Growth factors are artificial (man-made) chemicals that encourage cells to divide and develop. There are lots of different growth factors that affect different types of cells. Your body makes growth factors naturally.
What are growth factors?
Granulocyte-colony stimulating factor (G-CSF) is produced in the body by the immune system and stimulates the formation of one type of white blood cell, the neutrophil. Neutrophils take part in the inflammatory reaction and are responsible for detecting and destroying harmful bacteria, viruses, and some fungi.
Some growth factors can also be manufactured in the laboratory. These can be used to stimulate the production of new cells in patients who need them.
Different types of G-CSF can be used:
- Lenograstim (Granocyte®)
- Filgrastim (Neupogen®)
- Lipegfilgrastim (Lonquex®)
- Pegylated filgrastim (Neulasta®)
Who needs growth factors?
Whether or not treatment with G-CSF is needed depends on:
- The type and stage of lymphoma
- The chemotherapy
- Whether neutropenic sepsis has occurred in the past
- Past treatments
- General health
Indications for G-CSF
There are several reasons why lymphoma patients may need to receive G-CSF. The reasons can include:
- Prevent neutropenic sepsis. Chemotherapy for lymphoma aims to kill lymphoma cells but some healthy cells might also be affected. This includes white blood cells called neutrophils. Treatment with G-CSF helps neutrophil counts to recover faster. It can be used to reduce the risk of neutropenic sepsis. They can also prevent delays or dose reductions in chemotherapy cycles.
- Treat neutropenic sepsis. Neutropenic sepsis is when a patient with a low level of neutrophils gets an infection which they cannot fight off and become septic. If they do not receive urgent medical treatment, it can be potentially life threatening.
- To boost stem cell production and mobilisation prior to a bone marrow transplant. Growth factors encourage the bone marrow to make stem cells in large numbers. They also encourage them to move out of the bone marrow and into the bloodstream, where they can be more easily collected.
How is it given?
- G-CSF is usually given as an injection under the skin (subcutaneously)
- The first injection is given in the hospital to monitor for any reactions
- A nurse can show the patient or a support person how to inject G-CSF at home.
- A community nurse might visit every day to give an injection, or it can be given at the GP surgery.
- They usually come in single-use, pre-filled syringes
- G-CSF injections should be stored in the fridge.
- Take the injection out of the fridge 30 minutes before it is needed. It is more comfortable if it is room temperature.
- Patients should measure their temperature every day and be alert for other signs of an infection.
Side effects of the G-CSF injections
The levels of white blood cells in the body will be tested regularly with a blood test while patients are having G-CSF injections.
More common side-effects
- Bone pain
- Hair loss
- Diarrhoea or constipation
Note: some patients can suffer from severe bone pain, especially in the lower back. This occurs as the G-CSF injections cause a rapid increase in neutrophils and inflammation response in the bone marrow. The bone marrow is mainly located in the pelvic (hip/lower back) area. This occurs when the white blood cells are returning. The younger the patient the more pain, as bone marrow is still quite dense when young. The older patient has less dense bone marrow and often less pain but not always. Things that can help ease the discomfort:
- Heat pack
- Loratadine: an over the counter antihistamine, that reduces the inflammatory response
- Contact the medical team to receive stronger analgesia if the above does not help
Report any severe side effects to your healthcare team.
Some patients can get an enlarged spleen. Tell the doctor if you have:
- A feeling of fullness or discomfort on the left side of the abdomen, just under the ribs
- Pain on the left side of the abdomen
- Pain at the tip of the left shoulder