Pediatric leukemia is the most common cancer among children and adolescents.

Most cases of pediatric leukemia manifest acutely, necessitating prompt intervention and treatment upon symptom onset. So what should you do when you notice symptoms in your child?

We heard from Professor Hong Kyung-taek of Seoul National University Hospital's Department of Pediatrics about everything concerning pediatric leukemia.

● What is pediatric leukemia?

In Korea, cancers occurring in individuals under 18 years old are generally referred to as pediatric or adolescent cancers. Annually, approximately 1,200 to 1,500 cases of pediatric cancer are reported in Korea, with pediatric leukemia being the most prevalent. In 2020, a total of 372 new cases of pediatric leukemia were diagnosed, with 193 cases in those under 9 years old and 179 cases in those aged 10 to 19.

Pediatric leukemia is categorized into acute lymphoblastic leukemia and acute myeloid leukemia based on the origin of the affected blood cells. Acute lymphoblastic leukemia accounts for 70-80 percent of pediatric leukemia cases.

● What are the causes of pediatric leukemia?

Leukemia cells typically originate in the bone marrow, where blood is produced. Mutations in DNA, chromosomal structure, or abnormalities in cell proliferation lead to the transformation of normal blood cells into cancerous cells.

Unlike many adult cancers influenced by environmental factors like smoking or dietary habits, the causes of pediatric cancer are unclear, and predicting its onset is challenging.

Genetic predisposition accounts for around 10 percent of cases, while factors such as ionizing radiation, benzene, heavy metals, and other chemical agents are known to play significant roles in leukemia development. However, these factors alone cannot fully explain pediatric cancer occurrence, indicating the involvement of various probabilistic elements.

● How does pediatric leukemia manifest?

Leukemia cells proliferate uncontrollably, crowding out normal blood cells in the bone marrow. This can lead to decreased blood functions, resulting in symptoms such as pallor due to anemia, reduced physical abilities, bleeding tendencies due to decreased platelets, easy bruising, compromised immune function due to decreased white blood cells, and susceptibility to infections.

Additionally, proliferating leukemia cells can invade organs like the central nervous system, liver, spleen, lymph nodes, and testes, causing related symptoms. While leukemia cell invasion of the central nervous system often remains asymptomatic, rare cases may present symptoms like headaches due to increased intracranial pressure.

Other symptoms may include severe bone pain in the legs or lower back, occasionally leading to misdiagnosis as orthopedic or rheumatic conditions.

● What tests are conducted to diagnose pediatric leukemia?

The diagnosis of pediatric leukemia, like adult leukemia, typically requires a bone marrow examination. The bone marrow, located within the hard bones, is where hematopoiesis occurs. Common sampling sites include the pelvic bones, considered the safest for marrow aspiration.

While adults often undergo marrow aspiration in a prone position, pediatric patients may lie supine to ensure continuous monitoring of respiration during sedation.

Bone marrow examination usually causes minimal disruption to bone growth and relatively mild pain, with recovery typically within days. However, pediatric patients require careful monitoring to prevent respiratory complications associated with sedation.

● What are the treatment methods?

Pediatric leukemia, being a systemic disease where cancer cells spread via the bloodstream, requires a different approach from solid tumor removal through surgery. Timely initiation of treatment upon diagnosis is crucial due to frequent emergencies.

The primary treatment method involves chemotherapy, where anticancer drugs are administered. In cases of localized invasion, such as the central nervous system or testes, radiation therapy may be necessary.

For acute lymphoblastic leukemia, the standard treatment involves intensive therapy for approximately 6 to 10 months, followed by maintenance therapy for 2 to 3 years. However, aggressive treatment approaches, including hematopoietic stem cell transplantation, may be necessary for poor-prognosis cases or those with inadequate initial response to therapy.

Recent advancements include immunotherapeutic approaches utilizing various immune cells for the treatment of acute B-lymphoblastic leukemia, offering hope for previously challenging cases of relapse or resistance and exploring less toxic treatment modalities.

For acute myeloid leukemia, intensive short-term use of potent drugs aimed at suppressing bone marrow function is the strategy, with hematopoietic stem cell transplantation considered when the prognosis is poor. Stem cell transplantation is more commonly performed in acute myeloid leukemia than in acute lymphoblastic leukemia.

Recent data suggest cure rates exceeding 85 percent for acute lymphoblastic leukemia and over 60 percent for acute myeloid leukemia.

● How is post-treatment care managed?

Around 15 percent of pediatric leukemia patients experience relapse during or after treatment, often in the bone marrow but also potentially in the central nervous system or testes. Hence, post-treatment follow-up involves regular examinations and blood tests to monitor for relapse and observe for treatment-related complications.

● How can health be managed at home?

Healthy nutrition is crucial for pediatric leukemia patients, particularly to manage potential weight gain resulting from steroid use in acute lymphoblastic leukemia. Despite appetite loss and oral discomfort during intensive treatment phases, frequent small meals aid in maintaining nutritional status. Adequate hydration and light physical activity, such as walking, are also important for muscle maintenance.

● Lastly, any message for pediatric leukemia patients and their families?

Pediatric leukemia, like other childhood cancers, is not the fault of the child or the family but a societal challenge that requires collective support and treatment. While the treatment journey is challenging, advancements in cancer therapeutics aim to minimize the impact on children's growth and development, striving for healthier outcomes.

Trusting in children's remarkable resilience, parents should never lose hope and continue to provide positive energy alongside medical professionals throughout this challenging journey.