Abstract

Paraffinoma of lung—localized lipoid pneumonia due to exogenous oil in the alveoli—must be remembered when considering unusual lung disorders, for this benign lesion can mimic lung cancer clinically, radiologically, during operation, and even on frozen section. Though usually caused by mineral oils taken as nose drops, sprays or laxatives, it can be caused by animal or vegetable oils. The lesion is essentially a macrophage response with phagocytosis of oil droplets. Symptoms can be minimal, simulating `virus pneumonia', local, with shortness of breath, cough, sputum, haemoptysis, and chest pain, or general. The history of oil ingestion, the finding of lipophages or free lipoid in the sputum, may suggest the diagnosis. Two cases treated 10 years earlier by lobectomy, one as lung cancer and the other as tuberculosis, and proven histologically to be paraffinoma of lung are described. Both patients had used oily nasal drops for chronic nasal sinusitis. Today they remain well.