A case of Li-Fraumeni syndrome diagnosed with bilateral breast cancer in the initial high-risk surveillance in a family which multi-gene panel testing was effective

Abstract

　Li-Fraumeni syndrome (LFS) is a highly penetrant cancer syndrome associated with a germline pathogenic variant of TP53, which is responsible to develop premenopausal breast cancers. According to the NCCN guideline version 2 2024 for female LFS carriers, it is recommended to take annual breast MRI and mammography. It is also considered an option to undergo bilateral risk-reducing mastectomy with genetic counseling. LFS has been mostly diagnosed by single-gene testing among patients; who were estimated high risk according to the classic criteria of LFS or Chompret criteria. However, since multi-gene panel testing has recently become more common in some countries such as the United States, it has been revealed that there are some cases of LFS with different clinical features from conventional LFS. We present a case of LFS whose relative was diagnosed with LFS by a multi-gene panel test, and who had bilateral breast cancer which were diagnosed in the first breast surveillance. We have experienced 5 cases of LFS with breast cancer in our hospital. In order to clarify the clinicopathological characteristics of breast cancer in LFS, we examined the concordance between clinicopathological factors and diagnostic criteria in the five cases.