PTPN11 and Noonan syndrome: Automatic referral criteria for cancer risk genetic counseling and consideration of genetic testing can also be made based on HHM histopathologies such as juvenile myelomonocytic leukemia (neurofibromatosis 1-NF1; Noonan syndrome—e.g., PTPN11, NRAS, and KRAS; Noonan-like syndrome—CBL) (16), low hypodiploid ALL (TP53) (17), or myelodysplastic syndrome (MDS) diagnosed in children or young adults (GATA2, SAMD9, SAMD9L, and SRP72) (5–8, 18, 19).