SEER is an authoritative source of information on cancer incidence and survival in the United States. SEER currently collects and publishes cancer incidence and survival data from population-based cancer registries covering approximately 28 percent of the U.S. population.
9 - Grade/differentiation unknown, not stated, or not applicable
Chronic eosinophilic leukemia
Chronic eosinophilic leukemia (and the hypereosinophilic syndrome)
Hypereosinophilic (idiopathic) syndrome
Persistent high eosinophil count when all known causes of a raised eosiniphil count (such as parasite infection) have been excluded. Rare variant of acute myeloid leukemia in which blasts and immature eosinphils proliferate. CNS involvement appears to be common.
Autonomous clonal proliferation of eosinophilic precursors results in persistently increased numbers of eosinophils in the blood, bone marrow, and peripheral tissues.
Diagnosis of exclusion when secondary and clonal causes of eosinophilia are excluded. HES is proven by persistent eosinophilia that is associated with damage to multiple organs. CEL is a multisystem disorder. The peripheral blood and bone marrow are always involved. Tissue infiltration by the eosinophils and release of cytokines and tumoral factors from the eosinophil granules lead to tissue damage in a number of organs, but the heart, lungs, CNS, skin and GI tract are commonly involved. The patient must have a sustained absolute eosinophil count greater than 500/pl that persists longer than six months. The physician excludes reactive eosinophilia, eosinophilia secondary to other neoplastic diseases including T-cell neoplasia and other myeloid disorders. If above excludes peripheral blood blasts >2%, bone marrow >5% but <19%. HES is traditionally treated with prednisone. Second-line drugs are interferon or hydroxyurea which induce remission in the majority of patients. If the prednisone. interferon and hydroxurea are not effective, the patient may receive various chemotherapeutic drugs.