Diagnostic and prognostic impact of 18F-FDG PET/CT in follicular lymphoma.
OBJECTIVE
The aim of this study was to assess the usefulness of positron emission tomography/computed tomography in staging, prognosis evaluation and restaging of patients with follicular lymphoma.


METHODS
A retrospective study was performed on 45 patients with untreated biopsy-proven follicular lymphoma who underwent 18F-fluorodeoxyglucose PET/CT (FDG PET/CT) and CT before and after chemoimmunotherapy induction treatment (rituximab combined with cyclophosphamide, doxorubicin, vincristine and prednisone).


RESULTS
PET/CT detected more nodal (+51%) and extranodal (+89%) lesions than CT. PET/CT modified Ann Arbor staging in eight patients (18%). Five patients (11%) initially considered as being early stage (I/II) were eventually treated as advanced stage (III/IV). In this study, an initial PET/CT prognostic score was significantly more accurate than the Follicular Lymphoma International Prognostic Index score in identifying patients with poor prognosis (i.e. patients with incomplete therapeutic response or early relapse). The accuracy of PET/CT for therapeutic response assessment was higher than that of CT (0.97 vs 0.64), especially due to its ability to identify inactive residual masses. In addition, post-treatment PET/CT was able to predict patients' outcomes. The median progression-free survival was 48 months in the PET/CT-negative group as compared with 17.2 months for the group with residual uptake (p<10(-4)).


CONCLUSIONS
FDG PET/CT is useful for staging and assessing the prognosis and therapeutic response of patients with follicular lymphoma.
Le Dortz
Ludovic
L
Nuclear Medicine Department, Eugène Marquis Anticancer Centre, Rennes, France.
De Guibert
Sophie
S
Bayat
Sahar
S
Devillers
Anne
A
Houot
Roch
R
Rolland
Yan
Y
Cuggia
Marc
M
Le Jeune
Florence
F
Bahri
Haïfa
H
Barge
Marie-Luce
ML
Lamy
Thierry
T
Garin
Etienne
E
D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D008224:Lymphoma, Follicular / Q000175:diagnosis* / Q000188:drug therapy*; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
D007155:Immunologic Factors; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18