Some people diagnosed with blood cancer, particularly slow-growing forms, may not need treatment straight away, and some may never need it. In such cases, doctors often recommend “watch and wait,” also known as “active monitoring” or “active surveillance.” This approach is considered when symptoms are not troublesome, and there’s no immediate benefit to starting treatment. While watch and wait is a safe option that avoids the physical side effects caused by many types of blood cancer treatment, it can be a stressful experience for patients.

Regular appointments with the doctor will be necessary to check general health and symptoms, specifically to monitor whether the blood cancer remains stable or starts to progress. Treatment may be recommended at a future date if needed.

Active monitoring is often recommended for slow-growing (chronic) blood cancers with few or no worrying symptoms. It is an option for conditions like chronic lymphocytic leukaemia (CLL), follicular lymphoma, hairy cell leukaemia, and several others. Doctors only recommend this approach if delaying treatment won’t affect the patient’s quality of life and prognosis. There is no evidence overall that early treatment, when there are no symptoms, improves outcomes for some types of blood cancer. Instead, doctors recommend saving treatment for later when it will have the best impact. Currently, about 27,000 people in the UK are on active monitoring, representing around 13% of everyone living with blood cancer. Each year, around 5,000 people begin active monitoring. (i)

Chemotherapy is the use of potent drugs or chemicals, often in combinations and given at regular time intervals, to kill or damage the blood cancer cells in the body. The chemotherapy drugs must be toxic enough to kill the blood cancer cells, it is therefore a harsh treatment option. All chemotherapy drugs interfere with cancer cells’ ability to grow or multiply. However, the drugs toxicity can harm the healthy cells as well which results in unpleasant side effects.

Side effects of chemotherapy(ii) tend to vary from person to person and can vary based on the amount or type of chemotherapy drugs. Some side effects can include:

• Increased risk of infection
• Breathlessness
• Bruising easily
• Diarrhoea
• Fertility issues
• Mouth sores/ulcers
• Hair loss

Despite possible side effects, the ultimate goal of chemotherapy treatment is to damage or kill the blood cancer cells so there’s either no sign of illness (remission) or the disease’s progress is slowed. Chemotherapy can produce long-term remission or outright cure for many people, depending on the blood cancer type and the severity of the disease.

Chemotherapy is one of the most common treatments* for specific types of leukaemia such as acute lymphoblastic leukaemia (ALL). Chemotherapy treatment for leukaemia comes in different forms, which can include taking regular medication, injections or an intravenous drip into your bloodstream. 

Immunotherapy, also known as biological therapy, uses the body’s own immune system to eradicate the cancer. It can be used alone or with other treatments and is standard for some cancers while still in trials for others.

The immune system is designed to defend against disease-causing germs such as viruses and bacteria, as well as against cancer cells, with the ultimate goal to keep us healthy. However, cancer can survive unchecked in the body because the immune system doesn’t recognise cancer as different. There are several different types of immunotherapies available to treat blood cancers.

Types of Immunotherapies:

1. Monoclonal Antibodies (MABs)

Monoclonal antibodies are lab-made substances that act like the body’s natural antibodies – antibodies are proteins made by the immune system that help identify and fight off harmful invaders e.g. bacteria and viruses. They recognise and attack specific proteins on cancer cells, helping to destroy them. Some MABs can also deliver chemotherapy directly to cancer cells or make them more visible to the immune system. They often have names ending in “mab,” like Rituximab.

More information under Targeted Therapies below.

2. CAR-T Cell Therapy

CAR-T cell therapy involves taking a patient’s T cells (a type of immune cell), modifying them in a lab to better fight cancer, and then infusing them back into the patient. This therapy is available for some types of leukaemia and lymphoma and is being tested for other cancers.

More information can be found on the NHS website or through our Research Blog.

An example of a CAR-T therapy drug available is: Tisagenlecleucel (Kymriah®): A CAR T cell therapy targeting CD19; approved for certain children and young adults with ALL. (iii)

3. Checkpoint Inhibitors

Checkpoint inhibitors are drugs that help the immune system recognise and attack cancer cells by blocking proteins that prevent immune responses. The use of these for leukaemia (especially acute myeloid leukaemia) is still limited and based on early clinical trials.

nclude drugs such as pembrolizumab (Keytruda) and nivolumab (Opdivo).

4. Immunomodulators

Immunomodulators are substances that adjust the immune system’s activity. They can either enhance or suppress immune responses, aiding in the treatment of infections, autoimmune diseases, and cancers. In cancer therapy, they help the immune system recognise and attack cancer cells.

These agents improve disease management by enhancing immune cell activity, inhibiting cancer cell growth, or modifying immune-regulating proteins.

Examples include:

• Interferons: proteins like interferon alfa-2a and alfa-2b, used for certain leukemias.
  1. Interferon alfa-2a (Roferon®-A): Targets the IFNAR1/2 pathway; approved for certain patients with hairy cell leukemia and Philadelphia chromosome-positive chronic myeloid leukemia (CML).
  2. Interferon alfa-2b (Intron A®): Targets the IFNAR1/2 pathway; approved for certain patients with hairy cell leukemia and aggressive follicular non-Hodgkin lymphoma.
• Thalidomide and Lenalidomide: drugs for multiple myeloma.
• Cytokines: proteins that act as molecular messengers which play an important role in the immune system Researchers have created synthetic versions, like aldesleukin, to treat cancer. These synthetic cytokines enhance the body’s natural ability to fight cancer.

The are many ongoing studies into how cytokines act in leukaemia and how to make them a potential treatment target.

5. Vaccines to Treat Cancer

Cancer vaccines help the immune system recognise and attack cancer cells in people who already have cancer. Unlike traditional vaccines that prevent disease, these are still in early research stages and mostly available through clinical trials.

Targeted cancer drugs are one of the main treatment options for leukaemia. These work by ‘targeting’ the specific changes in cancer cells that help them to survive and grow; these changes are typically not present in normal / healthy cells.(iv)

Targeted cancer drugs are grouped depending on how they work, these include:

1. Monoclonal antibodies (MABs)

Antibodies are substances that occur naturally in the body and have a role in fighting infections.

Monoclonal antibodies are artificial antibodies that are made in a laboratory. When given as treatment they work by recognising specific proteins found on the surface of the blood cancer cells. Much the same as antibodies produced by the healthy immune system to eradicate disease-causing viruses etc, the artificial antibodies seek out the cancer cells, and help to eradicate them.

Monoclonal antibodies may work in different ways. Some interfere with signals that a cancer cell needs to survive or divide. Others work by carrying a chemotherapy drug directly to a cancer cell.

Monoclonal antibody drugs all have names that end in “mab”. For example, one of many monoclonal antibody therapies available is: Rituximab (Rituxan®): Targets the CD20 pathway; approved for certain CLL patients, including as a first-line therapy.

2. Cancer growth blockers

These targeted cancer drugs are also referred to as cancer growth inhibitors. There are many different type of cancer growth inhibitors that work in different ways. Our cells make chemicals called growth factors that function to control cell growth. Some growth factors work by telling cells how to specialise and some make cells grow and divide into new cells and then some tell cells to stop growing or to die. The chemicals work by binding to receptors on the cell surface and so communicating to the cell what to do.

Cancer growth blockers work by blocking these signals, specifically the growth factors that trigger cancer cells to divide and grow. A lot of research is focused on all the different routes that can be blocked.

Cancer growth blockers all have names ending in “ib”. Examples are: ibrutinib and imatinib (a type of tyrosine kinase inhibitor-TKIs). An example of a cancer growth blocker used for first-line treatment is: Venetoclax (Venclyxto®):  is a cancer growth blocker that targets BCL-2, a protein preventing cancer cell death, thereby promoting apoptosis in leukaemia and other cancer cells. Used to treat CLL and AML.

3. PARP inhibitors

ARP, short for poly-ADP ribose polymerase, is an enzyme in our cells that aids in repairing damaged cells.

As a cancer treatment, PARP inhibitors prevent PARP from repairing cancer cells, leading to cell death. Researchers initially investigated these drugs for cancers with existing repair issues, particularly those with mutations in the BRCA genes.

Currently there are no approved PARP inhibitors for leukaemia treatment. These are currently being studied for the use in blood cancers.

PARP inhibitors all have names ending in ‘arib’: for example olaparib, talazoparib, rucaparib and niraparib.

Radiotherapy is a treatment that uses radiation to destroy cancer cells.

Radiotherapy can be used to treat all types of blood cancer but more commonly used to treat Hodgkin lymphoma or Non-Hodgkin lymphoma.

Radiotherapy uses high-energy rays, such as x-rays, to destroy the blood cancer cells. Radiotherapy works by damaging the genetic material (DNA) within cells, which prevents them from growing and multiplying. Although the radiotherapy is directed at cancer cells, it can also damage nearby healthy cells. When radiotherapy is used for blood cancer treatment, it’s usually part of a treatment plan that includes drug therapy.

The treatment usually involves regular daily hospital visits to receive the radiotherapy but will not require a hospital stay. It may take several weeks to complete a course of radiotherapy.

Radiotherapy for leukaemia tends to be used in cases where leukaemia is causing bone pain, swollen lymph nodes or an enlarged spleen. The treatment may also be used if the stage of leukaemia is more advanced.

Blood stem cells are produced in the bone marrow to become all the different types of blood cell the body requires. The blood stem cells are constantly dividing and maturing into different types of blood cells, replacing older and worn-out blood cells in the body.

Healthy stem cells are needed to live.  When cancer or its treatments destroy stem cells, stem cell transplantation (SCT) may be the best option. SCT can also be used when treatments are limited or have failed, to replace damaged cells and reset bone marrow for healthy cell production. For example, chemotherapy can eliminate cancerous cells, and SCT can then replenish the bone marrow with healthy, unaffected cells. Stem cell transplantation (SCT), also known as a bone marrow transplant, is a procedure in which a patient receives healthy stem cells to replace faulty stem cells.

Stem cell transplants can be used to treat certain types of cancer, such as leukaemia, lymphoma, myeloma, and neuroblastoma, and other blood and immune system diseases that affect the bone marrow.^iiiiv

Before SCT, the patient receives high doses of chemotherapy, and sometimes radiation therapy, to prepare the body for transplantation. This is called “conditioning treatment.” After the stem cells are infused into the patient’s bloodstream, they travel to the bone marrow and begin the process of forming new, healthy blood cells including white blood cells, red blood cells and platelets. This process is called “engraftment.”

The main types of SCT are:

• Autologous transplantation uses the patient’s own stem cells. These cells are removed, treated and returned to his or her own body after a conditioning regimen.

Allogeneic transplantation uses stem cells from a donor. A donor may be a family member or someone who is not related to the patient.

Surgery is rarely used to treat blood cancers, although a small number of people with lymphoma need to have their spleen removed.

Research studies involving testing new drugs and treatments using patients are called clinical trials. Clinical trials are important, because they are the only way to develop new treatments or improve existing treatments.