Figure 2.

Secretory carcinoma of the breast aka juvenile carcinoma: low-grade basal tumour. (A) Immunohistochemistry. Nuclear staining of TRK detected by pan-TRK IHC. (B) FISH. t(12:15) ETV6-NTRK3 fusion using an ETV6 break-apart probe. Due to the prevalence of ETV6-NTRK3 gene fusions, an ETV6 break-apart probe is typically used. FISH image provided by courtesy of Dr Hanina Hibshoosh, Columbia University. FISH, fluorescence in situ hybridisation; IHC, immunohistochemistry; TRK, tropomyosin receptor kinase.