Grade of DCIS and ER status: Sloane Project data based on 1684 cases
| Grade | High (%) | Intermediate (%) | Low (%) | Unknown (%) | Total (%) |
| 994 (59) | 490 (29) | 181 (11) | 19 (1) | 1684 | |
| ER positive | 325 (69) | 197 (94) | 79 (99) | 5 | 606 (79) |
| ER negative | 148 (31) | 12 (6) | 1 (1) | 161 (21) | |
| Unknown | 521 | 281 | 101 | 14 |
DCIS, ductal carcinoma in situ; ER, oestrogen receptor.