Significance of (18)F-2-deoxy-2-fluoro-glucose accumulation in the stomach on positron emission tomography.
OBJECTIVE
To explain the accumulation of (18)F-2-deoxy-2-fluoro-glucose ((18)FDG) on positron emission tomography (PET) in the stomach and differences in its pattern, we focus on the accumulation pattern in association with endoscopic findings of the gastric mucosa and Helicobacter pylori (Hp) infection.


METHODS
Of 599 cases undergoing (18)FDG-PET examinations, we retrospectively analyzed the pattern of (18)FDG accumulation in the stomach, findings of upper gastrointestinal endoscopy, and Hp infection. The pattern of (18)FDG accumulation was classified into three groups: localized accumulation only in the fornix (Group A, 32 patients), diffuse accumulation throughout the entire stomach (Group B, 49 patients), and no accumulation (Group C, 191 patients).


RESULTS
Regarding the relation between Hp infection and (18)FDG accumulation, Hp infection was positive in 56.3% of Group A, 73.5% of Group B, and 24.1% of Group C, with significant differences (p < 0.001). Regarding the relation between (18)FDG accumulation and gastric mucosal inflammation, when Groups A and B were compared with Group C, nearly half of the cases in the former groups had papular redness with a significantly higher frequency of redness and erosion. Three cases found to have malignant tumor were limited to the former groups. One MALT lymphoma case was also found in the same group. Accumulation of (18)FDG largely corresponded to mucosal inflammation including superficial gastritis and erosive gastritis, and therefore the main cause of non-specific (18)FDG accumulation was considered to be inflammatory mucosa (mainly redness). The accumulation pattern was not associated with atrophic changes of the gastric mucosa or with Hp infection, but with mucosal inflammatory changes, including redness and erosion localized to the fornix.


CONCLUSIONS
Accumulation of (18)FDG in the stomach suggests a high probability of the presence of inflammatory change in the gastric mucosa forming a background for the development of cancer or malignant lymphoma, and thus requires further endoscopic examinations.
Takahashi
Hiroshi
H
Department of Cancer Screening Center, Cancer Institute Hospital of Japanese Foundation for Cancer Research, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan. hiroshi.takahashi@jfcr.or.jp
Ukawa
Kunio
K
Ohkawa
Nobuhiko
N
Kato
Kaoru
K
Hayashi
Yuuko
Y
Yoshimoto
Kazuhito
K
Ishiyama
Akiyoshi
A
Ueki
Nobuko
N
Kuraoka
Kensuke
K
Tsuchida
Tomohiro
T
Yamamoto
Yorimasa
Y
Chino
Akiko
A
Uragami
Naoyuki
N
Fujisaki
Junko
J
Igarashi
Masahiro
M
Fujita
Rikiya
R
Koyama
Masamichi
M
Yamashita
Takashi
T
D016099:Endoscopy, Gastrointestinal; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism / Q000493:pharmacokinetics*; D005753:Gastric Mucosa / Q000000981:diagnostic imaging / Q000378:metabolism*; D005757:Gastritis, Atrophic / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D016481:Helicobacter Infections / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D016480:Helicobacter pylori; D006801:Humans; D007249:Inflammation / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D013270:Stomach / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000473:pathology / Q000601:surgery
D019788:Fluorodeoxyglucose F18