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Keratinizing Squamous Metaplasia of the Bladder: A Review

Ahmad I.a · Barnetson R.J.b · Krishna N.S.c

Author affiliations

aBeatson Institute for Cancer Research and Departments of bPathology and cUrology, Southern General Hospital, Glasgow, UK

Corresponding Author

Imran Ahmad

Beatson Institute for Cancer Research

Garscube Estate, Switchback Road

Bearsden, Glasgow G61 1BD (UK)

Tel. +44 141 330 3973, Fax +44 141 201 2987, E-Mail imranahmad@doctors.net.uk

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Urol Int 2008;81:247–251

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Aims: Keratinizing squamous metaplasia is infrequently found in bladder biopsies and its clinical significance remains unclear, with studies linking it to the development of invasive squamous cell carcinoma. Once diagnosed, there is a dilemma how to treat and follow-up this group. Methods: We reviewed the literature on the topic with particular emphasis on natural history, management and subsequent follow-up. Results: Keratinizing squamous metaplasia of the bladder is rare. Pathognomonic findings on biopsy are required to confirm the diagnosis. Both synchronous diagnosis of urothelial tumour and subsequent tumour development on follow-up has been identified. Risk of malignant transformation increases in the presence of dysplasia as well as with extensive keratinization. Lesions should be treated with local transurethral resection. Considering the lack of evidence cystectomy cannot be justified for those with extensive lesions. Conclusion: Currently there is not enough data to identify keratinizing squamous metaplasia of the bladder as a pre-malignant condition; this term being reserved for those with obvious histological dysplasia. However at present all patients should undergo regular follow-up.

© 2008 S. Karger AG, Basel


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Article / Publication Details

First-Page Preview
Abstract of Review

Published online: October 16, 2008
Issue release date: October 2008

Number of Print Pages: 5
Number of Figures: 2
Number of Tables: 1

ISSN: 0042-1138 (Print)
eISSN: 1423-0399 (Online)

For additional information: https://www.karger.com/UIN

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