Hereditary lobular breast cancer is a rare inherited cancer predisposition associated with pathogenic CDH1 (gene)germline mutations, and without apparent correlation with the hereditary diffuse gastric cancer syndrome. Research studies identified novel CDH1 germline variants in women with diagnosed lobular breast cancer (in invasive and/or in situ histotype) and without any family history of gastric carcinoma. Firstly, in 2018 Giovanni Corso et al. defined this syndrome as a new cancer predisposition and the Authors suggested additional clinical criteria to testing CDH1 in lobular breast cancer patients.[1]
In 2020, the International Gastric Cancer Linkage Consortium recognized officially that the hereditary lobular breast cancer is a possible independent syndrome.[2] To date, there are reported about 40 families clustering for lobular breast cancer and associated with CDH1 germline mutations but without association with diffuse gastric cancer. Other recent studies demonstrated a possible correlation between hereditary lobular breast cancer and gastric cancer risk.[3][4]