CHRONIC NEUTROPHILIC LEUKEMIA EVOLVING FROM A MYELODYSPLASTIC SYNDROME

Chronic neutrophilic leukemia (CNL) is a rare hematologic disorder usu ally presenting with a persistent neutrophilia in the leukemoid range (WBC > 40-50 x 10(9)/l) and consisting largely of mature neutrophils. Patients have no obvious cause for an elevated white count and typical ly have an elevated leukocyte alkaline phosphatase score, hepatospleno megaly, elevated vitamin Bit and are Philadelphia chromosome-negative. CNL has occasionally been associated with paraproteinemia or outright myeloma. Dysplastic features within the neutrophils in CNL have rarel y been reported. We report the clinical, pathological and cytogenetic features of a case of CNL in an elderly white female initially diagose d with refractory anemia with excess blasts, which subsequently progre ssed to CNL.