Objective: In this study, the role of GLUT1 expression in synovial sarcomas and its association with disease pathogenesis were examined.

Materials and Methods: Twenty two cases of synovial sarcoma were included in this study. The clinicopathological features of the cases, such as age, sex, localization of tumor, information of primary or metastatic tumor, histopathological type were recorded. The tissue microarray paraffin block containing tumor tissues was built by using tissue microarrayer. GLUT1 expression was analyzed on tissue sections by immunohistochemistry.

Results: A total of 22 cases (mean age 36 years; range 14-54 years) were analyzed. All cases except one were primary tumors. The tumors showed monophasic histological type in 13 cases and biphasic type in 9 cases. GLUT1 expression was found in 3 cases with biphasic type (14%). The cytoplasmic and incomplete membranous GLUT1 expression was seen in the tumor cells showing epithelial-glandular differentiation, whereas spindled cells were negative.

Conclusion: Although GLUT1 expression is a diagnostic marker for juvenile capillary hemangioma and perineural tumors, both of which included in the group of mesenchymal tumors, it can be seen in a subset of synovial sarcomas. In our series, the observation of GLUT1 expression especially in the epithelial component of biphasic synovial sarcomas suggests that; i) GLUT1 may be relatively used by tumoral cells composing epithelial component of the tumor, and ii) the spindle cell component of the tumor would have been positive for other glucose transporters. The finding of uncommon GLUT1 expression in synovial sarcomas is indirectly consistent with the reported results of decreased standardized uptake value by Positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose method in the literature.