GIANT MULTILOCULAR PROSTATIC CYSTADENOMA

Abstract

A 57-year-old man presented with a 1-year history of a lower abdominal mass and dysuria. Excretory urography showed an anteriorly displaced bladder compressed by a large pelvic mass on lateral view. However, examination of the upper urinary tract was normal. Computerized tomography of the abdomen and pelvis revealed a large multiseptated pelvic mass with thickened irregular walls displacing the bladder and rectum. Different attenuations were in each loculus, and there was contrast material enhancement of the internal septa. Magnetic resonance imaging (MRI) of the pelvis demonstrated a large multiseptated pelvic mass with different signal intensities in each loculus, suggesting hemorrhagic or proteinaceous fluid components. Sagittal T1weighted image showed effects of the mass on the bladder and rectum (fig. 1). Exploration of the retroperitoneum revealed a large cystic mass apparently arising in the pelvic floor between the rectum and bladder. The mass was compressing and displacing the bladder anterolaterally and adhering to the bladder wall. The specimen was an approximately 15 3 10 3 8 cm. tan cystic mass weighing 300 gm. with a rough, shaggy surface. Cut section revealed multilocular cysts filled with brown, rusty appearing fluid. In several cysts there was transparent serous fluid. Size varied from minute to several cm. Microscopically, the cysts were lined by double layers of epithelium, reminiscent of prostate tissue (fig. 2). The larger cysts had flattened epithelium. The lining was focally multilayered or squamous metaplasia. The luminal borders of the glands stained positive with periodic acid-Schiff and alcian blue at pH 2.5. The epithelial cells were immunoreactive for prostate specific antigen. The stroma surrounding the glands was hypocellular and focally markedly hyalinized. No atypical feature was noted in the glandular or stromal component of the mass. The pathological findings were consistent with multilocular prostatic cystadenoma.