Cancer Risk and Spectrum in Individuals with RASopathies

The RAS/mitogen-activated protein kinase (MAPK) pathway is a highly conserved ubiquitous cellular signaling system that regulates critical cellular functions including proliferation, differentiation, survival, and apoptosis. Thus, dysregulation of this pathway has profound organismal consequences. Germline, mosaic, and somatic mutations in genes encoding proteins of the RAS/MAPK signaling pathway result in a variety of disorders. We review the current state of knowledge of syndromes caused by germline or mosaic aberrations in components of the RAS/MAPK pathway focusing on the cancer risk and spectrum associated with these conditions. We also review practical recommendations to address the elevated cancer risk.