MORPHOLOGICAL FEATURES OF THE PARENHYMAL-STROMAL INTERACTION ZONE IN LUNG CANCER WITH EPITHELIAL-MESENHYMAL TRANSITION

The parenhymal-stromal interaction zone was studied in 35 cases of nonsmall cell lung cancer with epithelial-mesenhymal transition using histological, histochemical and immunohistochemical techniques, in particular, using , epithelial, smooth muscle and connective tissue markers. Signs of increased activity in the stroma, characterized by accumulation of glycosaminoglycans and increasing α- smooth muscle actin expression, were often (48.6%) detected in the parenhymalstromal interaction zone. It was accompanied by the reduction of epithelial markers in the parenchyma of tumor in that area in 14 cases (40%), and by the appearance of connective tissue marker vimentin in 5 cases. Detected changes emphasise the importance of mutual influence of tumor parenchyma and its microenvironment in the development of epithelial-mesenhymal transition.