急性髓性白血病（AML）

About Leukemia

白血病is a type of cancer that affects the body’s white blood cells (WBCs).

Normally, WBCs help fight infection and protect the body against disease. But in leukemia, WBCs turn cancerous and multiply when they shouldn’t, resulting in too many abnormal WBCs, which then interfere with the body’s ability to function normally.

In acute myeloid leukemia (AML), too many immature white blood cells (called myeloid blasts) are made. These leukemia cells are abnormal and cannot mature into normal white blood cells. This type of leukemia affects 20% of kids with this cancer of the blood cells.

Thanks to advances in therapy and clinical trials, the outlook for kids with AML is promising. With treatment, most are cured.

Causes

AML的原因是未知的，虽然医生知道某些医疗状况可以增加孩子获得AML的风险。但是，只因为孩子有风险因素并不意味着他或她会得到AML。

Risks include inherited genetic problems such as唐氏综合症,神经纤维瘤病type 1, Fanconi anemia, Noonan syndrome, and other inherited bone marrow failure syndromes(IBMFS)。In addition, other non-inherited conditions such as preleukemia (also called myelodysplastic syndrome or MDS) and aplastic anemia can increase the risk of AML.

AML在被接受治疗的孩子中也更常见chemotherapy要么辐射。事实上，AML是预先经历癌症治疗的儿童中最常见的继发性癌症。

此外，一个具有相同双胞胎的孩子被诊断患有白血病之前，在6岁之前患有20％至25％的发展AML的几率。兄弟双胞胎和白血病儿童的其他兄弟姐妹也有两到四倍的平均发展它的平均风险。

Certain environmental factors can predispose a child to leukemia. For example, exposure to radiation (such as X-rays) prior to birth may trigger the disease in a developing fetus.

迹象和症状

AML is called “acute” because it tends to worsen quickly if left untreated. Chronic blood cancers, like chronic myelogenous leukemia (CML), tend to progress more slowly. However, the symptoms of all types of leukemia are generally the same and include:

• 疲劳和弱点
• 淋巴结肿大
• recurrent infections (like bronchitis or tonsillitis)
• 发热
• 易于瘀伤或瘀伤（轻松出血引起的皮肤上的微小斑点）
• bone and joint pain
• abdominal pain (caused by abnormal blood cells accumulating in organs like the kidneys, liver, and spleen)

Sometimes a child might have painless lumps that can be felt in the lymph nodes of the neck, underarm, or groin area. These lumps of leukemia cells (called chloromas) can develop anywhere in the body.

Diagnosis

AML的亚型根据细胞在显微镜下看的方式进行分类。如果医生怀疑白血病，孩子可能会接受包括：

• 血液测试。测试such as acomplete blood count,肝和肾功能面板，血液化学物质可以提供关于身体中正常血细胞数的重要信息以及器官正在运作的程度。还将在显微镜下检查血细胞以检查异常形状或尺寸，并确定儿童的AML的哪些亚型。
• 骨髓抽吸和活组织检查。In this procedure, the doctor inserts a needle into a large bone, usually the hip, and removes a small amount of bone marrow to examine it for abnormal cells.
• Imaging studies.这些可包括X射线，CT扫描，MRI或超声检查，以检查扩大的脾脏或肝脏，以及排除儿童症状的任何其他可能的原因。
• 腰刺穿。Also called a spinal tap, this procedure uses a hollow needle to remove a small amount of cerebrospinal fluid (the fluid surrounding the brain and spinal cord) for examination in a lab.
• 流式细胞仪测试。通过分析癌细胞的性质，医生可以确定孩子的白血病类型。这很重要，因为治疗在不同类型的白血病之间变化。
• Chromosomal tests.通过分析来自血液或骨髓的DNA，医生可以检查识别AML各种亚型的特定遗传变化。这很重要，因为治疗可能根据亚型而变化。
• Tissue typing or HLA (human leukocyte antigen) typing.If a child needs a stem cell transplant (also called a bone marrow transplant), this test helps doctors find a suitable stem cell donor. It works by comparing the proteins on the surface of a child’s blood cells with the proteins on a potential donor’s cells. The more “HLA markers” a child and donor share, the greater the chance that a transplant will be successful.

治疗

因为它可以如此迅速地进步，因为没有AML的分期系统。医生通常表征了新诊断或缓解的疾病。

治疗is divided into two phases. The goal of the first phase, called induction, is to kill as many cancer cells as possible and achieve remission (a state where there is no evidence of disease in the body). The second phase (called post-remission, consolidation, or continuation therapy) is designed to eliminate any undetectable leukemia cells.

Phases I and II of treatment may include the following therapies alone or in combination:

• Chemotherapy.这是使用特殊药物来杀死癌细胞。几种化疗药物通常组合以不同方式攻击癌细胞。
• 化疗通过腰椎穿刺。该程序，称为鞘内（IT）化疗，将化疗药直接递送到脑脊液中，癌细胞可以收集。
• All-trans retinoic acid (ATRA).This vitamin A treatment is sometimes given alongside chemotherapy to kids with acute promyelocytic leukemia (APL), a subtype of AML.
• Arsenic trioxide.This substance (an inorganic compound) is also used to treat kids with APL.
• Stem cell transplant (also called bone marrow transplant).该程序涉及用高剂量化疗破坏癌细胞和正常骨髓和免疫系统细胞，然后将健康供体干细胞重新介绍到体内。这些新的干细胞可以重建健康的血液供应和免疫系统。
• 临床试验。这些是研究研究，提供manbetⅹ 注册了普遍公众尚未使用的有希望的新治疗方法。孩子的医生将决定一个孩子是否是临床试验的好候选人。

应对

被告知孩子患有癌症可能是一种可怕的经验，并且癌症治疗的压力可能会为任何家族压倒。

Although you might feel like it at times, you’re not alone. To find out about support that may be helpful to you or your child, talk to your doctor or a hospital social worker. Many resources are available to help you get through this difficult time.

Reviewed by:Emi H. Caywood, MD
审查日期：2012年3月