Compatibility of CO₂ laser surgery and fluorescence detection in head and neck cancer cells.

Abstract

Surgical treatment of cancer requires tumor excision with emphasis on function preservation which is achieved in (early stage) laryngeal cancer by transoral carbon dioxide (CO₂ ) laser surgery. Whereas conventional laser surgery is restricted by the surgeon's visual recognition of tumor tissue, new approaches based on fluorescence-guided surgery (FGS) improve the detection of the tumor and its margin. However, it is unclear whether fluorophores are compatible with high-power laser application or whether precision is compromised by laser-induced bleaching of the dye. We applied topology-controlled 3D laser resection of fluorescent tumors cell in vitro and laser-induced autofluorescence analysis ex vivo. Laser-induced bleaching of fluorescent dyes in the visible and near-infrared light spectrum (650-900 nm) ranges below the resolution range of operation microscopes. Furthermore, specific fluorescent signals in an FGS mouse model is 10⁴ higher than laser-induced autofluorescence in mouse tissue. Laser-induced lateral photobleaching is negligible indicating a path forward for fluorescence-guided laser surgery in head and neck cancer.