Definition:

Li-Fraumeni syndrome (LFS) is a familial clustering of early onset tumors including sarcomas, breast cancers, brain tumors and adrenocortical carcinomas (ADR). Initially considered as a rare syndrome, LFS and its variants are increasingly recognized as one of the most frequent and diverse forms of predisposition to cancer. Most cases identified and characterized to date are associated with dominantly inherited germ line mutations in the tumor suppressor gene TP53 (p53). In a subset of non-p53 patients with LFS, CHEK2 has been identified as another predisposing locus. LFS is diagnosed on the basis of the confirmed clinical diagnostic criteria.