Paraneoplastic syndromes in prostate cancer

Prostate cancer is the second most common urological malignancy to be associated with paraneoplastic syndromes after renal cell carcinoma. These syndromes tend to occur in the setting of late stage and aggressive tumors with poor overall outcomes. Recognition of these syndromes is clinically important as it might lead to the detection of underlying malignancy and impact on the treatment options available. The literature features around 100 cases of paraneoplastic syndromes associated with prostate cancer and these include endocrine manifestations, neurological entities, dermatological conditions, and other syndromes. Over 70% of cases document the syndrome as the initial clinical manifestation of prostate cancer, while in just under 20% the syndrome was an initial sign of disease progression to the castrate-resistant state. The vast majority of cases involved advanced metastatic malignancy. The syndromes generally resolve upon institution of treatment for the underlying prostate cancer, but some syndromes require specific therapies. Some syndromes are associated with serum markers that are readily detectable and demonstration of these putative markers within prostate cancer tissue at an individual level would firmly link the paraneoplastic syndrome with its underlying prostatic malignancy. The causes of paraneoplastic syndromes in prostate cancer are incompletely understood, and further research into their biology might shed more light on the complex molecular mechanisms that underpin prostate cancer and its lethal potential.