[Inverted papilloma of the bladder]

Area of Science:

• Urology
• Pathology

Background:

• Inverted papilloma (IP) of the urinary bladder is an uncommon bladder tumor.
• Fewer than 40 cases have been documented in medical literature.

Observation:

• Presents two cases of urinary bladder inverted papilloma.
• Observed transitional cellular structures with submerged pseudoinvasive growth.
• Noted a distinctive inversion of the villous structure.

Findings:

• The tumor exhibits benign clinical and histological characteristics.
• Long-term follow-up confirmed the benign nature of the observed cases.
• IP is classified as a benign tumor, distinct from common bladder papillomas due to growth direction and villous arrangement.

Implications:

• Adds to the limited case reports of urinary bladder inverted papilloma.
• Reinforces the benign classification of IP based on histological and clinical evidence.
• Suggests further research into the histogenesis of inverted papilloma is warranted.