CLINICAL IMAGE

A 51-year-old man was referred to our department because of dyspnoea on exertion and haemoptysis. Chest radiography showed consolidation in the left middle lung field. Chest computed tomography (CT) showed subpleural band-like consolidation and reticular shadows along with paraseptal emphysema in the left lung (Figure 1A). Although we suspected interstitial pneumonia, asymmetric consolidation and the symptom of haemoptysis were not appropriate for interstitial pneumonia. Bronchoscopy was performed, and a diagnosis of adenocarcinoma was made by brush cytology (Figure 2). He was diagnosed with primary lung adenocarcinoma (cT4N3M0) and achieved a partial response after the initiation of the combination chemotherapy of carboplatin and pemetrexed sodium hydrate (Figure 1B). The present case showed that lung adenocarcinoma can rarely present with imaging findings that mimic fibrotic lesions of interstitial pneumonia. Lantuejoul et al. described a case of well-differentiated adenocarcinoma showing consolidation and honeycomb lung-like shadows on chest CT.1 They reported that carcinoma invasion accompanied by prominent stromal reactions—including fibrosis and inflammation—formed the rare radiological presentation of lung adenocarcinoma.1 Asymmetric lung involvement and symptoms of haemoptysis are clinical clues to the suspicion of lung neoplasm rather than fibrotic lung disease.2 Clinicians should be aware of this unusual presentation of lung adenocarcinoma.

High-resolution computed tomography at the diagnosis showing subpleural consolidation and reticular shadow in the left lung, accompanied by extensive emphysema (A). Most of the consolidation disappeared after the initiation of combination chemotherapy (B)

Atypical cells with a high nuclear–cytoplasmic ratio, nuclear hyperchromatism and distinct nucleoli, forming a cluster. Some of the atypical cells have abundant cytoplasmic mucin (*) and mitotic figure (arrow) (Papanicolaou staining)

AUTHOR CONTRIBUTION

Takuto Miyamura: investigation, writing–original draft, writing–review and editing, final approval of the manuscript. Yoshiaki Kinoshita: investigation, writing–review and editing and visualization, final approval of the manuscript. Hisako Kushima: writing–review and editing, final approval of the manuscript. Hiroshi Ishii: writing–review and editing, final approval of the manuscript.

ETHICS STATEMENT

The authors declare that appropriate written informed consent was obtained for the publication of this manuscript and accompanying images.