Infrared Laser Sampling of Low Volumes Reveals Marker Lipids in Palatine Tonsil Carcinoma via Shotgun Lipidomics

Complete surgical resection is essential for oropharyngeal squamous cell carcinoma (OPSCC) therapy, underscoring the need for improved intraoperative margin assessment. To advance in-vivo diagnostics of OPSCC, Nanosecond infrared laser (NIRL) tissue sampling combined with shotgun lipidomic analysis reveals lipidome differences between OPSCC tissue and adjacent healthy tissue. Ablations were performed on tonsil squamous cell carcinoma on n=28 samples from 11 patients with an established chamber setup and a subset of n=6 samples from three patients with a custom-made handheld applicator. Welchs t-test results (p=0.05, two-fold change) revealed a similar OPSCC lipid profile in 7 of 11 patients. Potential tumor lipid markers were identified as consistently significantly increased, despite biological heterogeneity of the samples, underscoring their potential diagnostic value. Tissue ablation with a custom-made handheld applicator coupled to a laser fiber was successful and the lipidomic analysis was consistent to the chamber setup. Although our setup is currently limited by an ablation time exceeding one minute, this study demonstrates the potential of the handheld applicator for future applications such as endoscopy or intraoperative diagnostics.