Table 2

Available breast pathology and receptor status in 1116 index cases tested for BRCA1 and BRCA2 mutations

Sporadic BRCA1/2negativeFamilial BRCA1/2negativeBRCA1 indexBRCA1 negative phenocopies*BRCA2 index
Number11375612615106
Median age3246405643
Lobular7/113 (4%)80/756 (11%)2/126 (2%)3/15 (20%)3/106 (3%)
LCIS1/113 (1%)11/756 (1.5%)0/1260/150/106
DCIS9/113 (8%)65/756 (9%)5/126 (4%)1/15 (7%)6/106 (6%)
Mucinous1/113 (1%)2/7561/1261/15(7%)0/106
Grade 1 IDC5/95 (6%)111/598 (18%)3/117 (3%)1/10 (10%)3/97 (3%)
Grade 2 IDC20/95 (21%)249/598 (43%)19/117 (16%)5/10 (50%)42/97 (44%)
Grade 3 IDC70/95 (73%)238/598 (39%)96/117 (82%)4/10 (40%)52/97 (53%)
Her2 +ve7/40 (17%)52/169 (31%)0/51 (0%)1/5 (20%)2/22 (9%)
ER +ve30/66 (45%)373/463 (81%)22/87 (24%)8/11 (73%)65/80 (78%)
ER −ve36/66 (55%)90/463 (19%)65/87 (76%)3/11 (27%)15/80 (22%)
Grade 3 triple −ve20/66 (30%)34/463 (7%)51/87 (63%)1/11 (9%)9/80 (11%)
Grade 3 ER −ve, no Her2 status9/66 (13%)19/463 (4%)7/87 (9%)3/11 (25%)2/80 (3%)
Grade 3 ER −ve, Her2 +ve4/26 (15%)12/43 (28%)0/51 (0%)1/12 (8%)1/9 (11%)
Assumed† grade 3 triple −ve28/95 (30%)48/463 (10%)58/87 (67%)2/10 (20%)11/80 (14%)
  • *Women testing negative for the family BRCA1 mutation with breast cancer.

  • †This is assumed on the basis that untested grade 3 ER-negative tumours have the same ratio as those tested for Her2.

  • DCIS, ductal carcinoma in situ; ER, oestrogen receptor; IDC, invasive ductal carcinoma; LCIS, lobular carcinoma in situ.