Evidence for a lymphotropic nature of circulating plasmacytoid monocytes: findings from a case of CD56+ chronic myelomonocytic leukemia.

Because the cells previously designated plasmacytoid T cells share major immunophenotypic features with cells of the mononuclear-phagocyte system, they have been re-named and are now known as plasmacytoid monocytes (PM). We describe a unique case of chronic myelomonocytic leukemia with circulating PM. The patient, a 48-year-old man, presented initially with refractory anemia. Four years later his general condition deteriorated, accompanied by an increase in leukocytes to 200,000/microliters blood. The bone marrow histology was interpreted as compatible with a diagnosis of chronic myelomonocytic leukemia. Two months before he died, the patient developed generalized lymphadenopathy clinically simulating malignant lymphoma. Histologic examination of an axillary lymph node revealed diffuse infiltration by PM. The PM in the lymph node and some circulating cells closely resembling PM expressed L-selectin, a finding that could be interpreted as a morphologic correlate of their marked lymphotropism. The detection of large numbers of CD56/CD33 double-positive circulating blast cells by FACS analysis strongly supported the diagnosis of a leukemia of myelogenous origin. The patient died of tumor cachexia. Autopsy revealed widespread leukemic infiltrates (always containing clusters of PM) in bone marrow, spleen, liver, lymph nodes, and mucosa-associated lymphoid tissue of the oropharynx. The final diagnosis was one of chronic myelomonocytic leukemia with marked lymphotropism and partial differentiation towards PM. We consider that the rare instances of a hematologic tumor with differentiation towards PM should be classified amongst the myelogenous leukemias.

[Transplantation of bone marrow from unrelated donors in chronic myeloid leukemia]. / Transplantation von Knochenmark unverwandter Spender bei chronischer myeloischer Leukämie.

Bone marrow transplantations in four patients (aged 8-28 years, median 27 years) with chronic myeloid leukaemia (CML) were performed from unrelated donors who were HLA-identical and MLC-negative. One patient was in the stage of refractory blast crisis, one in a chronic phase, and two in the second chronic phase. Conditioning treatment consisted of fractionated radiation and administration of cyclophosphamide; in the patients with their second chronic phase additionally etoposide. Cyclosporin A and methotrexate were administered to prevent graft versus host reaction. The patient in the blast crisis died on day 12 after transplantation of Candida pneumonia. The other three patients are still alive 128, 306 and 530 days, respectively, after transplantation, only a mild form of graft versus host disease having occurred. It is suggested that for patients younger then 50 years with CML in the chronic phase an unrelated donor should be searched for in the absence of a familial donor.