title: Is chromosome 9 loss a marker of disease recurrence in transitional cell carcinoma of the urinary bladder?
abstract: Investigation of transitional cell carcinoma of the urinary bladder (TCC) patients classified by recurrence and/or progression has demonstrated that loss of chromosome 9, as detected by FISH analysis of the pericentromeric classical satellite marker at 9q12, occurs early. A total of 105 TCCs from 53 patients were analysed in situ by two independent observers for loss of chromosome 9 using quantitative fluorescence in situ hybridization (FISH). All 53 primary tumours were evaluated for chromosomes 9, 7 and 17. Normal ranges for chromosomal copy number were defined for normal skin epidermis and bladder epithelium. Values for chromosome 9 copy number outwith the range 1.51-2.10 (mean +/- 3 x s.d. of normal values) were significantly abnormal. Twenty-five TCCs were detected with consistent monosomic scores. Of 89 TCCs, in which multiple tumour areas were analysed, 85 tumours (96%) demonstrated the same chromosome 9 copy number in all areas (2-6) analysed; only three tumours demonstrated heterogeneity for this locus. A total of 36% (12 out of 33) of patients with subsequent disease recurrence demonstrated loss of chromosome 9 in their primary and all subsequent TCCs analysed. Only a single patient (n = 20) with non-recurrent TCC showed loss of chromosome 9 (P = 0.0085). Of 53 primary tumours, eight showed significant elevation of chromosome 17. Of these patients, six demonstrated elevation in chromosome 7 copy number. No abnormalities were observed in non-recurrent patients. This study describes rapid quantitation of chromosomal copy number by FISH using a pericentromeric probe for chromosome 9 in TCC of the urinary bladder. Routinely fixed and processed material was evaluated without disaggregation. Strict quality control of FISH demonstrated that this technique was reproducible in a clinical environment and could be used to detect genetic changes relevant to patient outcome. It is proposed that loss of chromosome 9 from primary TCC of the urinary bladder identified patients at high risk of recurrence and possible progression.
authors.affiliation: Glasgow University Department of Surgery, Glasgow Royal Infirmary, UK.
authors.forename: J M
authors.initials: JM
authors.lastname: Bartlett
authors.forename: A D
authors.initials: AD
authors.lastname: Watters
authors.forename: S A
authors.initials: SA
authors.lastname: Ballantyne
authors.forename: J J
authors.initials: JJ
authors.lastname: Going
authors.forename: K M
authors.initials: KM
authors.lastname: Grigor
authors.forename: T G
authors.initials: TG
authors.lastname: Cooke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000473:pathology; D002872:Chromosome Deletion; D002886:Chromosomes, Human, Pair 17; D002897:Chromosomes, Human, Pair 7; D002899:Chromosomes, Human, Pair 9; D018450:Disease Progression; D005260:Female; D005819:Genetic Markers; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000235:genetics* / Q000473:pathology; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000473:pathology
chemical_list: D005819:Genetic Markers