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Updated: Apr 4, 2026

Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection
Published on: October 12, 2017
[Melanosis of the urinary bladder]
J Wöllner1, J Janzen2, J Pannek3
1Neuro-Urologie, Schweizer Paraplegiker Zentrum, Guido A. Zäch Straße 1, CH-6207, Nottwil, Schweiz. jens.woellner@paraplegie.ch.
Abstract:
Melanosis of the bladder is rare. Only 10 cases have been described in the literature. We present the case of an 80-year-old woman with neurogenic lower urinary tract dysfunction due to spinal paralysis. During the diagnostic work-up which included cystoscopy, black spots in the bladder wall were observed. Histopathological evaluation revealed a benign suburothelial melanosis. Thus, with cystoscopic suspicion of a malignancy (melanoma), a biopsy is mandatory and regular cystoscopic follow-up is recommended.
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