Role of FDG PET-CT in detecting recurrence in patients with uterine sarcoma

PURPOSE: The purpose of the present study was to evaluate the role of 18F-fluorodeoxyglucose (FDG) PET-CT in detecting recurrent disease in posttherapy patients of uterine sarcoma and compare the same with conventional imaging (CI). METHODS: A total of 15 FDG PET-CT studies were acquired in 12 posttherapy uterine sarcoma patients. The images were evaluated by two experienced nuclear medicine physicians in consensus. Clinical/imaging follow-up (minimum 6 months) and histopathology were taken as the reference standard. All the patients had also undergone CI (CT or MRI or ultrasonography) of the chest, abdomen, and pelvis. The diagnostic accuracy of FDG PET-CT was calculated and compared with that of CI. RESULTS: The median age of the patients was 51.5 years (interquartile range: 47.5-53). Histopathology was leiomyosarcoma in six, carcinosarcoma in five, and endometrial stromal sarcoma in one patient. Six FDG PET-CT studies were carried out for suspected recurrence and nine for posttherapy surveillance. Six FDG PET-CTs were positive and nine were negative for recurrence. The sensitivity, specificity, and accuracy of FDG PET-CT were 85.7, 100, and 93.3%, respectively, on per study-based analysis, and 80, 100, and 83.3% on per lesion-based analysis. PET-CT showed higher sensitivity and specificity compared with CI for both study-based and lesion-based analysis. However, no significant difference was found between FDG PET-CT and CI either in the study-based or in the lesion-based analysis (P not significant). CONCLUSION: FDG PET-CT is a highly sensitive and specific modality for detecting recurrence in posttherapy patients with uterine sarcoma. However, it provides no significant advantage over CI for this purpose.