FLT4 and ductal breast carcinoma in situ: We recently showed that several proangiogenic factors, including fibroblast growth factor receptor (FGFR)-1, vascular endothelial growth factor (VEGF)-C, its receptor Flt-4, and the endothelin A receptor (ETAR), are highly expressed in DCIS, suggesting that in situ carcinomas can induce angiogenesis and lymphangiogenesis [29].