Their interstitial pneumonia had the following features: (a) it occurred predominantly in patients aged 60 years or older; (b) it was prevalent among patients with haematological malignancies, particularly non-Hodgkin's lymphoma; (c) in all patients G-CSF was given after anti-cancer agents with potential to affect the lungs; (d) at the onset, many patients had symptoms such as dyspnoea and fever; and (e) the leucocyte (neutrophil) count as well as lactate dehydrogenase (LDH) and C-reactive protein (CRP) levels were usually higher than normal at the onset. Here, CSF3 is linked to cancer.