[High-resolution CT findings of pulmonary atypical adenomatous hyperplasia of 5 mm or less in diameter].
OBJECTIVE
To clarify the high-resolution CT(HRCT) findings of pulmonary atypical adenomatous hyperplasia (AAH) of 5 mm or less in diameter.


METHODS
We evaluated the HRCT findings of 43 histopathologically confirmed AAH of 5 mm or less in diameter in 7 patients who underwent lobectomy for pulmonary adenocarcinoma. For comparison, we also examined the HRCT findings of 13 bronchioloalveolar carcinomas (BAC) of the same size from these patients.


RESULTS
We identified 36 of 43 AAH and all 13 BAC on HRCT performed with multidetector-row CT. Thirty-five AAH and 11 BAC showed ground-glass opacity without any high-attenuation component. Margins of 20 AAH were well defined, and 16 were ill defined. In BAC, 11 lesions demonstrated well-defined margins, with only 2 showing ill-defined margins.


CONCLUSIONS
Most AAH lesions of 5 mm or less in diameter are identified as ground-glass opacity on HRCT. Detection of minute ground-glass opacity is important in locating AAH on HRCT.
Ishikawa
Hiroyuki
H
Division of Radiation Oncology, Division of Cellular and Molecular Pathology, Graduate School of Medical and Dental Science, Niigata University.
Koizumi
Naoya
N
Naito
Makoto
M
Umezu
Hajime
H
Morita
Tetsurou
T
Nemoto
Takeo
T
Saito
Tomoo
T
Okuizumi
Mina
M
Sasai
Keisuke
K
D002282:Adenocarcinoma, Bronchiolo-Alveolar / Q000000981:diagnostic imaging* / Q000473:pathology; D018255:Adenomatosis, Pulmonary / Q000000981:diagnostic imaging* / Q000473:pathology*; D000368:Aged; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000000981:diagnostic imaging / Q000473:pathology; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011230:Precancerous Conditions / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement; D014057:Tomography, X-Ray Computed