Investigating the solitary pulmonary nodule

Abstract

The presence of a solitary pulmonary nodule raises the suspicion of cancer and requires careful further investigation to determine whether it is malignant or benign #### Learning points An 81 year old man presented to the emergency department with a one week history of fever, cough, and right sided chest pain. He had had a myocardial infarction in 2004 but was otherwise well. He had a 50 pack-year smoking history. Clinical examination was unremarkable. His chest x ray showed a left mid-zone nodule (fig 1⇓). He was treated for a lower respiratory tract infection and referred to the lung cancer clinic with two week wait for an appointment. Fig 1 Patient’s chest x ray showing a left mid-zone nodule (arrow) The chest x ray is often the first investigation where a solitary pulmonary nodule is detected. A solitary pulmonary nodule is a rounded opacity, well or poorly defined, measuring up to 3 cm in diameter.1 They may represent early lung cancer, and prompt detection and treatment may improve clinical outcome. However, some nodules are benign, and determining which require further investigation may be difficult. Some common differential diagnoses are listed in box 1.2 3 #### Box 1 Common causes of a solitary pulmonary nodule23 ##### Malignant