Introduction
Materials and methods
Study design
FDG-PET/CT imaging and evaluation
Freelite TM and HevyliteTM assays
Tumor biopsies
Circulating tumor DNA
Mutation calling and LymphGen classification
Statistical analysis
Results
Patient, lymphoma, and treatment characteristics
No IgM gammopathya | IgM gammopathya | pb | Totala | |
---|---|---|---|---|
Number | 89 | 19 | 108 | |
Age (years), median (range) | 56 (25–79) | 63 (42–79) | 0.065c | 58 (25–79) |
Male patients | 48 (54%) | 9 (47%) | 0.623 | 57 (53%) |
Clinical risk factors | ||||
Age > 60 years | 42 (47%) | 11 (58%) | 0.455 | 53 (49%) |
ECOG performance status ≥ 2 | 9 (10%) | 5 (26%) | 0.069 | 14 (13%) |
Ann Arbor stage III or IV | 45 (51%) | 14 (74%) | 0.079 | 59 (55%) |
≥ 2 extranodal manifestations | 22 (25%) | 9 (47%) | 0.056 | 31 (29%) |
Serum lactate dehydrogenase > upper limit of normal | 44 (49%) | 14 (74%) | 0.076 | 58 (54%) |
B symptoms | 23 (26%) | 8 (42%) | 0.171 | 31 (29%) |
International Prognostic Index | ||||
Low risk | 44 (49%) | 3 (16%) | 0.025d | 47 (43%) |
Low-intermediate risk | 16 (18%) | 3 (16%) | 19 (18%) | |
High-intermediate risk | 17 (19%) | 8 (42%) | 25 (23%) | |
High risk | 12 (14%) | 5 (26%) | 17 (16%) | |
Serum abnormalities | ||||
Elevated immunoglobulin free light chain concentration | 29 (33%) | 10 (53%) | 0.118 | 39 (36%) |
Monoclonal immunoglobulin free light chain | 19 (21%) | 4 (21%) | 1.000 | 23 (21%) |
No IgM gammopathya | IgM gammopathya | pb | Totala | |
---|---|---|---|---|
Histomorphology | ||||
Diffuse large B-cell lymphoma, not otherwise specified | 89 | 19 | 108 | |
Centroblastic variant | 41 (46%) | 6 (32%) | 0.700c | 47 (43%) |
Immunoblastic variant | 3 (3%) | 1 (5%) | 4 (4%) | |
Anaplastic variant | 3 (3%) | 1 (5%) | 4 (4%) | |
Variant not specified | 42 (48%) | 11 (58%) | 53 (49%) | |
Gene expression (cell-of-origin classification) | ||||
Non-germinal center B-cell-like (protein expression, Hans classifier) | 27/49 (55%) | 6/11 (55%) | 1.000 | 33/60 (55%) |
Activated B-cell-like (mRNA expression, HTG EdgeSeq Assay) | 21/37 (57%) | 4/7 (57%) | 1.000 | 25/44 (57%) |
Translocations | ||||
MYC | 6/50 (12%) | 1/10 (10%) | 1.000 | 7/60 (12%) |
MYC and BCL2 and/or BCL6 (“double hit”) | 4/50 (8%) | 1/10 (10%) | 1.000 | 5/60 (8%) |
Tumor burden | ||||
Total metabolic tumor volume above prognostic threshold (328 cm3)d | 25/77 (32%) | 9/17 (53%) | 0.162 | 34/94 (36%) |
Total metabolic tumor volume, cm3, median (range) | 89 (3–3968) | 411 (9–2693) | 0.124e | 123 (3–3968) |
No IgM gammopathya | IgM gammopathya | p | Totala | |
---|---|---|---|---|
Number | 89 | 19 | 108 | |
Response after 2 cycles R-CHOP | ||||
Interim PET positive (poor treatment response) | 8 (9%) | 1 (5%) | 1.000b | 9 (8%) |
Treatment allocation | ||||
6 × R-CHOP | 12 (13%)c | 3 (16%) | 0.970d | 15 (14%) |
6 × R-CHOP + 2 × R | 69 (78%)c | 15 (79%) | 84 (78%) | |
8 × R-CHOP | 3 (3%) | 0 (0%) | 3 (3%) | |
2 × R-CHOP + 6 × Burkitt’s lymphoma protocol | 5 (6%)e | 1(5%) | 6 (5%) | |
End-of-treatment remission status | ||||
Complete remission | 56 (63%) | 13 (68%) | 0.019f | 69 (64%) |
Partial remission | 25 (28%) | 2 (11%) | 27 (25%) | |
Stable disease | 0 (0%) | 1 (5%) | 1 (1%) | |
Progressive disease | 1 (1%) | 2 (11%) | 3 (3%) | |
Premature treatment termination | 7 (8%) | 1 (5%) | 8 (7%) | |
Long-term outcomeg | ||||
Freedom from progression at 3 years | 85.9% ± 3.8% | 52.6% ± 11.5% | <0.001 | 80.0% ± 3.9% |
Interim PET negative | 89.8% ± 3.4% | 55.6% ± 11.7% | <0.001 | 83.5% ± 3.8% |
Interim PET positive | 41.7% ± 20.5% | 0.0% | 0.548 | 35.6% ± 18.6% |
Overall survival at 3 years | 93.0% ± 2.8% | 62.7% ± 11.2% | <0.001 | 87.5% ± 3.3% |
Interim PET negative | 94.9% ± 2.5% | 66.2 ± 11.3% | <0.001 | 89.5% ± 3.1% |
Interim PET positive | 70.0% ± 18.2% | 0.0% | 0.113 | 61.0% ± 18.1% |
Association of IgM monoclonal gammopathy with disease features
Treatment results in relation to interim PET and IgM monoclonal gammopathy
Univariable and multivariable Cox regression analyses
Hazard ratio | 95% confidence interval | p | |
---|---|---|---|
Time to progression (23 events) | |||
IgM monoclonal gammopathy | 4.442 | 1.947–10.270 | <0.001 |
Interim PET positive | 6.556 | 2.556–16.814 | <0.001 |
Total metabolic tumor volume above prognostic threshold (328 cm2)a | 3.260 | 1.387–7.665 | 0.007 |
IPI high-intermediate or high riskb | 1.816 | 0.801–4.116 | 0.153 |
IPI high riskc | 1.605 | 0.594–4.338 | 0.351 |
Age > 60 years | 0.947 | 0.418–2.146 | 0.895 |
B symptoms | 1.806 | 0.780–4.182 | 0.167 |
Elevated immunoglobulin free light chain concentration | 2.126 | 0.933–4.842 | 0.072 |
Monoclonal immunoglobulin free light chain | 1.594 | 0.656–3.877 | 0.303 |
Overall survival (15 events) | |||
IgM monoclonal gammopathy | 6.619 | 2.373–18.458 | <0.001 |
Interim PET positive | 5.691 | 1.798–18.014 | 0.011 |
Total metabolic tumor volume above prognostic threshold (328 cm2)a | 4.361 | 1.478–12.868 | 0.008 |
IPI high-intermediate or high riskb | 1.821 | 0.660–5.024 | 0.247 |
IPI high riskc | 2.841 | 0.965–8.361 | 0.058 |
Age > 60 years | 1.609 | 0.573–4.523 | 0.367 |
B symptoms | 2.443 | 0.883–6.760 | 0.085 |
Elevated immunoglobulin free light chain concentration | 1.774 | 0.639–4.928 | 0.271 |
Monoclonal immunoglobulin free light chain | 1.843 | 0.630–5.396 | 0.265 |
Hazard ratioa | 95% confidence interval | p | |
---|---|---|---|
Time to progression (22 events) | |||
IgM monoclonal gammopathy | 5.443 | 2.209–13.407 | <0.001 |
Interim PET positive | 6.073 | 2.084–17.698 | <0.001 |
Total metabolic tumor volume above prognostic threshold (328 cm2)b | 1.856 | 0.730–4.718 | 0.194 |
Overall survival (15 events) | |||
IgM monoclonal gammopathy | 8.154 | 2.643–25.155 | <0.001 |
Interim PET positive | 5.478 | 1.431–20.984 | 0.013 |
Total metabolic tumor volume above prognostic threshold (328 cm2)b | 2.520 | 0.782–8.122 | 0.122 |