Benign Duodenal Leiomyoma Mimicking Malignancy on 68 Ga-FAPI PET/CT.

We present PET/CT findings of a 62-year-old woman with duodenal leiomyoma. 18 F-FDG PET/CT demonstrated a mass with mild FDG uptake at the duodenal papilla (SUV max , 3.7). 68 Ga-FAPI PET/CT showed intense FAPI uptake in the same region (SUV max , 9.6). These imaging findings raised suspicion for malignancy. However, histopathologic examination revealed duodenal leiomyoma. This case highlights that benign duodenal leiomyoma should be included in the differential diagnosis of duodenal FAPI-avid malignant lesions.