Clinicopathological and molecular characterization of gastroesophageal junction (GEJ) adenocarcinoma before age of 40 years

Ruffato, Alberto (2007) Clinicopathological and molecular characterization of gastroesophageal junction (GEJ) adenocarcinoma before age of 40 years, [Dissertation thesis], Alma Mater Studiorum Università di Bologna. Dottorato di ricerca in Scienze pneumo-cardio-toraciche di interesse medico e chirurgico, 19 Ciclo. DOI 10.6092/unibo/amsdottorato/458.
Documenti full-text disponibili:
[img]
Anteprima
Documento PDF (English) - Richiede un lettore di PDF come Xpdf o Adobe Acrobat Reader
Download (552kB) | Anteprima

Abstract

Gastroesophageal junction (GEJ) adenocarcinoma are uncommon before age of 40 years. While certain clinical, pathological and molecular features of GEJ adenocarcinoma in older patients have been extensively studied, these characteristics in the younger population remain to be determined. In the recent literature, a high sensitivity and specificity for the detection of dysplasia and esophageal adenocarcinoma was demonstrated by using multicolor fluorescence in situ hybridization (FISH) DNA probe set specific for the locus specific regions 9p21 (p16), 20q13.2 and Y chromosome. We evaluated 663 patients with GEJ adenocarcinoma and further divided them into 2 age-groups of <or= 40 and >or= 50 years, rispectively. FISH with selected DNA probe for Y chromosome, locus 9p21 (p16), and locus 20q13.2 was investigated with formalin fixed and parassin embedded tissue from surgical resections of 17 younger and 11 older patients. Signals were counted in > 100 cells with each given histopathological category. The chromosomal aberrations were then compared in the 2 age-groups with the focus on uninvolved squamous and columnar epithelium, intestinal metaplasia (Barrett's mucosa), glandular dysplasia, and adenocarcinoma. Comparisons were performed by the X2 test, Fisher's exact test, Student's t-test and Mann-Whitney U-test as appropriate. Survival was estimated by the Kaplan-Meier method with univariate analysis by the log-rank. Significance was taken at the 5% level. There was no difference in the surgical technique applied in both age groups and most patients underwent Ivor Lewis esophagectomy. Among clinical variables there was a higher incidence of smocking history in older patient group. We identified a progressive loss of Y chromosome from benign squamos epithelium to Barrett's mucosa and glandular dysplasia, and, ultimately, to a near complete loss in adenocarcinoma in both age groups. The young group revealed significantly more losses of 9p21 in both benign and neoplastic cells when compared to the older patients group. In addition, we demonstrated an increase in the percentage of cells showing gain of locus 20q13.2 with progression from benign epithelium through dysplasia to adenocarcinoma with almost the same trend in both the young and the older patients. When compared with the older age-group, younger patients with GEJ adenocarcinoma possess similar known demographics, environmental factors, clinical, and pathologic characteristics. The most commonly detected genetic aberrations of progressive Y chromosomal loss, 9p21 locus loss, and 20q13 gains were similar in the younger and older patients. However the rate of loss of 9p21 is significantly higher in young patients, in both the benign and the neoplastic cells. The loss of 9p21, and possibly, the subsequent inactivation of p16 gene may be one of the molecular mechanisms responsible for the accelerated neoplastic process in young patients.

Abstract
Tipologia del documento
Tesi di dottorato
Autore
Ruffato, Alberto
Supervisore
Co-supervisore
Dottorato di ricerca
Ciclo
19
Coordinatore
Settore disciplinare
Settore concorsuale
Parole chiave
adenocarcinoma esofago barrett giunzone esofago-gastrica fluorescence in situ hybridization FISH
URN:NBN
DOI
10.6092/unibo/amsdottorato/458
Data di discussione
26 Marzo 2007
URI

Altri metadati

Statistica sui download

Gestione del documento: Visualizza la tesi

^