Abstract
Prostate cancer frequently metastasizes to bone, but bone marrow involvement is relatively less common. In advanced prostate cancer, significant bone marrow infiltration can result in hematologic abnormalities such as anemia and thrombocytopenia. We report the case of a patient who presented with a new diagnosis of thrombocytopenia at the same time that he presented with prostate cancer metastatic to bone. He was found to have immune thrombocytopenia (ITP) which responded to treatment with steroids. We discuss this case and review the literature on ITP in the setting of advanced malignancy.