In UPN 3, UPN4, UPN6 and UPN13, the ASXL1 S689*, ASXL1 R693*, SF3B1 K700E and SETBP1 G870R mutations, studied using ultra-deep NGS, were undetectable at the time of primary cancer (NHL in UPN3 and UPN4, normal karyotype AML in UPN6 and B-ALL with a complex karyotype in UPN13) and were detected after 20, 113, 83 and 32 months from start of primary tumor treatment. The gene discussed is SF3B1; the disease is acute lymphoblastic leukemia.