Objectives: The objectives of this study were to assess the maximum standardized uptake value (SUVmax) of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) by a primary tumor of endometrial cancer with the use of positron emission tomography/computed tomography (PET/CT) and to assess its association with the clinical importance of the disease.

Methods: ¹⁸F-fluorodeoxyglucose PET/CT scan was performed on 44 participants within 2 weeks before surgery. ¹⁸F-fluorodeoxyglucose uptake was quantified by calculating the SUVmax. The distribution of cases that scored positive for each of the biological parameters examined was correlated with the SUVmax of the ¹⁸F-FDG PET/CT and the glucose transporter-1 expression status obtained by immunohistochemistry.

Results: The mean SUVmax of the primary endometrial cancer tumors was 17.6 (range, 3.04-34.74). There were significant correlations between the SUVmax of the primary tumor and the International Federation of Gynecology and Obstetrics (FIGO) grade (P < 0.001), maximum tumor size (P < 0.001), and glucose transporter-1 expression (P < 0.001). Furthermore, multivariate analysis showed that the FIGO grade was most significantly identified as a relation factor of SUVmax (≥17.6) for endometrial cancer (P = 0.017). The present findings indicate that a significant relationship was seen between the SUVmax and the FIGO grade in endometrial cancer.

Conclusion: We propose that the primary tumor's SUVmax obtained from ¹⁸F-FDG PET/CT may be associated with aggressive biological characteristics in endometrial cancer.