Oxygen saturation imaging as a useful tool for visualizing the mode of action of photodynamic therapy for esophageal cancer.

ABSTRACT:

Background and aims

Oxygen saturation (OS) imaging is a novel technique that directly measures and visualizes the tissue oxygen saturation at the surface of the GI tract. Our purpose was to evaluate the ability of OS imaging to visualize the action mode of photodynamic therapy (PDT).

Methods

Eight patients with local recurrence after chemoradiotherapy for esophageal cancer were enrolled. OS imaging observation was performed before PDT, after 100 J/cm² illumination and illumination completion, and on the second day.

Results

OS imaging showed an extreme change in the hypoxic state in the illuminated area, although the change was near invisible on white-light imaging. The median tissue oxygen saturation value at the tumor lesion was 61.5% (range, 36%-91%) before PDT and significantly decreased immediately after illumination: 11% (range, 0%-57%) after 100 J/cm² illumination, 1% (range, 0%-6%) at PDT completion, and 2% (range, 0%-12%) on the second day.

Conclusions

OS imaging could be a useful tool to visualize changes after PDT.

SUBMITTER: Suyama M 

PROVIDER: S-EPMC7572618 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature