Dual-time point scanning of integrated FDG PET/CT for the evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT.
OBJECTIVE
To evaluate whether dual-time point scanning with integrated fluorine-18 fluorodeoxyglucose ((18)F-FDG) positron emission tomography and computed tomography (PET/CT) is useful for evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT.


METHODS
PET/CT data and pathological findings of 560 nodal stations in 129 patients with pathologically proven non-small cell lung cancer diagnosed as operable by contrast-enhanced CT were reviewed retrospectively. Standardized uptake values (SUVs) on early scans (SUVe) 1h, and on delayed scans (SUVd) 2h after FDG injection of each nodal station were measured. Retention index (RI) (%) was calculated by subtracting SUVe from SUVd and dividing by SUVe. Logistic regression analysis was performed with seven kinds of models, consisting of (1) SUVe, (2) SUVd, (3) RI, (4) SUVe and SUVd, (5) SUVe and RI, (6) SUVd and RI, and (7) SUVe, SUVd and RI. The seven derived models were compared by receiver-operating characteristic (ROC) analysis. k-Fold cross-validation was performed with k values of 5 and 10. p<0.05 was considered statistically significant.


RESULTS
Model (1) including the term of SUVe showed the largest area under the ROC curve among the seven models. The cut-off probability of metastasis of 3.5% with SUVe of 2.5 revealed a sensitivity of 78% and a specificity of 81% on ROC analysis, and approximately 60% and 80% on k-fold cross-validation.


CONCLUSIONS
Single scanning of PET/CT is sufficiently useful for evaluating mediastinal and hilar nodes for metastasis.
Kasai
Takami
T
Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8677, Japan. takaby@hotmail.com
Motoori
Ken
K
Horikoshi
Takuro
T
Uchiyama
Katsuhiro
K
Yasufuku
Kazuhiro
K
Takiguchi
Yuichi
Y
Takahashi
Fumiaki
F
Kuniyasu
Yoshio
Y
Ito
Hisao
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000556:secondary / Q000601:surgery; D003287:Contrast Media; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology*; D008297:Male; D008482:Mediastinum; D008875:Middle Aged; D016081:Moon; D049268:Positron-Emission Tomography / Q000379:methods; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult
D003287:Contrast Media; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18