Extraskeletal Bone Formation following Suprapubic Prostatectomy: Case Report

Species Differences in Uroepithelium-Induced Bone Development: Observations on Transplants of Human Uroepithelium in Cortisone-Treated Mice

“…There are also a few reports on heterotopic bone for mation, diagnosed on an X-ray as myositis ossificans in the abdominal scars following suprapubic prostatectomy [15,16]. The authors interpreted this phenomenon as evi dence of osteoinductive potency of urinary bladder epi thelium accidentally transferred into muscles during sur gery.…”

“…Clinical reports pointing to the link between surgical injury of human uri nary bladder and the appearance of bone tissue in the adjacent muscles have suggested that human transitional epithelium possesses osteoinductive potency [15,16]. An attempt to show the osteoinductive property of human urinary bladder mucosa grafted into the anterior chamber of the guinea pig eye (a site considered immunoprotective) gave negative results and the lack of bone induction was explained by the histoimcompatibility reaction that destroys grafted epithelium [14], The application of im munosuppression by cortisone opened the possibility of prolonging xenogeneic epithelium survival long enough to reveal its osteoinductive properties [11], In mice corti sone does not inhibit heterotopic osteogenesis by epithe lial cells or by bone morphogenetic protein [5,7,8,11].…”

Is Heterotopic Bone Formation, Occurring Near a Cut Ureter, a Sign of Osteoinductive Potency of Human Urothelium?

“…dog or guinea pig), is capable of bone induction in adja cent muscles [2,4], There are reports of heterotopic bone formation occurring in humans; near ligated ureters [4], in the abdominal wall following suprapubic prostatecto my [5,6], and in the iliac muscles following autologous transplantation of urinary bladder mucosa [7], We are, however, very skeptical about the osteoinduc tive potential of the human urothelium. It appears that, in contrast with urothelium of dog, guinea pig, hamster, rab bit, and pig [8-14; for reviews, see 15,16], human urothe lium is devoid of osteoinductive potential [17,18].…”