In another study conducted in a Korean patient cohort with UICC stage IV colon cancer, including 21 patients with PM and 58 with liver metastases, a high CD8+ TILs density in the primary tumor, but not in the metastatic tissue (liver and lung together) had a beneficial impact on OS (log-rank test P = 0.017 and 0.232, respectively). The gene discussed is CD8A; the disease is malignant colon neoplasm.