Mucosal Changes in the Exstrophic Bladder: Is Delayed Timing of Reconstruction Associated with Premalignant Changes?

Abstract

Purpose Early closure of bladder exstrophy (BE) within the first hours of life is often recommended to prevent further environmental injury of the bladder mucosa. However, the impact of early closure in respect of the incidence of malignant changes and inflammation remains unclear. Therefore we examined polyps excised during primary closure in delayed reconstruction. Material and Methods From January 2006 to September 2008, in 13 patients with classical BE a primary closure (10 single-stage repairs and 3 staged repairs) was performed at a median age of 8.5 weeks (7 th – 10 th week). Mucosal specimens and polyps were obtained during surgery. Tissue sections were assessed by two investigators (S.B.; F.H.) independently. Histological analysis included histomorphological examination regarding inflammation, fibrosis, edema, squamous metaplasia, presence of vonBrunn nests, cystitis cystica and cystitis glandularis of the intestinal type (CGIT). Immunohistochemical analysis included CDx-2 and CK 20. Results Squamous metaplasia was detected in 76.9%. 92.3% showed at least minimal active inflammation. Cystitis cystica was diagnosed in 84.6%, vonBrunn nests in 23.1%. Only one case showed intestinal metaplasia within changes of CGIT. Dysplastic urothelium was not found. Immunohistochemically nuclear staining for CDx-2 was found within only one case with CGIT. No abnormal CK20 staining was found but CK20-positivity within superficial cells of the urothelium was detected in 92.3%. Conclusions - Delayed primary bladder closure does not induce histologically or immunohistochemically detectable premalignant changes. - In comparison to early bladder closure cystitis cystica and inflammation seems to be not more frequent in delayed closure around the 8 th week.