Stromal changes related to aggressive prostate cancer are decreased androgen [3] and transforming growth factor beta (TGF-beta) receptors [4–6], increased platelet derived growth factor receptor beta (PDGFR-beta) [7], increased hyaluronic acid [8], decreased density of mast cells [9] and increased density of macrophages and blood vessels [10, 11]. The gene discussed is PDGFRB; the disease is prostate cancer.