Similarly, no difference was observed in hyperplasia (4–6 weeks) and adenoma/MIN or advanced‐premalignant‐stage (6–8 weeks) tissue pathology between IL‐22+/+ or IL‐22−/−/PyMT mice as primary tumors appeared to be confined by basement membrane with florid epithelial cell proliferation in both group of mice (Fig. 2A). Here, IL22 is linked to adenoma.