title: Ki-67 labeling index affects tumor infiltration patterns of lung squamous cell carcinoma.
abstract: Ki-67 is a nuclear protein that is expressed during the G1, S, G2 and M phases of the mitotic cell cycle. A previous study categorized tumor infiltration patterns (INF), of which INFc indicated cancer nests exhibiting infiltrative growth and an unclear boundary between tumor tissue and surrounding healthy tissue. The present study used the Ki‑67 labeling index (Ki‑67 LI) as an indicator of cell proliferation, in order to examine the factors affecting INF in lung squamous cell carcinoma (SqCC). SqCC specimens (89) were classified into two groups: High‑grade cell proliferation (Ki‑67 LI ≥30%) and low‑grade cell proliferation (Ki‑67 LI <30%). However, a high Ki‑67 LI was significantly associated with cases that had an INFc component [INFc(+); P=0.03]. Univariate analyses indicated that INFc(+) was a predictor of venous invasion [P=0.032; odds ratio (OR), 2.615; 95% confidence interval (95% CI), 1.085‑6.305], scirrhous stromal type (P<0.001; OR, 6.462; 95% CI, 2.483‑16.817) and high Ki‑67 LI (P=0.018; OR, 12.543; 95% CI, 1.531‑102.777). Multivariate logistic analyses indicated that high Ki‑67 LI was the strongest predictor of INFc(+) (P=0.028; OR, 8.027; 95% CI, 1.248‑51.624). In conclusion, high‑grade cell proliferation activity may contribute to aggressive infiltrative growth of lung SqCC.
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Masuda
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Ryota
authors.initials: R
authors.lastname: Masuda
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Matsuzaki
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Imamura
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Naohiro
authors.initials: N
authors.lastname: Aruga
authors.affiliation: Department of Pathology and Bioscience, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036‑8562, Japan.
authors.forename: Makiko
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Department of Pathology and Bioscience, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036‑8562, Japan.
authors.forename: Sadaki
authors.initials: S
authors.lastname: Inokuchi
authors.affiliation: Department of Pathology and Bioscience, Hirosaki University Graduate School of Medicine, Hirosaki, Aomori 036‑8562, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kijima
authors.affiliation: Department of General Thoracic Surgery, Tokai University School of Medicine, Isehara, Kanagawa 259‑1193, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Iwazaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008168:Lung / Q000473:pathology*; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology*
chemical_list: D019394:Ki-67 Antigen