Bilateral primary angiosarcoma of breast is an extremely rare disease. Only 4 cases had been described in the literature. Hypoxia inducible factor- 1 α (HIF-1α) is a transcription factor that binds to hypoxia response elements in the promoters of target genes. Vascular endothelial growth factor (VEGF) is an important signaling protein involved in angiogenesis. Wilms tumor -1 protein (WT-1) is a transcription factor that plays an important role in angiogenesis. We present a 29-year old female with bilateral primary angiosarcoma of breast. Five-μm sections were stained with CD31, FLI-1, HIF-1α, WT-1, VEGF, VEGF-R, D2-40, estrogen receptor, and progesterone receptor. The neoplastic cells show diffuse immunoreactivity to CD31, FLI-1, HIF- 1α, VEGF, VEGFR, and WT-1 protein. The neoplastic cells show no immunoreactivity to estrogen receptor, progesterone receptor and D2-40. In conclusion, HIF- 1α, WT-1 and VEGF are possible protagonists in the development of bilateral primary angiosarcoma of breast. The neoplastic process involves endothelial cell of blood vessels lineage rather than lymphatic lineage. Painless breast tumors in young women that are highly vascular at the time of biopsy should be considered as malignant until proven otherwise. Tissue biopsy is the gold standard in the diagnosis of primary angiosarcoma of breast.
Keywords: Breast; HIF-1α; VEGF; WT-1; angiosarcoma.