만성 호산구 백혈병. Chronic eosinophilic leukemia, NOS (CEL)

다양한 혈액종양질환을 정리하고 있습니다.

 

오늘은 골수증식성 종양 (Myeloproiferative neoplasm, MPN) 중 

만성 호산구 백혈병 (Chronic eosinophilic leukemia, NOS)에 대해 알아보겠습니다.

 

귀여운 라이언이 만성 호산구 백혈병, Chronic eosinophilia leukemia를 가리키고 있어요!

 

1. Definition

Chronic eosinophilic leukemia (CEL) not otherwise specified (NOS), is a MPN in which an autonomous, clonal proliferation of eosinophil precursors results in persistently increased numbers of eosinophils in the PB, BM, and peripheral tisssues.

Organ damage occurs as a result of leukemic infiltration or of the release of cytokines, enzymes, or other proteins by the eosinophils.

CEL NOS는 다른 MPN (CML, CNL, PV, ET, PMF)과 MDS/MPN (atypical CML, CMML)를 배제한 뒤 진단 가능합니다.

따라서, CEL NOS를 진단하기 위해서는 BCR-ABL1 fusion, PDGFRA, PDGFRB, FGFR1, PCM1-JAK2 gene rearrangement, ETV-JAK2, BCR-JAK2 fusion 등을 배제해야 합니다. 

진단 기준은 다음과 같습니다.

2. Localization

CEL NOS is a multisystemic disorder.

The PB and BM are always involved.

Tissue infiltration by eosinophils and the release of cytokines and humoral factors from eosinophil granules lead to tissue damage in multiple organs; heart, lung, CNS, skin, GI tract etc

 

3. Clinical features

- Constitutional Sx : weight loss, night sweats, fever, fatigue, cough, angio-edema, muscle pain, pruritus, diarrhea

- Endomyocardial fibrosis

- Peripheral neuropathy

- CNS dysfunction

- Pulmonary Sx d/t lung infiltration

 

4. Microscopy

Peripheral Blood

- Eosinophilia, mainly of mature eosinophils

Bone marrow

- Hypercellular d/t eosinophilic infiltration

CEL NOS vs. IHES

Reactive eosinophilia in ALL

 

5. Differential diagnosis

Diagnosis requires positive evidence of the leukemic nature of the condition and exclusion of myeloid neoplasms with rearrangement of PDGFRA, PDGFRB, FGFR1 or fusion of PCM1-JAK2, ETV6-JAK2, BCR-JAK2.

 

The diasgnostic process often starts with exclusion of reactive eosniophilia.

- Parasitic infection

- Allergy

- Pulmonary diseases such as Loffler syndrome

- Collagen vascular disorders

- Kimura disease

 

In addition, a number of neoplastic disorders can induce secondary eosinophilia, which needs to be excluded.

- T-cell lymphoma : Lymphocytic variant of hypereosinophilic syndrome

- Hodgkin lymphoma

- Systemic mastocytosis

- Lymphoblastic leukemia

- CMML with eosinophilia

- Atypical CML, BCR-ABL1 negative, with eosinophilia

 

Finally, Idiopathic HES should be excluded.

 

Ref)

The WHO Classification of Tumours of Haematopoietic and LymphoidTissues, IARC 2017