Evaluation of cancer tissue morphology via THz spectroscopic imaging: Human lung and small intestine malignancies

Abstract We investigate the potential of terahertz spectroscopic imaging for assessment of malignant tissues in human lung and small intestine using a reflection-mode time-domain spectroscopy system spanning the 60 GHz–2 THz band. These two tissue groups are among the few that can be reached via an endoscopic sensor, thus potentially allowing for in-situ assessment of suspected tumors. As an initial study toward this goal, we characterized formalin-fixed and paraffin-embedded tissue blocks using a commercially-available reflection-mode time domain spectroscopy system. We verify that the measured THz responses of these tissue groups reveal key differences in their morphology, material density, and electrical properties. The spectroscopic characteristics in the THz band are contrasted with the histopathologic assessment of hematoxylin and eosin stained tissue slices to demonstrate the potential of THz spectroscopy for evaluating lung and small intestine malignancies. For both types of organ tissues, it is demonstrated that the THz images provide key discriminatory information such as tissue morphology, cancer margin, and necrotic areas in the tumor.