Purpose:
To describe systemic sarcoidosis lesions revealed through whole body 18-Fluorodeoxyglucose (FDG) positron emission tomography/computed radiographic tomography (PET/CT) imaging.
Methods:
We performed a retrospective review of 4 ocular tumor patients evaluated with PET/CT for metastatic disease. Each had a history of or was diagnosed with systemic sarcoidosis. Two were under treatment for conjunctival melanoma and 2 presented with atypical choroidal tumors. We used PET/CT to stage each patient. PET/CT images were studied for presence of increased 18-FDG concentration. Elevated standardized uptake values (SUV) typically greater than or equal to 2.5 were considered positive. High SUV levels indicate increased metabolism (glucose consumption).
Results:
In all cases, PET-CT revealed increased systemic 18-FDG uptake with SUV values ranging from 1.7 to 5.9. Patient demographics, ocular findings and sites of activity are summarized in the Table. Patients 1 and 2 had a previous diagnosis of systemic sarcoidosis (without clinically apparent ocular involvement), while patients 3 and 4 were newly diagnosed. PET/CT is shown to reveal the presence and distribution of clinically apparent and occult sarcoid granulomas.
Conclusions:
PET/CT is a powerful imaging modality for staging ocular and nonocular cancers. It has been found to detect synchronous non-ocular primary cancer and inflammatory disease. In this series, PET/CT helped in the diagnosis and staging of patients with systemic sarcoidosis.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • tumors • imaging/image analysis: clinical