摘要目的:探讨伴罕见 KIT D816H突变系统性肥大细胞增生症合并相关血液肿瘤(SM-AHN)患者的临床、实验室检查特点及诊疗策略，并进行相关文献复习。 方法:选择2020年7月20日、2021年7月8日，海军军医大学第一附属医院(上海长海医院)收治的2例伴 KIT D816H突变SM-AHN患者为研究对象(患者1、2)。2例患者均为女性，年龄分别为60、59岁。对2例患者采取伊马替尼维持治疗与CLAG(克拉屈滨＋阿糖胞苷＋粒细胞集落刺激因子)联合达沙替尼方案治疗。采用回顾性研究方法，对患者病史、临床特征、实验室检查结果及治疗过程进行分析。本研究患者1、2分别随访截至2024年8月8日和2021年9月21日。本研究以"系统性肥大细胞增生症""系统性肥大细胞增生症合并相关血液肿瘤""肥大细胞白血病"" KIT D816H""systemic mastocytosis""systemic mastocytosis with an associated hematological neoplasm""SM""SM-AHN""mast cell leukemia"及"MCL"为中、英文关键词，在中国知网数据库、维普数据知识服务平台、万方数据知识服务平台和PubMed数据库中，检索伴 KIT D816H突变SM/肥大细胞白血病合并相关血液肿瘤(SM/MCL-AHN)相关文献，总结与本研究伴 KIT D816H突变SM-AHN患者相关文献报道患者的诊疗资料。检索时间为2000年1月1日至2024年8月8日。本研究符合2013年修订的《世界医学协会赫尔辛基宣言》要求，并取得受试者及其家属知情同意。 结果:①病史采集。患者1因异基因造血干细胞移植(allo-HSCT)后6年"反复咳嗽、气促"入院。病史采集：患者1因体检发现白细胞计数(WBC)减少及血红蛋白(Hb)值偏低于外院就诊。根据骨髓细胞形态学和免疫分型检查结果诊断为骨髓增殖异常性肿瘤伴原始细胞增多Ⅰ型(MDS-RAEB-Ⅰ)。遂接受维甲酸、沙利度胺及地西他滨治疗。治疗后，骨髓原始细胞比例仍为7%。2014年9月14日患者1于本院血液病科行人类白细胞抗原(HLA)全相合同胞供者allo-HSCT。移植后患者1的骨髓细胞形态学、嵌合率、微小残留病(MRD)均在正常范围，随访未见明显异常。患者2因"双侧牙龈肿痛5 ＋个月，伴胸闷、乏力4 ＋个月"入院。病史采集：患者2既往体健。患者2因血常规检查结果示原始细胞，转入血液病科治疗。②相关实验室检查结果。入院后，患者1血常规检查结果示，WBC、Hb值、血小板计数分别为2.45×10 9/L、73 g/L、193×10 9/L。骨髓细胞形态学检查结果示，骨髓有核细胞增生明显活跃，异常细胞比例为87%，氯乙酸AS-D萘酚酯酶染色结果呈强阳性，甲苯胺蓝染色结果呈阳性，含嗜碱性颗粒细胞(嗜碱性粒细胞或者肥大细胞)异常增生骨髓象。骨髓细胞免疫分型检查结果示，异常细胞比例为47%，该群细胞表达CD13、CD33、CD117，弱表达CD64、CD11c、CD4。染色体核型分析结果示，46，XX[3]；分子遗传学检查结果示，嵌合率为52.60%。二代测序(NGS)结果示， KIT D816H、 DNMT3A W601X、 IDH2 R140Q突变率分别为35.51%、28.03%和27.55%。骨髓病理学检查结果示，有核细胞、异常细胞高度增生，网状纤维增生，骨髓纤维化(MF)Ⅱ级。骨髓免疫组织化学结果示，髓过氧化物酶(MPO)(－)、CD20(－)、CD38(偶见＋)、Lyso(－)、CD34(－)、CD2(－)、CD38(偶见＋)、CD117(＋)、CD3(－)、骨形态发生蛋白(BM)2(＋)、CD235(红系＋)、CD5(－)、Ki-67(偶见＋)、CD42b(－)、CD7(－)、CD68(＋)，提示髓细胞白血病。入院后患者2血常规检查结果示，WBC、Hb值、血小板计数分别为10.62×10 9/L、62 g/L、14×10 9/L，原始细胞比例为33%。骨髓细胞形态学检查结果示，原始细胞比例为57%，原始细胞过氧化物酶(POX)染色结果呈强阳性，氯乙酸AS-D萘酚酯酶染色结果呈阳性，提示急性髓细胞白血病(AML)(M2b)骨髓象。骨髓细胞免疫分型检查结果示，异常细胞比例为39%，该群细胞表达CD19、CD34、CD117、HLA-DR、CD123、CD38，弱表达CD13、CD33、MPO，部分表达CD56 。染色体核型分析结果示，46，XX，t(8；21)(q22；q22)[18]/46，XX，idem，i(17)(q10)[1]/46，XX[1]；荧光原位杂交(FISH)检查结果示， RUNX1∷ RUNX1T1融合基因呈阳性；分子遗传学检查结果示， RUNX1∷ RUNX1T1融合基因表达量为286.79%，肾母细胞瘤蛋白( WT)表达量为24.49%。诱导治疗结束后，患者2骨髓细胞形态学检查结果示，原始细胞比例为4%，肥大细胞比例为17%。MRD的流式细胞术(FCM)检查结果示，异常细胞占有核细胞的5%，该群细胞表达CD34、CD117、CD56，弱表达CD64、CD15，另可见CD117 ＋＋细胞比例约为18%。染色体核型分析结果示，45，X，－X，t(8；21)(q22；q22)，i(17)(q10)[1]；FISH检查结果示， RUNX1∷ RUNX1T1融合基因呈阳性；分子遗传学检查结果示， RUNX1∷ RUNX1T1融合基因表达量为105.41%， WT1表达量为60.96%；NGS结果示， KIT D816H突变率为39.31%， KRAS G12D突变率为4.64%。对原始细胞与肥大细胞进行NGS分析结果示，原始细胞 KIT D816H突变率为8.10%，肥大细胞 KIT D816H突变率为45.34%。③诊治过程。患者1被诊断为伴 KIT D816H突变SM-AHN。对患者1予伊马替尼400 mg/d维持治疗，疗效为疾病稳定(SD)，患者随访期内带病生存，未发生骨髓增殖异常性肿瘤(MDS)复发，SM亦未好转。患者2被诊断为伴 RUNX1∷ RUNX1T1融合基因AML，行阿糖胞苷＋伊达比星方案诱导化疗。诱导治疗后，患者2复查骨髓细胞形态学检查结果示达部分缓解(PR)，并且根据复查结果被诊断为伴 KIT D816H突变SM-AHN。对患者2采取CLAG(克拉屈滨＋阿糖胞苷＋粒细胞集落刺激因子)联合达沙替尼方案化疗。由于感染粪肠球菌，出现败血症，患者2因以呼吸衰竭为主的多器官衰竭死亡，仅生存2个月。④文献复习。按照本研究设定的文献检索策略，共筛选出3篇报道伴 KIT D816H突变SM/MCL-AHN患者的文献，均为英文文献，共报道5例患者(患者3～7)，加上本研究患者1、2，共7例患者。7例患者合并血液肿瘤包括MDS(1例)，AML(2例)，B细胞非霍奇金淋巴瘤(B-NHL)(1例)，慢性嗜酸粒细胞白血病(CEL)(2例)，慢性粒-单细胞白血病(CMML)(1例)。7例患者中，6例接受的治疗包括化疗、靶向治疗和allo-HSCT，1例患者未接受治疗。7例患者中3例allo-HSCT后死于复发及移植并发症，1例接受靶向治疗后带病生存，1例接受化疗后死亡，1例未报道结局，1例未治疗存活。 结论:伴 KIT D816H突变SM-AHN属罕见血液系统疾病，骨髓细胞形态学、免疫学、细胞遗传学与分子遗传学检查结果的综合分析是其诊断的关键。该疾病治疗与合并相关血液肿瘤类型相关，目前尚无标准治疗方案，化疗、allo-HSCT联合靶向治疗可作为潜在的治疗选择。

abstractsObjective:To investigate clinical features, laboratory examination characteristics, diagnosis and treatment of systemic mastocytosis with an associated hematological neoplasm (SM-AHN) with rare KIT D816H mutation and review relevant literature. Methods:On July 20, 2020 and July 8, 2021, two cases of SM-AHN patients with KIT D816H mutation admitted to the First Affiliated Hospital of Naval Medical University (Shanghai Changhai Hospital) were selected as study subjects (patient 1, 2). Both patients are female, aged 60 and 59 years old, respectively. Two patients were treated with imatinib maintenance therapy and CLAG (cladribine+ cytarabine+ granulocyte colony-stimulating factor) combined with dasatinib regimen. Patients′ medical history, clinical characteristics, laboratory test results, and treatment process were analysed retrospectively. In this study, patient 1, 2 were followed up until August 8, 2024, and September 21, 2021. China National Knowledge Infrastructure database, VIP data knowledge service platform, Wanfang knowledge service platform and PubMed database were searched for relevant literature using " systemic mastocytosis" " systemic mastocytosis with an associated haematological neoplasm" " KIT D816H" " SM" " SM-AHN" " mast cell leukemia" and " MCL" as keywords in Chinese and English. Summarize the diagnosis and treatment of related cases of SM/mast cell leukemia with an associated hematological neoplasm (SM/MCL-AHN). Search retrieval was from January 1, 2000 to August 8, 2024. The procedures followed in this study were in line with the requirements of the Helsinki Declaration of the World Medical Association revised in 2013, and informed consent was obtained from the subject for clinical study. Results:① Medical history. Patient 1 was admitted due to " recurrent coughing and shortness of breath" 6 years after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Medical history: patient 1 sought medical attention due to a decrease in white blood cell count (WBC) and low haemoglobin (Hb) value discovered during a physical examination. Patient 1 was diagnosed as myelodysplastic neoplasms-refractory anemia with excess blasts type I (MDS-RAEB-Ⅰ) based on bone marrow cell morphology and immunophenotyping examination results. Hence, patient 1 accepted treatment with retinoic acid, thalidomide and decitabine in other hospital. After treatment, there were still 7% blasts in the bone marrow. On September 14, 2014, human leukocyte antigen (HLA) identical sibling donor allo-HSCT was performed in Hematology Department of our hospital on September 14, 2014. Morphology, chimerism rate, and minimal residual disease (MRD) after allo-HSCT were within normal range, and no significant abnormalities were observed during follow-up. Patient 2 was admitted on July 7, 2021 due to " bilateral gum swelling and pain for 5 + months, accompanied by chest tightness and fatigue for 4 + months". Medical history: patient 2 was previously in good health. Patient 2 was transferred to Hematology Department for treatment due to blasts in blood routine examination results. ② Relevant laboratory examination results. After admission, Patient 1′s blood routine examination results showed WBC value of 2.45×10 9/L, Hb value of 73 g/L, and platelet count of 193×10 9/L. Morphological examination results of bone marrow cells showed that proliferation of nucleated cells was significantly active, with an abnormal cell proportion of 87%. Results of naphthol AS-D chloroacetate esterase stain was strongly positive, and toluidine blue stain was positive. Bone marrow image contained abnormal proliferation of basophil or adipocytes. Immune phenotype of bone marrow cells showed that proportion of abnormal cell populations was 47%, and these cells expressed CD13, CD33, CD117, with weak expression of CD64, CD11c, CD4. Chromosome analysis marked with 46, XX[3]. Result of donor chimerism rate was 52.60%. Results of next generation sequencing (NGS) showed that the mutation rate of KIT D816H, DNMT3A W601X, IDH2 R140Q were 35.51%, 28.03% and 27.55%, respectively. Bone marrow pathology and immunohistochemistry indicated excessive proliferation of nucleated cells and abnormal cells, reticular fibrosis, and grade Ⅱ bone marrow fibrosis (MF). Immunohistochemical results showed, myeloperoxidase (MPO) (-), CD20 (-), CD38 (occasionally+ ), Lyso (-), CD34 (-), CD2 (-), CD38 (occasionally+ ), CD117(+ ), CD3(-), bone morphogenetic protein (BM) 2 (+ ), CD235 (erythroid+ ), CD5 (-), Ki-67 (occasionally+ ), CD42b(-), CD7(-), CD68(+ ), suggesting myeloid leukemia. After admission, blood routine examination results of patient 2 showed that WBC, Hb value, platelet count were 10.62×10 9/L, 62 g/L and 14×10 9/L, respectively. And proportion of blasts was 33%. Bone marrow morphology and cytochemistry staining showed that proportion of blasts was 57%, and blasts peroxidase (POX) stain was strongly positive, and naphthol AS-D chloroacetate esterase stain was positive, indicating acute myeloid leukemia (AML)(M2b). Immune phenotype of bone marrow cells showed that the proportion of abnormal cells was 39%, and expressed CD19, CD34, CD117, HLA-DR, CD123, CD38, with weak expression of CD13, CD33, MPO, partial expression of CD56. Chromosome analysis marked with 46, XX, t(8; 21)(q22; q22)[18]/46, XX, idem, i(17)(q10)[1]/46, XX[1]. Fluorescence in situ hybridization (FISH) result showed that RUNX1∷ RUNX1T1 fusion gene was positive. Molecular genetic results showed that expression level of RUNX1∷ RUNX1T1 fusion gene was 286.79%, and expression level of Wilms tumor( WT1) was 24.49%. After induction therapy, patient 2 showed that blasts were 4% and mast cells were 17%. MRD result by flow cytometry(FCM) showed that blasts accounted for 5%, and expressed CD34, CD117, CD56, with weak expression of CD64, CD15. Meanwhile, about 18% CD117 strongly positive cells can be seen. Chromosome analysis marked with 45, X, -X, t(8; 21)(q22; q22), i(17)(q10)[1]. FISH result showed RUNX1∷ RUNX1T1 fusion gene was positive. Molecular genetics indicated RUNX1∷ RUNX1T1 fusion gene expression level of 105.41%, WT1 expression level of 60.96%; NGS result showed KIT D816H mutation rate of 39.31%, and KRAS G12D mutation rate of 4.64%. Results of NGS analysis on blasts and mast cells displayed that KIT D816H mutation rate in blasts was 8.10%, while mutation rate was 45.34% in mast cells. ③ Diagnosis and treatment process. Patient 1 was diagnosed SM-AHN with KIT D816H mutation and received maintenance treatment with imatinib 400 mg/d. Efficacy was stable disease (SD), and patient 1 has survived with the disease during the follow-up without any signs of myelodysplastic neoplasms (MDS) recurrence nor improvement in SM. Patient 2 was diagnosed as AML with RUNX1∷ RUNX1T1 fusion gene, and received induction chemotherapy with cytarabine+ idarubicin regimen. After induction therapy, bone marrow cell morphology showed partial remission(PR). Patient 2 was diagnosed as SM-AHN with KIT D816H mutation according to reexamination results, and received CLAG (clavubine+ cytarabine+ granulocyte colony stimulating factor) combined with dasatinib regimen. Due to infection with Enterococcus faecalis, sepsis occurred and patient 2 died from multiple organ failure, mainly respiratory failure, with a survival of only 2 months. ④ Literature review. According to the literature search strategy set in this study, a total of 3 articles reporting on SM/MCL-AHN patients with KIT D816H mutation were screened, all of which were English literature, and 5 patients (patients 3-7) were reported. There were 7 patients including patient 1, 2 in this study. Associated hematological neoplasms of 7 patients included MDS (1 case), AML (2 cases), B-cell non-Hodgkin lymphoma (B-NHL) (1 case), chronic eosinophilic leukemia (CEL) (2 cases), chronic myelomonocytic leukemia (CMML) (1 case). Seven patients received treatment including chemotherapy, targeted therapy, and allo-HSCT, and one patient received no treatment. Among 7 patients, 3 died after allo-HSCT due to recurrence and transplantation complications, 1 survived after receiving targeted therapy, 1 died after receiving chemotherapy, 1 had no reported outcome, and 1 survived without treatment. Conclusions:SM-AHN with KIT D816H mutation is a rare disease, and comprehensive analysis of bone marrow cell morphology, immunology, cytogenetics, and molecular genetics is crucial for its diagnosis. Treatment of this disease is mainly related to type of associated hematological neoplasm, and there is currently no standard therapeutic schedule. Chemotherapy, allo-HSCT combined with targeted therapies may be potential treatment options.