Acute lymphoblastic leukemia (ALL), also called acute lymphocytic leukemia, is a type of blood cancer that starts in the bone marrow. A person with ALL may develop complications as a result of the disease itself or as a result of ALL treatments.

People with ALL can experience various complications. Some ALL complications are more common than others.

For example, ALL often leads to an underproduction of healthy blood cells, such as red blood cells, white blood cells, and platelets. It is common for people with ALL to develop conditions related to changes in their blood cell counts.

Complications that develop as a side effect of ALL treatments are more common for certain medications or drug combinations.

This article describes some complications of ALL.

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People with ALL have a higher risk of developing anemia. This happens when the rapidly dividing leukemia cells in the bone marrow crowd out the normal blood-producing cells, resulting in an underproduction of healthy red blood cells (RBCs).

This can lead to the following symptoms:

  • tiredness and fatigue
  • weakness
  • irregular heartbeat
  • shortness of breath
  • dizziness
  • headaches

Thrombocytopenia is a low platelet count in the blood. Platelets are tiny cell fragments that help with blood clotting and wound healing.

ALL increases a person’s risk of developing thrombocytopenia. This happens because the bone marrow overproduces leukemia cells, which then crowd out the platelets.

Because platelets play an important role in blood clotting, symptoms of thrombocytopenia may include:

People with ALL have an increased risk of prolonged or frequent infections. This can happen due to the cancer itself or from cancer treatments.

ALL affects white blood cells (WBCs) called lymphocytes. These cells are vital to the immune system. They help identify and destroy pathogens, such as bacteria and viruses.

In ALL, the bone marrow overproduces immature lymphocyte cells called lymphoblasts. These immature cells are unable to fight off infections and will never develop into lymphocytes.

Moreover, the overproduction of lymphocytes in the bone marrow crowds out other healthy blood cells, including other infection-fighting WBCs.

Some general symptoms of infection includeTrusted Source:

  • fever
  • chills
  • sore throat
  • cough
  • nasal congestion
  • stiff neck
  • gastrointestinal issues, such as vomiting or diarrhea
  • urinary issues, such as burning or pain during urination
  • abdominal pain
  • an area of redness, soreness, or swelling

As a 2022 study notes, individuals with ALL have an increased risk of developing blood clots during their initial chemotherapy treatment.

Researchers investigated a possible association between blood levels of a protein fragment called D-dimer at the time of ALL diagnosis and the subsequent risk of developing a blood clot. D-dimer forms when a blood clot dissolves in the body, so high levels indicate a possible blood clotting disorder.

Researchers found that high blood levels of D-dimer at the time of ALL diagnosis were associated with a fivefold increased risk of a blood clot during the first 100 days of cancer therapy.

According to the study, other factors that appear to increase the risk of blood clots in people with ALL include:

  • certain cancer treatments, such as high dose glucocorticoids and the chemotherapy drug asparaginase
  • frequent infections
  • inflammation from the cancer itself

ALL can spread to the central nervous system (CNS), which consists of the brain and spinal cord.

A 2023 study notes that ALL cells appear to use neural pathways to spread to the CNS. Some of these cells are capable of adapting to the CNS environment.

According to 2018 guidelines from the International Lymphoma Radiation Oncology Group, around 3% to 7% of people with ALL will have CNS involvement at the time of diagnosis.

However, around 50% of people with ALL will go on to develop CNS involvement if they do not have treatment to help prevent leukemia from spreading to their CNS.

ALL with CNS involvement does not often cause symptoms. If it does, symptoms may includeTrusted Source:

  • headaches
  • weakness
  • loss of balance
  • nausea
  • vomiting
  • blurred vision

Rarely, ALL with CNS involvement affects the cranial nerves in the head and neck. This could lead to the following symptoms:

  • issues with vision, such as double vision or blindness
  • deafness
  • facial numbness
  • swallowing difficulties

In refractory ALL, residual cancer cells remain in the bone marrow even after intensive treatment is completed.

In relapsed ALL, cancer remission is achieved but the cancer later returns to the bone marrow.

Refractory and relapsed ALL are typically more difficult to treat. They require a more intensive and complex treatment protocol from a specialist doctor or treatment team.

According to the U.K. nonprofit Leukaemia Care, around 20% to 40% of younger adults and around 50% to 60% of older adults will experience refractory ALL following their initial cancer treatment.

Around 15% to 20% of children and around 40% of adults will go on to experience a relapse of the disease.

The treatments for ALL may also lead to health complications, which include:

Tumor lysis syndrome

Chemotherapy causes the outer membrane of cancer cells to break down and releaseTrusted Source their cell contents. These contents include elements such as:

  • calcium
  • potassium
  • phosphorous
  • uric acid

If a large number of cancer cells break down very quickly, these elements can flood into the bloodstream, causing toxicity and kidney failure. The medical term for this is tumor lysis syndrome (TLS).

Receiving fluid therapy and steroids before chemotherapy treatment usually prevents TLS. If TLS does occur, treatment involves intensive fluid therapy.

Cytokine release syndrome

Cytokines are small proteins that act as chemical messengers between cells. They helpTrusted Source control the growth and activity of other immune cells and blood cells.

Immunotherapy causes immune cells to release cytokines into the blood. In cytokine release syndrome (CRS), the immune cells release large amounts of cytokines into the blood very quickly, causing severe and widespread inflammation.

According to the National Cancer InstituteTrusted Source, most cases of CRS cause a mild immune reaction, although some reactions can be severe or life threatening.

Hypofibrinogenemia

Asparagine is an essential amino acid that all cells need to create proteins and grow new cells. Asparaginase is an enzyme that breaks down asparagine.

Unlike healthy cells, cancer cells are unable to make their own asparagine. As such, asparaginase treatment can stop these cancer cells from growing and dividing.

However, as a 2019 study notes, asparaginase can cause hypofibrinogenemia. This is when the liver’s production of a protein called fibrinogen is reduced. Fibrinogen helps with blood clotting and wound healing. Symptoms may include easy bruising and prolonged bleeding.

The outlook for people with ALL varies and depends on factors such as age and how the cancer responds to treatment.

A relative survival rate helps give an idea of how long a person with a particular condition will live after receiving a diagnosis compared with those without the condition.

Between 2014 and 2020, the overall 5-year relative survival rate for ALL among children and adults combined was 72%Trusted Source. This means a person with the condition is 72% as likely to live for 5 years as someone without the condition.

»LEARN MORE:ALL survival rates

Acute lymphoblastic leukemia (ALL) is a cancer of the blood and bone marrow. Some of the most common complications of ALL are related to an underproduction of healthy blood cells. Examples include anemia, thrombocytopenia, and infections.

Complications may also arise as a result of ALL treatments. They include tumor lysis syndrome, cytokine release syndrome, and hypofibrinogenemia.

People can talk with their doctors about the potential side effects of their particular treatment and ways to identify them early.