# Imaging of colorectal adenomas with pseudoinvasion and malignant polyps using two-photon excitation microscopy

## TL;DR

This study uses two-photon excitation microscopy to distinguish between malignant polyps and those with pseudoinvasion in colorectal cancer.

## Contribution

The paper introduces TPEM as a novel method to visualize stromal changes and differentiate true invasion from pseudoinvasion in colorectal polyps.

## Key findings

- TPEM images showed distinct collagen distribution and density at the invasion front in malignant polyps.
- TPEM can help distinguish true invasion from pseudoinvasion by visualizing local stromal changes.
- Subjective and quantitative analyses confirmed differences in collagen patterns between malignant and pseudoinvasive polyps.

## Abstract

Although the incidence and mortality rates of colorectal cancer exhibit significant variability, it remains one of the most prevalent cancers worldwide. Endeavors to prevent colorectal cancer development focus on detecting precursor lesions during colonoscopy. The diagnosis of endoscopically resected polyps relies on hematoxylin and eosin staining examination. For challenging cases like adenomatous polyps with epithelial misplacement, additional diagnostic methods could prove beneficial.

This paper aims to underscore stromal changes observed in malignant polyps and polyps with pseudoinvasion, leveraging two-photon excitation microscopy (TPEM), a technique extensively employed in the medical field in recent years.

Both the subjective and quantitative analysis of TPEM images revealed distinct distributions and densities of collagen at the invasion front in malignant polyps compared to areas of pseudoinvasion. TPEM holds potential in discerning true invasion in malignant polyps from pseudoinvasion, offering enhanced visualization of local stromal changes.