Low-dose lung cancer screening: nodule measurement and management

Lung cancer screening by low-dose computed tomography (LDCT) is recommended for high-risk individuals by US guidelines, while lung cancer programs in Europe and Asia are being prepared. This review will mainly focus on two most recent concepts and discusses the latest developments. First, while a pulmonary nodule has an infinite number of diameters, it possesses only one volume. Traditionally, nodule size has been determined by diameter measurement, however semi-automated measurement of nodule volume is becoming increasingly available. Secondly, nodules that develop newly after baseline should distinguished from nodules already present at baseline. Until recently, new nodule management was mostly based on expert-opinion or data derived from baseline nodules.