Prediction of occult lymph node metastasis by metabolic parameters in patients with clinically N0 esophageal squamous cell carcinoma.
The aim of this study was to investigate the value of (18)F-FDG parameters of the primary tumor in predicting occult lymph node metastasis in patients with clinically N0 esophageal squamous cell carcinoma.


METHODS
The study comprised 143 consecutive patients (mean age ± SD, 63.9 ± 8.6 y; range, 31.8-81.2 y) from May 2003 to January 2010 who had clinically N0 esophageal squamous cell carcinoma based on preoperative imaging studies including chest CT, (18)F-FDG PET/CT, and endoscopic ultrasound. We measured maximum standardized uptake value (SUV max), mean SUV (SUV mean), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) of the primary tumor and analyzed the relationship between clinicopathologic variables including PET parameters and occult lymph node metastasis using a logistic regression model.


RESULTS
Univariate analysis indicated that clinical T classification, SUV max, SUV mean, MTV, TLG, and longitudinal diameter of tumor were significant risk factors associated with occult lymph node metastasis. Optimal thresholds were cT2-4, SUV max ≥ 4.8, SUV mean ≥ 3.2, MTV ≥ 5.5 cm(3), TLG ≥ 220, and diameter ≥ 3.8 cm. After multivariate analysis, the logistic regression model revealed that clinical T classification (hazard ratio [HR], 4.6; 95% confidence interval [CI], 1.7-12.4; P = 0.003) and SUV max (HR, 3.5; 95% CI, 1.3-9.2; P = 0.012) were independent risk factors. The combination of SUV max and clinical T classification (HR, 13.2; 95% CI, 5.4-31.9; P < 0.001) was a significantly better powerful risk factor for occult lymph node metastasis than SUV max or clinical T classification alone. Sensitivity, specificity, positive predictive value, and negative predictive value of the combination of clinical T classification and SUV max were 73.0%, 81.5%, 60.0%, and 89.7%, respectively.


CONCLUSIONS
SUV max, combined with clinical T classification, may be useful for predicting occult lymph node metastasis in patients with clinically N0 squamous cell carcinoma of the esophagus.
Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea; and.
Seung Hwan
SH
Moon
Ho Seong
HS
Kim
Seung Hyup
SH
Hyun
Yong Soo
YS
Choi
Jae Ill
JI
Zo
Young Mog
YM
Shim
Kyung-Han
KH
Lee
Byung-Tae
BT
Kim
Joon Young
JY
Choi
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000473:pathology*; D004724:Endoscopy; D004938:Esophageal Neoplasms / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006019:Glycolysis; D006801:Humans; D016015:Logistic Models; D008207:Lymphatic Metastasis / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012307:Risk Factors; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography
D001786:Blood Glucose; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
18F-FDG; PET/CT; SUVmax; esophageal cancer; lymph node; occult metastasis