For many cancer patients, the best treatment option is chemotherapy, which uses strong drugs to kill off fast-growing cancer cells and can lower the chance of the cancer coming back. Despite its effectiveness, however, chemotherapy comes with a lot of risks. The drugs kill not only cancer cells, but sometimes healthy ones as well. One particularly dangerous side effect is the loss of blood cells that play important roles in your immune system. But how do we restore these blood cells and improve patients’ health?
Stem Cells
After a cell is newly formed, certain genes are then expressed, differentiating it into a specialized cell—whether that is a blood cell, nerve cell, or others. A cell that has not yet been differentiated is known as a stem cell, and for cancer treatment, blood-forming stem cells are especially important. These cells can differentiate into:
- White blood cells, which are crucial to your immune system by fighting infections
- Red blood cells, which circulate oxygen throughout your body
- Platelets, which allow blood to clot and prevent excessive bleeding
Stem Cell Transplants With Chemotherapy
Using blood-forming stem cells to replenish what chemotherapy killed off can help avoid the harsh side effects. But how do we obtain these stem cells?
- Autologous transplants: stem cells come from the cancer patient, but there is a risk of unintentionally transplanting cancer cells
- Allogenic transplants: stem cells come from someone else, but they must be a close enough match so the patient’s immune system does not view the new cells as foreign
- Syngeneic transplants: stem cells from the patient’s identical twin, if they have one
Once stem cells have been transplanted, they travel to the patient’s bone marrow, where all blood cells are produced. They then help regenerate the normal cells that the chemotherapy killed.
Mini-transplants are a method of treatment with allogenic transplants. A patient is given a lower dose of chemotherapy so not all of the bone marrow is damaged, and some cancer cells are killed. This ensures that the patient’s suppressed immune system will accept the donor’s stem cells. Mini-transplants are better for older patients who may also have other health problems. They are also not recommended for patients with fast-growing cancers, as the lower doses of chemotherapy will not be effective enough.
Tandem transplants are another treatment with autologous transplants. A patient is given a high dose of chemotherapy followed by a transplant of their own stem cells, eliminating the risk of their body rejecting the cells. Once the patient has recovered, they will once again receive a high dose of chemotherapy and a subsequent stem cell transplant. This type of transplant can increase the chances of severe side effects due to it utilizing two transplants.
Concerns of Stem Cell Transplants
Stem cell transplants do not work for every form of cancer. The main types of cancers that are treated using stem cells are leukemia, lymphoma, multiple myeloma, and myelodysplastic syndromes. It can also be very expensive to pay for transplants and manage their side effects, making them inaccessible as a treatment plan for many cancer patients.
While we are eliminating one side effect of chemotherapy, other side effects can come from stem cell transplants. Short-term problems can include nausea, heavy fatigue, or hair loss. More severe long-term problems can include organ damage (known as graft-versus-host disease), secondary cancers, or bone and muscle weakness.
Ultimately, stem cell therapy is one of many treatments used along with chemotherapy to help patients beat cancer with minimal side effects. But like any cancer treatment, it comes with its own set of risks and side effects.
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Carroll CARES 