On the other hand, PSA rise during treatment with 223Ra has been reported and attributed to various reasons: (a) progression of metastatic soft tissue injuries no involved in the treatment, (b) bone tumor lysis, (c) bone progression, (d) non androgen dependent mechanism of action of 223Ra or (e) flare21,22,30–36. The gene discussed is KLK3; the disease is bone neoplasm.