Aims: To study the expression of MUC1 and MUC4 mucins in Barrett-associated oesophageal adenocarcinoma and coexisting lesions of the carcinogenic sequence (normal mucosa, metaplasia, dysplasia) if present, and to investigate their prognostic significance.
Methods: The expression profiles of MUC1 and MUC4 were investigated by immunohistochemistry in tissue samples obtained from consecutive patients with primary surgically resected lower third oesophageal adenocarcinoma (OA) between 1997 and 2002. Histopathological parameters, recurrence and long-term survival were correlated with the number of cells stained.
Results: All 52 patients exhibited OA, with 25 patients (48.1%) having associated Barrett oesophagus lesions (metaplasia or/and dysplasia). MUC1 and MUC4 were expressed in 52 and 41 of the 52 patients with adenocarcinoma (100% and 78%), respectively. All samples expressed MUC1 strongly. The prevalence of MUC4 staining was significantly decreased in metaplasia compared with normal mucosa (53% versus 92%, p<0.001). No correlation was found between the level of MUC1 or MUC4 expression in OA and histopathological variables, recurrence or survival.
Conclusions: MUC1 and MUC4 are strongly expressed in OA. The results do not support a role for these two membrane-bound mucins as either a phenotypic or a prognostic marker for the development of Barrett OA. There are several other membrane-bound mucins that have not yet been evaluated in this situation.