Terahertz spectroscopy for the study of paraffin-embedded gastric cancer samples

• Gastric cancer detection.
• Paraffin-embedded samples.
• Cancer affected tissue regions, low transmittance.
• High absorption coefficient and refractive index for affected tissue.
• Dehydration of bio-tissues lead t low contrast.

Terahertz (THz) spectroscopy constitute promising technique for biomedical applications as a complementary and powerful tool for diseases screening specially for early cancer diagnostic. The THz radiation is not harmful to biological tissues. As increased blood supply in cancer-affected tissues and consequent local increase in tissue water content makes THz technology a potentially attractive. In the present work, samples of healthy and adenocarcinoma-affected gastric tissue were analyzed using transmission time-domain THz spectroscopy (THz-TDS). The work shows the capability of the technique to distinguish between normal and cancerous regions in dried and paraffin-embedded samples. Plots of absorption coefficient α and refractive index n of normal and cancer affected tissues, are presented and the conditions for discrimination between normal and affected tissues are discussed.