Trisomy 11 as an isolated abnormality in acute myeloid leukemia is associated with unfavorable prognosis but not with an NPM1 or KIT mutation.

Trisomy 11 (+11) as an isolated abnormality is a rare event in patients with acute myeloid leukemia (AML) and is associated with poor prognosis. We describe the clinicopathologic features of 18 AML patients with isolated +11 and their mutation status of NPM1, FLT3, NRAS ,KRAS, and KIT. Fourteen patients had de novo AML and 4 patients had a history of myelodysplastic syndrome (MDS). Fifteen patients had a progressive clinical course with refractory or relapsed disease. The median overall survival was 5 months (range, 2 to 48 months). Only 1 patient achieved complete remission after undergoing stem cell transplantation. The bone marrow median blast count was 65% (range, 22 to 86) and 14 patients had blasts >50%. The most common type of AML was AML without maturation (7 patients) classified by the World Health Organization classification system, or M1 (10 patients) by the French-American-British (FAB) system. FLT3 mutations were detected in 3 of 15 (20%) cases tested. RAS mutation was present in 1 of 16 (6%) cases and there was no evidence of NPM1 of KIT mutations (each tested in 12 cases). Our findings confirm previous reports that isolated +11 is associated with a poor prognosis in patients with AML and tends to be associated with FAB-M1 morphologic features. No evidence of NPM1 or KIT mutations were identified.