Ki-67 immunostaining and other prognostic factors including tobacco smoking in patients with resected nonsmall cell lung carcinoma.
BACKGROUND
To estimate the effectiveness of expression of the tumor proliferative marker Ki-67 antigen (Ki-67) as a postoperative prognostic marker, the authors analyzed Ki-67 expression and its correlation with postoperative survival and other clinicopathologic factors, including preoperative smoking habits, in patients with resected nonsmall cell lung carcinoma (NSCLC).


METHODS
A total of 156 patients with resected NSCLC at the study institution were investigated. Postoperative survival rates were estimated based on demographic and clinicopathologic factors, including Ki-67 expression and preoperative tobacco smoking habits.


RESULTS
The overall postoperative 5-year survival rate in patients with high Ki-67 labeling indices (>/= 20%) was 39.6% compared with 67.7% in patients with low Ki-67 labeling indices. This finding was significant for all resected cases and for each pathologic disease stage (P < 0.05). The postoperative 5-year survival rate in patients with a history of heavy smoking (>/= 30 pack-years) was 47.6% compared with 62.5% for other patients (P = 0.027). This result was especially significant in patients with International Union Against Cancer Stage I disease and in patients with nonsquamous cell carcinoma (P < 0.03). The authors also observed a positive correlation between the Ki-67 labeling index and preoperative smoking habits (P = 0.0002). Multivariate analysis demonstrated that lymph node involvement, tumor differentiation, and Ki-67 labeling index were significant prognostic factors in NSCLC (P < 0.01).


CONCLUSIONS
Tumor Ki-67 expression is a strong prognostic factor in NSCLC, especially adenocarcinoma. It may be hypothesized that tobacco mutagenicity may play a role in the growth and extension of NSCLC, which is one of the major impediments to postoperative survival in patients with a history of heavy smoking.
Shiba
M
M
Department of Surgery, Institute of Pulmonary Cancer Research, Chiba University School of Medicine, Chiba, Japan.
Kohno
H
H
Kakizawa
K
K
Iizasa
T
T
Otsuji
M
M
Saitoh
Y
Y
Hiroshima
K
K
Ohwada
H
H
Fujisawa
T
T
D000368:Aged; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D002471:Cell Transformation, Neoplastic; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008175:Lung Neoplasms / Q000276:immunology* / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012907:Smoking / Q000009:adverse effects*; D016019:Survival Analysis
D019394:Ki-67 Antigen