A systematic scoping review on natural killer cell function in colorectal cancer.

PURPOSE: Natural Killer (NK) cells are a vital part of immune surveillance and have been implicated in colorectal cancer development and prognosis. This systematic review aims to distil the literature on NK cells as it relates to colorectal cancer. METHODS: All published studies over 10 years relating to NK cells and colorectal cancer were reviewed. All studies publishing in English, searchable via pubmed or through reference review and reporting directly on the nature or function of NK cells in colorectal cancer patients were included. Outcomes were determined as alterations or new information regarding NK cells in colorectal cancer patients. RESULTS: Natural killer cells may be implicated in the development of colorectal cancer and may play a role in prognostication of the disease. NK cells are altered by the treatment (both surgical and medical) of colorectal cancer and it seems likely that they will also be a target for manipulation to improve colorectal cancer survival. CONCLUSIONS: NK cell morphology and function are significantly affected by the development of colorectal cancer. Observation of NK cell changes may lead to earlier detection and better prognostication in colorectal cancer. Further study is needed into immunological manipulation of NK cells which may lead to improved colorectal cancer survival.