Possible involvement of glucose transporter 3 and 4 in esophageal leiomyoma with unusual high uptake of fluorine-18-fluorodeoxyglucose: Three case reports

There were esophageal benign leiomyomas that showed unusual uptake of fluorine-18-fluorodeoxyglucose (FDG). Three patients received enucleation or resection of esophageal submucosal tumors and these were confirmed as benign leiomyomas pathologically. Preoperative FDG-PET examination of the two patients revealed that maximum standardized uptake values (SUV_max) of the tumor were 5.83 and 5.57. Both tumors had strong expression of glucose transporter (Glut)-3 and Glut-4. The other one patient showed low uptake of FDG and weak expression of Glut-3 and Glut-4. Interestingly, all three tumors had negative expression of Glut-1 and Glut-2. Furthermore, cultured leiomyoma cells (TYLeio-3) from the patients with high uptake of FDG had strong expression of Glut-3, weak expression of Glut-4 and no expression of Glut-1. Our results suggested that the expression of Glut-3 and Glut-4, but not Glut-1, may be one of the reasons for unusual uptake of FDG in benign esophageal leiomyoma.