Comparative study of two complementary proliferation markers in 200 breast carcinomas: Ki67 and mitotic index.

BACKGROUND: The evaluation of the proliferation in the mammary carcinomas provides useful prognostic and predictive information for subsequent management. The purely morphological evaluation of proliferative activity was represented by the evaluation of mitotic index. New analytical methods were gradually developed and performed. Among these methods, evaluation of Ki67 by immunohistochemistry is particularly interesting. Its expression is significantly increased in the cell cycle.

AIM: To correlate the mitotic index as a classic method of assessing cell proliferation and Ki 67 proliferation index detected by immunohistochemistry to identify the most reliable proliferative marker.

METHODS: We studied 200 patients with invasive ductal carcinoma breast over a period of 12 months of 2014. We identified in each case the SBR grade, Ki67 proliferation index and the mitotic index. Correlation between the two parameters was identified using the Spearman test. A result is considered significant when p < 0.01. The distribution of these markers by SBR gradewas studied using the ANOVA method.

RESULTS: Ki67 is significantly correlated to the mitotic index. Although these two methods are dependent, Ki67 is the most sensitive and bonded to SBR grade. Determination of Ki67 provides interesting information that could replace the mitotic account. It provides reliable and reproducible data that can be incorporated into a prognostic score.

CONCLUSION: Ki67 is a more efficient marker mitotic index, reflecting the cell proliferation.