Table 1.
Patient and tumor characteristics at baselinea
| Characteristics | Metformin (n = 141) | Placebo (n = 171) |
|---|---|---|
| Age, mean (SD), y | 58.1 (6.9) | 57.5 (7.9) |
| Weight, mean (SD), kg | 72.6 (14.1) | 76.6 (17.5) |
| BMI, mean (SD), kg/m2 | 27.3 (5.2) | 28.9 (6.4) |
| Postmenopausal, No. (%) | 141 (100) | 171 (100) |
| Receptor status, No. (%) | ||
| ER/PR negative | 141 (100) | 171 (100) |
| HER2 status, No. (%) | ||
| HER2 positive | 32 (22.7) | 27 (15.8) |
| HER2 negative | 109 (77.3) | 144 (84.2) |
| Any (neo)adjuvant chemotherapy, No. (%) | ||
| Yes | 139 (98.6) | 168 (98.2) |
| No | 2 (1.4) | 3 (1.8) |
| T stage, No. (%) | ||
| T1 | 55 (39.0) | 73 (42.7) |
| T2 | 77 (54.6) | 80 (46.8) |
| T3 | 9 (6.4) | 18 (10.5) |
| N stage, No. (%) | ||
| N0 | 94 (66.7) | 105 (61.4) |
| N1 | 34 (24.1) | 40 (23.4) |
| N2 | 8 (5.7) | 18 (10.5) |
| N3 | 5 (3.5) | 8 (4.7) |
a
BMI = body mass index; ER = estrogen receptor; PR = progesterone receptor.