Objective To study the relationships between host immune function in the tumor microenvironment (TME) and early-stage lung cancer progression.

Methods A total of 216 patients with early-stage lung cancer admitted to Zhumadian Central Hospital between February 2020 and April 2023 were included to analyze immune cell presence in cancer and adjacent tissues. The patients were assigned into a relapse group (41 cases) and a non-recurrence group (175 cases) based on their relapse status. Baseline data and immune cell expression in the two groups were compared to analyze the influence and predictive value of immune cell prevalence on lung cancer recurrence.

Results The proportion of CD56⁺ natural killer (NK) cells was lower in cancer tissues than that in adjacent tissues. The infiltration rates of CD68⁺ tumor-associated macrophages (TAMs) and CD163⁺ TAMs, as well as the proportions of CD4⁺ and CD8⁺T cells, were higher in adjacent tissues than in cancerous tissues (P<0.05). In the recurrence group, the maximum tumor diameter, proportion of patients with micro-papillary structures, CD68⁺ TAM and CD163⁺ TAM infiltration rates, and CD8⁺T cell proportion were higher than those in the non-recurrent group, while the CD56⁺ NK cell positive rate was lower (P<0.05). After correction, CD56⁺NK positivity, elevated CD68⁺ TAM and CD163⁺ TAM infiltration, and CD8⁺T cell proportion were independent factors associated with early-stage lung cancer recurrence (P<0.05). The AUC for predicting early- stage lung cancer recurrence using CD56⁺NK positivity+high CD68⁺ TAM and CD163⁺ TAM infiltration + proportion of CD8⁺T cells was 0.949, which was higher than that of each individual immune marker (P<0.05).

Conclusions Host immune function in the TME in patients with early lung cancer correlates with disease progression. The combination of high CD56⁺NK⁺, CD68⁺ TAM infiltration, high CD163⁺ TAM infiltration, and CD8⁺ T-cell ratio can improve prediction efficiency for early lung cancer recurrence.