Molecular Pathology of Thymic Epithelial Tumors

There is limited understanding of the molecular pathogenesis of thymic epithelial tumors challenging the development of targeted therapies. These tumors exhibit chromosomal copy number alterations that increase in frequency and complexity with increasing aggressiveness of the histological subtype. They show low somatic mutation loads and recurrent mutations have been identified in a very limited number of genes, most commonly GTF2I. High-throughput studies have identified significant genomic and epigenomic differences among the different histological subtypes of thymomas, paving the way for a better understanding of tumorigenesis and progression. This chapter provides a concise overview of molecular genetic alterations of potential clinical significance.