CLDN3 and neoplasm: Hereby, especially the claudins 3, 4, 6 and 18.2 have become the main focus of oncological research since their expression across different tumor entities is a necessary prerequisite for a potential tumor-agnostic, pan-cancer treatment within the area of personalized medicine.4–7 Scilicet, to date, at least some family members of the total 26 human claudin proteins have been tested in a gyneco-oncological context, whether for the detection of precancerous cervical lesions or the potential risk stratification of solid non-gastric neoplasms.3,6,8,9