B-cell acute lymphoblastic leukemia (B-cell ALL) is a type of blood cancer that affects B lymphocytes, which are white blood cells found in the bone marrow that develop into cells and aid in immunity.
B lymphocytes are a type of white blood cell that forms in the bone marrow. In normal circumstances, B lymphocytes are supposed to develop into cells that aid in immunity. However, in this disease, they transform into leukemia/cancer cells that survive longer and replicate more rapidly than regular cells. They accumulate in the bone marrow and then spread through other organs through the bloodstream.
Common signs and symptoms of patients with B-cell ALL are as follows:
- Loss of appetite
- Bruising/bleeding including heavy menstrual bleeding in women
- Unexplained weight loss
- Swollen or painful abdomen
- Bone and joint pain
- Recurring infections
- Red or purple spots on the skin
- Night sweats
- Enlarged lymph nodes in the neck, armpits or groin
B-cell ALL may spread to sites such as the brain and spinal cord (central nervous system [CNS]), chest, liver, kidney, skin, ovaries and eyes to cause other symptoms. In B-cell ALL, CNS involvement occurs in five to eight percent of patients. Signs and symptoms of CNS involvement include headache, seizures, weakness, vomiting and difficulty balancing. When cancer spreads to the chest, it may cause symptoms such as difficulty breathing, chest pain or pressure.
What are the possible causes of B-cell ALL?
The underlying cause of B-cell acute lymphoblastic leukemia (B-cell ALL) is still unclear in the majority of cases. However, in children with B-cell ALL, chromosomal abnormalities include changes in the number and translocations of the chromosomes that result in a rearrangement of the genes.
Possible causes of B-cell ALL may include:
- If patients have received chemotherapy or radiation medication for cancer in the past, their risk of B-cell ALL is higher.
- Additionally, receiving chemotherapy and radiation at the same time may also increase the risk of B-cell ALL.
- Research suggests that factors such as lifestyle, genetic disorders or chromosome abnormalities may play a role in developing B-cell ALL.
- Pesticides, magnetic exposure and overstimulation of the immune response during the first years of life are thought to be related to an increase in the occurrence of B-cell ALL.
- Moreover, children with Down syndrome and other genetic disorders are more likely to develop B-cell ALL.
What are the treatment options for B-cell ALL?
The ideal outcome of treatment for patients with B-cell acute lymphoblastic leukemia (B-cell ALL) is to achieve a complete remission with chemotherapy, followed by a bone marrow transplant or maintenance treatment, whichever is the best for them.
Chemotherapy is a common treatment used to either kill the cancerous B-cells or stop them from dividing. It is commonly used in induction therapy but can also be used as consolidation and maintenance therapies.
Different treatment phases of B-cell ALL may include:
- This phase aims to kill all or a majority of the cancerous B-cells in the blood and bone marrow to restore normal blood cell production, which has been disrupted by the presence of the cancerous B-cells.
- In this phase, any remaining leukemia in the body, such as in the brain or spinal cord, is ideally destroyed.
Relapsed or refractory reinduction chemotherapy:
- This is given to patients with relapsed cancer or those who did not respond to induction therapy (refractory).
Preventive therapy for the central nervous system (sometimes called intrathecal chemotherapy):
- During any of the treatment phases, additional treatment may be given to kill the cancerous B-cells located in the CNS.
- Chemotherapy drugs are often injected directly into the cerebrospinal fluid (CSF), which is fluid that is present around the spinal cord.
- This ongoing phase is intended to prevent any cancerous B-cells from multiplying again, with lower doses of therapy often given for years.
Apart from chemotherapy, below are the other B-cell ALL treatment options:
- Targeted therapy is treatment with drugs that attack specific abnormalities present in cancer cells that allow them to grow and thrive.
- These drugs do not simultaneously harm the healthy cells like conventional chemotherapy drugs.
- Targeted therapy may be used during or after chemotherapy.
Stem cell transplantation (SCT):
- This can be used as consolidation therapy in patients who have a high risk of relapse or for treating relapse when it occurs.
- SCT helps patients reestablish a healthy bone marrow.
- Patients receiving SCT are given high doses of chemotherapy or radiation to destroy any cancerous B-cells.
- The blood-forming stem cells are then infused to restore the bone marrow of patients.