Correlation between Ki67 and breast cancer prognosis.

Background: Ki67 is an immunohistochemical proliferation marker in many types of cancer and has been widely studied among breast cancer patients mostly through retrospective studies.

Methods: The MEDLINE/PubMed database was searched for publications with the medical subject heading 'Ki 67' and the key words 'breast', 'cancer', and 'prognosis'. We restricted our search to articles published until 2012.

Results: In this review, we included 78 articles and abstracts that were accessible and available in English. An effort to further explain the role of Ki67 in the prognosis of breast cancer has been made.

Conclusions: The debate on the prognostic role of Ki67 in breast cancer is still open, although most of the studies have established a relation between Ki67 and overall and disease-free survival. Further research should be made in order to establish Ki67 as a standard prognostic marker in breast cancer.