Estimated probability of upstaging or change to worse prognostic group by unilateral bone marrow biopsy, according to risk group for bone marrow involvement (data obtained from the patients of the derivation group)
. | Low Risk (Zs < 0) . | . | . | Standard Risk (Zs 0-9) . | . | . | High Risk (Zs ≥ 10) . | . | . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Prognostic group* . | N . | BM+, n(%) . | Change, n(%) . | N . | BM+, n(%) . | Change, n(%) . | N . | BM+, n(%) . | Change, n(%) . | ||||||
| IPS | |||||||||||||||
| 2 or less | 317 | 0 (0) | 0 (0) | 171 | 4 (2.3) | 3 (1.8) | 52 | 9 (17.3) | 6 (11.5) | ||||||
| 3 or more | 11 | 1 (9) | NA | 60 | 2 (3.3) | NA | 98 | 28 (28.6) | NA | ||||||
| Stage | |||||||||||||||
| Early | 387 | 1 (0.3) | 1 (0.3) | 55 | 0 (0) | 0 (0) | 0 | 0 (0) | 0 (0) | ||||||
| Advanced | 16 | 0 (0) | NA | 210 | 7 (3.3) | 5 (2.4) | 158 | 38 (24.1) | 18 (11.4) | ||||||
. | Low Risk (Zs < 0) . | . | . | Standard Risk (Zs 0-9) . | . | . | High Risk (Zs ≥ 10) . | . | . | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Prognostic group* . | N . | BM+, n(%) . | Change, n(%) . | N . | BM+, n(%) . | Change, n(%) . | N . | BM+, n(%) . | Change, n(%) . | ||||||
| IPS | |||||||||||||||
| 2 or less | 317 | 0 (0) | 0 (0) | 171 | 4 (2.3) | 3 (1.8) | 52 | 9 (17.3) | 6 (11.5) | ||||||
| 3 or more | 11 | 1 (9) | NA | 60 | 2 (3.3) | NA | 98 | 28 (28.6) | NA | ||||||
| Stage | |||||||||||||||
| Early | 387 | 1 (0.3) | 1 (0.3) | 55 | 0 (0) | 0 (0) | 0 | 0 (0) | 0 (0) | ||||||
| Advanced | 16 | 0 (0) | NA | 210 | 7 (3.3) | 5 (2.4) | 158 | 38 (24.1) | 18 (11.4) | ||||||
Vertical sums are different in IPS and stage evaluations, because some patients had missing IPS values. The number and the percentage of patients who were upstaged (from stage I/II/III to IV) or upgraded with respect to IPS (from 2 to 3) are shown under the column “Change.” NA indicates not applicable; BM+, positive bone marrow biopsy.