Table 1.
Participant Characteristics at Baseline
| Low-dose tamoxifen (n=34) | Placebo (n=38) | |
|---|---|---|
| Age at study in years | ||
| Median (IQR) | 43.7 (34.3 to 48.8) | 44.1 (34.6 to 47.0) |
| Race/ ethnicity (n, %) | ||
| Non-Hispanic whites | 27 (79%) | 31 (82%) |
| Body Mass Indexin Kg/m2 | ||
| Median (IQR) | 25.0 (21.9 to 29.0) | 25.4 (22.1 to 30.8) |
| Primary Cancer diagnosis (n, %) | ||
| Hodgkin lymphoma | 29 (85%) | 33 (87%) |
| Non-Hodgkin lymphoma | 5 (15%) | 2 (5%) |
| Other | 0 (0%) | 3 (8%) |
| Time between cancer diagnosis and study in years | ||
| Median (IQR) | 16.6 (12.5 to 24.8) | 17.1 (10.7 to 26.1) |
| Age at diagnosis of primary cancer in years | ||
| Median (IQR) | 23.4 (17.5 to 29.0) | 19.9 (15.9 to 28.4) |
| Dose of radiation to chest for primary cancer in Gy | ||
| Median (IQR) | 30.3 (21.0 to 36.6) | 29.8 (21.0 to 38.0) |
| 1200-2599 cGy | 15 (44.1%) | 16 (42.1%) |
| ≥2600 cGy | 19 (55.9%) | 22 (57.9%) |
| Radiation field | ||
| Mantle | 21 (61.8%) | 26 (68.4%) |
| Mediastinal | 4 (11.8%) | 3 (7.9%) |
| Mini-mantle | 4 (11.8%) | 2 (5.3%) |
| Other | 5 (14.7%) | 7 (18.4%) |
| Pelvic radiation for primary cancer | ||
| Yes (n, %) | 4 (12%) | 4 (11%) |
| Alkylating agent exposure (n, %) | ||
| Yes | 6 (18%) | 5 (14%) |
| Postmenopausal at study (n, %) | ||
| Yes | 13 (38%) | 15 (40%) |
| Age at menarche in years | ||
| Median (IQR) | 12 (11 to 14) | 13 (12 to 14) |
| Age at first childbirth in years in years | ||
| Median (IQR) y | 28 (27 to 31) | 26 (21 to 31) |
| Family history of breast cancer in first-degree relatives (n, %) | ||
| Yes | 12 (35%) | 15 (40%) |
| Baseline estradiol in pg/mL | ||
| Pre-menopausal | 85 (0 to 389) | 87 (0-242) |
| Post-menopausal | 14.7 (1.3 to 226) | 9.8 (4.6-145) |
| Baseline Percent Mammographic Breast Dense area | ||
| Median (range) | 51.0% (25% to 85%) | 50.0% (25% to 95%) |
| Mean (±SD) | 52.6%±18.5% | 50.4±20.7% |
| Baseline Insulin-like growth factor-1 levels (ng/mL) | ||
| Median (range) | 166 (82 to 258) | 148 (78 to 289) |
| Mean (±SD) | 160.1 (41.0) | 156.8 (48.8) |
| Baseline Insulin-like growth factor binding protein levels (ng/mL) | ||
| Median (range) | 4730 (2430 to 6090) | 4260 (1990 to 8880) |
| Mean (±SD) | 4601.8 (782.0) | 4382.2 (1147.8) |