Urethra
General
Melanoma

Author: Turki Al-Hussain, M.D. (see Authors page)

Revised: 8 November 2017, last major update June 2012

Copyright: (c) 2002-2017, PathologyOutlines.com, Inc.

PubMed Search: Urethra melanoma "loattrfree full text"[sb]

Cite this page: Al-Hussain, T. Melanoma. PathologyOutlines.com website. http://pathologyoutlines.com/topic/urethramelanoma.html. Accessed November 19th, 2017.
Definition / general
  • Adults, mean age 73 years
  • Urethra is the most common site of origin of malignant melanoma in the urinary tract
  • Usually involves distal urethra in men and women
  • Less common in bladder
  • 5 year survival ~20% (may die of unrelated causes, Am J Surg Pathol 2000;24:785)
Treatment
  • Total urethrectomy plus bilateral inguinal node dissection
Gross description
  • Polypoid, mean 2.6 cm
Microscopic (histologic) description
  • Vertical growth phase often has prominent nodular component
  • Also radial growth phase
  • Abundant eosinophilic cytoplasm with large nuclei and prominent nucleoli
  • Numerous mitoses
  • Melanin pigment usually present but often focal
Differential diagnosis
  • Sarcomatoid carcinoma
  • Urothelial carcinoma