Malignant Ascites Associated with Carcinoma of the Prostate

BACKGROUND: Prostate cancer is the most common malignancy in men in the United States. Both at diagnosis and throughout the disease progression, it can metastasize to multiple organs, most commonly bone and lymph nodes. Effusions (either pleural or abdominal) are relatively uncommon. PATIENTS AND METHODS: We reviewed the medical literature including the case reports and post-mortem studies relating ascites to prostate cancer, identified through a MEDLINE search (human; all languages; 1969-2004). RESULTS: We found 12 published cases. Forty two percent of patients presented initially with ascites, in 50% ascites developed later with progressive disease, and 8% had ascites being the only site of recurrence. The response rate to endocrine therapy, including orchiectomy, was 25%. Ascites in these patients conferred a poorer prognosis. CONCLUSION: The development of ascites secondary to prostate cancer, either as an initial manifestation or recurrent disease, is not well known and may be unfamiliar to many physicians. If patients with history of prostate cancer develop malignant effusions, prostate specific antigen (PSA) immunohistostaining of the fluid can serve as a valuable adjunctive study for the diagnosis. This clinical situation becomes particularly important in patients with ascites with a carcinoma of unknown primary. Palliation can be achieved in patients with ascites secondary to prostate cancer using hormone manipulation. Lack of knowledge about this complication of prostate cancer may delay the diagnosis and treatment of this hormonally responsive malignancy.