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Rare melanosis in the urinary bladder and prostate: a case report
Pierre T C Tran1,2, Connor J Thellman2, Kirsten Woolf3
1College of Osteopathic Medicine of the Pacific, Western University of Health Sciences, 309 E 2nd Street, Pomona, CA 91766, United States.
Journal of Surgical Case Reports
|May 6, 2024
Summary
Melanosis, or abnormal melanin pigment deposition without melanocytes, is rare in the genitourinary tract. This case highlights the need to consider melanosis in the differential diagnosis of pigmented lesions during cystoscopy.
Area of Science:
- Urology
- Pathology
Background:
- Melanosis is characterized by aberrant melanin pigment deposition.
- It is exceptionally rare within the genitourinary tract, particularly the bladder and prostate.
Observation:
- A 74-year-old male presented with symptomatic benign prostatic hyperplasia.
- Cystourethroscopy revealed numerous flat, velvety, brown-black lesions on the bladder mucosa.
- Histological examination confirmed melanin pigment within the bladder mucosa and prostatic stroma.
Findings:
- Bladder biopsy showed urothelium with granular, black pigmentation and positive Fontana Masson stain for melanin.
- Transurethral resection of the prostate revealed nodular hyperplasia with focal stromal pigmentation.
- The findings indicate melanosis of the bladder and prostate.
Implications:
- The rarity of genitourinary melanosis necessitates further research into its clinical significance and benign nature.
- Melanosis should be included in the differential diagnosis for pigmented lesions observed during cystoscopy.
