CD38 and colorectal carcinoma: Compared with those in the healthy control group, double-negative T (DNT) lymphocytes (% of T cells) were significantly lower in the CRC group (4.0 [2.4–6.5] vs. 5.5 [3.6–7.6], P = 0.018), whereas CD8+CD38+ activated T cells (% of Tc) were significantly higher (10.3 [6.6–16.6] vs. 5.9 [4.6–10.5], P < 0.001) (Fig. 1A).