Role of respiratory-gated PET/CT for pancreatic tumors: a preliminary result.
OBJECTIVE
The aim of this study is to ascertain role of respiratory-gated PET/CT for accurate diagnosis of pancreatic tumors.


METHODS
Prior to clinical study, the phantom study was performed to evaluate the impact of respiratory motion on lesion quantification. Twenty-two patients (mean age 65 years) with pancreatic tumors were enrolled. Pathological diagnoses by surgical specimens consisted of pancreatic cancer (n=15) and benign intraductal papillary mucinous neoplasm (IPMN, n=7). Whole-body scan of non-respiratory-gated PET/CT was performed at first, and subsequent respiratory-gated PET/CT for one bed position was performed. All PET/CT studies were performed prior to surgery. The SUV max obtained by non-respiratory-gated PET/CT and respiratory-gated PET/CT, and percent difference in SUVmax (%SUVmax) were compared.


RESULTS
The profile curve of 5 respiratory bin image was most similar to that of static image. The third bin of 5 respiratory bin image showed highest FWHM (24.0mm) and FWTM (32.7 mm). The mean SUVmax of pancreatic cancer was similar to that of benign IPMN on non-respiratory-gated PET/CT (p=0.05), whereas significant difference was found between two groups on respiratory-gated PET/CT (p=0.016). The mean %SUV of pancreatic cancer was greater than that of benign IPMN (p<0.0001). Identification of the primary tumor in pancreatic head (n=13, 59%) was improved by using respiratory-gated PET/CT because of minimal affection of physiological accumulation in duodenum.


CONCLUSIONS
Respiratory-gated PET/CT is a feasible technique for evaluation of pancreatic tumors and allows more accurate identification of pancreatic tumors compared with non-respiratory-gated PET/CT.
Department of Radiology, Yokohama City University Graduate School of Medicine, 3-9, Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004, Japan. kasumakidon@yahoo.co.jp
Takeo
T
Kasuya
Ukihide
U
Tateishi
Kazufumi
K
Suzuki
Hiromitsu
H
Daisaki
Yuji
Y
Nishiyama
Masaharu
M
Hata
Tomio
T
Inoue
D000368:Aged; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods*; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D010865:Pilot Projects; D049268:Positron-Emission Tomography; D015203:Reproducibility of Results; D055425:Respiratory-Gated Imaging Techniques / Q000379:methods*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed