RESUMEN
AIMS: An increase in the demand of a new generation of radiotherapy planning systems based on learning approaches has been reported. At this stage, the new approach is able to improve the planning speed while saving a reasonable level of plan quality, compared with available planning systems. We believe that new achievements, such as deep-learning models, will be able to review the issue from a different point of view. MATERIALS AND METHODS: The data of 120 breast cancer patients were used to train and test the three-dimensional U-Res-Net model. The network input was computed tomography images and patients' contouring, while the patients' dose distribution was addressed as the output of the model proposed. The predicted dose distributions, created by the model for 10 test patients, were then compared with corresponding dose distributions calculated by a reliable treatment planning system. In particular, the dice similarity coefficients for different isodose volumes, dose difference and mean absolute errors (MAE) for all voxels inside the body, Dmean, D98%, D50%, D2%, V95% for planning target volume and organs at risk were calculated and were statistically analysed with the paired-samples t-test. RESULTS: The average dose difference for all patients and voxels in body was 0.60 ± 2.81%. The MAE varied from 3.85 ± 6.65% to 8.06 ± 10.00%. The average MAE for test cases was 5.71 ± 1.19%. The average dice similarity coefficients for isodose volumes was 0.91 ± 0.03. The three-dimensional gamma passing rates with 3 mm/3% criteria varied from 78.99% to 97.58% for planning target volume and organs at risk, respectively. CONCLUSIONS: The investigation showed that a deep-learning model can be applied to predict the three-dimensional dose distribution with optimal accuracy and precision for patients with left breast cancer. As further study, the model can be extended to predict dose distribution in other cancers.
Asunto(s)
Neoplasias de la Mama , Aprendizaje Profundo , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Humanos , Femenino , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/radioterapia , Radioterapia Conformacional/métodosAsunto(s)
Neoplasias de la Mama/genética , Cromosomas Humanos Par 20 , Amplificación de Genes , Polimorfismo Genético , Repeticiones de Trinucleótidos , Alelos , Biomarcadores de Tumor , Femenino , Frecuencia de los Genes , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la PolimerasaRESUMEN
Immunohistochemistry was used to assess the distribution of protein tyrosine kinases in Alzheimer's disease (AD) pathology. One of these, fyn, exhibited an interesting pattern of immunoreactivity. Low levels of immunoreactivity were apparent in neurons from both normal and AD brain. However a subset of neurons in AD brain exhibited intense fyn immunoreactivity. Double label immunohistochemistry revealed that fyn-positive neurons were also positive for abnormally phosphorylated microtubule-associated protein, tau. Proline-directed kinases, whose activity is regulated by phosphorylation on tyrosine, may be responsible for abnormal tau phosphorylation. These results identify fyn as a candidate kinase for regulating putative proline-directed kinases involved in abnormal tau phosphorylation.