만성 호중구 백혈병. Chronic neutrophilic leukemia (CNL)

다양한 혈액종양질환을 정리하고 있습니다.

 

오늘은 골수증식성 종양 (Myeloproiferative neoplasm, MPN) 중 

만성 호중구 백혈병 (Chronic neutrophilic leukemia, CNL)에 대해 알아보겠습니다.

 

라이언 이모티콘이 CNL을 가르키고 있어요!

 

1. Definition

Chronic neutrophilic leukemia is a rare MPN characterized by sustained PB neutrophilia, BM hypercellularity due to neutrophilic granulocyte proliferation, and hepatosplenomegaly.

The diagnosis requires exclusion of reactive neutrophilia and other MPN, MDS/MPN.

 

2. Epidemiology

The true incidence of CNL is unknown.

전세계적으로 150 케이스 정도밖에 보고된 바 없다. 매우 드문 질환이다.

 

3. Clinical features

- Splenomegaly

- Hepatomegaly

- Bruising, purpura

- Bleeding from mucocutaneous surfaces, GI tract

- Gout, pruritus

 

4. Microscopy

Peripheral Blood

- The peripheral blood shows neutrophilia, with a WBC count ≥ 25,000/uL.

- Neutrophil precursors (promyelocytes, myelocytes, and metamyelocytes) account for < 10% of  the WBCs.

- Myeloblast is never observed in the PB.

- Toxic granulation and Dohle bodies appear to be more consistently present in plasma cell-associated leukemoid reactions than in CNL.

Bone Marrow

- The BM biopsy shows hypercellularity, with neutrophilic proliferation.

- M:E ratio may reach ≥ 20:1

- Erythroid and megakaryocytic proliferation may also occur.

- Significant dysplasia is not present in any of the lineages.

Given the frequency of neutrophilic leukemoid reaction in association with MM and MGUS, the bone marrow should be examined for evidence of a plama cell neoplasm.

If plasma cell abnormalities are present, clonality of the neutrophil lineage should be demonstrated by cytogenetic or molecular techniques before a Dx. of CNL is made.

 

6. Genetic profile

Cytogenetic studies are normal in nearly 90% of cases. In the remaining cases, reported clonal karyotypic abnormalities include gains of chr 8,9,21; del(7q); del(20q); del(11q); del(12p); nullisomy 17; a complex karyotype; and several non-recurrent translocations.

The distinction of CNL from the neutrophilic variant of CML, BCR/ABL1(+) should rely on molecular analysis.

CNL is now known to be strongly associated with CSF3R mutation, often together with mutation of SETBP1 or ASXL1.

특히, CSF3R 및 ASXL1 mutation이 동반된 경우, 예후가 나쁘다고 알려져 있습니다.

 

 

Ref)

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