Tamoxifen is a Selective Estrogen Receptor Modulator (SERM) with antifibrotic properties and has been used in the treatment of various fibrotic disorders like retroperitoenal fibrosis, fibrosing mediastinitis, fibrosing cerivicitis, and desmoid tumors (Cornelis and Oreopoulos, 2011). This evidence concerns the gene ESR1 and mediastinitis.