68Ga-FAPI-04 PET/MRI in a Case of Tuberous Sclerosis Complex With Extrarenal Retroperitoneal Angiomyolipoma

Extrarenal retroperitoneal angiomyolipomas are rare benign tumors that may mimic other benign or malignant retroperitoneal tumors. We describe Ga-68-FAPI-04 PET/MRI findings in a case of tuberous sclerosis complex with an extrarenal retroperitoneal angiomyolipoma and multiple angiomyolipomas involving bilateral kidneys. The extrarenal retroperitoneal angiomyolipoma and most of the renal angiomyolipomas were Ga-68-FAPI-04-avid. One left renal angiomyolipoma with extensive hemorrhage and fibrosis had no significant Ga-68-FAPI-04 uptake. Angiomyolipoma should be included in the differential diagnosis of FAPI-avid renal or extrarenal retroperitoneal lesions.

Automated summary

We report a case of tuberous sclerosis complex with multiple angiomyolipomas involving bilateral kidneys and an extrarenal retroperitoneal angiomyolipoma. The Ga-68-FAPI-04 PET/MRI showed that the extrarenal tumor and most of the renal tumors were positive, suggesting the consideration of angiomyolipomas in the differential diagnosis of FAPI-avid renal or extrarenal retroperitoneal lesions.