Distinct mutational landscape of inverted urothelial papilloma

Mahmut Akgul, Gregory T. MacLennan, Liang Cheng

Research output: Contribution to journalComment/debate

3 Scopus citations


A recent study has identified gene mutations involving the MAPK/ERK pathway, particularly the HRAS gene, in all inverted urothelial papillomas (IUPs), in the absence of pathway mutations in TERT promoter, FGFR3, and TP53/RB1genes. Neither recurrence nor progression was observed in IUPs. These data support several longstanding hypotheses: (1) IUPs are benign and do not recur or progress; (2) they harbor mutations that are different from those of urothelial carcinoma; and (3) they arise through different molecular mechanisms than low- or high-grade urothelial carcinoma. As the most critical differential diagnosis in this context is inverted-type urothelial carcinoma, more comprehensive studies are needed to compare and contrast these entities.

Original languageEnglish (US)
JournalJournal of Pathology
StatePublished - Jan 1 2019



  • FGFR3
  • inverted urothelial papilloma
  • MAPK/ERK pathway
  • molecular genetics
  • TERT promoter mutation
  • urinary bladder

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

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