Radiologic Predictors for Clinical Stage IA Lung Adenocarcinoma with Ground Glass Components: A Multi-Center Study of Long-Term Outcomes.
OBJECTIVE
This study was to define preoperative predictors from radiologic findings for the pathologic risk groups based on long-term surgical outcomes, in the aim to help guide individualized patient management.


METHODS
We retrospectively reviewed 321 consecutive patients with clinical stage IA lung adenocarcinoma with ground glass component on computed tomography (CT) scanning. Pathologic diagnosis for resection specimens was based on the 2011 IASLC/ATS/ERS classification of lung adenocarcinoma. Patients were classified into different pathologic risk grading groups based on their lymph node status, local regional recurrence and overall survival. Radiologic characteristics of the pulmonary nodules were re-evaluated by reconstructed three-dimension CT (3D-CT). Univariate and multivariate analysis identifies independent radiologic predictors from tumor diameter, total volume (TV), average CT value (AVG), and solid-to-tumor (S/T) ratio. Receiver operating characteristic curves (ROC) studies were carried out to determine the cutoff value(s) for the predictor(s). Univariate cox regression model was used to determine the clinical significance of the above findings.


RESULTS
A total of 321 patients with clinical stage IA lung adenocarcinoma with ground glass components were included in our study. Patients were classified into two pathologic low- and high- risk groups based on their distinguished surgical outcomes. A total of 134 patients fell into the low-risk group. Univariate and multivariate analyses identified AVG (HR: 32.210, 95% CI: 3.020-79.689, P<0.001) and S/T ratio (HR: 12.212, 95% CI: 5.441-27.408, P<0.001) as independent predictors for pathologic risk grading. ROC curves studies suggested the optimal cut-off values for AVG and S/T ratio were-198 (area under the curve [AUC] 0.921), 2.9 (AUC 0.996) and 54% (AUC 0.907), respectively. The tumor diameter and TV were excluded for the low AUCs (0.778 and 0.767). Both the cutoff values of AVG and S/T ratio were correlated with pathologic risk classification (p<0.001). Univariate Cox regression model identified clinical risk classification (RR: 3.011, 95%CI: 0.796-7.882, P = 0.095) as a good predictor for recurrence-free survival (RFS) in patients with clinical stage IA lung adenocarcinoma. Statistical significance of 5-year OS and RFS was noted among clinical low-, moderate- and high-risk groups (log-rank, p = 0.024 and 0.010).


CONCLUSIONS
The AVG and the S/T ratio by reconstructed 3D-CT are important preoperative radiologic predictors for pathologic risk grading. The two cutoff values of AVG and S/T ratio are recommended in decision-making for patients with clinical stage IA lung adenocarcinoma with ground glass components.
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Zhao
Z
Li
Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Bo
B
Ye
Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Shanghai Tongji University School of Medicine, Shanghai, China.
Minwei
M
Bao
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Binbin
B
Xu
Department of Dermatology, Huashan Hospital, Fudan University, Shanghai, China.
Qinyi
Q
Chen
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Sida
S
Liu
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Yudong
Y
Han
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Mingzhen
M
Peng
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Zhifeng
Z
Lin
Department of Thoracic Surgery, Guangzhou Medical University First Affiliated Hospital, Guangdong Province, China.
Jingpei
J
Li
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Wenzhuo
W
Zhu
Department of Thoracic Surgery, Shanghai General Hospital, Shanghai Jiaotong University School of medicine, Shanghai, China.
Qiang
Q
Lin
Department of Thoracic Surgery, Shanghai Chest Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.
Liwen
L
Xiong
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery; D049268:Positron-Emission Tomography; D011379:Prognosis; D012372:ROC Curve; D011859:Radiography; D012044:Regression Analysis; D012189:Retrospective Studies; D016019:Survival Analysis; D047368:Tumor Burden
D019788:Fluorodeoxyglucose F18