September 4 marks "World Leukemia Day," an initiative launched by the Acute Leukemia Advocates Network, CLL Advocates Network, CML Advocates Network, and Leukaemia Care. The day is dedicated to raising global awareness about leukemia, promoting efforts in prevention, diagnosis, treatment, and recovery. Leukemia, often called "blood cancer," is a complex disease with high treatment costs and the risk of relapse, placing a heavy burden on many families. However, through awareness and action on this day, we aim to break the silence and helplessness, and collectively ignite a beacon of hope for leukemia patients.

What is Leukemia?

Leukemia is a malignant tumor originating in the hematopoietic system, starting from hematopoietic stem and progenitor cells. It is characterized by an abnormal proliferation of leukemia cells in the bone marrow, which then infiltrates other tissues and organs, leading to the suppression of normal blood cell production. Leukemia can be classified into two main types based on cell differentiation and the natural progression of the disease: acute and chronic leukemia. Acute leukemia includes acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML), while chronic leukemia includes chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), and rarer forms of leukemia.

According to the Global Cancer Statistics Report of 2022, there were 487,000 new leukemia cases and 305,000 deaths worldwide in 2022, accounting for 2.4% of all cancer incidences and 3.1% of cancer deaths, ranking leukemia 13th in incidence and 10th in cancer mortality globally. The incidence, mortality, and geographical and ethnic distribution of leukemia vary significantly depending on the type. In China, epidemiological data show that leukemia has an annual incidence rate of 2.71 per 100,000 people. The rates for specific types of leukemia are as follows: AML (1.62 per 100,000), ALL (0.69 per 100,000), CML (0.36 per 100,000), and CLL (0.05 per 100,000), with other rare types accounting for 0.03 per 100,000. Among all types, AML has the highest incidence, followed by ALL and CML.

How is Leukemia Diagnosed and Evaluated?

Diagnosing leukemia involves a complex and systematic process, requiring a combination of clinical manifestations, physical exams, laboratory tests, and other diagnostic tools.

Acute leukemia often presents with rapid onset, with symptoms appearing within a few days to 1-2 weeks. Early signs may include high fever, progressive anemia, significant bleeding, or bone and joint pain. Chronic leukemia, on the other hand, has a longer course, and many cases are discovered incidentally during routine blood tests, such as finding elevated white blood cell counts or the unintentional detection of enlarged lymph nodes or spleen.

Bone marrow biopsy is a key step in diagnosing leukemia. By extracting bone marrow samples, physicians can observe the types and characteristics of cells to determine the presence of leukemia cells. Other tests include a complete blood count (CBC) and blood smear analysis. The CBC measures white blood cells, red blood cells, and platelets, providing a preliminary assessment of potential blood disorders. A stained blood smear, viewed under a microscope, allows for the evaluation of the shape and function of blood cells.

With advancements in molecular biology, techniques such as PCR and FISH can detect specific gene mutations or fusion genes within leukemia cells, helping to determine the leukemia subtype and prognosis.

What Are the Treatment Options for Leukemia?

Leukemia treatment is a comprehensive process that includes chemotherapy, radiotherapy, targeted therapy, and bone marrow transplantation.

For most patients with AML, chemotherapy is the standard treatment. Common drugs include cytarabine, daunorubicin, and anthracyclines, often used in combination. The goal of chemotherapy is to kill or inhibit the growth of leukemia cells while minimizing damage to normal cells. In recent years, targeted therapies have played an increasing role in AML, including FLT3 inhibitors, IDH1/IDH2 inhibitors, and BCL-2 inhibitors.

In ALL, significant progress has been made in immunotherapy, including CD19/CD3 bispecific antibodies, CD22 antibody-drug conjugates (ADCs), and CAR-T cell therapy. For intermediate- and high-risk acute leukemia patients, allogeneic hematopoietic stem cell transplantation is an effective treatment option. This involves transplanting healthy donor stem cells into the patient after preconditioning, allowing the re-establishment of normal blood and immune functions. For lower-risk patients, autologous stem cell transplantation may also be considered.

Chronic myeloid leukemia (CML) has seen rapid advancements in treatment since the introduction of the first tyrosine kinase inhibitor (TKI), imatinib, in 2001. Over the past 20 years, treatments have evolved from first-generation to third-generation TKIs and even combination therapies. Clinical data now show that long-term survival rates for CML patients are similar to those of the general population, suggesting that CML can be effectively managed, possibly cured, and treated as a chronic condition similar to diabetes or hypertension.

In chronic lymphocytic leukemia (CLL), in addition to BTK inhibitors, newer generations of BCL-2 inhibitors are emerging. Many drugs similar to BCL-2 inhibitors are in development, and targeted therapies have brought CLL treatment on par with CML, achieving long-term survival comparable to managing chronic diseases like diabetes or hypertension.

How Can Leukemia Be Prevented?

Although there is no definitive way to prevent leukemia, adopting a healthy lifestyle can help reduce the risk.

• Avoid harmful substances: Limit exposure to benzene and its derivatives, and avoid prolonged exposure to ionizing radiation. Workers exposed to radiation should take protective measures, particularly pregnant women and young children.
• Maintain a healthy lifestyle: Stick to a regular schedule, ensure adequate sleep, engage in physical activity, and boost immunity. Eat a balanced diet rich in fresh fruits and vegetables, and ensure food is sourced from safe, certified producers.
• Regular check-ups: High-risk individuals should undergo annual health screenings, including a CBC and peripheral blood smear analysis. Seek medical attention promptly if experiencing symptoms like fever, bleeding, enlarged lymph nodes, or chest pain, and undergo a blood test if necessary.

For leukemia patients, besides receiving standard treatments, daily care and rehabilitation are equally important. Patients and their families should closely follow medical advice, maintain a positive mindset, and lead a healthy lifestyle. In addition, they should take measures to prevent complications such as infections and bleeding, attend follow-up appointments regularly, and adjust treatment plans as needed to improve outcomes.

The establishment of World Leukemia Day aims not only to raise global awareness about leukemia but also to call for collective attention to this serious health challenge. Through public education and action on this day, we hope to advance leukemia prevention, diagnosis, treatment, and recovery worldwide.

With continuous advancements in medical technology and the emergence of new treatment options, the prognosis for leukemia patients is improving. Many are achieving long-term survival or even cure through standardized treatment. However, we must continue to push for more research and clinical breakthroughs to offer patients more precise and effective treatment strategies.

At the same time, we need to address the mental health and social support needs of leukemia patients. They require not only physical treatment but also emotional care and social support. We should create a supportive, caring environment for them, providing comfort and strength throughout their treatment journey.

In conclusion, World Leukemia Day is a day for us to unite and take action. Together, let’s shine a light of hope for leukemia patients and contribute to their health and happiness.