Sarcoma Molecular Pathological Diagnosis of FFPE Tissues without Dewaxing based on Lipidomic Proles using SpiderMass Technology
Background :Formalin-xation and paran-embedding (FFPE) is the worldwide gold standard for tissue preservation and routine pathology for general and cancer diagnostics. Despite robust histopathology methods, accurate diagnostic remains dicult for certain cases. Overall, the entire process is timeconsuming, labor-intensive and doesn’t reach the right sensitivity and specicity. Lipids are central players in cancer, but they are not routinely used in diagnostics because of the sample processing which limits their detection, and lipid analysis directly from unprocessed FFPE tissues has never been reported. Methods :We present a new method for cancer diagnostics based on tissue-lipidomic signatures through rapid screening of FFPE without dewaxing using Water-Assisted Laser Desorption Ionization Mass Spectrometry (WALDI-MS) and deep-learning. Results :We show on a cohort of canine and human sarcoma tissues that classication for sarcoma subtyping is possible and enables diagnosing blind samples in less than ve minutes, with over 95% probability to discriminate specic subtypes. Conclusion: We have revealed the possibility to create a rapid diagnostic platform to screen clinical FFPE tissues with minimal sample preparation for molecular pathology.