In vivo proton MR spectroscopy of pancreatic neuroendocrine tumors in a multiple endocrine neoplasia type 1 conditional knockout mouse model

PurposeMR spectroscopy (MRS) can improve diagnosis and follow treatment in cancer. However, no study has yet reported application of in vivo H-1-MRS in malignant pancreatic lesions. This study quantitatively determined whether in vivo H-1-MRS on multiple endocrine neoplasia type 1 (Men1) conditional knockout (KO) mice and their wild type (WT) littermates could detect differences in total choline (tCho) levels between tumor and control pancreas. MethodsRelative tCho levels in pancreatic tumors or pancreata from KO and WT mice were determined using in vivo H-1-MRS at 9.4 T. The levels of Cho-containing compounds were also quantified using in vitro H-1-NMR on extracts of pancreatic tissues from KO and WT mice, respectively, and on extracts of pancreatic tissues from patients with pancreatic neuroendocrine tumors (PNETs). ResultstCho levels measured by in vivo H-1-MRS were significantly higher in PNETs from KO mice compared to the normal pancreas from WT mice. The elevated choline-containing compounds were also identified in pancreatic tumors from KO mice and tissues from patients with PNETs via in vitro H-1-NMR. ConclusionThese results indicate the potential use of tCho levels estimated via in vivo H-1-MRS in differentiating malignant pancreatic tumors from benign tumors. Magn Reson Med 74:1221-1226, 2015. (c) 2014 Wiley Periodicals, Inc.