FDG-PET in the assessment of patients with follicular lymphoma treated by ibritumomab tiuxetan Y 90: multicentric study.
BACKGROUND
The aim of this study is the 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) evaluation following radioimmunotherapy (RIT) with ibritumomab tiuxetan Y 90 in patients with non-Hodgkin's follicular lymphoma (FL).


METHODS
We retrospectively analyzed data from 59 relapsed or refractory FL patients treated with ibritumomab tiuxetan Y 90 in four different PET centers who had a PET scan carried out before and after RIT. Possible predictive factors of progression-free survival (PFS) were studied through univariate and multivariate analysis.


RESULTS
The post-RIT PET documented 45.8% complete responders (CR), 25.4% partial responders (PR) and 28.8% nonresponders [stable disease + progressive disease], with an overall survival of 71.2% (range 59.5%-90.9%). With a median follow-up period of 23 months, the univariate analysis documented a statistically significant relation between disease extent before RIT and response to treatment with respect to PFS (P = 0.015), while all the other prognostic factors showed no significant correlation. When carrying out the multivariate analysis, post-RIT PET resulted as the lonely independent predictor of PFS (P < 0.00001).


CONCLUSIONS
RIT is an effective therapy in FL patients, as confirmed in our study too. Disease extension before treatment and response to RIT, as assessed by FDG-PET, result as main predictors of PFS, with the post-RIT PET result being the only independent predictive factor.
Lopci
E
E
PET Unit, Nuclear Medicine Department, University Hospital S. Orsola-Malpighi, Bologna.
Santi
I
I
PET Unit, Nuclear Medicine Department, University Hospital S. Orsola-Malpighi, Bologna.
Derenzini
E
E
Department of Hematology, 'L. Seragnoli' Institution, University Hospital S. Orsola-Malpighi, Bologna.
Fonti
C
C
PET Unit, Nuclear Medicine Department, University Hospital S. Orsola-Malpighi, Bologna.
Savelli
G
G
Department of Nuclear Medicine, Spedali Civili, Brescia.
Bertagna
F
F
Department of Nuclear Medicine, Spedali Civili, Brescia.
Bellò
M
M
Department of Nuclear Medicine.
Botto
B
B
Department of Hematology, University Hospital San Giovanni Battista, Torino, Italy.
Huglo
D
D
Department of Nuclear Medicine, University Hospital Claude Huriez, Lille, France.
Morschhauser
F
F
Department of Nuclear Medicine, University Hospital Claude Huriez, Lille, France.
Zinzani
P
P
Department of Hematology, 'L. Seragnoli' Institution, University Hospital S. Orsola-Malpighi, Bologna.
Fanti
S
S
PET Unit, Nuclear Medicine Department, University Hospital S. Orsola-Malpighi, Bologna. Electronic address: stefano.fanti@aosp.bo.it.
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005500:Follow-Up Studies; D006801:Humans; D008224:Lymphoma, Follicular / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D049268:Positron-Emission Tomography; D011859:Radiography; D016499:Radioimmunotherapy; D019275:Radiopharmaceuticals / Q000627:therapeutic use; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000627:therapeutic use*
D000911:Antibodies, Monoclonal; D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes; D019788:Fluorodeoxyglucose F18; C422802:ibritumomab tiuxetan