Chemotherapy for Osteosarcoma

Chemotherapy (chemo) is the use of drugs to treat cancer. The drugs are usually given into a vein or by mouth and can reach and destroy cancer cells throughout the body. Chemo is often used as part of treatment for osteosarcoma.

Most osteosarcomas do not appear to have spread beyond the main tumor when they are first found. But in the past, when these cancers were treated with surgery alone, the cancer would often come back in other parts of the body, where it would be very hard to control. Giving chemo along with surgery helps lower the risk of these cancers coming back.

Most osteosarcomas are treated with chemo before surgery (known as neoadjuvant chemotherapy) for several weeks. In some people with osteosarcoma in an arm or leg bone, this can shrink the tumor, which might help make surgery easier. Chemo is then given again after surgery (known as adjuvant chemotherapy) to kill any cancer cells left.

Chemo is given in cycles, with each period of treatment followed by a rest period to give the body time to recover. Each cycle typically lasts for a few weeks.

Which chemo drugs are used to treat osteosarcoma?

The drugs used most often to treat osteosarcoma include:

• Methotrexate
• Doxorubicin (Adriamycin)
• Cisplatin or carboplatin
• Ifosfamide
• Etoposide
• Cyclophosphamide
• Gemcitabine
• Topotecan
• Docetaxel

Usually, 2 or more drugs are given together. Some common combinations of drugs include:

• High-dose methotrexate, doxorubicin, and cisplatin (known as the MAP regimen), sometimes with ifosfamide and/or etoposide (MAPIE). This is used more often in children, teens, and young adults.
• Doxorubicin and cisplatin. This is used more often in older adults.

Many experts recommend that the drugs be given in very high doses when possible.

Possible side effects of chemo

Chemo drugs affect cells that grow fast. While cancer cells grow fast, other healthy cells in the body do too – for example, blood-forming cells, hair cells, and cells that make up the lining of our gut. Damage caused by these drugs on fast-growing healthy cells results in side effects. The specific side effects of chemo drugs depend on the type, dose, and the length of time they are given.

General side effects of chemo

Side effects common to many chemo drugs include:

• Nausea and vomiting
• Loss of appetite
• Diarrhea or constipation
• Hair loss
• Mouth sores

Chemo can damage the bone marrow, where new blood cells are made. This can lead to low blood cell counts, which can result in:

• Increased chance of infection (from having too few white blood cells)
• Easy bruising or bleeding (from low platelets)
• Fatigue or shortness of breath (from low red blood cells)

To lower the risk of serious infections, sometimes drugs called growth factors (such as filgrastim, also known as G-CSF) may be given along with the chemo to help the body make new white blood cells as quickly as possible.

Most of the side effects above tend to go away after treatment is finished. Often there are ways to make these side effects less severe. For example, drugs can be given to help prevent or reduce nausea and vomiting or to help get blood counts back to normal levels. Be sure to discuss any questions you have about side effects with the cancer care team and tell them about any side effects so that they can be controlled.

Long-term side effects of chemo

Chemotherapy can also have some longer-term side effects. For example, some drugs can increase the risk of later developing another type of cancer (such as leukemia). While this is a serious risk, it is not common, and the small increase in risk must be weighed against the importance of chemotherapy in treating osteosarcoma. For more on the possible long-term effects of treatment, see After Treatment for Osteosarcoma.

Side effects of certain chemo drugs

Some chemo drugs have specific side effects. For example:

The doctors and nurses will watch closely for side effects. Do not hesitate to ask the cancer care team any questions about side effects.

For more information on the possible late or long-term side effects of chemo, including infertility and second cancers, see Late and Long-term Effects of Childhood Cancer Treatment.