EXPRESSION OF ACIDIC FIBROBLAST GROWTH-FACTOR IN BARRETTS-ESOPHAGUS AND ASSOCIATED ESOPHAGEAL ADENOCARCINOMA

Objective: adenocarcinoma of the esophagus is generally attributed to the neoplastic transformation of intestinal metaplastic lesions (Barre tt's esophagus), On the basis of our preliminary data that showed sign ificant acidic fibroblast growth factor mRNA and protein expression in adenocarcinoma of the esophagus, we studied expression of fibroblast growth factor in esophageal adenocarcinoma and its precursor lesions, intestinal metaplasia, low-grade dysplasia, and high-grade dysplasia. Fibroblast growth factor belongs to a family of polypeptides that are involved in differentiation and cellular proliferation, Methods: We ex amined 30 esophagectomy specimens that were resected for adenocarcinom a (n = 27) and high-grade dysplasia (n = 3), After confirmation of the diagnosis by routine light. microscopy, the index lesions (invasive c arcinomas) and adjoining Barrett's mucosa were evaluated with a monocl onal antibody against human acidic flbroblast growth factor, The resul ts art: expressed with the use of an immunoreactive score that allows distinction between weak, moderate, and strong immunoreactivity. Resul ts: Adenocarcinoma demonstrated a moderate-to-strong mean immunoreacti ve score of 8, In contrast, high-grade dysplasia demonstrated a weak-t o-moderate mean score of 4.5, which was significantly different (p < 0 .05), Intestinal metaplasia and low-grade dysplasia displayed even wea ker expression of fibroblast growth factor, with a negligible immunore active score less than 1 (p < 0.005). Seventy-five percent of evaluabl e cases demonstrated an increasing degree of fibroblast growth factor expression in the spectrum of lesions ranging from metaplasia to dyspl asia and carcinoma, Conclusions: These data indicate that in patients with adenocarcinoma arising in association with Barrett's esophagus, f ibroblast growth factor is generally sequentially accumulated in the p rogression from metaplasia to neoplasia. This progression may affect f uture investigation into the role of fibroblast growth factors in tumo rigenesis and, possibly, the application of fibroblast growth factor i mmunohistochemistry to diagnosis.