The implementation of ambient mass spectrometry profiling techniques for assistance on surgery in precise identification of pathological modifications of tissues is recognized as an essential step towards the arise of prospective medicine. However, transfer the mass spectrometry techniques to a clinic, and their integration with clinical protocols and regulations require particular investigations. In this work, the author's experience of the development of the approaches to applying mass spectrometry profiling in neurosurgery was summarized.
The research was conducted on the basis of N.N. Burdenko National Medical Research Neurosurgery Center in accordance with local and international ethics guidelines. Samples of brain tumor tissues resected during elective surgery were analyzed using custom designed Inline Cartridge Extraction system followed by ESI to register lipid profiles. More than 300 samples from more than 150 patients were analyzed in 2018-2019.
Each resected tissue sample was divided into three parts - one of them analyzed immediately on the low-resolution instrument in the clinic, second was examined by the pathologist while the third one was frozen and transferred to the remote laboratory for an investigation with the high-resolution mass spectrometer. All data were accumulated in a database that allows to compare and analyze results of low-resolution lipid profiling of recently resected sample, high-resolution lipid profiles of frozen samples investigation with histological annotations and the results of ms/ms analysis of conventionally extracted lipids and metabolites. Despite the variations in spectra which originates in biological variability and artificial alterations (e.g., time passing between the moment of the resection and tissue analysis) sustainable combinations of peaks are still present in spectra. Combinations of these stable characteristic peaks is shown to be suitable for reliable automated tissue classification. Performed investigations demonstrate the possibility to apply ambient mass spectrometry to neurosurgical operations using high-resolution data as well as low-resolution ones.