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A partir de la aproximación de electrón libre dentro de un semiconductor, se realizó análisis numérico del espectro energético y la densidad de probabilidad electrónica de un electrón dentro de un nanohilo hexagonal con estructura núcleo-corteza. En el análisis se consideró el efecto de aplicar un campo magnético en la dirección de crecimiento del nanohilo y se resolvió numéricamente la ecuación de Schrödinger para el electrón localizado en el plano transversal de la estructura en presencia del campo externo; los cálculos se realizaron por medio de elementos finitos implementados con COMSOL Multiphysics®. Los resultados obtenidos permitieron identificar capas energéticas, compuestas, cada una, de seis niveles. Estas capas se atribuyen a la geometría hexagonal conformada por seis pozos de potencial creados debido al abrupto cambio de dirección de los bordes de la estructura. Adicionalmente, se observaron las oscilaciones Aharonov-Bohm del sistema para una estructura con grosor significativo de la capa.

BackgroundParenchymal analysis has shown promising performance for the assessment of breast cancer risk through the characterization of the texture features of mammography images. However, the working principles behind this practice are yet not well understood. Field cancerization is a phenomenon associated with genetic and epigenetic alterations in large volumes of cells, putting them on a path of malignancy before the appearance of recognizable cancer signs. Evidence suggests that it can induce changes in the biochemical and optical properties of the tissue.PurposeThe aim of this work was to study whether the extended genetic mutations and epigenetic changes due to field cancerization, and the impact they have on the biochemistry of breast tissues are detectable in the radiological patterns of mammography images.MethodsAn in silico experiment was designed, which implied the development of a field cancerization model to modify the optical tissue properties of a cohort of 60 voxelized virtual breast phantoms. Mammography images from these phantoms were generated and compared with images obtained from their non‐modified counterparts, that is, without field cancerization. We extracted 33 texture features from the breast area to quantitatively assess the impact of the field cancerization model. We analyzed the similarity and statistical equivalence of texture features with and without field cancerization using the t‐test, Wilcoxon sign rank test and Kolmogorov‐Smirnov test, and performed a discrimination test using multinomial logistic regression analysis with lasso regularization.ResultsWith modifications of the optical tissue properties on 3.9% of the breast volume, some texture features started to fail to show equivalence (p < 0.05). At 7.9% volume modification, a high percent of texture features showed statistically significant differences (p < 0.05) and non‐equivalence. At this level, multinomial logistic regression analysis of texture features showed a statistically significant performance in the discrimination of mammograms from breasts with and without field cancerization (AUC = 0.89, 95% CI: 0.75–1.00).ConclusionsThese results support the idea that field cancerization is a feasible underlying working principle behind the distinctive performance of parenchymal analysis in breast cancer risk assessment.

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