Table 1.
Baseline characteristics of the entire study population and subgroups of patients who received adjuvant trastuzumab and those who did not receive adjuvant trastuzumab.
| Variables | All patients N = 91 (%) |
Treatment group N = 39 (%) |
Control N = 52 (%) |
p value |
|---|---|---|---|---|
| Age (years) | 61 (range 30–89) | 57 (30–76) | 65 (30–89) | 0.02 |
| Comorbid illness | 44 (48) | 18 (46) | 26 (50) | 0.83 |
| History of a secondary cancer | 16 (18) | 6 (15) | 10 (19) | 0.78 |
| ECOG performance status | ||||
| 0 | 77 (85) | 31 (80) | 46 (89) | 0.25 |
| 1 | 14 (15) | 9 (20) | 6 (11) | |
| Smoking history | 41 (45) | 20 (50) | 21 (40) | 0.39 |
| Current smoker | 8 (9) | 5 (13) | 3 (6) | 0.28 |
| Surgery | ||||
| Lumpectomy | 43 (47) | 17 (44) | 26 (50) | 0.67 |
| Mastectomy | 37 (41) | 14 (36) | 23 (44) | 0.51 |
| Bilateral mastectomy | 11 (21) | 8 (21) | 3 (6) | 0.04 |
| Node exam | ||||
| Sentinel node | 77 (85) | 34 (87) | 43 (83) | 0.77 |
| Complete nodal dissection | 13 (14) | 5 (13) | 8 (15) | 0.77 |
| Size in mm (mean ±) | 6.4 ± 2.7 | 7.8 ± 2.0 | 5.3 ± 2.6 | < 0.0001 |
| T status | ||||
| Tmic | 1 (1) | 0 | 1 (2) | |
| T1a | 33 (36) | 3 (8) | 30 (58) | < 0.0001 |
| T1b | 57 (63) | 36 (92) | 21 (40) | < 0.0001 |
| Gradea | ||||
| I | 14 (15) | 6 (15) | 8 (15) | 1.0 |
| II | 42 (46) | 14 (36) | 28 (54) | 0.13 |
| III | 34 (37) | 18 (46) | 16 (31) | 0.18 |
| Margin within 1 mm | 8 (9) | 3 (8) | 5 (10) | 1.0 |
| Hormone receptor status | ||||
| ER positive | 60 (66) | 27 (69) | 33 (64) | 0.65 |
| PR positive | 45 (50) | 20 (51) | 25 (48) | 0.83 |
| Adjuvant systemic therapy | 65 (71) | 39 (100) | 26 (50) | < 0.0001 |
| Adjuvant chemotherapy | 40 (44) | 39 (100) | 1 (2) | < 0.0001 |
| Adjuvant endocrine therapy | 53 (58) | 27 (69) | 26 (50) | 0.08 |
| Adjuvant radiation therapy | 52 (57) | 26 (67) | 26 (50) | 0.13 |
aGrade was unknown in one patient in the treatment group. ECOG Eastern Cooperative Oncology Group.