Yttrium-90 ibritumomab tiuxetan as a single agent in patients with pretreated B-cell lymphoma: evaluation of the long-term outcome.
BACKGROUND
Based on historical data on the role of radioimmunotherapy (RIT) in pretreated non-Hodgkin lymphoma, we reviewed our hospital's clinical database.


METHODS
Between 2005 and 2008, 57 patients previously treated with at least 1 rituximab-containing chemotherapy were treated with Yttrium-90-labeled ibritumomab tiuxetan ((90)Y-IT). The median number of pretreatments was 3 (range, 1-9 pretreatments). A total of 46 patients had stage III/IV disease (31 with bone marrow involvement); 6 had bulky disease. According to histology, 53 were follicular lymphoma (FL), 2 were marginal zone lymphoma, and 2 were small lymphocytic lymphoma.


RESULTS
Overall response rate was 93% (53 of 57); complete response (CR) rate was 70% (40 of 57). Twenty-six of 40 patients (65%) who obtained a CR are in continuous CR (CCR) with a median follow-up of 20 months (range, 10-42 months); 4 of them still maintain their CCR after 36 months. All patients achieving a CCR had FL, and 21 of them with stage III/IV disease; 12 of 26 had been heavily pretreated (>or= 3 previous treatments), and 2 had had autologous stem cell transplantation. Toxicity was primarily hematologic and mostly transient; no grade 4 extrahematologic toxicity was observed.


CONCLUSIONS
This study confirms the safety and high efficacy of (90)Y-IT RIT in heavily pretreated FL patients, with the possibility of having a subset of long-term responders.
Zinzani
Pier Luigi
PL
Institute of Hematology and Medical Oncology L. e A. Seràgnoli, University of Bologna, Bologna, Italy. pierluigi.zinzani@unibo.it
Gandolfi
Letizia
L
Stefoni
Vittorio
V
Fanti
Stefano
S
Fina
Mariapaola
M
Pellegrini
Cinzia
C
Montini
Gian Carlo
GC
Derenzini
Enrico
E
Broccoli
Alessandro
A
Argnani
Lisa
L
Pileri
Stefano
S
Baccarani
Michele
M
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D016393:Lymphoma, B-Cell / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D016499:Radioimmunotherapy / Q000379:methods*; D012189:Retrospective Studies; D013995:Time; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000009:adverse effects / Q000627:therapeutic use*
D000911:Antibodies, Monoclonal; D015021:Yttrium Radioisotopes; C422802:ibritumomab tiuxetan