M.K. Khodzitsky1

1 Limited Liability Company «Terahertz Photonics» (St. Petersburg, Russia)
1 khodzitskiy@yandex.ru

Currently, oncological diseases are a serious problem in medicine, requiring the development of effective diagnostic and treatment methods. Stomach cancer is the fifth most common and the third most lethal cancer among oncological diseases. The main method of treating stomach cancer is surgical resection, the success of which depends on the scope of the intervention. It is important to remove the tumor with minimal damage to the stomach, since increasing the scope of the operation reduces the life expectancy of patients. The difficulty of diagnosing stomach cancer is associated with the lack of clear boundaries of the cancerous tissue. To determine the optimal volume of resection, a high-quality surgical analysis and clarification of the boundaries of the affected area of ​​the stomach are required. This requires effective methods for differentiating healthy and cancerous stomach tissue.

The aim of the study is to develop a method for intraoperative diagnostics of human gastric cancer based on terahertz (THz) dielectric spectroscopy using terahertz time-domain spectroscopy in reflection mode,

It was shown that using the dispersion of the real part of the permittivity and relaxation coefficients according to the Debye model (the dielectric permittivity at the high-frequency limit ε∞, the coefficients ε1 and ε2, the relaxation times τ1, and τ2)), it is possible to distinguish healthy and cancerous gastric tissue according to 6 criteria.

The proposed method allows diagnosing malignant tumors of the stomach at early stages due to a significant difference in the optical properties of cancer and healthy tissues in the THz frequency range and strong absorption of THz radiation by hydroxyl groups actively accumulating in malignant tumors. THz radiation is non-ionizing, which allows it to be used for diagnostics and visualization of the disease without harm to health. Thus, THz dielectric spectroscopy is an innovative and relevant method for diagnosing gastric cancer and can potentially become a new "gold standard" of intraoperative diagnostics.

Khodzitsky M.K. Terahertz dielectric spectroscopy of gastric biotissues for intraoperative cancer diagnostics. Biomedicine Radioen­gineering. 2025. V. 28. № 5. P. 180–186. DOI: https:// doi.org/10.18127/ j15604136-202505-35 (In Russian)

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