Medications

The following chemotherapy drugs may be used at various points during therapy:

• 5-Fluorouracil (5-FU): This drug is given intravenously either as a continuous infusion using a medication pump or as quick injections on a routine schedule. This drug has direct effects on the cancer cells and is often used in combination with radiation therapy because it makes cancer cells more sensitive to the effects of radiation. Side effects include fatigue, diarrhea, mouth sores, and hand-and-foot syndrome (redness, peeling, and pain in the palms of the hands and the soles of the feet).
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• Capecitabine (Xeloda): This drug is given orally and is converted by the body to a compound similar to 5-FU. Capecitabine has similar effects on cancer cells as 5-FU and can be used either alone or in combination with radiation therapy. Side effects are similar to intravenous 5-FU.
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• Oxaliplatin (Eloxatin): This drug is given intravenously once every 2 or 3 weeks. Oxaliplatin has recently become the most common drug to use in combination with 5-FU for the treatment of metastatic rectal cancer. Side effects include fatigue, nausea, increased risk of infection, anemia, and peripheral neuropathy (tingling or numbness of the fingers and toes). This drug may also cause a temporary sensitivity to cold temperatures up to 2 days after administration. Inhaling cold air or drinking cold liquids should be avoided if possible after receiving oxaliplatin.
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• Irinotecan (Camptosar, CPT-11): This drug is given intravenously once every 1-2 weeks. Irinotecan is also commonly combined with 5-FU. Side effects include fatigue, diarrhea, increased risk of infection, and anemia. Because both irinotecan and 5-FU cause diarrhea, this symptom can be severe and should be reported immediately to a doctor.
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• Bevacizumab (Avastin): This drug is given intravenously once every 2-3 weeks. Bevacizumab is an antibody to vascular endothelial growth factor (VEGF) and is given to reduce blood flow to the cancer. Bevacizumab is used in combination with 5-FU and irinotecan or oxaliplatin for the treatment of metastatic rectal cancer. Side effects include high blood pressure, nose bleeding, blood clots, and bowel perforation.
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• Cetuximab (Erbitux): This drug is given intravenously once every week. Cetuximab is an antibody to epidermal growth factor receptor (EGFR) and is given because rectal cancer has large amounts of EGFR on the cell surface. Cetuximab is used alone or in combination with irinotecan for the treatment of metastatic rectal cancer. Side effects include an allergic reaction to the medication and an acnelike rash on the skin. Clinical trials are underway to evaluate this antibody for the treatment of localized rectal cancer.

Medications are available to alleviate the side effects of chemotherapy and antibody treatments. If side effects occur, an oncologist should be notified so that they can be addressed promptly.