ABSTRACT
Some malignant tumours like testicular seminomas and ovarian dysgerminomas or medullar carcinoma of the breast, present an unusually lympho-histiocytic (TIL) rich stroma. Many reports have concluded that the prognosis for these patients is correlated with the intensity of TIL. Recently, some analyses consider that tumour-host interactions have a significant prognostic role in many other neoplasms. The presence of TIL may be a sign of less aggressive behaviour of some epithelial neoplasm like gastro-intestinal, pulmonary, mammary, urinary or cutaneous carcinomas (Wilson et al.). The aim of this study is a morphological and immunohistochemical (IHC) characterisation of the lympho-histiocytic populations of TIL in some gastro-intestinal and mammary carcinomas. The two localisation were chosen for their different contact with the exogene antigens and their possible different type of host's immune response.