Li-fraumeni syndrome

Abstract

Li-Fraumeni syndrome (LFS) is a classic cancer predisposition disorder that is commonly associated with germline mutations of the p53 tumor suppressor gene. Examination of the wide spectrum of adult-onset and childhood cancers and the distribution of p53 mutations has led to a greater understanding of cancer genotype-phenotype correlations. However, the complex LFS phenotype is not readily explained by the simple identification of germline p53 mutations in affected individuals. Recent work has identified genetic events that modify the LFS phenotype. These include intragenic polymorphisms, mutations/polymorphisms of genes in the p53 regulatory pathway, as well as more global events such as aberrant copy number variation and telomere attrition. These genetic events may, in part, explain the breadth of tumor histiotypes within and across LFS families, the apparent accelerated age of onset within families, and the range of clinical outcomes among affected family members. This review will examine the clinical and genetic definitions of LFS and offer insight into how lessons learned from the study of this rare disorder may inform similar questions in other familial cancer syndromes.

Keywords: Li-Fraumeni syndrome; cancer predisposition; germline p53 mutations.

Conflict of interest statement

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.

Pedigree of a family with Li-Fraumeni syndrome. Filled circles/squares represent affected members; slashes represent deceased family members. Numbers represent age at diagnosis. BB = bilateral breast cancer; CNS = brain tumor; BR = unilateral breast cancer; LK = leukemia; CPC = choroid plexus carcinoma; RMS = rhabdomyosarcoma; OS = osteosarcoma.

Figure 2.

Relative frequency of germline mutations in p53 by codon adjacent to the primary structure of the p53 protein. TAD = transactivation domain; PRR = proline-rich region; DBD = DNA binding domain; TET = tetramerization domain; REG = regulatory domain. Adapted from the International Association for Research on Cancer (IARC) database (Revision 14, November 2009).