Chronic myelomonocytic leukemia (CMML) is a myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) chacaterized by persistent peripheral blood monocytosis, hypercellular bone marrow and dysplasia at least in one myeloid lineage. CMML shares much of its molecular landscape with other myeloid neoplasms, while differs from others such as chronic neutrophilic leukemia (CNL), given the high frequency of CSF3R mutations in the latter. In this article, we report a case of CSF3R-mutated CMML and dissect this rare entity by reviewing the medical literature, with the intent to understand how this rare mutation shapes CMML\'s clinical and morphological phenotype. CSF3R-mutated CMML emerges as a rare entity meeting the ICC/WHO diagnostic criteria for CMML and simultaneously showing clinical-pathological and molecular traits of CNL and atypical chronic myeloid leukemia, rising an important and difficult diagnostic and therapeutical issue.

BACKGROUND: Study of the molecular biological characteristics of chronic neutrophilic leukemia complicated with plasma cell disorder (CNL-PCD) and lymphocytic proliferative disease (CNL-LPD).
METHODS: The clinical data of a patient with chronic neutrophilic leukemia complicated with monoclonal gammopathy of undetermined significance (CNL-MGUS) in our hospital were reviewed, and the Chinese and/or English literature about CNL-PCD and CNL-LPD in PubMed and the Chinese database CNKI in the past 10 years was searched to analyze the molecular biological characteristics of this disease.
RESULTS: A 73-year-old male had persistent leukocytosis for 18 months. The white blood cell count was 46.77 × 109/L and primarily composed of mature neutrophils; hemoglobin: 77 g/L; platelet count: 189 × 109/L. Serum immunofixation electrophoresis showed IgG-λ monoclonal M protein. A CT scan showed splenomegaly. Next-generation sequencing (NGS) showed that CSF3R T618I, ASXL1 and RUNX1 mutations were positive. It was diagnosed as CNL-MGUS. We summarized 10 cases of CNL-PCD and 1 case of CNL-LPD who underwent genetic mutation detection reported in the literature. The CSF3R mutational frequency (7/11, 63.6%) was lower than that of isolated CNL. The ASXL1 mutations were all positive (3/3), which may represent a poor prognostic factor. The SETBP1 mutation may promote the progression of CNL-PCD. We also found JAK2, RUNX1, NRAS, etc. in CNL-PCD.
CONCLUSIONS: Chronic neutrophilic leukemia may be more inclined to coexist with plasma cell disorder. The CSF3R mutation in CNL-PCD is still the most common mutated gene compared with isolated CNL. Mutations in SETBP1 and ASXL1 may be poor prognostic factors for CNL-PCD.

Chronic neutrophilic leukemia (CNL) is a rare leukemia with approximately 150 total cases reported. Cutaneous neutrophilic infiltrates, including Sweet syndrome (SS) and leukemia cutis (LC), have been reported in six patients with CNL. In the setting of CNL, these two conditions are difficult to differentiate due to clinical and histopathological similarities, but it is important to do so because LC is associated with a worse prognosis. In general, SS is distinguished by its tenderness, fever, and improvement with steroids (vs chemotherapy for LC). Biopsy of LC reveals immature leukocytes, whereas SS shows almost exclusively mature leukocytes, but morphology alone may not be sufficient in some cases. Here, we report a case of a 72-year-old male with CNL and a cutaneous eruption with clinical and pathological features which made the distinction between the two diseases difficult.

BACKGROUND: Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative syndrome characterized by a significant increase in mature neutrophils. One of the most serious complications is the occurrence of bleeding events, which may sometimes lead to death.
METHODS: A 75-year-old patient presented with CNL, complicated by a severe bleeding phenotype. Biological investigations revealed platelet function defect and increase in neutrophil elastase. The follow-up was marked by an intracranial hemorrhage leading to the patient\'s death 7 months after diagnosis.
CONCLUSIONS: This bleeding phenotype has been reported several times in patients with CNL. However, the pathophysiological mechanisms that cause bleeding are not yet fully understood.

Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative neoplasm (MPN) with less than 40 cases of patients being reported or clinically suspected meeting with 2008 World Health Organization (\"WHO\") diagnostic criteria. The current diagnosis of CNL remains to exclude other diseases. Recently, a new biomarker of CSF3R mutations that is almost invariably present in CNL has been identified. There is no effective treatment for CNL, therefore prognosis of the disease is poor, but it may be attributed to the presence of both SETBP1 and CSF3R gene mutations. The presence or absence of CSF3R mutation did not affect survival, whereas a trend for shortened survival was observed among patients with SETBP1-mutation.
Here we report a 65-year old woman patient who presented with leukocytosis without sign of fever and tumors. Bone marrow aspirates showed a markedly hypercellular feature with 76%-92% myeloid and the dysplastic changes were found in about 7% of neutrophils cells. The bone marrow biopsy demonstrated marrow fibrosis with Gomori staining positive (+++~++++). Cytogenetic analysis showed 46,X,del (X) (q22). No molecular markers of BCR/ABL1 rearrangement (P210, P230, P190 and variably), JAK2V617F, FIP1L1-PDGFRA, TEL-PDGFRB, ZNF198-FGFR1 and SETBP1 mutations were identified, however, the CSF3R gene membrane proximal mutation (c.1853C > T/p.T618I sites) was detected by PCR techniques. The patient was diagnosed with CNL and died in about 2 months after disease diagnosis.
In clinical course, the CNL concurrently with severe bone marrow fibrosis and dysplastic features as well as X chromosomal abnormality may predict a worsening prognosis regardless of SETBP1 mutation status.

OBJECTIVE: To explored the diagnosis and treatment of chronic neutrophilic leukemia (CNL) complicated with multiple myeloma (MM).
METHODS: The clinical features and molecular biological characteristics of 2 patients with CNL complicated with MM were summarized, and the diagnosis and treatment of the patients were retrospectively reviewed.
RESULTS: The diagnosis of CNL complicated with MM was established in 2 cases. Case 1 had CSF3R mutation (P733T), but CSF3R-exon 14 mutation and SETBP1 mutation were all negative. The neutrophil count returned to normal when MM was successfully treated in case 1. When the patient relapsed, neutrophil count increased again.
CONCLUSIONS: Coexistence of CNL and MM is rare. CSF3R is a very important molecular marker for CNL. To the best of our knowledge, it\'s the first time to report the coexistence of CNL and MM carried CSF3R mutation (P733T). Chemotherapy regimens for MM may be effective in the treatment of CNL complicated with MM.

Chronic neutrophilic leukemia is an uncommon hematological entity. According to the WHO classification it is recognized as part of the family of myeloproliferative disorders. In the last 20 years seven patients have been diagnosed with chronic neutrophilic leukemia at our department. All but one had splenomegaly, two patients developed severe anaemia and in one case thrombocytosis was present at the time of diagnosis. White blood cell count ranged between 39 x 10(9)/1-71 x 10(9)/l with 80% of neutrophils and striking myeloid hyperplasia were present in the bone marrow without evidence of any dysplasia resembling chronic myelocytic leukemia. Granulocyte alkaline phosphatase scores were increased except one case and both cytogenetics (Philadelphia chromosome) and molecular biologic analysis (bcr/abl) revealed no alteration of any. Four patients have been followed up. Three of them died due to progression of chronic neutrophilic leukemia. One patient, initially receiving hydroxyurea + interferon therapy and showing progression, developed complete hematological remission with an eight week imatinib mesylate (Glivec) treatment. Beside of their own experiences the authors review the current literature and discuss differential diagnostic and therapeutic challenges, as well.

暂无摘要。

Chronic neutrophilic leukemia (CNL) is recognized as a distinct clinicopathologic entity characterized by sustained mature neutrophilic leukocytosis splenomegaly with bone marrow granulocytic hyperplasia without evidence of dysplasia or striking reticulin fibrosis. This diagnosis is contingent on thorough initial investigation and follow-up to exclude underlying causes of reactive neutrophilia, particularly if evidence of myeloid clonality is lacking. The optimal therapy for CNL remains uncertain. Current management decisions are based on anecdotal reports or extrapolated from therapeutic strategies effective in similar chronic clonal myeloid disorders. Because of the potential for blastic transformation and progressive refractory neutrophilia, allogeneic stem cell transplantation may be appropriate for younger patients. Continued reporting of all cases of CNL and responses to therapeutic strategies must be encouraged.

A male patient, aged 78, was found with chronic neutrophilic leukemia (CNL). The patient showed sustained mature neutrophilic leukocytosis, splenomegaly, a high leukocyte alkaline phosphatase score, elevated serum vitamin B12 and uric acid, myeloid hyperplasia and absence of ph\' chromosome in the bone marrow, with no evidence suggesting this condition to be a leukemoid reaction to an underlying disease. In addition to the above mentioned features, some functional characteristics of CNL cells were compared with normal cells. CNL is a very rare disease; some thought it as a variant of chronic myelogenous leukemia (CML). In this report a review of the literature is also included.