HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS REGISTER		Author Keyword(s) Vol Page [Advanced]

This Article Full Text Full Text (PDF) All Versions of this Article: jcp.2007.049684v1 61/3/272    most recent Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this link to a friend Similar articles in this journal Similar articles in PubMed Add article to my folders Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Schwarz, S Articles by Brockhoff, G Search for Related Content PubMed PubMed Citation Articles by Schwarz, S Articles by Brockhoff, G Pubmed/NCBI databases Medline Plus Health Information Bladder Cancer

Value of multicolour fluorescence in situ hybridisation (UroVysion) in the differential diagnosis of flat urothelial lesions

¹ Department of Pathology, University of Regensburg, Regensburg, Germany
² Department of Urology, Hospital Eichstaett, Eichstaett, Germany
³ Department of Pathology, University of Aachen, Aachen, Germany
⁴ Department of Pathology, University of Vermont College of Medicine, Burlington, Vermont, USA

Correspondence to:
Gero Brockhoff, PhD, Department of Pathology, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg, Germany; gero.brockhoff{at}klinik.uni-regensburg.de

Aims: During the past 10 years, multitarget fluorescence in situ hybridisation has been established as a valuable adjunct in the cytological diagnosis of precancerous and malignant lesions of the urinary tract. The aim of the present study was to define its value in detecting chromosomal imbalances in patients with various flat urothelial lesions in routine paraffin-embedded bladder biopsy samples. In addition, the HER2 gene amplification and HER2 expression pattern were examined, since alterations of the HER2 expression patterns have been demonstrated in invasive bladder cancer.

Methods: 29 samples of normal urothelium and 86 flat urothelial lesions (hyperplasia, reactive atypia, dysplasia and carcinoma in situ (CIS)) from 73 patients were analysed patients using tissue microarrays and centromeric probes for chromosomes 3, 7 and 17, and gene-specific probes for 9p21/P16 and HER2 (UroVysion, PathVysion). The expression of HER2 was studied by immunohistochemistry.

Results: Polysomy of at least one of the chromosomes was found in about half of the dysplastic cells, and in more than 90% of cells in CIS or cells in invasive bladder tumours. Polysomic cells were found in only 17% of urothelial hyperplasia, reactive atypia and normal urothelium of healthy patients, whereas about 30% of non-neoplastic lesions in patients with concomitant urothelial carcinoma showed polysomy of at least one chromosome. These alterations indicate a field effect and are associated with synchronous development of dysplastic lesions of a higher grade. Deletion of the P16 locus was most frequently observed in aneuploid lesions, whereas overexpression of HER2 was found in 10–20% of invasive urothelial carcinomas, and only occasionally in CIS (5%). An altered HER2 expression pattern was present in non-neoplastic lesions (25%).

Conclusions: UroVysion fluorescence in situ hybridisation is a valuable tool for the detection of genetically unstable flat urothelial lesions, and can help to resolve difficult cases, particularly the differential diagnosis of reactive atypia and dysplasia.