[1585] Myeloid Neoplasms with inv(3)(q21q26.2)/t(3;3)(q21;q26.2) Are Aggressive Neoplasms Irrespective of Blast Count

Douglas W Warden, Heesun J Rogers, James Cook, Eric D Hsi. Cleveland Clinic, Cleveland, OH

Background: Acute myeloid leukemia (AML) with inv(3)/t(3;3) is a unique subset of AML with recurrent cytogenetic abnormalities (RCA) that portends a dismal prognosis. Although myelodysplastic syndrome (MDS) with inv(3)/t(3;3) are also reported to have poor prognosis, the WHO classification does not yet advocate considering such cases as AML with RCA.
Design: We reviewed all myeloid neoplasms with inv(3)(q21q26) or t(3;3)(q21;q26) by conventional cytogenetics from our institution. Clinical data and bone marrow biopsies were reviewed for outcome-data and for morphologic analysis. Kaplan-Meier survival analysis with log rank testing was used to evaluate overall survival (OS).
Results: We identified 21 patients who met our criteria, including 8 patients with MDS and 13 patients with AML (see table).

Characteristics of patients with myeloid neoplasms and inv(3)/t(3;3)
Clinicopathologic CharacteristicsMDS with inv(3)AML with inv(3)
Number (n=)813
Age (median, range)70.3 (45-85)57.1 (17-77)
Survival (median, months)7.14.9
Blast% (mean, range)3 (range 0-9)38.3 (9-92)
Progress to AML (n=)2N/A
1-2 lineages37

Review of pathologic features demonstrated small, dysplastic megakaryocytes as a common feature of patients with inv(3)/t(3;3). There was no significant difference between MDS and AML patients with respect to white blood cell count, hemoglobin, or platelet count. OS for patients with MDS was similar to patients with AML (median OS=7.1 vs 4.9 months; p=0.26, log-rank test) despite significant differences in mean blast counts (3.0 vs 38.3, p=0.0003). Patients with additional cytogenetic abnormalities (n=11) had significantly shorter OS than those with isolated inv(3)/t(3;3) (n=10; median OS =3.4 vs 12.4 months, p=0.006, log-rank test). The most common additional abnormality was monosomy 7 (n=7), which portended an even shorter OS of 3.0 months. Overall, 25% (2/8) of MDS patients with inv(3)/t(3;3) progressed to AML.
Conclusions: Patients with myeloid neoplasms (AML or MDS) and inv(3)/t(3;3) abnormalities follow a similarly aggressive clinical course. Additional chromosomal abnormalities, most typically monosomy 7, provide added negative impact on OS. These data support considering myeloid neoplasms with inv(3)/t(3;3) as an AML with RCA, regardless of the blast percentage.
Category: Hematopathology

Tuesday, March 20, 2012 9:30 AM

Poster Session III # 213, Tuesday Morning


Close Window