Pulmonary cryptococcosis and tuberculoma mimicking primary and metastatic lung cancer in 18F-FDG PET/CT

Abstract

18F-fluorodeoxyglucose positron emission tomography (FDG-PET) has been widely incorporated in cancer management. Although, it has increased sensitivity, 18F-FDG is not tissue specific thus posing diagnostic dilemma in certain situations. False positivity in pulmonary nodules have been seen in various inflammatory, infective as well as post operative conditions while false negativity is common with adenomas, low grade lymphomas, bronchoalveolar carcinomas and carcinoid tumors. We present two cases of granulomatous diseases as pulmonary cryptococcosis and tuberculosis showing false positivity in a resected colorectal cancer patient and highlight the importance of recognition of this entity in an endemic region for granulomatous infections.