The Authors evaluate new possible models for the staging of colorectal cancer based on clinico-morphological, histo-pathological and bio-immunological parameters. Particularly, they evaluate the possibility of studying host's immunological response against tumor spread by the examination of the "in situ" cellular responses. This study was performed by cytotoxic test and immunohistochemical evaluation of the lymphocytes. The latter seems to give better results compared to the first in the evaluation of the host's immunological response.