Table 2.

Distribution of grade and morphology of ER-positive and ER-negative tumors in BRCA1 and BRCA2 mutation carriers

BRCA1 Mutation CarriersBRCA2 Mutation Carriers
TypeER-Negative, n (%)aER-Positive n (%)ORb (95% CI)ER-Negative n (%)ER-Positive n (%)OR (95% CI)
Grade
 Grade 118 (1.2)28 (6.9)1.0012 (4.3)68 (7.4)1.00
 Grade 2191 (13.1)170 (41.6)0.57 (0.31–1.05)67 (24)442 (48.2)1.2 (0.60–2.4)
 Grade 31,246 (85.7)210 (51.5)0.12 (0.07–0.21)200 (71.7)408 (44.4)0.33 (0.17–0.6)
Morphology
 Ductal1,353 (58.8)385 (86.5)266 (85.8)889 (84)
 Lobular16 (2.7)21 (4.7)15 (4.8)110 (10.4)
 Medullaryc141 (23.5)17 (3.8)14 (4.6)13 (1.2)
 Other91 (15)22 (5)15 (4.8)46 (4.3)
  • aNumber of tumors (n) of each grade or morphology type by ER-status as a percentage (%) of all ER-negative or ER-positive tumors where this information is available.

  • bOR and 95% CI are for ER-positive versus ER-negative disease in grade 2 or grade 3 tumors compared with grade 1 tumors. These analyses were adjusted for age at diagnosis of breast cancer and country of origin.

  • cIncludes medullary and atypical medullary tumors.