It has also been shown that SDC has AR pathways and ADT-resistance mechanisms similar to prostate carcinoma [10]. This is further confirmed by the fact that SDC (both de novo and CXPA) has overexpression of AR and HER2, approximately 78-96% and 29%-46%, respectively, with co-expression reported in 30% of the cases worldwide [4]. The gene discussed is ERBB2; the disease is prostate carcinoma.