Table 3. Patient and tumor characteristics among patients with small tumors of low-to-intermediate grade.
| Variable | No-RT group (n = 41) No. (%) | RT group (n = 109) No. (%) | p-value |
|---|---|---|---|
| Age (yr) | 0.455 | ||
| ≤ 40 | 17 (41) | 38 (35) | |
| > 40 | 24 (59) | 71 (65) | |
| Tumor size (cm) | 0.002 | ||
| ≤1 | 31 (76) | 51 (47) | |
| >1 | 10 (24) | 58 (53) | |
| Nuclear grade | 0.003 | ||
| 1 | 27 (66) | 42 (39) | |
| 2 | 14 (34) | 67 (61) | |
| Margin width (mm) | < 0.001 | ||
| <2 | 7 (17) | 71 (65) | |
| ≥2 | 34 (83) | 38 (35) | |
| ER | 0.335 | ||
| Negative | 1 (2) | 4 (4) | |
| Positive | 39 (95) | 95 (87) | |
| Unknown | 1 (2) | 10 (9) | |
| PR | 0.115 | ||
| Negative | 1 (2) | 9 (8) | |
| Positive | 39 (95) | 89 (82) | |
| Unknown | 1 (2) | 11 (10) | |
| HER2 | 0.134 | ||
| Negative | 28 (68) | 61 (56) | |
| Equivocal | 4 (10) | 18 (17) | |
| Positive | 7 (17) | 12 (11) | |
| Unknown | 2 (5) | 18 (17) | |
| Tamoxifen | 0.028 | ||
| No | 9 (22) | 45 (41) | |
| Yes | 32 (78) | 64 (59) |
RT=radiation therapy; ER=estrogen receptor; PR=progesterone receptor; HER2=human epidermal growth factor receptor 2.