Early 18F-FDG PET for prediction of prognosis in patients with diffuse large B-cell lymphoma: SUV-based assessment versus visual analysis.
The purpose of this study was to assess the prognostic value of early (18)F-FDG PET using standardized uptake value (SUV) compared with visual analysis in patients with diffuse large B-cell lymphoma (DLBCL).


METHODS
Ninety-two patients with newly diagnosed DLBCL underwent (18)F-FDG PET prospectively before and after 2 cycles of chemotherapy (at midtherapy). Maximum SUV (SUVmax) and mean SUV (SUVmean) normalized to body weight and body surface area, as well as tumor-to-normal ratios, were computed on the most intense uptake areas. The SUVs, tumor-to-normal ratios, and their changes over time were compared with visual analysis for predicting event-free survival (EFS) and overall survival, using receiver-operating-characteristic (ROC) analysis. Survival curves were estimated with Kaplan-Meier analysis and compared using the log-rank test.


RESULTS
With visual analysis, the accuracy of early PET to predict EFS was 65.2%. The 2-y estimate for EFS was 51% (95% confidence interval [CI], 34%-68%) in the PET-positive group compared with 79% (95% CI, 68%-90%) in the PET-negative group (P = 0.009). An optimal cutoff value of 65.7% SUVmax reduction from baseline to midtherapy obtained from ROC analysis yielded an accuracy of 76.1% to predict EFS. The 2-y estimate for EFS was 21% (95% CI, 0%-42%) in patients with SUVmax reduction <or= 65.7% compared with 79% (95% CI, 69%-88%) in those with reduction > 65.7% (P < 0.0001). Fourteen patients considered as positive on visual analysis could have been reclassified as good responders.


CONCLUSIONS
SUV-based assessment of therapeutic response during first-line chemotherapy improves the prognostic value of early (18)F-FDG PET compared with visual analysis in DLBCL.
Lin
Chieh
C
Department of Radiology, H. Mondor Hospital, AP-HP/Paris 12 University, Créteil, France.
Itti
Emmanuel
E
Haioun
Corinne
C
Petegnief
Yolande
Y
Luciani
Alain
A
Dupuis
Jehan
J
Paone
Gaetano
G
Talbot
Jean-Noël
JN
Rahmouni
Alain
A
Meignan
Michel
M
D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D005602:France / Q000453:epidemiology; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D016393:Lymphoma, B-Cell / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D049268:Positron-Emission Tomography / Q000706:statistics & numerical data*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016019:Survival Analysis; D015996:Survival Rate
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18