The following is a summary of “Density of tumor-infiltrating NK and Treg cells is associated with 5 years progression-free and overall survival in resected lung adenocarcinoma,” published in the June 2024 issue of Pulmonology by Szentkereszty et al.

Surgical resection is widely regarded as curative for pulmonary adenocarcinoma, yet the variability in progression-free survival (PFS) underscores the need for a deeper understanding of the immune response’s role. This study delved into the significance of tumor-infiltrating natural killer (NK) and regulatory T (Treg) lymphocytes, pivotal immune system components, in predicting outcomes following resection. The research involved analyzing tissue samples from 115 patients with resected pulmonary adenocarcinoma, using immunohistochemistry to quantify NKp46 and FoxP3 expression for NK and Treg cells, respectively. These immune cells were predominantly located within the tumor stroma, where their densities were assessed.

NK cell density was notably associated with specific patient characteristics such as female gender, non-smoking status, and KRAS wild-type tumors, underscoring potential correlations between immune response and tumor biology. Kaplan-Meier analysis demonstrated that patients exhibiting higher densities of NK or Treg cells experienced significantly prolonged PFS and overall survival (OS). Moreover, cases characterized by high densities of both NK and Treg cells (NK^high/Treg^high) showed even more favorable outcomes regarding PFS and OS than those with lower densities.

Further analysis using multivariate Cox regression confirmed that high NK cell density independently predicted longer PFS, while high densities of both NK and Treg cells independently predicted longer OS. Notably, the NK/Treg^high combination emerged as an independent prognostic factor for PFS and OS, highlighting its potential clinical relevance.

In conclusion, these findings underscore the critical role of NK and Treg cells in the immune response against pulmonary adenocarcinoma progression post-resection. The study suggests that assessing these immune cell densities could serve as valuable prognostic markers, aiding in risk stratification and potentially guiding personalized treatment approaches to enhance patient outcomes in this context.

Source: sciencedirect.com/science/article/abs/pii/S0169500224003581