title: [The presence of muscularis mucosae in the urinary bladder of samples from transurethral resection].
abstract: OBJECTIVE
  The role of the muscularis mucosae (MM) of the bladder as a distinct histologic structure has been recently recognized. The prognostic implications of its distinction in patients with T1 bladder cancer is a matter of discussion with possible future implications in the classification of bladder cancer. However, the prevalence of this structure in transurethral resection (TUR) biopsies is unknown.
  
  
  METHODS
  A retrospective review of 60 bladder biopsies performed by TUR, all deep enough to include smooth muscle, is presented. In 48 cases (80%) superficial urothelial carcinoma (Tis, Ta, Tl) was present, in 9 (15%) biopsy evidenced inflammatory changes, and in 3 (5%) there was no remarkable histologic finding.
  
  
  RESULTS
  In 25 cases (42%) MM was identified either total or partially and in 14 cases (23%), although absent, its level was suggested by the presence of large vessels in the subepithelial connective tissue.
  
  
  CONCLUSIONS
  The MM of human urinary bladder can be identified in a high proportion of cases after TUR. The prognostic implications of such distinction are discussed.
authors.affiliation: Servicio de Urología, Hospital Príncipe de Asturias, Universidad de Alcalá de Henares, Madrid, España.
authors.forename: M
authors.initials: M
authors.lastname: Sánchez-Chapado
authors.forename: J
authors.initials: J
authors.lastname: Angulo Cuesta
mesh_terms: D000328:Adult; D000368:Aged; D002295:Carcinoma, Transitional Cell / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000473:pathology; D009130:Muscle, Smooth / Q000473:pathology*; D012189:Retrospective Studies; D001743:Urinary Bladder / Q000473:pathology*; D001749:Urinary Bladder Neoplasms / Q000473:pathology*
vernacular_title: La presencia de la muscularis mucosae de la vejiga urinaria en especímenes procedentes de resección transuretral.