Table 1.
Summary of the clinicopathological and molecular characteristics of the index cases.
| Characteristic | BRCA1/ER-BC | BRCA1/ER+BC |
|---|---|---|
| Age | 54 | 52 |
| Sex | Female | Female |
| Histological grade | 3 | 2 |
| Mitoses/ 10 HPF | 81 | 15 |
| ER | Negative | Positive |
| PR | Negative | Negative |
| HER2 | Negative | Negative |
| BRCA1 mutation | c.124delA/p.Ile42TyrfsX8 | c.4485-?_4986+?del/p.Ser1496CysfsX14 |
| Somatic BRCA1 wild-type allele * | Loss | Loss |
| TP53 mutation | c.927_928delTA | c.951C>T |
| Molecular subtype | Basal-like | Luminal B |
| Tumour cell content GAP* (H&E) + | 71% (70%) | 42% (60%) |
Mitoses 10/HPF (per 10 high power field). Molecular subtype determined by single sample predictors [29] according to Hu et al. [30] and Parker et al. [31].
*
Defined by Genome Alteration Print (GAP) based on single nucleotide polymorphism array data (SNP6, Affymetrix)[27].
+
Haemotoxylin and Eosin staining of frozen tumour samples.