Peculiarities of proliferative activity of non-small cell lung cancer in case of tumor spread through air spaces

Aim. To study the proliferative activity of non-small cell lung cancer with tumor spread through air spaces.
Materials and methods. The study included 88 patients with stage IA-IIIA non-small cell lung cancer. The operative material was evaluated. Histologic and immunohistochemical examination was performed according to the standard technique. Antibodies to Ki67 (clone SP6, Cell Marque) were used. On digitized preparations using automated system Pannoramic MIDI with software Slide Viver V2.8. and multi-module platform Quant Center (3D HISTECH, Hungary) we counted the percentage of cells with positive nuclear expression of Ki67 in the tumor as a whole and in the area of spreading. Statistical processing was performed using the STATISTICA 10.0 software package. Differences at p < 0.05 were considered statistically significant.
Results. The percentage of Ki67 expression in the tissue of the primary tumor node was higher in cases with the presence of tumor spread through air spaces, including stage IA lung adenocarcinoma. The percentage of Ki67 expression in the area of air space spread of the tumor was higher compared to the percentage of expression in the tumor as a whole. Higher proliferative activity in the zone of tumor air space spread was observed in cases with extensive spread compared to cases with a limited variant of air space spread.
Conclusion. The results obtained complement the existing data on the mechanisms of tumor spread through air spaces as a form of invasive growth and one of the variants of tumor progression characteristic of lung cancer.

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