Additional chromosomal abnormality of inv(16)(p13q22) to del(7)(q32) in a patient with acute myelomonocytic leukemia

: We report a 54-year-old man with acute myeloid leukemia (AML) carrying del(7)(q32) and inv(16)(p13q22). He was diagnosed as having AML M4Eo according to the FAB classification. RT-PCR for CBFβ/MYH11 gene was positive. Karyotype analysis revealed the primary chromosomal abnormality to be del(7)(q32) and inv(16)(p13q22) developed as a secondary abnormality. He achieved complete remission after one course of induction chemotherapy and remained in remission after several courses of consolidation therapy. del(7q) is classified into an intermediate risk group or an adverse risk group, while inv(16)/t(16;16) is classified into a favorable risk group. Some AML cases with inv(16)/t(16;16) exhibit del(7q) as an additional chromosomal abnormality. It was reported that such cases showed good prognosis despite the presence of del(7q). However, AML cases with del(7q) and inv(16)/t(16;16) as secondary chromosomal abnormalities are rare. Further study is needed to clarify the clinical manifestations of such cases.