The Study On The Correlation Between Ki67 And Prognosis Of Non-small Cell Lung Cancer

Background and Objective: Ki67 level is closely related to tumor cell proliferation. Our study explored the relationship of Ki67 and the prognosis of stage II-IIIA non-small cell lung cancer with the aim toprovide guidance for clinical diagnosis and treatment.Methods: This study collected the tumor tissue specimens of all the patients who were pathologically diagnosed with stage II-IIIA non-small cell lung cancer after radical surgery in our hospital(Zhangzhou Affiliated Hospital of Fujian Medical University) from Jan 2011 to Dec 2011. Clinical data of all the patients were collected by reviewing medical records.Ki-67 protein in tumor tissues were tested by immunohistochemistry, Each specimen was assigned as Ki67 positive or Ki67 negative.The relationship of Ki67 with patients’ clinical features in- cluding agegender,smoking history,T category,N category, stage, histologic grade and pathological type were analyzed.Univariate and multivariate analysis were conducted to explore the correlation between Ki67 and overall survival.Results:1.95 patients were included in the study with an average age of 47.5 years.55 were male,and 40 were female. 2. The expression of Ki67 in non-small cell lung cancer was high. Ki67 positive rate in smoking group was 54.9%, and in non-smoking group was 16.7%, the difference between the two groups was significant(p < 0.05).The Ki67 positive rate in non- elderly group(less than 60 years old)and elderly group(over than 60 years old) was 57.8% and 19.3% respectively. There was significant difference between the two groups(p < 0.05). The Ki67 positive rates in male or female group were similar(52.7% versus 35.0%(p > 0.05). 3. The positive rate of Ki67 in T1,T2,T3 category patients was 0%, 37.5%, and 71.8%,respectively,and there was significant difference between them(P <0.05). The positive rate of Ki67 in N0,N1,N2 category patients was 0, 4.4%,62.0%, respectively,and the difference was statistically significant(p <0.05). The positive rate of Ki67 was 22.0% in stage II patients and63.0% in stage IIIA patients(P < 0.05). The positive rate of Ki67 in patients with histologic grade Ⅲ/Ⅳ was higher than those with histologic gradeⅠ/Ⅱ(P < 0.05).The positive rates of Ki67 in patients with different pathological types were similar. 4. Univariate and multivariate analysis indicated that the overall survival of non-small cell lung cancer was associatd with the diameter of tumor,lymph node metastasis,TNM stage,histological grade and the expression of Ki67.High expression of ki67 was closely related to poorprognosis.Conclusions:1.Ki67 expression in non-small cell lung cancer tissue is high, and the expression rate is associated with age, smoking. 2. Patients with larger tumor, more lymph node metastases or higher histological grade have higher Ki67 expression rate. 3. Ki67 might be an independent prognostic factor for survival in patients with stage II-IIIA non-small cell lung cancer.