Abstract:

Objective

To study the effect of neoadjuvant chemotherapy on the expressions of Ki67 and P53 in breast cancer tissues,and analyze the relationship between the pathologic grading and Ki67 and P53 expressions.

Methods

The expressions of Ki67, P53 and other biological parameters in 40 patients with stage II and III breast cancer were examined by immunohistochemical staining before and after neoadjuvant chemotherapy. Response Evaluation Criteria in Solid Tumors and the pathological grading made in the Pathological Department of our hospital were used to assess clinically the neoadjuvant chemotherapy effect.According to the percentages of Ki67 positive and P53 positive cells patients were grouped into low and high expressions to study the correlation between response to noeadjuvant chemotherapy and different expression levels of Ki67 and P53. Chi-square test or Fisher's exact test was used for numeration data, nonparametric test for ranked data, and Spearman's rank correlation test for correlation between the response to neoadjuvant chemotherapy and the changes of Ki67 and P53 expressions.

Results

(1)The positive rates of Ki67 and P53 expressions in breast cancer tissues were 62.5%(25/40) and 40.0%(16/40), respectively, and high expression rates were 27.5%(11/40) and 15.0%(6/40), respectively. The Ki67 expression was correlated with HER-2 status (P=0.004), but independence of the age, the clinical stage and the ER condition (P ＞0. 050). The P53 expression had no relationship with general pathological factors (P ＞0. 050). (2)Patients with high expression of Ki67 were more likely responded to neoadjuvant chemotherapy than those of low expression (P=0. 049). (3)The positive expression rate of Ki67 decreased significantly after neoadjuvant chemotherapy compared to before chemotherapy(P=0.027),but there was no change of P53 (P＞0.050).(4)The changes of Ki67 was correlated with response to neoadjuvant chemotherapy(r=0.347,P=0.028), but the changes of P53 was not correlated with the response of neoadjuvant chemotherapy (P＞0.050).

Conclusions

Ki67 may be used as the maker to predict efficiency of neoadjuvant chemotherapy.

Key words: breast neoplasms, neoadjuvant chemotherapy, pathology assessment, Ki67, P53