The CD4/CD8 ratio was still higher in sarcoidosis than lung cancer even when we compared patients whose ages were 60–80 years (sarcoidosis 9.31 ± 4.15, lung cancer 1.70 ± 1.34, mean ± SD) (p < 0.03, Mann-Whitney U-test) (S2 Fig). Here, CD8A is linked to lung carcinoma.