Potential of higher resolution synchrotron radiation imaging using crystal analyzer-based phase contrast X-ray techniques for differential diagnosis of human lung cancer

초록

Background: Synchrotron radiation imaging techniques showed higher microscopic resolution for visualizing biological soft tissues compared with conventional absorption-based tomography. We examined microstructural morphology of human lung cancer using synchrotron X-ray Dark-field Imaging (XDFI) method employing a precisely designed Laue angle analyzer for investigating potential clinical implication. Methods: Three-dimensional tomographic images of four histological subtypes of human lung cancer were obtained using X-ray Dark-field Imaging (XDFI) optics conducted at beamline BL-14B of the Photon Factory (PF), in Tsukuba, Japan. The synchrotron light source was generated from a 5-Tesla superconducting vertical wiggler installed in the 2.5-GeV storage ring with a energy of 19.8 keV. The specimens used for this study were obtained from surgically excised human lung cancers with written informed consent. For synchrotron radiation (SR) imaging, selected samples were embedded in 1% agarose gel and transported to beamline BL14B at the Photon Factory, KEK, Tsukuba, Japan. Three-dimensional reconstructions were generated using Amira-Avizo (v2020.3) with GPU-based rendering. Following imaging, specimens were paraffin-embedded, sectioned, H&E stained, and reviewed by a board-certified pathologist. SR-XDFI findings were compared with histopathology to validate structural correlations. Results: Synchrotron-based phase-contrast tomography clearly visualized normal distal lung microstructures and distinguished them from cancerous lesions. Transitional zones between malignant and normal tissues were identifiable in all samples, showing subtype-specific patterns. In areas adjacent to tumors, alveolar structures and related vasculature were preserved, serving as internal references. Conclusions: Synchrotron-based XDFI tomography provides non-destructive, high-resolution volumetric imaging of lung cancer tissues. Its capacity to distinguish subtle microstructural differences among tumor subtypes suggests strong potential for clinical applications in early diagnosis, subtype differentiation, and image-guided pathology correlation.