RT Journal Article SR Electronic T1 E-cadherin immunoexpression patterns in the characterisation of gastric carcinoma histotypes JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 635 OP 639 DO 10.1136/jcp.2010.076026 VO 63 IS 7 A1 P R Almeida A1 V A Ferreira A1 C C Santos A1 F D Rocha-Filho A1 R R Feitosa A1 E A A Falcão A1 B K Cavada A1 R A Ribeiro YR 2010 UL http://jcp.bmj.com/content/63/7/635.abstract AB Aims E-cadherin, the main epithelial intercellular adhesion molecule, is abnormally expressed in many cancer types, including gastric carcinoma, which is the second leading cause of cancer death worldwide. The aim of this study was to contribute to the characterisation of gastric carcinoma histotypes based on a new approach to E-cadherin immunoexpression.Methods 97 gastric tumour samples obtained from the files of the Hospital of Cancer/Cancer Institute of Ceará, Brazil, were histologically analysed and classified as intestinal (n=40), diffuse (n=34), mixed (n=16) or unclassified (n=7) carcinomas. Immunohistochemistry was performed on the tissue microarray sections. Scores were applied according to the system of Jawhari: 0, no staining; 1, cytoplasmic staining; 2, cytoplasmic and membranous staining in the same case; 3, normal membranous immunoexpression; abnormal patterns: scores 0, 1 and 2; normal pattern: score 3. Jawhari scores were then evaluated utilising another approach: the absence of membranous expression scores (0 and 1) versus the presence of membranous expression (scores 2 and 3).Results A significant association between membranous expression of E-cadherin and the intestinal histotype (36/40 (90%), and 28/41 (68%) for other histotypes) was found, while diffuse carcinomas were related to the absence of membranous expression. A very strong and peculiar relationship was observed between cytoplasm-exclusive E-cadherin expression (score 1) and the diffuse component of mixed tumours (11/16 (69%)).Conclusions E-cadherin immunoexpression patterns help us to characterise gastric carcinoma histotypes. The presence or absence of membranous staining is the most valuable criterion in evaluating E-cadherin expression. Mixed tumours show a characteristic E-cadherin cytoplasmic expression in gastric carcinomas.