The open-ended coaxial line method for colorectal cancer detection and depth evaluation of tumor invasion / 实用医学杂志

ABSTRACT

Objective To confirm whether the open-ended coaxial line is effective in detection of the differences in dielectric properties between colorectal cancer tissues and surrounding normal tissues and evaluation of the depth of tumor invasion. Methods The open-ended coaxial line system at frequencies ranging from 50 to 500 MHz in 98 freshly excised colorectal cancerous specimens obtained from the operating theatre of Zhujiang Hospital, was used to detect both the relative permittivity and conductivity on the serosal surface of the carcinoma nidus, the mucosa of the carcinoma nidus, and the mucosa of the surgical resection margin. Pathological examinations were conducted on each specimen after surgery. Results The values for relative permittivity and conductivity of the colorectal cancerous mucosa were significantly higher than those of the normal mucosa (P < 0.01). For the tumor which had invaded or penetrated the serosa (stage ≥ T3), the dielectric properties of both the cancerous serosa and mucosa were higher than the one restricted to muscularis propria or less intestine wall (stage < T3) over the measured frequency range, and there existed statistical differences at the common frequencies of 213 MHz and 426 MHz. Conclusion The open-ended coaxial line system may result in fast and effective diagnostic differentiation between cancerous and normal colorectal tissues as well as reasonable assessment of the tumor infiltration depth.