What is Leukemia?
Leukemia is a cancer of the blood-forming tissues in the body, including the bone marrow and the lymphatic system.
Leukemia typically involves white blood cells. White blood cells are potent infection fighters; typically, they grow and divide in an organized manner as the body needs them. However, in leukemia patients, this is not the case.
It is commonly believed that leukemia occurs when certain blood cells undergo changes (mutations) in their genetic material or DNA. A cell’s DNA holds instructions that tell it what to do. Typically, DNA instructs the cell to grow at a certain rate and to die at a specific time. In leukemia, mutations signal the blood cells to keep growing and splitting.
In these cases, blood cell production gets out of control. Over time, those abnormal cells can replace healthy blood cells in the bone marrow, leading to a decrease of healthy platelets, white blood cells, and red blood cells, resulting in the signs and symptoms of leukemia.
Leukemia classification.
Physicians classify leukemia based on the speed of progression and the types of cells involved.
Leukemia is classified as follows based on speed:
- Acute leukemia: In acute leukemia, the abnormal blood cells are immature blood cells (blasts). They cannot perform their normal functions and they multiply rapidly; therefore, the disease quickly worsens. Acute leukemia requires a timely and aggressive treatment.
- Chronic leukemia: There are many types of chronic leukemias. Some produce too many cells, while others produce too few. Chronic leukemia involves more mature blood cells. These blood cells replicate and accumulate very slowly, and they can work normally for a while. Some forms of chronic leukemia do not cause any early symptoms, so they may go unnoticed or undiagnosed for years.
The following classification is based on cell type.
- Lymphocytic leukemia: This type of leukemia affects the lymphoid cells (lymphocytes) that form the lymphoid or lymphatic tissue. The lymphatic tissue is part of the immune system.
- Myelogenous leukemia: This type of leukemia affects the myeloid cells. These cells create red blood cells, white blood cells, and platelet-producing cells.
Types of leukemia.
- Acute lymphocytic leukemia: This is the most common type of leukemia in young children. Adults can also be affected by acute lymphocytic leukemia.
- Acute myelogenous leukemia: Acute myelogenous leukemia is a common type of leukemia. It affects both children and adults. Acute myelogenous leukemia is the most common type of acute leukemia in adults.
- Chronic lymphocytic leukemia: If you have chronic lymphocytic leukemia, the most common chronic leukemia in adults, you may feel well for years without needing treatment.
- Chronic myelogenous leukemia: This type of leukemia mainly affects adults. A person with chronic myelogenous leukemia may have few or no symptoms for months or years before entering a phase where leukemia cells grow more rapidly.
- Other types of leukemia: There are other rare types of leukemia, such as hairy cell leukemia, myelodysplastic syndromes, and myeloproliferative disorders.
Symptoms.
The symptoms of leukemia can vary depending on the type of leukemia.
The signs and symptoms of leukemia include:
- Fever or chills.
- Persistent fatigue, weakness.
- Frequent or severe infections.
- Unexplained weight loss.
- Swollen lymph nodes, enlarged liver or spleen.
- Easy bruising and bleeding.
- Recurring nosebleeds.
- Tiny red spots on the skin (petechiae).
- Excessive sweating, especially at night.
- Bone pain or sensitivity.
Leukemia in Mexico.
According to GLOBOCAN, Mexico recorded 6,955 new cases and 4,786 deaths related to this disease in 2020, making it one of the top ten cancers in both incidence and mortality nationwide.
In recent years, out of every 100 hospital discharges for cancer (malignant tumors) in the population aged 0 to 19, 73 were related to lymphoid, hematopoietic, or related tissues. Lymphoid leukemia is part of this classification , which alone accounts for 61% (24,851) of all cancer patient discharges (40,679) in this population group.
Leukemia in Latin America.
In Mexico, 5,000 to 6,000 children are diagnosed with cancer every year. Roughly 5 out of 10 of those children are diagnosed with leukemia. Most children are diagnosed with late-stage leukemia (around 70%, or 7 out of 10).
In Peru, around 1,300 children are diagnosed with cancer every year. Leukemia accounts for 1 out of every 3 cases of childhood cancer.
In Colombia, around 6,218 children were diagnosed with cancer in 2018. Acute lymphoblastic leukemia (ALL) is the most common type of childhood cancer in the country.
Patients with acute leukemias in Latin America often face challenges due to delayed diagnoses, leading them to seek medical help at advanced stages of the disease, thus complicating treatment.
Leukemia worldwide.
Acute leukemia typically occurs in 3-6 patients per 100,000 inhabitants per year.
Acute lymphoid leukemia is more common in children, and is the most prevalent cancer in childhood, accounting for approximately 25% of all cancers in children under the age of 15. Myeloid leukemia is more common in adults, and its incidence is rising.
As individuals age, the survival prognosis worsens, especially after 60 years of age. Prognosis is also unfavorable when diagnosing childhood acute leukemia (especially lymphocytic leukemia) in children younger than 1 or 2 years of age and in those over 15.
Treatments
Chemotherapy: Special drugs are used to shrink or kill cancer cells. These medications can come in the form of oral tablets or injections administered into your veins, or in some cases, both methods may be used.
Bone marrow transplant: A procedure that replaces defective stem cells in a person’s bone marrow.