Increased 68 Ga-FAPI Uptake in Benign Metastasizing Leiomyoma.

Benign metastasizing leiomyomas (BMLs) are benign disseminated extrauterine tumors in patients with prior history of uterine leiomyomas and may occur years after hysterectomy. In this case, we presented 18 F-FDG and 68 Ga-FAPI PET/CT findings in a 37-year-old woman with benign leiomyoma metastasizing to lung and pelvis. The metastatic lesions demonstrated faint 18 F-FDG but elevated 68 Ga-FAPI activity, indicating the low level of glucose metabolism but excessive accumulation of activated fibroblasts in the BMLs. This case demonstrated that 68 Ga-FAPI PET/CT may be potentially useful in the evaluation of BMLs.