Table 2.

Comparison of clinicopathologic characteristics between B1mutER+, B1mutER, B2mutER+, and sporadic ER+ tumors

B1mutER+ (n = 16)B1mutER (n = 57)B2mutER+ (n = 36)SporER+ (n = 182)
n (%)n (%)Pan (%)Pan (%)Pa
BRCA1-likeBRCA1-like2 (12.5%)49 (86%) 22 (5.6%)4 (2.6%)
Sporadic-like14 (87.5%)8 (14%)<0.00134 (94.4%)0.39147 (97.4%)0.04
Not tested00031
BRCA2-likeBRCA2-like10 (62.5%)31 (60.8%)30 (83.3%)49 (32.5%)
Sporadic-like6 (37.5%)20 (39.2%)0.906 (16.7%)0.10102 (67.5%)0.02
Not tested06031
BRCA1 MethMethylated1 (2%)
Nonmethylated10 (100%)44 (100%)ND0 90%)ND49 (98%)0.65
Not done61336132
PR IHCNegative8 (57.1%)48 (100%)21 (60%)51 (30.9%)
Positive6 (42.9%)0 (0%)<0.00114 (40%)0.85114 (69.1%)0.05
Unknown29117
HER2 IHCNegative14 (93.3%)46 (100%)31 (93.9%)131 (80.4%)
Positive1 (6.7%)0 (0%)0.082 (6.1%)0.9432 (19.6%)0.22
Unknown111319
HistologyIDC10 (83.3%)24 (100%)35 (100%)139 (87.4%)
ILC2 (16.7%)0 (0%)0.040 (0%)0.0120 (12.6%)0.68
Unknown433123
GradeGrade 1/24 (50%)3 (13.6%)22 (62.9%)71 (65.7%)
Grade 34 (50%)19 (86.4%)0.0413 (37.1%)0.5037 (34.3%)0.37
Unknown835174
Age (median ± SD)45 ± 11.743 ± 9.40.0441 ± 11.70.0448 ± 8.60.65
  • NOTE: Patients with unknown characteristics were not included in P value calculations; therefore, percentages for these groups are not depicted in the table.

  • Abbreviations: B1mutER+, BRCA1-mutated ER+; B1mutER, BRCA1-mutated ER; B2mutER+, BRCA2-mutated ER+; IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; ND, not determined; SporER+, sporadic ER+.

  • aP value for comparison of BRCA1-mutated ER+ tumors with BRCA1-mutated ER tumors, BRCA2-mutated ER+ tumors, and sporadic ER+ tumors, respectively.