JUVENILE CHRONIC MYELOGENOUS LEUKEMIA

Juvenile chronic myelogenous leukemia (JCML) is an aggressive myelopro liferative disorder of childhood that differs both clinically and path ologically from adult type, Philadelphia chromosome positive chronic m yelogenous leukemia, and from the other myeloproliferative disorders t hat are more common in adulthood. The disease can have widely varying clinical presentations and shares many features with the monosomy 7 sy ndrome and chronic myelomonocytic leukemia. With no specific marker ch romosome, establishing the diagnosis can be difficult, and relies on a constellation of clinical, pathologic, and laboratory findings. This article discusses the differential diagnosis of JCML with an emphasis on the pathologic findings and laboratory data that are particularly i mportant for confirming the diagnosis. The sensitivity, specificity, a nd clinical utility of cell culture colony assays are reviewed. Finall y, current knowledge of the biology of JCML and some of the controvers ies regarding this disease are discussed.