Nodular fasciitis mimicking soft tissue metastasis on 18F-FDG PET/CT during surveillance.

Nodular fasciitis (NF) is a common benign soft tissue tumor. However, F-FDG PET/CT findings of NF are limited. Two cases of NF are described that mimic soft tissue metastasis on F-FDG PET/CT during surveillance. F-FDG PET/CT is well documented in the surveillance of malignancy and increasing worldwide. There are growing chances of encountering FDG-avid nonmalignant soft tissue lesion. Nodular fasciitis could be considered as possible diagnosis on F-FDG PET/CT if a solitary well- circumscribed ovoid hypermetabolic soft tissue lesion is located in a muscle, intermuscular space, or adjacent tendon, especially in patients with a clinically low probability of tumor recurrence or metastasis.