MMP7 and breast angiosarcoma: Matrix metalloproteinase-7 (MMP-7) is a newly identified biomarker of BA discovered from a large-scale proteomic study conducted by the Childhood Liver Disease Research Network.[4] Subsequent studies in patient cohorts in Asia, Europe, and North America have reproduced the superior discriminatory power of MMP-7 to differentiate BA from other forms of neonatal cholestasis.[5–9] However, these studies were exclusively conducted in term infants without any congenital anomalies, including congenital heart disease, which limits the broader application of MMP-7 screening.