Analysis of Growth Curve Type in Pulmonary Nodules with
Different Characteristics

Background and objective Follow up by computed tomography (CT) and growth evaluation are routine methods for the differential diagnosis of indeterminate pulmonary nodules in clinical practice. Pulmonary nodules with diverse biological behaviors may show different growth patterns and velocities. The aim of this study is to identify the volume growth curve of both benign and malignant pulmonary nodules. This work also intends to determine these nodules' growth patterns and provide evidence for the establishment of a follow-up strategy. The CT data of 111 pulmonary nodules (54 solid, 57 subsolid) were retrospectively evaluated using 3D volumetric software. All of these nodules have been followed up at least twice. Of these nodules, 35 were confirmed as lung cancers, whereas 5 were confirmed as benign by pathology or histology. Moreover, 71 nodules showed no growth in more than 2 years. Stable nodules were defined as low-risk nodules, as confirmed by reevaluation from experts. On the basis of their densities and