@misc{oai:repo.qst.go.jp:00069908,
 author = {Tanimoto, Katsuyuki and Yoshikawa, Kyosan and Obata, Takayuki and Toubaru, Sachiko and Ohashi, Seiya and Hasebe, Mitsuhiko and Shiraishi, Takahiro and Watanabe, Kazuhiro and Saga, Tsuneo and Ikehira, Hiroo and Mizoe, Junetsu and Kamada, Tadashi and Tsujii, Hirohiko and Miyazaki, Masaru and et.al and 谷本 克之 and 吉川 京燦 and 小畠 隆行 and 桃原 幸子 and 大橋 靖也 and 長谷部 充彦 and 白石 貴博 and 渡邊 和洋 and 佐賀 恒夫 and 池平 博夫 and 溝江 純悦 and 鎌田 正 and 辻井 博彦 and 宮崎 勝},
 month = {Oct},
 note = {Objectives
FDG-PET provides quantitative information about tumor glucose utilization witch is useful for clinical diagnosis of tumor diseases. Standardized Uptake Value (SUV) is most commonly used for evaluation of tumor glucose utilization. But, SUV is affected by many factors that cannot be controlled or even taken into account. In that respect, brain reference index (BRI: ROI of tumor / ROI of cerebellum) is one of the novel quantitative approaches to eliminating the variety of factors that affect SUV. Meanwhile, a MRI pulse sequence could reveal the information about tissue cellularity. This information is useful to evaluate tumor nature. It suggests that it can be useful in the evaluation of malignancy in the lesions. We compared the role of glucose metabolism and cellularity for detection of pancreatic tumor malignancy.
Materials and Methods
PET/CT: Toshiba Aquiduo, LSO crystals, 3D acquisition mode: 3min, OS-EM Iteration: 4, Subset: 14, Gaussian post filter: 8.0mm
16 Multidetector-row CT, 120kV, Automatic exposure control (160 effective mAs), Helical pitch: 15mm/rot.
MRI: GE healthcare Signa HDx 3T
Pre-surgery patients with primary pancreatic tumor underwent a whole body FDG-PET/CT and 3Tesla MRI. The malignancy or benignancy of excised specimens was pathologically confirmed in all cases. Tumor glucose utilization was evaluated with SUV and BRI in FDG-PET/CT study, and tumor cellularity was determined with MRI factors, apparent diffusion coefficient (ADC), T2 value and tumor to non-tumor ratio of proton density (TNRPD) in MRI study.
ADC were measured with a diffusion weighted image (DWI) using a spin-echo echo-planar sequence (TR=10s; TE=80ms; b factor=0, 400, 800,1200s/mm2).
T2 value and proton density were measured with a spin-echo sequence (TR=3s; TE=40, 60, 80, 100ms).
We calculated TNRPD from proton density values of tumor and normal pancreas.
We compared these results with pathological findings.
Results
FDG uptake tended to be higher in malignant tumor than benign tumor. BRI seemed to distinguish malignant lesions from benign lesions more clearly than SUV alone. ADC was lower in malignant tumor than benign tumor. Malignant tumors showed higher TNRPD than benign tumors.
Conclusions
The tumor that shows high SUV, high BRI, low ADC, high TNRPD, high T2WI and high DWI indicate a high probability of pancreatic tumor malignancy. 
FDG-PET/CT in combination with MRI was superior to each modality alone for evaluating tumor malignant nature., The 2009 EANM Congress},
 title = {Comparison of Glucose metabolism measured by FDG-PET/CT and Cellularity obtained from MRI for malignancy evaluation of pancreatic tumor},
 year = {2009}
}