1Division of Cancer Imaging Research, Department of Radoilogy, Johns Hopkins School of Medicine, BALTIMORE, MD, United States; 2FOM-Institute AMOLF, Amsterdam, Netherlands; 3Division of Cancer Imaging Research, Department of Radoilogy, Johns Hopkins University, BALTIMORE, MD, United States
The intensity of the total choline (tCho) signal in magnetic resonance spectroscopic imaging (MRSI) of tumors is spatially heterogeneous. In vivo H1 MRSI with the spectral resolution to resolve the components of the tCho signal and its membrane precursors is currently unavailable. Mass spectrometry imaging (MSI) of histologic tumor sections is able to detect thousands of molecules from the tissue surface. We have investigated the correlations between tCho and peptides in a human breast cancer model by combining in vivo MRSI with ex vivo MSI, which identified specific peptide species that are spatially correlated with tCho.