Agranular CD4(+)CD56(+) blastic natural killer leukemia/lymphoma

Elastic natural killer cell leukemia/lymphoma (blastic NKL/L) is characteri zed by blastic morphology and a distinctive immunophenotype combining blast ic features and cytologically resembling acute myeloid or lymphoid leukemia . The clinical, pathologic, and cytogenetic features of blastic NKL/L have not yet been systematically identified. We report herein a case of blastic NKL/L with skin lesion, adenopathy, and systemic lymphoadenopathy. The iden tified tumor cells were positive for CD4 and CD56, and negative for T-cell, B-cell, and myeloid markers. T-cell receptor beta, gamma, delta, and immun oglobulin heavy chain genes in the bone marrow cells showed germ-line confi gurations. Southern blot analysis with a terminal probe did not reveal any Epstein-Barr virus infection. Although patients diagnosed as blastic NKL/L have generally shown chemotherapy resistance and poor prognosis, our patien t was treated with a combined chemotherapy, which is also used for acute ly mphoblastic leukemia, and has maintained complete remission (CR) for more t han 13 months. In addition to clinical investigations, we thoroughly analyz ed his karyotype by using a combination of G-banding and a new technique, s pectral karyotyping. The karyotype was described as 45, XY, der(l)t(1;20)(p 32;q11.2), der(6) (1pter --> 1p32:: 6p21.1 --> 6q13:: 7q11.2 --> 7qter), de r(7) t(7;20)(q11.2;q11.2). t(13;14)(q14;q32), der(13)t(6;13) (p21.1;q14), - 20.