Melanin-Targeted PET Imaging Sheds Light on Pigment Epithelioma in Corpus Ciliare

A 57-year-old woman had gradually decreased visual acuity in the left eye, accompanied by distension and pain. MRI demonstrated a small neoplasm in corpus ciliare, which promoted PET imaging for further assessment. 18F-FDG PET imaging found no obvious uptake in the lesion. However, melanin-targeted PET imaging demonstrated the lesion with avid 18F-PFPN (18F-N-(2-diethylaminoethyl)-4-(2-[2-ethoxy]-ethoxy)pyridine) accumulation (SUVmax, 7.1), which suggested it with melanin expression. Pigmented epithelial adenoma was further confirmed by pathology. Our case illustrated that pigmented epithelial adenoma is characterized by avid 18F-PFPN accumulations and can be detected even in a hidden location with a size of ≤5 mm.