Chemotherapy for Rhabdomyosarcoma
All patients with rhabdomyosarcoma (RMS) will get chemotherapy at some point. Even if it appears that the cancer was removed completely by surgery, without chemotherapy it is likely to come back.
Chemotherapy (chemo) is the use of drugs to treat cancer. Chemo is systemic therapy, meaning that the drugs enter the bloodstream and go throughout the body to destroy cancer cells. This makes chemo useful for killing RMS cells that have spread to other parts of the body, even if they can’t be seen.
After surgery, any tiny deposits of RMS that remain can often be destroyed by chemo. If larger areas of tumor remain after surgery (or if surgery couldn’t be done for some reason), chemo (along with radiation) can often shrink these areas. In some cases it may shrink the tumor enough that surgery can remove the remaining tumor completely.
Drugs used to treat rhabdomyosarcoma
A combination of chemo drugs is used to treat patients with RMS. The drugs used depend to some extent on which risk group the child is in (described in the section How Is Rhabdomyosarcoma Staged?). Some drugs can be taken by mouth, but most are given IV (injected into a vein).
The main chemo drugs used to treat children in the low-risk group are vincristine and dactinomycin (also known as actinomycin-D). This combination is often referred to as VA. Sometimes cyclophosphamide is added as well. This 3-drug combination is referred to as VAC.
The VAC regimen is the most common combination used for the intermediate-risk group. Irinotecan or topotecan may be added as well. Other drugs used to treat RMS include ifosfamide, etoposide, and doxorubicin.
The same drugs are also used for children in the high-risk group (which includes children with metastatic disease), but these drugs have not been shown to be as successful in this group. New drugs and drug combinations are continually being studied by researchers. It is hoped that they will improve the survival rate in the high-risk group.
Doctors give chemo in cycles, which is usually treatment on 1 or 2 days in a row, followed by days off to give the body time to recover. For RMS, chemo is typically given once a week for the first few months, and then less often. The total length of treatment usually ranges from 6 months to a year.
Possible side effects
Chemo drugs attack cells that are dividing quickly, which is why they often work against cancer cells. But other cells in the body, such as those in the bone marrow (where new blood cells are made), the lining of the mouth and intestines, and the hair follicles, also divide quickly. These cells are also likely to be affected by chemo, which can lead to side effects.
Children tend to have less severe side effects from chemo than adults and often recover from side effects more quickly. This is why doctors can often give them higher doses of chemo to kill the tumor.
The side effects of chemo depend on the type of drugs, the doses, and how long they are taken. Possible side effects can include:
- Hair loss
- Mouth sores
- Loss of appetite
- Nausea and vomiting
- Increased chance of infections (from having too few white blood cells)
- Easy bruising or bleeding (from having too few blood platelets)
- Fatigue (from having too few red blood cells)
These side effects tend to go away once treatment is finished. There are often ways to lessen these side effects. For example, drugs can be given to help prevent or reduce nausea and vomiting. Be sure to ask your doctor or nurse about medicines to help reduce side effects, and report any side effects your child has so they can be managed effectively.
Along with the risks above, some chemo drugs can have specific side effects (although these are relatively uncommon). For example:
Cyclophosphamide and ifosfamide can damage the bladder, causing blood in the urine. The risk of this happening can be lowered by giving the drugs with plenty of fluids and with a drug called mesna, which helps protect the bladder. These drugs can also damage the ovaries or testicles, which might affect fertility (the ability to have children).
Vincristine can damage nerves. Some patients may notice tingling and numbness, particularly in the hands and feet. This often goes away or gets better once treatment is stopped, but it could last a long time in some people.
Recent studies have shown that children under the age of 3 years are more likely to have liver damage from chemotherapy. Doctors now use lower doses for any child younger than 3 years old.
Some chemo drugs can also increase the risk of developing a second type of cancer, usually a form of leukemia, years after the RMS is cured. But this is rare, and the importance of chemotherapy in treating RMS far outweighs this risk.
For more on some of these possible long-term side effects, including fertility issues and second cancers, see the section Possible Late and Long-term Side Effects of Treatments for Rhabdomyosarcoma.
For more on chemotherapy, see the Chemotherapy section of our website.
Last Medical Review: November 20, 2014 Last Revised: November 21, 2014