A significant proportion of positive GCs and GECs from our dataset showed low prevalence of CLDN18 staining (2+ and 3+ intensity in 1–49% of tumor cells) while high CLDN18 expression (2+ and 3+ intensity in ≥50% of tumor cells) was found in 158/350 (45.1%) cases and 117/350 (33.4%) patients presented at least 75% of the cancer cells stained for CLDN18. The gene discussed is CLDN18; the disease is cancer.