Repeated radioimmunotherapy with 131I-rituximab for patients with low-grade and aggressive relapsed or refractory B cell non-Hodgkin lymphoma.
OBJECTIVE
A single treatment of (131)I-rituximab in patients with B cell non-Hodgkin lymphoma (NHL) showed a modest rate of response (29 %) in a relatively short duration (median 2.9 months). On the basis of this result, we investigated whether repeated treatment with (131)I-rituximab could improve the response.


METHODS
Thirty-one patients with relapsed or refractory B cell NHL received unlabeled rituximab (70 mg) immediately prior to the administration of a therapeutic dose of (131)I-rituximab. The tumor response was evaluated 1 month later by contrast-enhanced (18)F-fluorodeoxyglucose positron emission tomography/computed tomography. Radioimmunotherapy (RIT) was repeated at 4-week intervals.


RESULTS
A total of 87 cycles of RIT were administered. Repeated RIT yielded twofold increases in response rate (68 %) and in median response duration (8.6 months). This protocol also induced a favorable response in patients with an aggressive histology compared to that induced by a single treatment (50 vs. 9 %, respectively, p = 0.063). The toxicities were principally hematologic with grade 4 thrombocytopenia occurring in 12 % and neutropenia occurring in 17 % of the 85 assessable cycles.


CONCLUSIONS
Compared to a single treatment, repeated RIT with (131)I-rituximab increased the response rate and duration for patients with relapsed or refractory B cell NHL, including those with an aggressive histology.
Division of Hematology/Oncology, Department of Internal Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, Seoul, Republic of Korea.
Hye Jin
HJ
Kang
Seung-Sook
SS
Lee
Byung Hyun
BH
Byun
Kyeong Min
KM
Kim
Ilhan
I
Lim
Chang Woon
CW
Choi
Cheolwon
C
Suh
Won Seog
WS
Kim
Seung-Hyun
SH
Nam
Soon Il
SI
Lee
Hyeon Seok
HS
Eom
Dong-Yeop
DY
Shin
Sang Moo
SM
Lim
D000328:Adult; D000368:Aged; D058846:Antibodies, Monoclonal, Murine-Derived / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000009:adverse effects / Q000627:therapeutic use*; D016393:Lymphoma, B-Cell / Q000401:mortality / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D016499:Radioimmunotherapy; D012008:Recurrence; D000069283:Rituximab
D058846:Antibodies, Monoclonal, Murine-Derived; D007457:Iodine Radioisotopes; D000069283:Rituximab; C507388:131I-rituximab