Cystosarcoma of the seminal vesicle is a very rare malignant tumor; in the literature only four cases are reported. We present a case of cystosarcoma phyllodes arising in the right seminal vesicle of a 49-year-old man without any urinary symptom but with persistent constipation. Ultrasound examination showed a mass at the right superior base of the prostate subsequently studied with CT and MRI. The patient underwent vesiculectomy; his postoperative course was uneventful. The patient is still well, without evidence of recurrent disease. 1. Introduction The seminal vesicle is involved more frequently by tumors originating elsewhere, particularly prostatic carcinoma. Primary malignant seminal vesicle neoplasms are extremely uncommon: in addition to carcinomas and even more rare pure sarcomas, there is a distinctive group of mixed epithelial-stromal tumors that includes the cystosarcoma phyllodes reported in this case, exhaustively studied with ultrasound, computed tomography, and magnetic resonance. 2. Case Report A 49-year-old man was admitted with two months persistent constipation, incoercible with medical therapy. He did not report any urinary symptom, only a mild erectile dysfunction. On digital rectal examination his prostate was regular in size and consistency but with an extrinsic compression on the right-posterior wall by a mass. Transabdominal ultrasonography showed a localized cystic mass of about 7,3 × 5？cm, probably of the right seminal vesicle, characterized by multiple endoluminal septa. Transrectal US confirmed the origin of the lesion from the right seminal vesicle without infiltration of rectum, bladder, or prostate (Figure 1). Figure 1: Transrectal ultrasound. Multiloculated solid mass of the right seminal vesicle. Routine blood exams, including PSA and prostatic acid phosphatase, were normal. Magnetic resonance (MR) was performed and reported a 56 × 63 × 59？mm lesion of the right seminal vesicle with a fluid content and endoluminal central solid tissue caracterized by a sepimentated structure with enhancement after Gadolinium-DTPA. On T1 weighted images, some hyperintensities in small cavities, caused probably by past hemorrhages, were observed. Prostate and bladder were normal, without signs of infiltration. No local adenopathies were found (Figure 2). Figure 2: MRI of the pelvis. Axial (a) and sagittal (b) T2 sequence. Large mixed solid-fluid mass of the right seminal vesicle (arrows) without infiltration of adjacent structures. Colonoscopy confirmed a delayed fecal transit through the rectum and cystoscopy showed compression on the
R. H. Young, J. R. Srigley, M. B. Amin, T. M. Ulbright, and A. L. Cubilla, Tumors of the Prostate Gland, Seminal Vesicle, Male Urethra, and Penis, vol. 28 of Atlas Od Tumor Pathology, Armed Forces Institute of Pathology, Washington, DC, USA, 3rd edition, 2000, Edited by: J. Rosai.
P. Laurila, I. Leivo, H. Makisalo, M. Ruutu, and M. Miettinen, “Müllerian adenosarcomalike tumor of the seminal vesicle: a case report with immunohistochemical and ultrastructural observations,” Archives of Pathology and Laboratory Medicine, vol. 116, no. 10, pp. 1072–1076, 1992.
L. W. Xu, H. Y. Wu, Y. L. Yu, Z. G. Zhang, and G. H. Li, “Large phyllodes tumour of the seminal vesicle: case report and literature review,” Journal of International Medical Research, vol. 38, no. 5, pp. 1861–1867, 2010.