ORIGINAL ARTICLE: PDF OnlyGiant Multilocular Prostatic Cystadenoma A Distinctive Lesion of the Retroperitoneum in Men A Report of Two CasesMaluf, Horacio M. M.D.; King, Mary E. M.D.; DeLuca, Frank R. M.D.; Navarro, Jose M.D.; Talerman, Aleksander M.D.; Young, Robert H. M.D.Author Information From the Department of Pathology, Harvard Medical School and the James Homer Wright Pathology Laboratories of the Massachusetts General Hospital, Boston, Massachusetts (H.M.M., R.H.Y.), Department of Pathology, College of Medicine of the University of Illinois at Chicago, Illinois (M.E.K.), Department of Surgery, Albert Einstein College of Medicine, New York, New York (F.R.D.), Hospita Cordoba, Cordoba, Argentina (J.N.), and Department of Pathology and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania (A.T.). The American Journal of Surgical Pathology: February 1991 - Volume 15 - Issue 2 - p 131-135 Buy Abstract Two examples of large, multiloculated, cystic tumors that arose within the pelvis in men of 28 and 37 years of age are described. The tumors were composed of glands and cysts lined by prostatic-type epithelium lying in a hypocellular fibrous stroma. The prostatic nature of the lesions was confirmed by immunohistochemical staining of the epithelium for prostate-specific antigen and prostatic acid phosphatase. Two apparently similar lesions were found in the literature; one tumor was attached to the prostate by a pedicle, and the other arose in the retrovesical space. These tumors, for which we propose the designation “giant multilocular prostatic cystadenoma,” appear to be benign, although they may recur if incompletely excised. They may pose considerable diagnostic difficulty if the prostatic nature of the epithelium is not appreciated, an error that is likely if a relationship to the prostate is not recognized. This lesion should be included in the differential diagnosis of retroperitoneal cystic tumors in men. © Lippincott-Raven Publishers.