Morphological and immunohistochemical features of tumor infiltrating lymphocytes (TIL) in carcinomas. Note I.

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.