Vanishing lung mass in a patient with asthma.

Allergic bronchopulmonary aspergillosis (ABPA) is a common but frequently misdiagnosed clinical condition. It is usually diagnosed in patients with a long standing history of asthma. Patients with ABPA can have diverse radiological manifestations. Very rarely, lung masses have been reported. We hereby report a case of ABPA in whom a large symptomatic lung mass was the presenting manifestation leading to consideration of lung cancer as a differential diagnosis. The establishment of ABPA as the underlying diagnosis led to conservative medical treatment which was followed by complete resolution of the mass like opacity. The present case highlights that ABPA should be considered as a differential diagnosis whenever encountering a patient with lung mass and history of asthma.