Colorectal cancer medical therapy

Editor(s)-in-Chief: C. Michael Gibson, M.S.,M.D. [mailto:mgibson@perfuse.org] Phone:617-632-7753; Elliot B. Tapper, M.D., Beth Israel Deaconess Medical Center

Chemotherapy
Chemotherapy is used to reduce the likelihood of metastasis developing, shrink tumor size, or slow tumor growth. Chemotherapy is often applied after surgery (adjuvant), before surgery (neo-adjuvant), or as the primary therapy if surgery is not indicated (palliative). The treatments listed here have been shown in clinical trials to improve survival and/or reduce mortality rate and have been approved for use by the US Food and Drug Administration.


 * Adjuvant (after surgery) chemotherapy. One regimen involves the combination of infusional 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX)
 * 5-fluorouracil (5-FU) or Capecitabine (Xeloda®)
 * Leucovorin (LV, Folinic Acid)
 * Oxaliplatin (Eloxatin®)


 * Chemotherapy for metastatic disease. Commonly used first line chemotherapy regimens involve the combination of infusional 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) with bevacizumab or infusional 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) with bevacizumab
 * 5-fluorouracil (5-FU) or Capecitabine
 * Leucovorin (LV, Folinic Acid)
 * Irinotecan (Camptosar®)
 * Oxaliplatin (Eloxatin®)
 * Bevacizumab (Avastin®)
 * Cetuximab (Erbitux®)
 * Panitumumab (Vectibix)


 * In clinical trials for treated/untreated metastatic disease.
 * Bortezomib (Velcade®)
 * Oblimersen (Genasense®, G3139)
 * Gefitinib and Erlotinib (Tarceva®)
 * Topotecan (Hycamtin®)

Radiation therapy
Radiotherapy is not used routinely in colon cancer, as it could lead to radiation enteritis, and it is difficult to target specific portions of the colon. It is more common for radiation to be used in rectal cancer, since the rectum does not move as much as the colon and is thus easier to target. Indications include:
 * Colon cancer
 * pain relief and palliation - targeted at metastatic tumor deposits if they compress vital structures and/or cause pain
 * Rectal cancer
 * neoadjuvant - given before surgery in patients with tumors that extend outside the rectum or have spread to regional lymph nodes, in order to decrease the risk of recurrence following surgery or to allow for less invasive surgical approaches (such as a low anterior resection instead of an abdomino-perineal resection)
 * adjuvant - where a tumor perforates the rectum or involves regional lymph nodes (AJCC T3 or T4 tumors or Duke's B or C tumors)
 * palliative - to decrease the tumor burden in order to relieve or prevent symptoms

Sometimes chemotherapy agents are used to increase the effectiveness of radiation by sensitizing tumor cells if present.

Immunotherapy
Bacillus Calmette-Guérin (BCG) is being investigated as an adjuvant mixed with autologous tumor cells in immunotherapy for colorectal cancer.

Support therapies
Cancer diagnosis very often results in an enormous change in the patient's psychological wellbeing. Various support resources are available from hospitals and other agencies which provide counseling, social service support, cancer support groups, and other services. These services help to mitigate some of the difficulties of integrating a patient's medical complications into other parts of their life.