RESUMO
Radiogenomics designates a scientific field that addresses possible associations between genetic germline alterations and normal tissue toxicity after radiotherapy. The ultimate aim of this research is to establish a gene-based predictive test for normal tissue radiosensitivity. During the last 5 years, substantial progress has been achieved in this field. Several compelling associations for SNPs have been demonstrated in large candidate gene studies as well as genome wide association studies. These findings shed new light on radiobiology and expand our understanding of the processes that lead to side effects after radiotherapy. Despite this, certain fundamental challenges still relate to genomic approaches. Based on the latest insights into complex trait genetics and molecular genetics, we provide an analysis of these challenges and propose putative strategies to further advance the field. These strategies include 'big data approaches' and collaborative research within international consortia. Furthermore, research that combines the study of radiation-induced gene expression and genome-wide SNP genotype may discover genetic alterations that regulate the biological response to ionizing radiation. Thus, such integrative approaches may lead to genetic alterations that affect risk of normal tissue toxicity.
Assuntos
Genômica/métodos , Neoplasias/radioterapia , Polimorfismo de Nucleotídeo Único , Medicina de Precisão/métodos , Lesões por Radiação/genética , Radioterapia (Especialidade)/métodos , Tolerância a Radiação/genética , Mineração de Dados , Bases de Dados Genéticas , Difusão de Inovações , Previsões , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Genômica/história , Genômica/tendências , História do Século XX , História do Século XXI , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Medicina de Precisão/história , Medicina de Precisão/tendências , Locos de Características Quantitativas , Lesões por Radiação/metabolismo , Lesões por Radiação/prevenção & controle , Radioterapia (Especialidade)/história , Radioterapia (Especialidade)/tendências , Radioterapia/efeitos adversos , Medição de Risco , Fatores de Risco , Fator de Crescimento Transformador beta1/genéticaRESUMO
PURPOSE: Due to the often quite extended treatment fields in cervical cancer radiotherapy, uncorrected rotational set-up errors result in a potential risk of target miss. This study reports on the residual rotational set-up error after using daily cone beam computed tomography (CBCT) to position cervical cancer patients for radiotherapy treatment. METHODS AND MATERIALS: Twenty-five patients with locally advanced cervical cancer had daily CBCT scans (650 CBCTs in total) prior to treatment delivery. We retrospectively analyzed the translational shifts made in the clinic prior to each treatment fraction as well as the residual rotational errors remaining after translational correction. RESULTS: The CBCT-guided couch movement resulted in a mean translational 3D vector correction of 7.4 mm. Residual rotational error resulted in a target shift exceeding 5 mm in 57 of the 650 treatment fractions. Three patients alone accounted for 30 of these fractions. Nine patients had no shifts exceeding 5 mm and 13 patients had 5 or less treatment fractions with such shifts. CONCLUSION: Twenty-two of the 25 patients have none or few treatment fractions with target shifts larger than 5mm due to residual rotational error. However, three patients display a significant number of shifts suggesting a more systematic set-up error.