Initial findings and progression of lung adenocarcinoma on serial computed tomography scans.
OBJECTIVE
To study the initial findings of lung adenocarcinoma revealed by computed tomography (CT) scanning and observe tumor progression and elucidate appropriate follow-up schedule of tumor diagnosis via CT findings of suspected lung adenocarcinoma.


METHODS
We studied 59 patients who had undergone CT scanning twice or more at intervals of 3 months or longer before surgery. We evaluated the initial CT findings as well as all subsequent changes. The rate of tumor growth was estimated by tumor volume doubling time, using the original method of Schwartz. The histological classifications were evaluated according to the criteria of Noguchi et al (Cancer 1995;75:2844-2852).


RESULTS
The initial appearances of lung adenocarcinoma were divided into 4 types: (1) ground-glass opacity-like lesions, (2) bubble-like appearance, (3) small nodules, and (4) scar-like lesions. Ground-glass opacity-like lesions tended to increase in size over the years, with solid parts appearing in some lesions during follow-up examinations. Bubble-like appearance displayed characteristic CT findings and tended to increase over the years from the time of initial diagnosis, and we therefore tended to consider them as old inflammatory lesions. Small nodules tended to increase in size over the months more rapidly than in other types. Scar-like lesions tended to exist mainly in the lungs already damaged by lung fibrosis and/or emphysema and therefore were difficult to detect on initial CT scans.


CONCLUSIONS
We categorized 4 types of initial findings of lung adenocarcinomas detected by CT. We determined that each type of lesion had its own unique characteristic growth patterns and required varying follow-up periods.
Saito
Haruhiro
H
Department of Thoracic Oncology, Kanagawa Cancer Center, Yokohama, Japan. saito-h@kcch.jp
Yamada
Kouzo
K
Hamanaka
Nobuyuki
N
Oshita
Fumihiro
F
Ito
Hiroyuki
H
Nakayama
Haruhiko
H
Yokose
Tomoyuki
T
Kameda
Yoichi
Y
Noda
Kazumasa
K
D000230:Adenocarcinoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D000328:Adult; D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*