Ki-1 (CD30)-positive large cell lymphoma presented with leukemia: a case report.

A 77 year-old woman with Ki-1 positive large cell lymphoma who presented with leukemic phase of the disease is reported. She noticed general fatigue and fever in 1992 and was found to have anemia and abnormal lymphoid cells in the peripheral blood. The bone marrow was diffusely involved by these cells, differentials of which included acute megakaryocytic leukemia, malignant histiocytosis, and anaplastic large cell lymphoma. Immunophenotypic analysis showed that they were positive for CD3, HLA-DR, CD25 and CD30, but negative for CD4, CD8, CD19, FVIII and GpIIb/IIIa indicating Ki-1 positive lymphoma with T-cell lineage. It may involve bone marrow, but leukemic phase of the disease is rarely seen. Therefore, it should be added to the differential diagnosis when large anaplastic or pleomorphic cells are seen in the bone marrow and/or peripheral blood.