Lung adenocarcinoma manifesting as subsolid nodule potentially represents tumour in the equilibrium phase of immunoediting.

PHASE equilibrium; KILLER cells; LUNGS; T cells; NATURAL immunity

Lung adenocarcinomas manifesting as subsolid nodules (SSN‐LUADs) possess distinct dormant behaviour. This study was designed to compare the immune landscapes of normal lungs (nLungs), SSN‐LUADs and LUADs manifesting as solid nodules (SN‐LUADs) so as to better understand the status of anti‐tumour immunity in SSN‐LUADs. Mass cytometry by time‐of‐flight analysis was performed on 299, 570 single cells from nLung, SSN‐LUAD and SN‐LUAD tissues. The immune cells were identified by phenotype, and the percentages of different immune cell subclusters were compared between SSN‐LUADs, SN‐LUADs and nLungs. Elevated percentage of CD8+ T cells were identified in SSN‐LUADs compared with in nLungs and SN‐LUADs. Elevated CD56bright NK cells and decreased CD56dim NK cells were identified in both SSN‐LUADs and SN‐LUADs compared with in nLungs. The immune landscape of SSN‐LUAD fits the theory of equilibrium phase of immunoediting, thus functional adaptive anti‐tumour immunity but impaired innate anti‐tumour immunity potentially contributes to the maintaining of its dormant behaviour. [ABSTRACT FROM AUTHOR]