Unusual FDG PET/CT Uptake in Uterine Tumors in Cancer Survivor

Abstract

18-Fluorodeoxyglucose positron emission tomography/computed tomography (18-FDG PET/CT) has become the essential modality of imaging in diagnosis; it is used for assessment of treatment response, after chemotherapy, as well as for prognostic evaluation. Case 1 is a postmenopausal woman treated for the case of Langerhans cell sarcoma; she received chemotherapy; post-chemotherapy PET/CT scan was done to assess the response to chemotherapy with an SUV of 7.1 in the uterus. The rest of the report showed no uptake elsewhere in the body, and hysterectomy with BSO pathological report showed benign leiomyoma. Case 2 is treated for carcinoma thyroid by surgery and radioiodine ablation therapy. She was on regular follow-up, and she is a premenopausal multiparous woman with regular menstruation and on annual PET/CT examination incidentally showed an increased SUV of 8 in the uterus. There was no FDG uptake elsewhere in the body except for uterus. False-positive uptake of 18-FDG PET/CT in uterine tumors can be seen in leiomyoma which has high SUV of more than 6. Surgical management with histopathological confirmation of leiomyoma is needed in cases treated for malignancy elsewhere in the body; we report these two cases hoping to expand the existing knowledge on the topic and highlight the limitation of PET/CT in the diagnosis of leiomyoma.