Chronic myelomonocytic leukemia in childhood

Abstract

A four-year-old child with recurrent infections and increasing hepatosplenomegaly over a three-year period was evaluated. Increased numbers of myeloid precursors packed the bone marrow and infiltrated the peripheral blood. A diagnosis of chronic myelogenous leukemia (CML) was considered but could not be confirmed by laboratory studies appropriate for the types of CML usually observed in childhood. Examination of the patient's peripheral blood smears revealed many atypical monocytoid cells with unipolar hairy projections. Scanning electron microscopy showed these to be leukemic monoblasts with characteristic broad-based ruffles on the cell surface. A population of myeloid precursors possessing narrow ridge-like profiles was also observed. Progressive infiltration of the spleen caused hypersplenism which necessitated splenectomy. Subsequently, massive liver and bone marrow involvement led to the patient's death. Terminally, the proliferating blast cells were demonstrated to be leukemic monoblasts by analysis of cytochemical staining patterns, surface immunoglobulins, serum lysozyme levels, and monocyte-mediated antibody-dependent cellular cytotoxicity studies. The findings in this case are most compatible with a diagnosis of chronic myelomonocytic leukemia (CMML), a condition not previously described in childhood. Several myeloproliferative disorders with prolonged survival have been reported in children, but special studies were not performed to determine which cell lines were abnormally proliferating. The similarities between these children and our patient with CMML suggest that monocyte studies may be useful in the diagnosis of these unusual disorders, provide insights into their pathogenesis, and aid in the selection of appropriate therapy.

Myelodysplasia and myeloproliferative disorders in childhood: an update

“…(2) Lower-dose chemotherapy has also been attempted using various agents such as low-dose cytarabine or mercaptopurine (Lilleyman et al, 1977;Thomas et al, 1981). Responses have been noted, but effect on outcome is uncertain and no long-term remissions off-therapy have been noted.…”

Prognostic factors and survival in chronic myelomonocytic leukaemia (CMML)

“…CMML may however be viewed as a spectrum of diseases with wide variations in peripheral blood leucocyte Morphology was examined on May-Grunwald-Giemsa counts and clinical course and someinvestigatorstained peripheral blood and bone marrow smears and the CMML shoud clin l considered as a distinct entity, with diagnosis of CMML made according to FAB criteria CMML should be (Bennett et al, 1982). Minimal diagnostic criteria for features of both myeloproliferative and myelodysplastic CMML were the presence of a total peripheral blood disorders (Solal-Celigny et al, 1984;Milner et al, 1977 Haznedar, 1985;Sans-Sabrafen et al, 1986; (Altman et al, 1974;Thomas et al, 1981 (cx-naphthyl acetate and chloroacetate) esterase staining, previously associated with MDS (Scott et al, 1983, were cytochemically assessed by conventional techniques Matenials and methods (Yam et al, 1971).…”

Chronic myelomonocytic leukaemia in infancy: A case report

“…The persistently normal levels of serum and urinary lysozyme remain unexplained although evidence that monocytic ele-ments predominated was provided by morphology, cytochemical staining, and response to VP-16, a drug with selective activity against myelomonocytic and monocytic leukaemias [5]. However, no case of chronic myelomonocytic leukaemia has been reported previously in infancy, although a single case in childhood has been described recently [ 6 ] , and in retrospect some of the 28 children with myelomonocytic leukaemia reviewed by Weisgerber et a1 [7] may have been examples of this disease.…”