Tumeh et al. found in biopsy samples that CD8+ T cell density at the edge of invasive tumours in patients with liver metastasis was lower than that in patients without liver metastasis (liver metastasis + group, n = 547 ± 164.8; Liver metastases–group, n = 1441 ± 250.7; P & lt; 0.016), and this was associated with decreased ICI response rate and shortened PFS in patients with liver metastases with NSCLC [15]. This evidence concerns the gene CD8A and non-small cell lung carcinoma.