Synchrotron tomographic images from human lung adenocarcinoma: Three-dimensional reconstruction and histologic correlations.

High-resolution tomographic images using synchrotron X-rays are expected to provide detailed reflection of microstructures, thereby allowing for the examination of histologic structures without destruction of the specimen. This study aims to evaluate the synchrotron tomographic images of mixed ground-glass opacity excised on 5-mm sections in comparison to pathologic examination. The Institutional Review Board of our institute approved this retrospective study, and written informed consent was obtained from each patient whose lung tissue would be used. Obtained lung cancer specimens were brought to the multiple Wiggler 6C beam line at the Pohang Light Source (PLS-II) in Korea, and phase contrast X-ray images were obtained in November 2016. The X-ray emanated from a bending magnet of the electron storage ring with electron energy of 3 GeV, and a typical beam current was 320 mA. Reconstructed tomographic images were compared with images from histologic slides obtained from the same samples. Pulmonary microstructures including terminal bronchioles, alveolar sacs, and vasculature were identified with phase contrast X-ray images. Images from normal lung tissue and mixed ground-glass opacity were clearly distinguishable. Hyperplasia of the interalveolar septum and dysplasia of microstructure were clearly identified. The imaging findings correlated well with hematoxylin-eosin stained specimens. Tomographic images using synchrotron radiation have the potential for clinical applications. With refinement, this technique may become a diagnostic tool for detection of lung cancer.