Marwa Munem oral presentation (OB3-Tue4-2-3)
Studying Basal Skin Cancer by Imaging Lipids and Metabolites using ToF-SIMS
University of Gothunberg, kemivägen 10, 41258 Gothenburg, Sweden
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is starting to be of increasing value to clinicians and has been used on a number of tissue samples to successfully identify and localise different chemical components to various areas of the tissue and answer disease related questions . Compared to other methods, the main advantage of ToF-SIMS is the label free detection of a large number of different molecules within one experiment on the same tissue section. ToF-SIMS is coming closer to the MALDI regime but without the need of a matrix and with generally better spatial resolution . ToF-SIMS has been successfully used for analysing lipids behaviour in biological samples like breast cancer tissue . Basal cell carcinoma is one of the most increasing cancers worldwide and it is the most common malignancy in white people. Although the mortality is low as basal cell carcinoma rarely metastasises, this malignancy causes considerable morbidity and places a huge burden on healthcare services worldwide. Furthermore, people who have this condition are at high risk of developing further basal cell carcinoma and other malignancies .
Samples were collected from patients with basal cell carcinoma, by Mohs surgery. The tissue was cryo-sectioned for ToF-SIMS analysis and H&E staining of consecutive tissue slices was performed. ToF-SIMS was performed using an Ionoptika J105 instrument using a 40 keV (CO2)6000+ ion beam. The analysis provided detailed chemical information about the individual lipid species and the spatial distribution of these within the tissue. It was possible to detect differences between the layers of the skin as well as between healthy and cancerous tissue (see Figure 1). It was also useful to compare the observations of species to H&E stained images, to understand and confirm, from which structures or regions of the tissue that the individual signals were originated.