[Report of 2 new cases of bladder inverted papilloma, one with them complicated with acute urinary obstruction].

Inverted papilloma is a rare tumour (2.2% of urothelial tumours) considered to be benign. The bladder is the most frequent site and growth tends to be endophytic towards the submucosa. Haematuria and obstruction symptoms appear to be the most typical clinical manifestations. Contribution of two cases of inverted bladder papilloma; one showing very unusual clinical development with relapsing acute urinary obstruction. Strict follow-up is recommended in spite of its benign behaviour as it may become associated to transitional cell carcinoma. Literature review on this tumoral entity in terms of etiology, clinical manifestations, diagnosis and treatment.