Table 1.
Effects of preparative and cell-specific features on differences in plasma cell numbers
| Variables | hBMPC versus sBMPC, difference, % | sBMPC versus fBMPC, difference, % | |||
|---|---|---|---|---|---|
| No. | Median (IQR) | P value | Median (IQR) | P value | |
| Referring institution | |||||
| MUV 1 | 76 | 24 (9.5–46) | 0.312 | 2 (0.4–8) | 0.526 |
| MUV 2 | 61 | 18 (9–40) | 1.6 (0.4–4) | ||
| MUV 3 | 34 | 14.3 (6–22) | 1.3 (0.5–3.7) | ||
| Extern | 67 | 20 (8–42) | 3 (− 1–10) | ||
| Quality of smear | |||||
| Adequate | 226 | 66.5 (50–76) | < 0.0001* | 2 (0.5–7) | 0.0007* |
| Not adequate | 12 | 18 (8–40) | − 2 (− 12.8–0.4) | ||
| Quality of biopsy | |||||
| Very good/good | 206 | 18.0 (8–40) | 0.242 | ||
| Moderate/poor | 32 | 28.0 (10–48) | |||
| Plasma cell atypia | |||||
| Absent/low | 140 | 15 (8–30) | < 0.0001* | 1.8 (0.8–4) | 0.263 |
| Moderate/high | 91 | 33 (15–52) | 4 (− 4–11) | ||
| Bone marrow fibers | |||||
| Not increased | 188 | 17.5 (7.5–36) | < 0.0001* | 2 (0.5–7) | 0.002 |
| Increased | 40 | 51 (14.5–64) | 0.5 (− 4.5–3) | ||
| Amyloid | |||||
| Absent | 200 | 20 (8–45) | 0.880 | 1.8 (0–7) | 0.650 |
| Present | 29 | 17 (11–29) | 2 (1–4.7) | ||
| Clonality all | |||||
| Kappa | 124 | 26 (13–47) | < 0.0001* | 3 (0–9.7) | 0.027 |
| Lambda | 91 | 18 (9–44) | 1.8 (0–4) | ||
| Polyclonal | 23 | 3 (0–6) | 0.9 (0.8–1.6) | ||
| Clonality < 10% sBMPC | |||||
| Kappa | 73 | 19 (10–33) | < 0.0001* | 1 (0–3) | 0.656 |
| Lambda | 62 | 13 (9–28) | 1.7 (0–3) | ||
| Polyclonal | 22 | 3 (0–6) | 0.9 (0.8–1.6) | ||
| Surface immunophenotype | |||||
| CD19+ | 25 | 4 (0.5–8) | < 0.0001* | 1.0 (0.8–3) | 0.270 |
| CD19− | 212 | 22 (10–45) | 2 (0–7.5) | ||
| CD56+ | 134 | 26.5 (13–48) | < 0.0001* | 3 (0.2–10) | < 0.0001* |
| CD56− | 104 | 13 (5–28.5) | 1 (0.1–3) | ||
| CD117+ | 69 | 28 (13–47) | 0.010 | 3 (1–10) | 0.003 |
| CD117− | 168 | 17 (6.5–37.5) | 1.6 (0–4.9) | ||
| CD20+ | 21 | 18 (13–35) | 0.800 | 2 (0.2–6) | 0.654 |
| CD20− | 212 | 20 (8–42.5) | 1.8 (0.3–7) | ||
| Cytogenetic aberrations | |||||
| TP53 del./yes | 22 | 41 (17–52) | 0.036 | 1.5 (− 8–7) | 0.159 |
| TP53 del./no | 163 | 21 (10–40) | 2 (0.9–8) | ||
| 1p del./yes | 15 | 38 (18–43) | 0.156 | 6 (− 2–17) | 0.550 |
| 1p del./no | 168 | 21.5 (10–45) | 2.1 (0.7–7) | ||
| 1q gain/yes | 60 | 31.5 (15–56) | 0.005 | 2 (− 1.5–8.5) | 0.788 |
| 1q gain/no | 123 | 20 (10–36) | 3 (0.8–7) | ||
| IgH abnorm/yes | 109 | 25 (13–45) | 0.099 | 2.2 (0–6) | 0.704 |
| IgH abnorm/no | 76 | 18.5 (9–41) | 2 (0.3–8) | ||
| t(4;14)/yes | 16 | 27.5 (6.5–49) | 0.777 | 1.6 (− 4–6.5) | 0.534 |
| t(4;14)/no | 79 | 23 (15–47) | 2 (0–7) | ||
| t(11;14)/yes | 48 | 20.5 (14–37) | 0.101 | 2 (0–6) | 0.444 |
| t(11;14)/no | 46 | 31.5 (16–56) | 3 (0–11) | ||
| MYC abnorm/yes | 39 | 40 (20–60) | 0.0002* | 5 (− 3–10) | 0.337 |
| MYC abnorm/no | 144 | 19.5 (10–38) | 2 (0.5–6) | ||
| 13q del./yes | 82 | 29.5 (15–50) | 0.027 | 3 (− 2–8) | 0.835 |
| 13q del./no | 101 | 20 (9–38) | 2 (0.8–7) | ||
| Sum of cytogenetic aberrations | |||||
| 0 | 29 | 13 (8–23) | 0.0002* | 1.8 (0–3) | 0.229 |
| 1–3 | 114 | 20 (10–45) | 3 (1–8) | ||
| > 3 | 40 | 38.5 (23–56) | 3 (− 4–9.5) | ||
BMPC, bone marrow plasma cells; hBMPC, enumerated by histology review; sBMPC, enumerated by smear review; fBMPC, enumerated by flow cytometry; MUV, Medical University of Vienna (1, Division of Hematology and Hemostaseology; 2, Division of Oncology; 3, Division of Nephrology and Dialysis); del, deletion; abnorm, abnormality
*Statistically significant after Bonferroni correction for multiple comparisons