[A case of bronchocentric granulomatosis resembling lung cancer on diagnostic imaging].

A 51-year-old man visited a local physician because of a chest radiographic abnormality which had been pointed out in October 2009 and March 2010. His chest CT images revealed a nodular lesion in the right middle lobe. Since the nodular lesion showed abnormal FDG accumulation on FDG-PET, the physician suspected lung cancer, but was unable to make a definitive diagnosis by CT-guided lung biopsy. The patient was thus referred to our hospital for detailed investigations. A nodular lesion with spiculation and pleural indentation was recognized in the S4 region on chest CT scans which was strongly suspected to be lung cancer. Since various examinations did not provide a definitive diagnosis, we performed surgery. The histological findings of the extirpated tumor were considered to be bronchocentric granulomatosis (BCG), because necrotic granulomatous lesions with epithelioid cells centered on the bronchioles and there was no evidence of fungus or acid-fast bacterium infection.