NTHL1‐associated polyposis is an autosomal recessive condition where individuals harbouring biallelic variants in NTHL1 have been reported with a variety of different cancers.28, 29, 30, 31, 32 This is the first case of this same pathogenic variant being observed in a patient with a pancreatic NET and breast cancer. The gene discussed is NTHL1; the disease is breast cancer.