Selective Laser Ablation of Malignant Solid Tumors Tuned to the Resonant Wavelength of Collagen.

Laser ablation is progressively introducing novel therapeutic approaches for treatment of solid tumors. Recently, our previous research demonstrated that mid-infrared femtosecond lasers tuned to the collagen resonance wavelength can selectively ablate solid tumors. However, the mechanisms underlying selectivity, as well as its potential clinical relevance, remain insufficiently understood. In this study, systematic investigations have been conducted on three orthotopic mice models of solid tumors: glioma, pancreatic ductal adenocarcinoma (PDAC), and colorectal cancer, employing a 6.1 μm femtosecond laser resonant with collagen. Selective ablation is observed in glioma and PDAC, but not in colorectal cancer, which is attributed to the markedly increased collagen content, particularly Collagen I, relative to their corresponding normal tissues, a disparity that is not present in colorectal cancer. Further analysis of clinical specimens through multiplex immunofluorescence and gene expression supports the translational potential of this collagen-mediated selective laser ablation mechanism, suggesting its applicability for tumor-targeted therapeutic interventions.