OVERVIEW

What is leukemia?

Leukemia is a malignant clonal disease originating from hematopoietic stem cells^[1]. It is characterized by "abnormal white blood cells," known as leukemia cells, which have a proliferation and survival advantage. These leukemia cells multiply and accumulate uncontrollably in the bone marrow, gradually replacing normal bone marrow hematopoiesis. As a result, red blood cells, white blood cells, platelets, and other components cannot be produced or function properly, leading to symptoms such as fever, infections, bleeding, anemia, and even multi-organ dysfunction or death.

In addition to physical suffering, leukemia patients may experience significant psychological distress. However, it is crucial not to lose hope in treatment. If a family member or friend is diagnosed with leukemia, please provide them with emotional support and encourage them to seek treatment actively.

What are the types of leukemia?

Acute leukemia: Primarily composed of immature, poorly differentiated leukemia cells. It can be further classified into acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML)^[2].

Chronic leukemia: The leukemia cells in chronic leukemia are more mature and differentiated than those in acute leukemia. It includes chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML)^[2].

Is leukemia common?

It is relatively rare. The overall incidence of leukemia in China is low, with approximately 3–4 cases per 100,000 people^[2].

Which department should I visit for leukemia?

Hematology, pediatric hematology, or pediatrics.

SYMPTOMS

What are the symptoms and clinical manifestations of leukemia patients?

1. Acute leukemia:

• Acute leukemia often has a sudden onset, with common initial symptoms including fever, progressively worsening anemia, easy bleeding, bone and joint pain, and enlargement of the liver, spleen, and lymph nodes^[1].
• A small number of patients may experience headaches, vomiting, neck stiffness, convulsions, vision loss, toothache, gum swelling, chest tightness (possibly caused by pericardial effusion), or paralysis of the lower limbs as initial symptoms^[1].
• Leukemia cells can also infiltrate various tissues and organs such as the lungs, pleura, kidneys, digestive tract, heart, brain, uterus, ovaries, breasts, parotid glands, and eyes, leading to dysfunction of the affected organs^[1].

2. Chronic leukemia:

• Early stages often show no obvious symptoms, and the condition is usually detected during routine health checkups, through abnormal blood test results for other illnesses, or due to an enlarged spleen^[1].
• As the disease progresses slowly, symptoms such as fatigue, low-grade fever, excessive sweating or night sweats, and weight loss may gradually appear^[1].

What oral changes occur in leukemia patients?

Leukemia is a malignant tumor of the hematopoietic system and can present with systemic and localized symptoms. Oral symptoms may be the earliest signs, such as gum bleeding, gum hyperplasia, oral mucosal bleeding, oral ulcers, gum necrosis, bad breath, and difficulty swallowing^[1].

If these symptoms persist without an obvious cause, they should be taken seriously, and medical attention should be sought promptly.

Why are leukemia patients prone to bleeding?

In healthy individuals, blood flows within blood vessels. When a vessel is damaged, blood leaks into surrounding tissues or exits the body, causing bleeding. The human body has three hemostatic systems—platelets, the coagulation system, and blood vessel walls. The bleeding tendency in leukemia patients stems from issues in these systems.

• Platelets: Due to the influence of leukemia cells, the number of platelets decreases, and their quality is impaired, which is the primary cause of bleeding in leukemia patients^[1].
• Coagulation system: Certain types of acute leukemia (e.g., acute promyelocytic leukemia, acute monocytic leukemia) release substances that activate the coagulation system, depleting clotting factors while also activating the fibrinolytic system, leading to a hypocoagulable state and severe bleeding. This condition is called "disseminated intravascular coagulation" (DIC), a highly fatal complication in leukemia patients.
• Blood vessel walls: Leukemia cells can extensively infiltrate blood vessel walls, damaging their integrity and normal contraction function, preventing proper constriction and resulting in prolonged bleeding.

Why are leukemia patients prone to infections?

Infections are common at the onset of leukemia and during chemotherapy-induced bone marrow suppression. Major causes include reduced white blood cell counts, impaired neutrophil function, compromised skin and mucosal barriers, long-term use of broad-spectrum antibiotics leading to microbial imbalance, weakened immune function, and the use of immunosuppressants (which, as the name suggests, suppress immune responses, lowering immunity and increasing infection risk)^[2].

Why do leukemia patients develop anemia?

Early-stage leukemia patients may not exhibit anemia, but as the disease progresses, red blood cell and hemoglobin levels inevitably decline. The primary cause is bone marrow suppression of red blood cell production due to leukemia cell infiltration and chemotherapy^[1]. Additional factors such as blood loss, hemolysis, deficiency in hematopoietic nutrients, and reduced erythropoietin production can worsen anemia.

CAUSES

What are the causes of leukemia?

The exact cause has not been fully determined, but current research suggests it may be associated with the following factors:

• Biological factors: Primarily viral infections and immune dysfunction. Studies have found that adult T-cell leukemia (ATL) is caused by human T-cell lymphotropic virus type 1 (HTLV-1), which is contagious and can spread through breastfeeding, sexual contact, and blood transfusions^[1].
• Physical factors: The leukemogenic effects of ionizing radiation (including X-rays, gamma rays, etc.) have been confirmed. The risk of developing leukemia depends on radiation dose, duration of exposure, and age^[1].
• Chemical factors: Long-term exposure to certain chemicals, such as benzene and benzene-containing solvents, may lead to leukemia. The exact mechanism remains unclear but may involve chromosomal abnormalities^[1].
• Genetic factors: Individuals with a family history of leukemia may have a higher risk. In identical twins, if one develops leukemia, the other has about a 1/5 chance of developing it^[1].
• Other blood disorders: Certain blood diseases, such as lymphoma, myelodysplastic syndromes, and multiple myeloma, may progress to leukemia^[1].

Who is at higher risk of leukemia?

People with a family history of leukemia are more susceptible than the general population.

• Those frequently exposed to ionizing radiation (e.g., X-rays, gamma rays), such as nuclear power plant workers, face an elevated risk.
• Individuals with prolonged exposure to harmful chemicals (e.g., benzene, benzene-containing products, paint, or indoor pollutants) are more vulnerable, particularly those in chemical manufacturing, construction, or dye industries.

Is leukemia hereditary?

Familial leukemia accounts for about 0.7% of cases, suggesting genetics may play a role^[1]. However, leukemia only has a potential hereditary tendency and is not guaranteed to be inherited.

Moreover, whether the clustering of leukemia in certain families is due to genetic factors, shared lifestyle habits, or environmental conditions remains inconclusive.

DIAGNOSIS

What tests are needed to diagnose leukemia?

Comprehensive and detailed physical examination: Check for signs of anemia, oral and gum conditions, skin and mucous membranes, palpate superficial lymph nodes for enlargement, examine the sternum for tenderness, and assess the liver and spleen for enlargement or masses.

• Blood tests^[3]: The most basic include complete blood count (CBC), biochemistry (such as serum alkaline phosphatase, lactate dehydrogenase, liver and kidney function), erythrocyte sedimentation rate (ESR), and immunological tests.
• Bone marrow examination: Includes bone marrow aspiration smear, biopsy, flow cytometry immunophenotyping, chromosomal and molecular biology tests.
• X-ray and CT scans: Include chest X-ray, chest or abdominal CT, etc.
• Ultrasound examination: Detects enlarged lymph nodes and organs like the liver and spleen.
• For patients suspected of central nervous system involvement, lumbar puncture and cerebrospinal fluid examination are required.

What is the "bone marrow aspiration" commonly performed in leukemia diagnosis and treatment?

Bone marrow aspiration, abbreviated as "bone marrow puncture," is a diagnostic procedure that involves extracting and analyzing a patient's bone marrow to assess the condition of the hematopoietic "factory"—the bone marrow.

During the procedure, the doctor typically asks the patient to lie on their side in a curled position. A needle is inserted into the bone above the hip to reach the marrow, and a sample is extracted for testing. Although it may sound painful, anesthesia is administered to minimize discomfort.

The bone marrow is the "production site" for various blood cells and the largest, most important hematopoietic tissue in the body. By examining the morphology and biochemical properties of marrow cells, as well as conducting chromosomal, molecular biological, immunological tests, and bone marrow biopsy pathology, doctors can evaluate the composition, distribution, quantity, and morphology of marrow cells, assess hematopoietic function, and diagnose leukemia.

Additionally, bone marrow findings help classify leukemia, evaluate disease progression, and monitor treatment efficacy.

Are leukemia and leukemoid reaction the same?

Leukemoid reaction is a condition where certain factors (infection, poisoning, tumor metastasis, acute hemolysis, drug reactions, etc.) stimulate the hematopoietic system, leading to increased white blood cells and a left shift in the nucleus. While blood test results may resemble leukemia, it is not true leukemia, and doctors must differentiate between the two.

Doctors typically distinguish them through bone marrow aspiration.

A leukemoid reaction always has an underlying cause, so identifying and addressing the primary condition is key.

TREATMENT

What are the current treatment methods for leukemia?

For the treatment of leukemia, drug therapy, surgical treatment, etc., are generally used:

• Drug therapy:
  • Chemotherapy: This is chemical therapy and the primary method for treating leukemia. Treatment involves intravenous injections, intramuscular injections, or oral administration of drugs that kill leukemia cells or inhibit their growth. Commonly used drugs include vincristine, daunorubicin, cyclophosphamide, etc.^[2]. Combination chemotherapy, using multiple chemotherapy drugs simultaneously, is typically employed. Depending on the patient's condition and physical constitution, side effects such as gastrointestinal reactions, liver and kidney damage, and hair loss may occur.
  • Molecular targeted therapy: Targeted drugs can precisely attack leukemia cells, inhibiting their proliferation while minimizing damage to normal cells. Common targeted drugs include imatinib mesylate and dasatinib^[1].
  • Immunotherapy: Immunotherapy enhances the body's immune function to further control leukemia cells. A common drug used is rituximab.
• Surgical treatment: If conditions such as cost and successful matching are met, patients may undergo hematopoietic stem cell transplantation to rebuild normal hematopoietic and immune functions, extending survival^[1].
• Radiation therapy: Also known as radiotherapy, it uses high-intensity radiation to kill tumor cells. In leukemia treatment, radiotherapy is usually an auxiliary option^[1].

Is leukemia an "incurable disease"?

In people's minds, leukemia is often considered an "incurable disease," akin to a death sentence. However, due to advancements in medical technology, significant breakthroughs have been made in leukemia treatment.

New treatment methods, such as improved chemotherapy regimens, molecular targeted therapy, induction differentiation therapy, and bone marrow transplantation, combined with better nutrition and hygiene conditions, can not only extend the survival of leukemia patients but also cure some cases, such as acute promyelocytic leukemia (M3) and chronic myeloid leukemia^[2].

A considerable number of patients can achieve a cure or maintain long-term disease stability, so active treatment is essential.

How is chemotherapy for leukemia conducted?

Leukemia treatment differs from that of common diseases, as it is a lengthy process. After diagnosis, the treatment course may last 2–3 years. However, depending on diagnosis, treatment drugs, regimens, and individual differences, the course may end within a year or extend beyond 3–5 years. If the disease remains in remission after 5 years, it is termed "clinical cure."

Chemotherapy is a critical component of acute leukemia treatment and is conducted in stages:

• Induction remission phase: The goal is to use sufficient chemotherapy drugs to quickly kill leukemia cells in the patient's body, restoring normal bone marrow test results.
• Post-remission treatment phase: Includes consolidation therapy, intensive therapy, maintenance therapy, prevention of extramedullary leukemia, and stem cell transplantation. The aim is to eliminate residual leukemia cells and reduce the risk of relapse.

What adverse reactions might leukemia patients experience during chemotherapy?

Most chemotherapy drugs lack ideal selectivity, so while killing tumor cells, they often cause varying degrees of damage to organs. These include:

• Short-term adverse reactions: Bone marrow suppression, gastrointestinal reactions, skin and mucosal damage, damage to vital organs (heart, liver, kidneys), and immune suppression.
• Long-term adverse reactions: Mainly the teratogenic and carcinogenic effects of chemotherapy drugs, though these are rare and should not deter patients from undergoing chemotherapy.

Does leukemia require lifelong chemotherapy?

Leukemia treatment generally lasts a long time. After diagnosis, the treatment course may take 2–3 years. Depending on the specific leukemia subtype, treatment regimen, and patient condition, the course may end within a year or extend beyond 3–5 years^[4].

Can leukemia relapse? Why does it relapse?

Yes, leukemia can relapse. Relapse is a major obstacle in leukemia treatment^[5].

Relapse primarily stems from residual leukemia cells in the patient's body. After treatments like chemotherapy or bone marrow transplantation, even when symptoms, signs, and test results are normal, some leukemia cells may remain, known as "minimal residual disease"^[5].

Can leukemia patients achieve complete remission again after relapse?

Once relapse occurs, standard-dose chemotherapy is unlikely to achieve complete remission again^[6].

Early relapse (<12 months) generally indicates a poor prognosis, necessitating exploration of new treatments, such as novel drugs or immunotherapy^[6].

For patients with longer remission periods (>12 months) before relapse, the disease is usually drug-sensitive, increasing the likelihood of remission. However, a cure is uncommon^[6].

What is the principle of hematopoietic stem cell transplantation for leukemia?

Hematopoietic stem cell transplantation involves transplanting one's own (autologous) or another's (allogeneic) stem cells into the body to rebuild hematopoietic and immune functions^[7].

Allogeneic transplantation: Transplants another's stem cells into the recipient to rebuild hematopoiesis and kill residual leukemia cells through graft-versus-leukemia effects.

Autologous transplantation: Involves collecting and freezing the patient's own stem cells, administering high-dose chemotherapy and total body irradiation, then thawing and reinfusing the stem cells to rebuild normal hematopoietic and immune functions, achieving a cure.

Do all leukemia patients need or qualify for hematopoietic stem cell transplantation?

Many patients mistakenly believe stem cell transplantation is the only treatment, going to great lengths to find matching donors or raise funds. However, it is not the sole option. Some leukemia subtypes can achieve long-term remission with chemotherapy alone^[6].

Some patients are ineligible for transplantation and rely on supportive therapies like blood transfusions and anti-infection measures, along with chemotherapy, to prolong remission and survival, even achieving long-term survival or cure.

When is hematopoietic stem cell transplantation suitable for leukemia patients?

Generally, if the patient achieves complete remission, is in good health, and has no high-risk prognostic factors, transplantation should be performed. Like other treatments, transplantation is a critical step in the process and should be done as early as possible after evaluation^[7].

What is graft-versus-host disease (GVHD)?

GVHD occurs when immune cells in the graft recognize the recipient's tissues as foreign and attack them. This happens because no two individuals (except identical twins) are immunologically identical. The transplanted T cells target the recipient's skin, esophagus, gastrointestinal tract, liver, and other organs, causing multi-system damage.

Can leukemia patients live normally after hematopoietic stem cell transplantation?

If the match is suitable, transplanted stem cells can function normally, allowing the patient to live like a healthy person. However, transplantation success depends on multiple factors, including pre-transplant chemotherapy, the transplant itself, post-transplant immune rejection, infections, and follow-up chemotherapy^[8].

Only after passing these stages and confirming donor gene expression, normal bone marrow, blood tests, and organ function after six months can the transplant be deemed successful.

Relapse can occur months or years post-transplant, influenced by disease type, immune response, complications, donor-recipient matching, and hospital expertise.

Long-term survival rates post-allogeneic transplantation are ~80% in adults and ~90% in children^[9].

What is the process of autologous hematopoietic stem cell transplantation?

Autologous transplantation involves mobilizing the patient's stem cells into the bloodstream, collecting and freezing them, administering high-dose chemotherapy/radiation, then reinfusing the stem cells to rebuild hematopoiesis and immunity^[7][8].

Do leukemia patients need chemotherapy after stem cell transplantation?

Typically, no. Chemotherapy is only resumed if relapse occurs. Stem cell transplantation is now an effective leukemia treatment^[2].

What factors affect leukemia prognosis?

Prognostic factors fall into two categories:

• Chemotherapy tolerance: Age, initial white blood cell count, disease subtype, organ function, physical status, medical history, etc.
• Chemotherapy sensitivity: Genetic features, treatment response, minimal residual disease levels, prior blood disorders, or exposure to radiation/chemotherapy.

DIET & LIFESTYLE

How Should Leukemia Patients Monitor Their Condition?

In daily life, leukemia patients should regularly undergo blood tests, blood biochemistry, bone marrow examinations, and closely monitor their physical condition and symptoms. Pay special attention to the following signs:

• Fever, sore throat, cough, swollen gums, or perianal pain may strongly indicate infection;
• Nosebleeds, gum bleeding, skin bruising, abdominal pain, red urine, black stools, or bloody stools are likely signs of severely low platelets;
• Swelling, weight gain, or reduced urine output may suggest impending kidney dysfunction;
• If any of the above symptoms occur, seek medical attention promptly to intervene early and prevent further progression of the disease.

What Dietary Precautions Should Leukemia Patients Take During and After Chemotherapy?

• Nutritional supplementation is essential. Increase intake of high-quality protein (e.g., lean meat, dairy, tofu) to maintain organ function;
• Vegetables and fruits are indispensable. Supplement with vitamin A (e.g., carrots, tomatoes) to boost immunity and抗癌能力 (anti-cancer ability);
• Don’t panic about anemia. Increase iron-rich foods (e.g., animal liver, black fungus, sesame) to alleviate symptoms;
• Appetizing, flavorful meals aid digestion. Eat smaller, more frequent portions.

What Lifestyle Precautions Should Leukemia Patients Take During and After Chemotherapy?

Prioritize hygiene and protection: Chemotherapy weakens immunity, increasing infection risks. Patients must maintain strict hygiene—wear masks daily, rinse after meals, and cleanse with sitz baths after using the toilet. Limit family visits to avoid cross-infection. Keep the environment clean by ventilating rooms regularly and cleaning frequently.

Maintain a positive mindset: Leukemia patients may feel pessimistic or lose hope. Listen to music, watch light entertainment to relieve stress. Communicate with family and friends to stay optimistic and build confidence in overcoming the illness.

PREVENTION

Can Leukemia Be Prevented?

The exact cause of leukemia is still unclear, making effective prevention difficult. However, the following measures may help reduce the risk of developing leukemia:

• Avoid consanguineous marriages to lower the likelihood of children developing leukemia.
• Actively treat blood system disorders such as lymphoma and multiple myeloma to prevent progression into leukemia.
• Practice self-protection by avoiding exposure to harmful physical or chemical substances. This primarily includes avoiding prolonged exposure to high doses of ionizing radiation, as well as repeated or long-term contact with benzene, benzene-containing compounds, paints, and harmful chemicals from renovation pollution. If occupational exposure is unavoidable, ensure proper personal protective measures.
• Certain anti-cancer drugs and immunosuppressants may trigger leukemia and should be used cautiously. Follow medical advice strictly and never alter medication methods without authorization.
• High-risk individuals should undergo regular health checkups and monitor early symptoms of leukemia to detect potential health risks promptly.