Baseline group characteristics
| Variable . | Total (n = 1347) . | BP (n = 813 [60.4%]) . | CP (n = 534 [39.6%]) . | P . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| n/N . | % . | Median (IQR) . | n/N . | % . | Median (IQR) . | n/N . | % . | Median (IQR) . | ||
| Age at diagnosis, y | 62.9 (55.8-69.6) | 62.9 (56.3-69.4) | 62.4 (55.3-69.8) | .48 | ||||||
| Age at relapse, y | 65.2 (58.2-72.1) | 65.5 (58.9-71.9) | 64.5 (57.3-72.8) | .42 | ||||||
| Year of diagnosis before 2013 | 959/1347 | 71.2 | 570/813 | 70.1 | 389/534 | 73.9 | .3 | |||
| Time from diagnosis to first relapse, mo | 22.8 (12.0-37.3) | 23.7 (14.7-37.1) | 20.8 (9.0-37.6) | .001 | ||||||
| Male sex | 803/1347 | 59.6 | 478/813 | 58.8 | 325/534 | 60.9 | .45 | |||
| Bone marrow plasma cells, % | 50 (30-73) | 50 (30-75) | 50 (25-70) | .12 | ||||||
| Plasma cells in S-phase ≥2% | 160/697 | 23.0 | 83/418 | 19.9 | 77/279 | 27.6 | .02 | |||
| Abnormal cytogenetics | 281/1154 | 0.2 | 158/704 | 22.4 | 123/450 | 27.3 | .06 | |||
| High-risk FISH | 237/1034 | 22.9 | 128/651 | 19.7 | 109/383 | 28.5 | .001 | |||
| IgG isotype | 732/1347 | 54.3 | 451/813 | 55.5 | 281/534 | 52.6 | .30 | |||
| Non-secretory | 47/1347 | 3.5 | 17/813 | 2.1 | 30/534 | 5.6 | <.001 | |||
| Involved kappa light chain | 793/1347 | 58.9 | 491/813 | 60.4 | 302/534 | 56.6 | .16 | |||
| Lytic lesions | 962/1347 | 71.4 | 565/792 | 71.3 | 397/525 | 75.6 | .087 | |||
| EMD at diagnosis | 179/1313 | 13.6 | 80/789 | 10.1 | 99/524 | 18.9 | <.001 | |||
| Anemia (↓ in hemoglobin ≥2 g/dL or to ≤10 g/dL) | 324/1298 | 25.0 | 161/794 | 20.3 | 163/504 | 32.3 | .8 | |||
| Platelet count × 109/L | 209 (158.0-262) | 208 (159-162) | 2010 (155-165) | .92 | ||||||
| Hypercalcemia ≥11.5 mg/dL | 140/1216 | 11.5 | 74/739 | 10.0 | 66/477 | 13.8 | .04 | |||
| Renal insufficiency (↑ serum creatinine ≥2g/dL) | 192/1257 | 15.3 | 115/763 | 15.1 | 77/494 | 15.6 | .8 | |||
| Serum albumin, g/dL | 3.6 (3.3-3.9) | 3.6 (3.3-3.9) | 3.5 (3.2-3.8) | .08 | ||||||
| Serum β2 microglobulin, mg/L | 4.1 (2.8-6.7) | 4.0 (2.8-6.6) | 4.2 (2.8-6.8) | .62 | ||||||
| Elevated lactate dehydrogenase | 176/926 | 19.0 | 97/576 | 16.8 | 79/350 | 22.6 | .03 | |||
| Serum M spike, g/dL | 2.6 (0.8-4.0) | 2.7 (0.8-4.1) | 2.4 (0.7-3.9) | .16 | ||||||
| ISS stage | ||||||||||
| I | 318/1162 | 27.4 | 195/711 | 27.4 | 123/451 | 27.3 | .69 | |||
| II | 445/1162 | 38.3 | 280/711 | 39.4 | 165/451 | 36.6 | .18 | |||
| III | 399/1162 | 34.3 | 236/711 | 33.2 | 163/451 | 36.1 | .56 | |||
| Variable . | Total (n = 1347) . | BP (n = 813 [60.4%]) . | CP (n = 534 [39.6%]) . | P . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| n/N . | % . | Median (IQR) . | n/N . | % . | Median (IQR) . | n/N . | % . | Median (IQR) . | ||
| Age at diagnosis, y | 62.9 (55.8-69.6) | 62.9 (56.3-69.4) | 62.4 (55.3-69.8) | .48 | ||||||
| Age at relapse, y | 65.2 (58.2-72.1) | 65.5 (58.9-71.9) | 64.5 (57.3-72.8) | .42 | ||||||
| Year of diagnosis before 2013 | 959/1347 | 71.2 | 570/813 | 70.1 | 389/534 | 73.9 | .3 | |||
| Time from diagnosis to first relapse, mo | 22.8 (12.0-37.3) | 23.7 (14.7-37.1) | 20.8 (9.0-37.6) | .001 | ||||||
| Male sex | 803/1347 | 59.6 | 478/813 | 58.8 | 325/534 | 60.9 | .45 | |||
| Bone marrow plasma cells, % | 50 (30-73) | 50 (30-75) | 50 (25-70) | .12 | ||||||
| Plasma cells in S-phase ≥2% | 160/697 | 23.0 | 83/418 | 19.9 | 77/279 | 27.6 | .02 | |||
| Abnormal cytogenetics | 281/1154 | 0.2 | 158/704 | 22.4 | 123/450 | 27.3 | .06 | |||
| High-risk FISH | 237/1034 | 22.9 | 128/651 | 19.7 | 109/383 | 28.5 | .001 | |||
| IgG isotype | 732/1347 | 54.3 | 451/813 | 55.5 | 281/534 | 52.6 | .30 | |||
| Non-secretory | 47/1347 | 3.5 | 17/813 | 2.1 | 30/534 | 5.6 | <.001 | |||
| Involved kappa light chain | 793/1347 | 58.9 | 491/813 | 60.4 | 302/534 | 56.6 | .16 | |||
| Lytic lesions | 962/1347 | 71.4 | 565/792 | 71.3 | 397/525 | 75.6 | .087 | |||
| EMD at diagnosis | 179/1313 | 13.6 | 80/789 | 10.1 | 99/524 | 18.9 | <.001 | |||
| Anemia (↓ in hemoglobin ≥2 g/dL or to ≤10 g/dL) | 324/1298 | 25.0 | 161/794 | 20.3 | 163/504 | 32.3 | .8 | |||
| Platelet count × 109/L | 209 (158.0-262) | 208 (159-162) | 2010 (155-165) | .92 | ||||||
| Hypercalcemia ≥11.5 mg/dL | 140/1216 | 11.5 | 74/739 | 10.0 | 66/477 | 13.8 | .04 | |||
| Renal insufficiency (↑ serum creatinine ≥2g/dL) | 192/1257 | 15.3 | 115/763 | 15.1 | 77/494 | 15.6 | .8 | |||
| Serum albumin, g/dL | 3.6 (3.3-3.9) | 3.6 (3.3-3.9) | 3.5 (3.2-3.8) | .08 | ||||||
| Serum β2 microglobulin, mg/L | 4.1 (2.8-6.7) | 4.0 (2.8-6.6) | 4.2 (2.8-6.8) | .62 | ||||||
| Elevated lactate dehydrogenase | 176/926 | 19.0 | 97/576 | 16.8 | 79/350 | 22.6 | .03 | |||
| Serum M spike, g/dL | 2.6 (0.8-4.0) | 2.7 (0.8-4.1) | 2.4 (0.7-3.9) | .16 | ||||||
| ISS stage | ||||||||||
| I | 318/1162 | 27.4 | 195/711 | 27.4 | 123/451 | 27.3 | .69 | |||
| II | 445/1162 | 38.3 | 280/711 | 39.4 | 165/451 | 36.6 | .18 | |||
| III | 399/1162 | 34.3 | 236/711 | 33.2 | 163/451 | 36.1 | .56 | |||
IgG, immunoglobulin G; IQR, interquartile range; M spike, monoclonal protein spike; n/N, number of patients with positive result/number of patients with available data.