morphologic imaging findings that are suggestive of a malignant solitary pulmonary nodule
Size greater than 1 cm is more suggestive of malignancy. Lobulated or spiculated margins with distortion of adjacent vessels and lung architecture can also be associated with malignancy, although a lobulated or spiculated margin is seen in 25% and 10% of benign nodules. The “corona radiata” sign consists of very fine linear strands extending outward from a nodule and is strongly suggestive of malignancy. Partially solid nodules (i.e., nodules composed of ground glass and solid components) tend to be malignant and are most often due to lung adenocarcinoma. Internal inhomogeneity, particularly caused by cystic/bubbly lucencies or pseudocavitation, strongly suggests malignancy, most often from adenocarcinoma in situ (AIS) or minimally invasive adenocarcinoma (MIA). Cavitary nodules with maximal wall thickness greater than 15 mm and wall irregularity tend to be malignant, whereas nodules with wall thickness 4 mm or less tend to be benign.
