Translocation (10;12)(q24;q15) in a T-cell lymphoblastic lymphoma with myeloid hyperplasia.

We present a case of childhood T-cell lymphoblastic lymphoma (T-LBL) with a translocation (10;12)(q24;q15) as a main clonal abnormality, which to our knowledge is the first reported karyotype of this malignancy. The patient's peripheral blood and bone marrow showed marked leukocytosis mostly myeloid lineage cells, at diagnosis. The enlarged lymph node consisted of two different cell populations: CD2+/CD7+ prothymic lymphoblasts and a cluster of peroxidase-positive myeloid cells around vessels. This case might represent a rare but distinct clinical entity of LBL.