PD-L1+ CTCs were identified in 8.2% of early-stage patients, 54.5% of locally advanced and 93.8% of metastatic patients. HCC patients with PD-L1+ CTCs had favorable treatment responses when receiving anti-PD-1 therapy. Winograd et al., 2020 (94). The gene discussed is PDCD1; the disease is hepatocellular carcinoma.