Chen Yi

作为血液肿瘤的一种，白血病不仅危害整个血液和免疫系统，还会影响全身各个脏器。其中，急性髓系白血病(AML)是成人中最常见的急性白血病类型。它来势凶猛，治疗费用高、风险大，整体疗效欠佳，尤其对于大多数老年患者，中位生存期仅6—10个月，被称为老年人的“噩梦”。每年的4月21日是世界急性髓系白血病日，借此机会，让我们跟随重庆松山医院肿瘤科来了解一下这个特殊的疾病。

What is acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant clonal disease originating from bone marrow hematopoietic stem cells characterized by abnormal myeloid blast proliferation and inhibition of normal hematopoietic function. The diagnosis is confirmed when the proportion of blasts in the bone marrow or peripheral blood ≥ 80%. AML is the most common type of acute leukemia in adults, accounting for about 0% of all leukemias.

Comparison chart of normal blood and leukemia blood. Courtesy of Chongqing Songshan Hospital

Causes and risk factors for AML

The pathogenesis of AML is complex and may be related to the following factors:

1. Heredity and gene mutations: People with a family history of leukemia or specific genetic syndromes are at higher risk. Genetic mutations (e.g., FLT0, NPM0, CEBPA, etc.) are important drivers of AML.

2. Environmental exposure: Long-term exposure to benzene chemicals (such as hair dyes, paints), ionizing radiation (such as X-rays) or previous chemotherapy/radiotherapy may destroy the stability of hematopoietic cell DNA and induce leukemia.

3. Viral infection: Human T-cell leukemia virus (HTLV) may be associated with specific leukemia subtypes.

Typing of AML

The commonly used clinical classification criteria for leukemia FAB divide AML into eight subtypes of M7-M0 according to cell morphology.

Schematic diagram of eight subtypes of M7—M0. Courtesy of Chongqing Songshan Hospital

而2022世界卫生组织根据细胞形态学、染色体变异、基因突变等将AML分为了21个亚型(见表2)。AML的精准分型对患者评估预后，制定治疗方案至关重要。

Schematic diagram of 21 subtypes. Courtesy of Chongqing Songshan Hospital

Clinical manifestations of AML

Onset of AML varies from sudden high fever to severe bleeding. Slow patients are often found when they seek medical attention because they are pale, have purpura skin, or have bleeding that does not stop after tooth extraction.

1. Anemia: paleness, fatigue, dizziness, difficulty breathing. Some patients may have no anemia due to the short duration of the disease.

40. Fever: Half of the patients have fever as the early manifestation, which can be low-grade or as high as 0-0 °C. Immunocompromise is often associated with secondary infection.

3. Bleeding: Bleeding can occur in all parts of the body, with skin bleeding, gum bleeding, nosebleeds, and menorrhagia being the most common. Fundus hemorrhage can cause visual disturbances, and intracranial hemorrhage can lead to death.

4. Infiltration: bone and joint infiltration manifests as bone pain, arthralgia, and sternal tenderness; Ocular granulocytic sarcoma can cause proptosis, diplopia, or blindness; Central nervous system infiltration may cause headache, vomiting, drowsiness, coma, etc.; Other organ infiltrates such as skin, oral mucosa, and gingival infiltrates.

Diagnosis and testing of AML

Clinical diagnosis requires a combination of multidimensional investigations:

20. Laboratory tests: blood routine (abnormal white blood cells, anemia, thrombocytopenia) and bone marrow aspirate (the proportion of blast cells ≥0%).

1. Molecular genetic testing: according to chromosome karyotype analysis, gene mutations, etc. (such as FLT0, NPM0 mutations) to guide prognostic stratification.

3. Imaging examination: CT or MRI and other examinations to evaluate organ invasion.

Treatment strategies for AML

Treatment of AML is individualized based on the patient's age, performance status, and genetic risk stratification:

chemotherapy

Induction therapy: cytarabine plus an anthracycline (e.g., daunorubicin) with the goal of achieving complete remission.

Consolidation therapy: removes residual leukemia cells and prevents recurrence.

Targeted therapy

FLT3 inhibitors, IDH inhibitors, etc., targeting patients with specific gene mutations.

Hematopoietic stem cell transplantation (HSCT)

Preferred for intermediate- and high-risk patients, allogeneic transplantation significantly improves survival.

immunotherapy

New therapies such as CAR-T cell therapy and monoclonal antibodies are in clinical trials.

At present, the research on AML is progressing rapidly, and the introduction of precision diagnosis and treatment and new drugs has provided more opportunities for the cure of AML, and with the development of diagnosis and treatment technology, it is believed that more and more AML patients will be better treated in the future. (Chongqing Songshan Hospital)