Expression of CD44v6 but not E-cadherin or beta-catenin influences prognosis in primary pulmonary adenocarcinoma

Primary pulmonary adenocarcinoma was studied, looking for relationships bet ween the expression of cell adhesion molecules (CAMs) E-cadherin, beta -cat enin and CD44v6, and clinicopathological tumour parameters and patient post -operative survival. Formalin-fixed, paraffin-embedded tissue from 120 prim ary lung adenocarcinomas, including 23 poorly differentiated tumours, 17 of probable bronchial origin, and 29 with a prominent bronchioloalveolar patt ern, together with nodal metastatic tumour from 34 of these patients was st ained using monoclonal antibodies and immunohistochemistry. Sections were s cored either high level (>10% cells positive) or low level (<10% positive). High level expression of CD44v6 was retained in 28.4% (34/120) of tumours, while high levels of E-cadherin (57.5%, 69/120) and <beta>-catenin (80.8%, 97/120) were more frequent. For all CAMs, staining levels did not correlat e with nodal status, stage or tumour type. The apical or basal staining see n in normal bronchial and alveolar epithelium was often seen in papillary, glandular, and bronchioloalveolar areas of tumour, while solid invasive tum our more often showed pericellular staining. When the staining for each CAM in 34 nodal metastases was compared with that in the corresponding primary tumour, a high degree of concordance was found, with no tendency for metas tases to show less staining than the primary tumour. Expression of E-cadher in and beta -catenin in the primary tumour had no influence on post-operati ve survival, but patients whose tumours had low level CD44v6 expression had a poorer post-operative survival than those with high levels of CD44v6 (p = 0.0014 for all patients, p = 0.0012 for stage I patients only). In primar y pulmonary adenocarcinoma, the levels of expression of E-cadherin, beta -c atenin, and CD44v6 are not associated with lymph node metastases or tumour stage but the staining pattern is associated with tumour morphology. Low le vels of CD44v6 expression predict a poor post-operative survival, independe ntly of stage, while there is no such relationship with the expression of E -cadherin or beta -catenin. Copyright (C) 2000 John Wiley & Sons, Ltd.