Chemotherapy for bowel cancer

What is chemotherapy?

Chemotherapy is a term used to refer to medicines that can destroy cancer cells. Chemotherapy medications can be given in a variety of ways, including into a vein (intravenously) by injection, intravenously with a pump, or in tablet form taken by mouth. Each medication is usually targeted at a specific type of cancer, and each medicine has specific doses and schedules for its use. Chemotherapy can be given in a variety of situations.

Primary chemotherapy is used when bowel cancer is advanced and has already spread to different parts of the body. In this situation, surgery cannot be used to eliminate the cancer, so the best option is to be treated with chemotherapy. This may shrink tumours, alleviate symptoms, and prolong life.

Adjuvant chemotherapy is when chemotherapy is given after the cancer is surgically removed. The surgery may not eliminate all the cancer, so the adjuvant chemotherapy treatment is used to kill any cancer cells that may have been missed, such as cells that may have spread to the liver or elsewhere.

Neoadjuvant chemotherapy is chemotherapy given before surgery. Chemotherapy medications may be given before surgery in order to shrink the tumour so that the surgeon can completely remove it with fewer complications. Chemotherapy is also sometimes given with radiation, as it can make the radiation more effective.

Your specialist will discuss with you the best treatment strategy for your situation.

Chemotherapy medicines used for bowel cancer

5- Fluorouracil (5-FU) has been the first-choice chemotherapy medicine for bowel cancer for many years. It is often used in combination with the vitamin folinic acid (leucovorin), which makes 5-FU more effective. 5-FU is given intravenously. Recently, a tablet form of 5-FU has been developed, called capecitabine (Xeloda), which is often used for bowel cancer that has spread to other organs. Capecitabine is also being used as a neoadjuvant therapy with radiation therapy in patients with rectal cancers to enhance the effect of radiation.

Several new chemotherapy medications also are used for the treatment of bowel cancer that has spread. The National Institute for Health and Clinical Excellence (NICE) recommends irinotecan in combination with 5-FU and folinic acid (FA) as first line therapy, or irinotecan alone in subsequent therapy. A recommended alternative is oxaliplatin in combination with 5-FU and FA as first-line or subsequent therapy.

Several clinical trials are under way and other treatments may become available in the future. One area of interest is biological therapies (treatments that use medicines made from natural body substances) including bevacizumab (already licensed for use in the UK), cetuximab and panitumumab. The use of bevacizumab in combination with oxaliplatin and either 5FU or capecitabine for the treatment of advanced bowel cancer is currently under review by NICE.