Analysis of response by characteristic in 142 consecutive patients receiving 131I-rituximab radioimmunotherapy
Characteristic . | No. of patients . | ORR (68%, n = 97) . | CR + CRu (50%, n = 71) . | ||||
---|---|---|---|---|---|---|---|
No. . | % . | P . | No. . | % . | P . | ||
Age, y | |||||||
< 60 | 60 | 49 | 81.7 | .004 | 38 | 63.3 | .011 |
≥ 60 | 82 | 48 | 58.5 | 33 | 40.2 | ||
Stage at entry | |||||||
I or II | 40 | 30 | 75.0 | .322 | 24 | 60.0 | .191 |
III or IV | 102 | 67 | 65.7 | 47 | 46.1 | ||
Serum LDH | |||||||
Normal | 82 | 61 | 74.4 | .164 | 44 | 53.7 | .349 |
High | 48 | 28 | 58.3 | 20 | 41.7 | ||
Unknown | 12 | 8 | 66.7 | 7 | 58.3 | ||
FLIPI | |||||||
0-1 | 37 | 29 | 78.4 | .227 | 26 | 70.3 | .021 |
2 | 39 | 28 | 71.8 | 19 | 48.7 | ||
≥ 3 | 29 | 19 | 65.5 | 13 | 44.8 | ||
NA | 36 | 20 | 55.6 | 12 | 33.3 | ||
Unknown | 1 | 1 | 100.0 | 1 | 100.0 | ||
Histology | |||||||
Follicular grade 1 | 39 | 31 | 79.5 | .012 | 23 | 59.0 | .105 |
Follicular grade 2 | 39 | 29 | 74.4 | 24 | 61.5 | ||
Follicular grade 3 | 16 | 8 | 50.0 | 7 | 43.8 | ||
Mantle | 8 | 2 | 25.0 | 1 | 12.5 | ||
MALT | 6 | 6 | 100.0 | 3 | 50.0 | ||
SLL | 21 | 12 | 57.1 | 7 | 33.3 | ||
Follicular unspecified/low grade | 13 | 9 | 69.2 | 6 | 46.2 | ||
Bone marrow involvement | |||||||
Yes | 46 | 33 | 71.7 | .699 | 24 | 52.2 | .857 |
No | 94 | 63 | 67.0 | 46 | 48.9 | ||
Unknown | 2 | 1 | 50.0 | 1 | 50.0 | ||
Prior chemotherapy | |||||||
1 | 87 | 26 | 29.9 | .0161 | 48 | 55.2 | .1451 |
2 | 31 | 18 | 58.1 | 14 | 45.2 | ||
≥ 3 | 24 | 11 | 45.8 | 8 | 33.3 | ||
Last chemo to I-131 RIT, mo | |||||||
≤ 6 | 41 | 20 | 48.8 | .0095 | 17 | 41.5 | .4510 |
> 6 | 90 | 66 | 73.3 | 45 | 50.0 | ||
Prior rituximab | |||||||
Yes | 80 | 50 | 62.5 | .098 | 30 | 37.5 | .001 |
No | 60 | 46 | 76.7 | 40 | 66.7 | ||
Unknown | 2 | 1 | 50.0 | 1 | 50.0 | ||
Prior DXRT | |||||||
Yes | 42 | 32 | 76.2 | .240 | 27 | 64.3 | .042 |
No | 99 | 65 | 65.7 | 44 | 44.4 | ||
Unknown | 1 | 0 | 0.0 | 0 | 0.0 | ||
Tumor diameter, cm | |||||||
> 5 | 28 | 16 | 57.1 | .913 | 10 | 35.7 | .109 |
≤ 5 | 105 | 77 | 73.3 | 58 | 55.2 | ||
Unknown | 9 | 4 | 44.4 | 3 | 33.3 | ||
B2 microglobulin | |||||||
Normal | 83 | 57 | 68.7 | .028 | 46 | 55.4 | .002 |
Elevated | 21 | 9 | 42.9 | 3 | 14.3 | ||
Unknown | 38 | 29 | 76.3 | 21 | 55.3 |
Characteristic . | No. of patients . | ORR (68%, n = 97) . | CR + CRu (50%, n = 71) . | ||||
---|---|---|---|---|---|---|---|
No. . | % . | P . | No. . | % . | P . | ||
Age, y | |||||||
< 60 | 60 | 49 | 81.7 | .004 | 38 | 63.3 | .011 |
≥ 60 | 82 | 48 | 58.5 | 33 | 40.2 | ||
Stage at entry | |||||||
I or II | 40 | 30 | 75.0 | .322 | 24 | 60.0 | .191 |
III or IV | 102 | 67 | 65.7 | 47 | 46.1 | ||
Serum LDH | |||||||
Normal | 82 | 61 | 74.4 | .164 | 44 | 53.7 | .349 |
High | 48 | 28 | 58.3 | 20 | 41.7 | ||
Unknown | 12 | 8 | 66.7 | 7 | 58.3 | ||
FLIPI | |||||||
0-1 | 37 | 29 | 78.4 | .227 | 26 | 70.3 | .021 |
2 | 39 | 28 | 71.8 | 19 | 48.7 | ||
≥ 3 | 29 | 19 | 65.5 | 13 | 44.8 | ||
NA | 36 | 20 | 55.6 | 12 | 33.3 | ||
Unknown | 1 | 1 | 100.0 | 1 | 100.0 | ||
Histology | |||||||
Follicular grade 1 | 39 | 31 | 79.5 | .012 | 23 | 59.0 | .105 |
Follicular grade 2 | 39 | 29 | 74.4 | 24 | 61.5 | ||
Follicular grade 3 | 16 | 8 | 50.0 | 7 | 43.8 | ||
Mantle | 8 | 2 | 25.0 | 1 | 12.5 | ||
MALT | 6 | 6 | 100.0 | 3 | 50.0 | ||
SLL | 21 | 12 | 57.1 | 7 | 33.3 | ||
Follicular unspecified/low grade | 13 | 9 | 69.2 | 6 | 46.2 | ||
Bone marrow involvement | |||||||
Yes | 46 | 33 | 71.7 | .699 | 24 | 52.2 | .857 |
No | 94 | 63 | 67.0 | 46 | 48.9 | ||
Unknown | 2 | 1 | 50.0 | 1 | 50.0 | ||
Prior chemotherapy | |||||||
1 | 87 | 26 | 29.9 | .0161 | 48 | 55.2 | .1451 |
2 | 31 | 18 | 58.1 | 14 | 45.2 | ||
≥ 3 | 24 | 11 | 45.8 | 8 | 33.3 | ||
Last chemo to I-131 RIT, mo | |||||||
≤ 6 | 41 | 20 | 48.8 | .0095 | 17 | 41.5 | .4510 |
> 6 | 90 | 66 | 73.3 | 45 | 50.0 | ||
Prior rituximab | |||||||
Yes | 80 | 50 | 62.5 | .098 | 30 | 37.5 | .001 |
No | 60 | 46 | 76.7 | 40 | 66.7 | ||
Unknown | 2 | 1 | 50.0 | 1 | 50.0 | ||
Prior DXRT | |||||||
Yes | 42 | 32 | 76.2 | .240 | 27 | 64.3 | .042 |
No | 99 | 65 | 65.7 | 44 | 44.4 | ||
Unknown | 1 | 0 | 0.0 | 0 | 0.0 | ||
Tumor diameter, cm | |||||||
> 5 | 28 | 16 | 57.1 | .913 | 10 | 35.7 | .109 |
≤ 5 | 105 | 77 | 73.3 | 58 | 55.2 | ||
Unknown | 9 | 4 | 44.4 | 3 | 33.3 | ||
B2 microglobulin | |||||||
Normal | 83 | 57 | 68.7 | .028 | 46 | 55.4 | .002 |
Elevated | 21 | 9 | 42.9 | 3 | 14.3 | ||
Unknown | 38 | 29 | 76.3 | 21 | 55.3 |
FLIPI indicates Follicular Lymphoma International Prognostic Index; MALT, mucosa-associated lymphoid tissue; ORR, overall response rate; CR, complete response; CRu, unconfirmed complete response; DXRT, external beam radiotherapy; and LDH, lactate dehydrogenase.
χ2 analysis for comparison of response rates among subgroups.