title: Comparison of the Intraperitoneal, Retroorbital and per Oral Routes for F-18 FDG Administration as Effective Alternatives to Intravenous Administration in Mouse Tumor Models Using Small Animal PET/CT Studies.
abstract: OBJECTIVE
  We compared alternative routes for (18)F-fluorodeoxyglucose (FDG) administration, such as the retroorbital (RO), intraperitoneal (IP) and per oral (PO) routes, with the intravenous (IV) route in normal tissues and tumors of mice.
  
  
  METHODS
  CRL-1642 (ATCC, Lewis lung carcinoma) cells were inoculated in female BALB/c-nu/nu mice 6 to 10 weeks old. When the tumor grew to about 9 mm in diameter, positron emission tomography (PET) scans were performed after FDG administration via the RO, IP, PO or IV route. Additional serial PET scans were performed using the RO, IV or IP route alternatively from 5 to 29 days after the tumor cell injection.
  
  
  RESULTS
  There was no significant difference in the FDG uptake in normal tissues at 60 min after FDG administration via RO, IP and IV routes. PO administration, however, showed delayed distribution and unwanted high gastrointestinal uptake. Tumoral uptake of FDG showed a similar temporal pattern and increased until 60 min after FDG administration in the RO, IP and IV injection groups. In the PO administration group, tumoral uptake was delayed and reduced. There was no statistical difference among the RO, IP and IV administration groups for additional serial PET scans.
  
  
  CONCLUSIONS
  RO administration is an effective alternative route to IV administration for mouse FDG PET scans using normal mice and tumor models. In addition, IP administration can be a practical alternative in the late phase, although the initial uptake is lower than those in the IV and RO groups.
authors.affiliation: Department of Nuclear Medicine, Hospital, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 South Korea.
authors.forename: Chulhan
authors.initials: C
authors.lastname: Kim
authors.affiliation: Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: In Hye
authors.initials: IH
authors.lastname: Kim
authors.affiliation: Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: Seo-Il
authors.initials: SI
authors.lastname: Kim
authors.affiliation: Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: Young Sang
authors.initials: YS
authors.lastname: Kim
authors.affiliation: Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: Se Hun
authors.initials: SH
authors.lastname: Kang
authors.affiliation: Department of Nuclear Medicine, Hospital, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 South Korea.
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Moon
authors.affiliation: Department of Nuclear Medicine, Hospital, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 South Korea ; Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: Tae-Sung
authors.initials: TS
authors.lastname: Kim
authors.affiliation: Department of Nuclear Medicine, Hospital, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-769 South Korea ; Molecular Imaging and Therapy Branch, Research Institute, National Cancer Center, Goyang-si, South Korea.
authors.forename: Seok-Ki
authors.initials: SK
authors.lastname: Kim
keywords: Administration route; FDG; Intraperitoneal; Intravenous; Per oral; Retroorbital; Small animal PET