Figure 1.

Somatic inactivating CTNNA1 mutations correlate with invasive lobular and ducto‐lobular mixed‐type breast cancer. (A–D) H&E processed samples harboring an inactivating CTNNA1 mutation and non‐mutated CDH1 alleles. Examples of a case diagnosed as ILC (A) and two cases that were initially diagnosed as IDC‐NOS, but that presented ducto‐lobular features (B, C) are shown. The case shown in D represents a typical IDC‐NOS and was diagnosed based on histological features and a positive E‐cadherin IHC analysis. Cancer study‐sample ID, CTNNA1 amino acid change (somatic mutation), and mRNA levels are indicated in the given order. The inset depicts initial (i) and revised (r) diagnosis. Samples can be cross‐referenced with Table 1; data were obtained from http://cancergenome.nih.gov. Scale bar = 100 μm.