title: 18F-FDG uptake and its clinical relevance in primary gastric lymphoma.
abstract: We studied the clinical relevance of (18)F-fluorodeoxyglucose ((18)F-FDG) uptake in patients with primary gastric lymphoma underwent positron emission tomography (PET)/ computed tomography (CT) scan. Forty-two patients with primary gastric lymphoma were analysed: 32 diffuse large B-cell lymphomas (DLBCL) and 10 extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue (MALT lymphomas). The PET/CT scans were compared with clinical and pathologic features, and the results of CT and endoscopy. Nine patients were up-staged based on the results of their PET/CT scan compared to CT (seven DLBCLs, two MALT lymphomas) while six patients were down-staged by the PET/CT scan. The standard uptake value (SUV) was used as an indicator of a lesion with a high metabolic rate. The high SUVmax group, defined as an SUVmax >or= median value, was significantly associated with an advanced Lugano stage (p < 0.001). Three patients with DLBCL, who showed an initially high SUVmax, died of disease progression. Among 24 patients for whom follow-up PET/CT scan with endoscopy was performed, 11 patients with ulcerative or mucosal lesions showed residual (18)F-FDG uptake. All of these gastric lesions were grossly and pathologically benign lesions without evidence of lymphoma cells. In conclusion, PET/CT scan can be used in staging patients with primary gastric lymphoma; however, the residual (18)F-FDG uptake observed during follow-up should be interpreted cautiously and should be combined with endoscopy and multiple biopsies of the stomach.
authors: Division of Hematology-Oncology, Department of Medicine, Samsung Medical Center, Sungkunkwan University School of Medicine, Seoul, Korea.
authors: Jun Ho
authors: JH
authors: Yi
authors: Seok Jin
authors: SJ
authors: Kim
authors: Joon Young
authors: JY
authors: Choi
authors: Young Hyeh
authors: YH
authors: Ko
authors: Byung-Tae
authors: BT
authors: Kim
authors: Won Seog
authors: WS
authors: Kim
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D005462:Fluorine Radioisotopes / Q000493:pharmacokinetics; D019788:Fluorodeoxyglucose F18 / Q000493:pharmacokinetics; D005753:Gastric Mucosa / Q000000981:diagnostic imaging / Q000473:pathology; D005773:Gastroscopy; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011379:Prognosis; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D013274:Stomach Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D013276:Stomach Ulcer / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D005462:Fluorine Radioisotopes; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18