18F-FDG-PET in patients with malignant lymphoma having long-term follow-up: staging and restaging, and evaluation of treatment response and recurrence.
OBJECTIVE
The aim of this study was to evaluate the diagnostic accuracy of positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (18F-FDG) for staging/restaging, evaluating the treatment response, and screening of recurrence in patients with malignant lymphoma (ML) during long-term follow-up, and to compare that with computer tomography (CT)/magnetic resonance imaging (MRI).


METHODS
The study was conducted in 59 ML patients who underwent whole-body 18F-FDG-PET examinations three times or more from October 1998 to August 2006. The location of the lesions in the patients with positive findings on 18F-FDG-PET and/or the corresponding CT/MRI was classified into supradiaphragmatic (n = 10), infradiaphragmatic (n = 7), and extranodal sites (n = 20), and the findings were compared on a site basis according to the gold standard, which consisted of all clinical information available, including follow-up results.


RESULTS
A total of 156 18F-FDG-PET examinations for which the corresponding CT/MRI images were also available were evaluated, and a total of 305 sites showed positive findings on 18F-FDG-PET and/or CT/MRI. Concordant positive findings were obtained in 76% for staging/restaging, 34% for evaluation of the treatment response, and 50% for screening of recurrence. The accuracy of 18F-FDG-PET versus CT/MRI was 92% versus 84% (P = 0.06) for staging/restaging, 84% versus 50% (P < 0.05) for the evaluation of the treatment response, and 83% versus 72% (P = 0.21) for the screening of recurrence. At pathologic sites with discrepant findings between 18F-FDG-PET and CT/MRI (n = 122), the frequency of accurate diagnosis by 18F-FDG-PET (76%) was higher than that by CT/MRI (24%), especially for the evaluation of the treatment response.


CONCLUSIONS
18F-FDG-PET is expected to play a significant role in the management of ML patients even after effective treatment is initiated.
Isohashi
Kayako
K
Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Tatsumi
Mitsuaki
M
Higuchi
Ichiro
I
Inoue
Atsuo
A
Nakajo
Kazuya
K
Ishikawa
Jun
J
Shimosegawa
Eku
E
Kanakura
Yuzuru
Y
Nakamura
Hironobu
H
Hatazawa
Jun
J
D000293:Adolescent; D000328:Adult; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000628:therapy*; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000517:prevention & control*; D009367:Neoplasm Staging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055815:Young Adult
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18