C-ERBB-2 OVEREXPRESSION IN THE DYSPLASIA CARCINOMA SEQUENCE OF BARRETTS-ESOPHAGUS

Aims-To investigate overexpression of the oncoprotein c-erbB-2 in the dysplasia/carcinoma sequence of Barrett's columnar-lined oesophagus (C LO). Methods-Immunohistochemical staining was performed using the mono clonal antibody NCL-CB-11 on formalin fixed tissue from 31 cases of Ba rrett's carcinoma, 20 cases of cancer associated dysplastic CLO, seven cases of dysplastic CLO without cancer, and 20 cases of non-dysplasti c CLO. Membranous staining was regarded as positive for c-erbB-2 overe xpression; cytoplasmic staining was recorded separately as its signifi cance is uncertain. Results-Membranous c-erbB-2 overexpression was obs erved in eight of 31 (26%) carcinomas and in none of the cases of dysp lastic CLO. Variable cytoplasmic staining was seen in four of 31 (13%) tumours and seven of 27 (26%) cases of dysplastic CLO. No staining wa s observed in non-dysplastic CLO. Conclusions-C-erbB-2 overexpression is a relatively late event in the development of some Barrett's carcin omas and is unlikely to be involved in the early stages of neoplastic transformation of CLO.