Angiosarcoma of the Prostate
Article Outline
A 67-year-old man was diagnosed with adenocarcinoma of the prostate and received radiation therapy. He presented with urinary tract obstructive symptoms 7 years later and underwent transurethral resection of the prostate (TURP) followed by pelvic exenteration.
Grossly, the prostate was replaced by a 7.5 cm hemorrhagic mass that extended into the bladder (fig. 1). Histologically, there was a neoplastic spindle proliferation that formed irregular vascular channels which dissected through the stroma of the prostate and bladder. Other areas were more solid and admixed with the vascular spaces (fig. 2). The channels were lined by neoplastic endothelial cells displaying nuclear atypia. Endothelial cell differentiation in the tumor was confirmed by positive immunohistochemistry for endothelial markers CD31, CD34 and Factor VIII-related antigen. There was no evidence of residual adenocarcinoma of the prostate, as supported by negative pan-cytokeratin, prostate specific antigen and prostate specific acid phosphatase immunostains. These features are those of an angiosarcoma.
Figure 1.
Gross appearance of angiosarcoma of prostate, with extension into bladder.
Figure 2.
Angiosarcoma with solid growth and vascular spaces, some with red cells, formed by malignant endothelial cells.
Primary sarcomas of the prostate are rare, accounting for about 0.1% of all prostatic malignancies.1, 2 Angiosarcoma, a malignant endothelial tumor, is exceptionally rare, with only about 8 cases reported in the literature.2, 3 Angiosarcoma of the prostate has been diagnosed in patients at a median age of 35 years (range 2 to 60 years).2, 3 Patients typically present with hematuria and dysuria.
Radiation exposure has been linked to sarcomas of the prostate but considering the frequency of radiotherapy, these prostatic post-irradiation sarcomas are rare, with only a few documented cases.2 A post-irradiation sarcoma may be designated as such if it develops in the irradiated field, and there is histological establishment of the diagnosis of sarcoma, a latency of at least 3 years between irradiation and the appearance of the tumor, and documentation that the sarcoma occurred in tissue that was normal before radiotherapy. Most cases of post-irradiation prostatic sarcoma reported in the literature were diagnosed after radiation for prostatic carcinoma, and so should not formally be considered post-irradiation sarcoma. Therefore, the current case also does not qualify as a post-irradiation sarcoma since the sarcoma developed in prostatic tissue that was not normal, having been previously involved with prostatic adenocarcinoma.
Angiosarcoma of the prostate can metastasize to lymph nodes, lung, spleen and liver. Most men die of disease 1 to 6 months after diagnosis.
References
PII: S0022-5347(11)05584-4
doi:10.1016/j.juro.2011.11.007
© 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc All rights reserved.