Simultaneous splenic and colonic metastases from gastric cancer: different FDG avidities according to the density of cancer cells imaged on FDG PET/CT.

We describe the ¹⁸F-FDG PET/CT findings of 2 simultaneous metastatic gastric cancers to the colon and spleen with quite different FDG avidities. Longitudinal and weak FDG uptake was observed in the descending colon; therefore, it could not be distinguished from nonpathological functional uptake of normal colon. Meanwhile, the splenic mass showed intense uptake. Contrast-enhanced CT revealed a segmental wall thickening of the descending colon as well as a hypoattenuating splenic mass suggesting metastases. Splenectomy and left hemicolectomy were performed. Histological diagnosis disclosed metastatic gastric cancer. The differential diagnoses and review of the literature are presented.