Table 1 Characteristics of patients and healthy volunteers
| Â | Patients | Healthy volunteers | ||||||
|---|---|---|---|---|---|---|---|---|
| Â | Stage I | Stage II | Total | |||||
All | 237 | (67.3) | 115 | (32.7) | 352 | (100.0) | 35 | Â |
Age mean (SD) | 57 | (11) | 57 | (12) | 57 | (11) | 42.4 | (11) |
Race, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 White | 199 | (84.0) | 92 | (80.0) | 291 | (82.7) | 26 | (74.3) |
 Black | 17 | (7.2) | 13 | (11.3) | 30 | (8.5) | 3 | (8.6) |
 Hispanic | 7 | (3.0) | 2 | (1.7) | 9 | (2.6) | 1 | (2.9) |
 Asian, Hawaiian, Pacific Islander | 7 | (3.0) | 4 | (3.5) | 11 | (3.1) | 3 | (8.6) |
 Other/unknown | 7 | (3.0) | 4 | (3.5) | 11 | (3.1) | 2 | (5.7) |
Education, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 HS or less | 29 | (12.2) | 13 | (11.3) | 42 | (11.9) | 0 | (0.0) |
 Some college | 51 | (21.5) | 36 | (31.3) | 87 | (24.7) | 8 | (22.9) |
 College or more | 157 | (66.2) | 66 | (57.4) | 223 | (63.4) | 27 | (77.1) |
Hormone receptor status, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 Positive | 198 | (83.5) | 96 | (83.5) | 294 | (83.5) | na |  |
 Negative | 39 | (16.5) | 19 | (16.5) | 58 | (16.5) | na |  |
Local treatment, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 Lumpectomy | 172 | (72.6) | 80 | (69.6) | 252 | (71.6) | na |  |
 Mastectomy | 65 | (27.4) | 35 | (30.4) | 100 | (28.4) | na |  |
Systemic therapy, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 Chemotherapy only | 33 | (13.9) | 21 | (18.3) | 54 | (15.3) | na |  |
 Hormone therapy only | 124 | (52.3) | 22 | (19.1) | 146 | (41.5) | na |  |
 Both | 51 | (21.5) | 65 | (56.5) | 116 | (33.0) | na |  |
 No systemic therapy | 29 | (12.2) | 7 | (6.1) | 36 | (10.2) | na |  |
Months since diagnosis | Â | Â | Â | Â | Â | Â | Â | Â |
 Median (25th, 75th) | 29 | (23,38) | 31 | (22,38) | 30 | (23,38) | na |  |
Overall Health, n (%) | Â | Â | Â | Â | Â | Â | Â | Â |
 Excellent/very good | 159 | (67.1) | 70 | (60.9) | 229 | (65.1) | 32 | (91.4) |
 Other | 78 | (32.9) | 45 | (39.1) | 123 | (34.9) | 3 | (8.6) |