Role of [18F]fluorodeoxyglucose positron emission tomography scan in the follow-up of lymphoma.
OBJECTIVE
In lymphoma, [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) is routinely used for initial staging, early evaluation of treatment response, and identification of disease relapse. However, there are no prospective studies investigating the value of serial FDG-PET over time in patients in complete remission.


METHODS
All patients with lymphoma who achieved the first complete remission were prospectively enrolled onto the study and scheduled for serial FDG-PET scans at 6, 12, 18, and 24 months; further scans were then carried out on an annual basis. Overall, the population included 421 patients (160 patients with Hodgkin's lymphoma [HL], 183 patients with aggressive non-Hodgkin's lymphoma [NHL], and 78 patients with indolent follicular NHL). All patients had a regular follow-up evaluation, including complete clinical and laboratory evaluation, and final assessment of any suspect FDG-PET findings using other imaging procedures (computed tomography [CT] scan) and/or biopsy and/or clinical evolution. FDG-PET findings were reported as positive for relapse, inconclusive (when equivocal), or negative for relapse.


RESULTS
PET enabled documentation of lymphoma relapse in 41 cases at 6 months, in 30 cases at 12 months, in 26 cases at 18 months, in 10 cases at 24 months, and in 11 cases at more than 36 months. All 36 patients with inconclusive positive PET underwent biopsy; only 12 (33%) of 36 patients had a concomitant suggestion of positivity on CT. A lymphoma relapse was diagnosed in 24 (66%) of 36 patients.


CONCLUSIONS
Our results confirm FDG-PET as a valid tool for follow-up of patients with HL and NHL. In patients with inconclusive positive results, histologic confirmation plays an important role in identifying true relapse.
Zinzani
Pier Luigi
PL
Institute of Hematology and Oncology L & A Seràgnoli, University of Bologna, Bologna, Italy. plzinzo@med.unibo.it
Stefoni
Vittorio
V
Tani
Monica
M
Fanti
Stefano
S
Musuraca
Gerardo
G
Castellucci
Paolo
P
Marchi
Enrica
E
Fina
Mariapaola
M
Ambrosini
Valentina
V
Pellegrini
Cinzia
C
Alinari
Lapo
L
Derenzini
Enrico
E
Montini
Giancarlo
G
Broccoli
Alessandro
A
Bacci
Francesco
F
Pileri
Stefano
S
Baccarani
Michele
M
D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008223:Lymphoma / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000473:pathology; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012008:Recurrence
D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18