| Features | n | Frequencies |
| Normal | 220 | 59.2% |
| Nodular opacities | 68 | 18.3% |
| spiculated masses | 16 | 4.3% |
| Micro calcifications | 12 | 3.2% |
| Macrocalcifications | 12 | 3.2% |
| Lymph nodes | 12 | 3.2% |
| Others | 12 | 3.2% |
| No anwser* | 20 | 5.4% |
| Total obs. | 372 | 100% |