Table 1.
Distribution and frequency of the microscopic spectrum of benign breast lesions in the study cohort of 4,341 women
| Benign Breast Disease Risk Level Category | Lesions | Number (%) |
|---|---|---|
| Risk 1: Nonproliferative | 7680 (63.0) | |
| Simple apocrine metaplasia | 2251 (18.5) | |
| Cysts | 2231 (18.3) | |
| Periductal mastitis/duct ectasia | 437 (3.59) | |
| Mastitis | 174 (1.43) | |
| Fibrosis | 1568 (12.9) | |
| Squamous metaplasia | 15 (0.12) | |
| Fibroadenoma | 1001 (8.21) | |
| Other nonproliferative lesions | 3 (0.02) | |
| Risk 2: Proliferative without atypia | 4233 (34.7) | |
| Simple adenosis | 724 (5.94) | |
| Sclerosing adenosis | 721 (5.92) | |
| Apocrine adenosis | 29 (0.24) | |
| Hyperplasia without atypia (usual type) | 1528 (12.5) | |
| Hyperplasia without atypia (apocrine type) | 125 (1.03) | |
| Papilloma | 354 (2.90) | |
| Radial scar | 193 (1.58) | |
| Associated Fibroadenoma | 559 (4.59) | |
| hyperplasia associated | 310 | |
| adenosis associated | 173 | |
| hyperplasia & adenosis associated | 76 | |
| Risk 3: Proliferative with atypia | 273 (2.4) | |
| Atypical ductal hyperplasia (ADH) | 135 (1.11) | |
| fibroadenoma associated | 9 | |
| simple adenosis associated | 6 | |
| sclerosing adenosis associated | 3 | |
| papilloma associated | 14 | |
| other lesion associated | 2 | |
| Atypical lobular hyperplasia (ALH) | 64 | |
| simple adenosis associated | 11 | |
| sclerosing adenosis associated | 2 | |
| radial scar associated | 3 | |
| Combination of ADH and ALH (ADH & ALH) | 22 (0.18) | |
| simple adenosis associated | 2 |
Total lesion number = 12,186