NCIt definition : A rare childhood cancer predisposition syndrome caused by biallelic inheritance of
mutations in MLH1, MSH2, MSH6, or PMS2 genes. It is characterized by the development
of childhood cancers, usually hematological malignancies and/or brain tumors, and
colorectal cancers with multiple intestinal polyps. The majority of patients show
signs of neurofibromatosis type 1.;