Table 2.
Characteristics of the gene expression datasets included in this study
| Dataset | GEO: GSE1456 | GEO: GSE3494 | GEO: GSE2990 |
|---|---|---|---|
| Patients, n | 159 | 249 | 101 |
| Time of sample collection | 1994–1996 | 1987–1989 | 1993–1995 |
| Institution | Karolinska Institutet, Stockholm, Sweden | Karolinksa Institutet, Uppsala, Sweden | John Radcliffe Hospital, Oxford, UK |
| Mean age, years | 58 | 62 | 58 |
| Mean tumor size, mm | 22 | 22 | 22 |
| Tumor size <21 mm, % | 62 | 51 | 58 |
| Grade 3, n (%) | 65 (41) | 196 (78) | 31 (31) |
| ER positive, n (%) | 130 (82) | 222 (89) | 85 (84) |
| Positive lymph nodes, n (%) | 60 (38) | 77 (31) | 15 (15) |
| Adjuvant HT, n (%) | 114 (72) | 67 (27) | 0 |
| Adjuvant chemotherapy, n (%) | 30 (19) | 60 (24) | 0 |
| Mean follow-up, years | 6.2 | 7.1 | 7.0 |
| Proportion relapsed, % | 25 | 36 | 40 |
| Platform | Affymetrix | Affymetrix | Affymetrix |
HT, hormone therapy.