Diagnosis and evaluation of gastric cancer by positron emission tomography

Figure 1 ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography for evaluation of response to neoadjuvant chemotherapy. ¹⁸F-fluorodeoxyglucose (FDG) tomography/computed tomography (PET/CT) imaging of a responder patient before (A) and after three cycles of chemotherapy (B); After therapy, the patient showed significant tumor SUV reduction (A: SUV_max = 4.1, B: SUV_max = 2.1, %∆SUV = 37.3%), corresponding to his histological response (Grade 2b) according to the JRSGC (Japanese Research Society for Gastric Carcinoma) criteria; FDG PET/CT imaging of a non-responder patient before (C) and after three cycles of chemotherapy (D); The tumor SUV was the same after therapy (C: SUV_max = 9.2, B: SUV_max = 9.7, %∆SUV = -5.4%), corresponding to his histological response (Grade 0) according to the JRSGC criteria. SUV: Standardized uptake value.

Figure 2 ¹⁸F-fluorodeoxyglucose positron emission tomography imaging of gastric cancer under gastric distention. A small size gastric tumor (arrow, 1.5 cm × 1.2 cm, highly differentiated gastric adenocarcinoma) was clearly observed with low background gastric wall uptake due to gastric distention (A-C).