Baseline clinical and pathologic characteristics of all 55 patients with SBP who had cytogenetics by FISH available
| Characteristic . | High risk (n = 22; 40%) n (%) . | Standard risk (n = 33; 60%), n (%) . | P value . |
|---|---|---|---|
| Median age, y (range) | 62 (28-78) | 62 (29-83) | .72 |
| Male | 16 (73) | 22 (67) | 1.00 |
| White | 17 (77) | 31 (91) | .127 |
| Serum monoclonal protein detectable∗ | 21/21 (100) | 32/32 (100) | 1.00 |
| M spike (g/dL), median (range) | 0.75 (0.4-1.9) | 1 (0.4-1.8) | .436 |
| Abnormal FLC ratio† | 14 (64) | 18 (55) | .373 |
| Maximal SBP diameter of 5 cm or greater | 8/11 (73) | 8/24 (33) | .035 |
| Minimal marrow involvement present‡ | 20 (91) | 21 (64) | .029 |
| High-risk cytogenetic subtype§ | |||
| Del (17p) | 11 (50) | — | |
| Gain (1q) | 13 (59) | — | |
| t(4;14) | 2 (9) | — | |
| t(14;16) | 1 (5) | — | |
| t(14;20) | 0 | — |
| Characteristic . | High risk (n = 22; 40%) n (%) . | Standard risk (n = 33; 60%), n (%) . | P value . |
|---|---|---|---|
| Median age, y (range) | 62 (28-78) | 62 (29-83) | .72 |
| Male | 16 (73) | 22 (67) | 1.00 |
| White | 17 (77) | 31 (91) | .127 |
| Serum monoclonal protein detectable∗ | 21/21 (100) | 32/32 (100) | 1.00 |
| M spike (g/dL), median (range) | 0.75 (0.4-1.9) | 1 (0.4-1.8) | .436 |
| Abnormal FLC ratio† | 14 (64) | 18 (55) | .373 |
| Maximal SBP diameter of 5 cm or greater | 8/11 (73) | 8/24 (33) | .035 |
| Minimal marrow involvement present‡ | 20 (91) | 21 (64) | .029 |
| High-risk cytogenetic subtype§ | |||
| Del (17p) | 11 (50) | — | |
| Gain (1q) | 13 (59) | — | |
| t(4;14) | 2 (9) | — | |
| t(14;16) | 1 (5) | — | |
| t(14;20) | 0 | — |
The boldface P values are statistically significant at P < .05.
Detectable by either immunofixation or mass-fixation
Abnormal ratio defined as <0.26 or >1.65
Clonal plasma cells were considered positive if monoclonal plasma cells were detected by flow cytometry or immunohistochemistry on the bone marrow biopsy core or aspirate.
Some patients have multiple different high-risk cytogenetic subtypes and are counted in each category.