[CD7 positive undifferenciated leukemia/lymphoma associated with leukemic pericarditis].

We report here a CD7 positive undifferenciated leukemia/lymphoma which showed a rapid clinical course. A 27-year-old female was complained of palpitation and edema. She had a mediastinal tumor and pericardial effusion. Lymphoblastic cells were found in the effusion, but in the peripheral blood initially. After admission the blast cells appeared in the peripheral blood, and they were revealed negative for peroxidase and had phenotype of CD7 and CD33 positive. The patient suffered from cardiac tamponade and died 15 days after admission. The Southern blotting of mediastinal tumor cells disclosed the germline configuration for TCR-beta a chain and the rearrangement of immunoglobulin heavy chain genes.