Simultaneous use of FDG-18 and Ga-68-citrate PET/CT for the differential diagnosis of sarcoidosis and malignant disease

Abstract

A 67-year-old male presented with cutaneous rash, lassitude and fatigue of three weeks. Personal history included psoriasis and sarcoidosis. Physical examination revealed macular rash on the anterior chest wall. Laboratory results were within normal limits. Chest X-ray showed normal findings. Pulmonary function tests demonstrated a mild obstructive pattern and a mild decrease in DLCO/VA. Thorax CT revealed two nodules in the right upper and middle lobe. Ga-68-citrate PET/CT did not demonstrate any active inflammatory reaction associated with sarcoidosis while F-18-FDG PET/CT revealed increased FDG uptake in the right middle lobe, upper division bronchus and in the left lower abdominal quadrant. Histopathologic examination of the colon biopsy was compatible with adenocarcinoma and bronchoscopic biopsy of the lung lesions revealed nonspecific granulomatous inflammation. BAL cytology was normal while BAL culture did not grow any pathologic organisms.