[ 18 F]SiTATE Uptake in a Pancreatic Metastasis From a Renal Cell Carcinoma on a Long Axial Field of View PET/CT.

Abstract

Here we present a 61-year-old woman with a history of renal cell carcinoma after nephrectomy and complete response to immunotherapy. Follow-up MRI revealed a contrast-enhanced lesion in the pancreatic tail, suspicious for a pancreatic neuroendocrine tumor. Subsequently, a SSTR-PET/CT with [ 18 F]SiTATE was conducted on a Biograph Vision Quadra. The pancreatic lesion showed intensive tracer uptake. Thus, a pancreatic tail resection was performed. Histopathologic results revealed no synaptophysin expression, but positivity for PAX8 and carboanhydrase 9. The final diagnosis was a solitary metastasis of the known renal cell carcinoma with SSTR2 expression in the intratumoral vascular network, explaining the [ 18 F]SiTATE uptake.