 laboratory toxicities occurred in 27% of patients. CONCLUSION: SBRT is feasible and safe in patients unresponsive or ineligible for TACE in Brazil. Our study suggests doses ≥ 45 Gy yields better local control.

5.
Radiat Oncol ; 11(1): 116, 2016 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-27604995

RESUMO

BACKGROUND: Radiotherapy (RT) is frequently used in the treatment of head and neck cancer, but different side-effects are frequently reported, including a higher frequency of radiation-related caries, what may be consequence of direct radiation to dental tissue. The intensity-modulated radiotherapy (IMRT) was developed to improve tumor control and decrease patient's morbidity by delivering radiation beams only to tumor shapes and sparing normal tissue. However, teeth are usually not included in IMRT plannings and the real efficacy of IMRT in the dental context has not been addressed. Therefore, the aim of this study is to assess whether IMRT delivers lower radiation doses to dental structures than conformal 3D radiotherapy (3DRT). MATERIAL AND METHODS: Radiation dose delivery to dental structures of 80 patients treated for head and neck cancers (oral cavity, tongue, nasopharynx and oropharynx) with IMRT (40 patients) and 3DRT (40 patients) were assessed by individually contouring tooth crowns on patients' treatment plans. Clinicopathological data were retrieved from patients' medical files. RESULTS: The average dose of radiation to teeth delivered by IMRT was significantly lower than with 3DRT (p = 0.007); however, only patients affected by nasopharynx and oral cavity cancers demonstrated significantly lower doses with IMRT (p = 0.012 and p = 0.011, respectively). Molars received more radiation with both 3DRT and IMRT, but the latter delivered significantly lower radiation in this group of teeth (p < 0.001), whereas no significant difference was found for the other dental groups. Maxillary teeth received lower doses than mandibular teeth, but only IMRT delivered significantly lower doses (p = 0.011 and p = 0.003). Ipsilateral teeth received higher doses than contralateral teeth with both techniques and IMRT delivered significantly lower radiation than 3DRT for contralateral dental structures (p < 0.001). CONCLUSION: IMRT delivered lower radiation doses to teeth than 3DRT, but only for some groups of patients and teeth, suggesting that this decrease was more likely due to the protection of other high risk organs, and was not enough to remove teeth from the zone of high risk for radiogenic disturbance (>30Gy).


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Dente/efeitos da radiação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias de Cabeça e Pescoço/complicações , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Radiometria , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos , Adulto Jovem
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