New classification of small pulmonary nodules by margin characteristics on high-resolution CT.
OBJECTIVE
To analyze margin characteristics of pulmonary nodules on high-resolution CT (HRCT) in order to improve imaging diagnoses.


METHODS
HRCT images of 193 pulmonary nodules of less than 30 mm maximum diameter (113 primary cancers, 15 metastatic cancers, 55 inflammatory nodules, and 10 benign tumors) were reviewed and classified as to 6 types of margins: round, lobulated, densely spiculated, ragged, tentacle or polygonal and halo. The relationships of these imaging types to the diagnoses, the underlying pathological features, mainly those of tumor growth patterns in 93 neoplasms, and the pathological characteristics of 14 inflammatory nodules were investigated.


RESULTS
Eighty-two percent of the lobulated, 97% of the densely spiculated, 93% of the ragged and 100% of the halo nodules were malignant. Eighty percent of the tentacle or polygonal nodules were inflammatory and 66% of the round ones were benign. The 6 types differed statistically as to the nature of the benignity/malignancy (p<0.001). Pathologically, in case of neoplasms, most of the 6 types had a relationship to a particular tumor growth pattern.


CONCLUSIONS
This HRCT classification method is useful for determining the nature of small pulmonary nodules and reflects the underlying pathological characteristics.
Furuya
K
K
Department of Radiology, National Kyushu Cancer Center, Fukuoka, Japan.
Murayama
S
S
Soeda
H
H
Murakami
J
J
Ichinose
Y
Y
Yabuuchi
H
H
Katsuda
Y
Y
Koga
M
M
Masuda
K
K
D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018287:Carcinoma, Large Cell / Q000000981:diagnostic imaging / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000000981:diagnostic imaging / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000145:classification / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D003074:Solitary Pulmonary Nodule / Q000145:classification* / Q000000981:diagnostic imaging / Q000473:pathology*; D014057:Tomography, X-Ray Computed