Changes of CD4 T-cell subsets after radiofrequency ablation in lung cancer and its significance.

Aims: To analyze the changes of CD4+ T-cell subsets following radiofrequency ablation (RFA) in lung cancer and the impact of RFA on the antitumor immunity.

Subjects And Methods: Flow cytometry was employed to detect CD4+ T-cell subsets in the peripheral blood from 45 healthy controls and 45 lung cancer patients before and after RFA. The correlation between CD4+ T-cell subsets and the clinical characteristics was discussed by comparing the results between different groups.

Results: Compared with the healthy controls, the lung cancer patients showed a decline in Th1 cells, but higher Th2, Th17, and Treg cells (P < 0.05). Th1 cell level and Th1/Th2 cell ratio were significantly lower for stage III/IV than Stage I/II and also lower for patients with Karnofsky Performance Status (KPS) score <60 than ≥ 60 (P < 0.05). The levels of Th2, Th17, and Treg cells were much higher for patients with Stage III/IV and KPS score <60 (P < 0.05). After 2 weeks of RFA, the level of Th1 cells and Th1/Th2 cell ratio increased, while the levels of Th2, Th17, and Treg cells declined (P < 0.05). For lesions with ablation volume ≥ 70%, the level of Th1 cells and Th1/Th2 cell ratio increased, whereas the levels of Th2, Th17, and Treg cells declined dramatically (P < 0.05).

Conclusions: The level of Th1 cells declined in lung cancer patients, especially for patients with Stage III/IV and KPS score <60. After RFA, the level of Th1 cells and Th1/Th2 increased, whereas the levels of Th2, Th17, and Treg cells declined, indicating an improvement of antitumor immunity. The changes were more prominent for lesions with ablation volume ≥ 70%.