Raman spectroscopy for colorectal tumor margin assessment: A promising tool for real-time surgical delimitation

Raman spectroscopy is a promising non-invasive technique not only for the rapid and accurate detection of colorectal cancer (CRC) but also for the identification of positive surgical margins. In this study, micro-Raman spectroscopy was used to explore biochemical differences in surgically resected intestinal segments, with a focus on boundary tumor zone. Spectral and statistical analyses, including Partial least squares discriminant analysis (PLS-DA), were performed to identify significant molecular signatures and distinguish different tissue types. Our findings suggest that boundary tumor zone contain a mix of cancerous and normal cells, complicating the discrimination of these regions. Despite this challenge, we achieved a classification accuracy of 82 % for tumor margin differentiation from normal tissue along with identifying several biochemically significant spectroscopic differences. Rapid Raman measurements using a portable system, taken from resected tissues immediately after surgery, further demonstrated the technique's ability to differentiate cancerous from healthy tissues with 97 % accuracy, 98 % sensitivity, and 96 % specificity, underscoring the potential of Raman spectroscopy for real-time clinical applications in CRC surgery.