NF1 and chronic myelogenous leukemia, BCR-ABL1 positive: Reported malignancies in the “classic” NF1 group included MPNSTs (n = 15), chronic myeloid leukemia (n = 1), rhabdomyosarcoma (n = 1), and breast cancers (n = 2), with some patients developing several malignant or non-malignant tumors.