Table 3.
Clinicopathologic characteristics of breast cancers arising in patients with CHEK2 pathogenic/likely pathogenic germline alterations
| Median age, years (range) | 45 (25–75) |
| Clinical presentation | |
| Palpable mass | 19/35 (54%) |
| Mammographically-detected mass | 10/35 (29%) |
| Mammographically-detected calcifications | 6/35 (17%) |
| Mean non-treated tumor size, cm (range) | 1.3 (< 0.1 to 5.4) |
| Bilaterality | 4/35 (11%) |
| Multifocality | 7/35 (20%) |
| Lymph node metastasis | 13/34 (38%) |
| Invasive tumor typea,b | |
| Invasive ductal carcinomac | 38/44 (86%) |
| Invasive lobular carcinoma | 3/44 (7%) |
| Invasive carcinoma with ductal and lobular features | 2/44 (5%) |
| Papillary carcinoma | 1/44 (2%) |
| Hormone receptor profile | |
| ER + | 41/43 (95%) |
| ER + HER2−d | 34/43 (79%) |
| ER + HER2 + | 7/43 (16%) |
| ER− | 2/43 (5%) |
| ER-HER2− | 0/43 (0%) |
| ER-HER2 + | 2/43 (5%) |
| Ki67e | |
| ≤ 5% | 3/31 (10%) |
| 6–29% | 18/31 (58%) |
| ≥ 30% | 10/31 (32%) |
| Molecular subtype | |
| Luminal A | 9/36 (25%) |
| Luminal B | 25/36 (69%) |
| HER2-positive (non-luminal) | 2/36 (6%) |
| Basal-like | 0/36 (0%) |
| Nottingham grade‡ | |
| 1 | 8/44 (18%) |
| 2 | 25/44 (57%) |
| 3 | 11/44 (25%) |
| OncotypeDX | |
| < 17 (Low) | 5/12 (42%) |
| 18–30 (Intermediate) | 5/12 (42%) |
| > 31 (High) | 2/12 (16%) |
| MammaPrint | |
| Low-risk | 6/13 (46%) |
| High-risk | 7/13 (54%) |
aThree patients had multiple synchronous ipsilateral tumors
bFour patients had multiple synchronous bilateral tumors
cOne patient had invasive ductal carcinoma with minor apocrine component
dOne patient had an ER + HER2 + metachronous metastasis
ePre-treatment Ki67 for treated tumors
‡Pre-treatment histologic grade