Table 1.
Patient and tumor characteristics: NSABP B-42 10-year update
| Characteristic | Placebo (n = 1983) | Letrozole (n = 1983) |
|---|---|---|
| No. (%) | No. (%) | |
| Age at random assignment, y | ||
| Younger than 60 | 675 (34.0) | 685 (34.5) |
| 60 and older | 1308 (66.0) | 1298 (65.5) |
| Race | ||
| Asian | 39 (2.0) | 39 (2.0) |
| Black or African American | 81 (4.1) | 70 (3.5) |
| Other or unknowna | 23 (1.2) | 26 (1.3) |
| White | 1840 (92.8) | 1848 (93.2) |
| Ethnicity | ||
| Hispanic or Latino | 39 (2.0) | 53 (2.7) |
| Not Hispanic or Latino | 1864 (94.0) | 1849 (93.2) |
| Unknown | 80 (4.0) | 81 (4.1) |
| Pathologic nodal status | ||
| Negative | 1134 (57.2) | 1145 (57.7) |
| Positive | 849 (42.8) | 838 (42.3) |
| Lowest BMD T-score | ||
| ≤ -2.0 | 493 (24.9) | 489 (24.7) |
| > -2.0 | 1490 (75.1) | 1494 (75.3) |
| Surgery type | ||
| Lumpectomy | 1208 (60.9) | 1201 (60.6) |
| Mastectomy | 775 (39.1) | 782 (39.4) |
| HER2 status | ||
| Positive | 278 (14.0) | 287 (14.5) |
| Negative | 1547 (78.0) | 1546 (78.0) |
| Not done or unknown | 158 (8.0) | 150 (7.6) |
| Duration of tamoxifen prior to randomization, mo | ||
| 0 | 1212 (61.1) | 1207 (60.9) |
| 1-12 | 164 (8.3) | 150 (7.6) |
| 13-24 | 254 (12.8) | 259 (13.1) |
| 25-36 | 353 (17.8) | 367 (18.5) |
| Duration of AI prior to randomization, mo | ||
| ≤36b | 412 (20.8) | 399 (20.1) |
| 37-48 | 192 (9.7) | 207 (10.4) |
| 49-60 | 992 (50.0) | 970 (48.9) |
| >60 | 387 (19.5) | 407 (20.5) |
a
Race and ethnicity categories were based on the report submitted by accruing sites upon enrollment. Other race categories include Native Hawaiian or Other Pacific Islander, American Indian or Alaska Native, and multiracial. AI = aromatase inhibitor; BMD = bone mineral density; NSABP = National Surgical Adjuvant Breast and Bowel Project.
b
Duration was unknown for 1 placebo patient in this category.