Quantitative assessment of Ki67 expression in correlation with various breast cancer characteristics and survival rate; cross sectional study

BACKGROUND: Ki-67 is a cellular proliferative index that has variable expression during cell cycle. The absence of Ki-67 in the quiescent tissues and its expression in the proliferating cells had linked its possible role in the proliferative capacity of the tissues. MATERIALS AND METHODS: This retrospective study included 314 patients with breast cancer who underwent various types of breast surgeries. Analyzed was done to find any possible correlation between the level of Ki67 and various patient and tumor characteristics and the survival rates. RESULTS: The mean age was 48.73 years, the overall survival was 30.77 months, 90.8% of the patients were alive and 8.3% died from breast cancer. In 85.67% no recurrence was reported and 5% had local and axillary recurrences, the commonest sites of metastases were bones and the vertebrae (2.2% and 1.9%) respectively. The mean size of the tumor was 34.39 mm and the mean number of the positive axillary nodes was 4. The expression of Ki67 was around 5–10% in the majority of patients, the mean expression was 28.54%. There was significant correlation between the level of Ki67 and the histopathological grade of the tumor, p value 0.003, and there was no significant correlation with other variables. There was no relation between the overall survival and the Ki67 level. CONCLUSION: Ki67 is correlated with the grade of the tumor, and is not a predictor for the survival of breast cancer patients. It may predict aggressive behavior of the tumor and higher histopathological grades.