The treatment depends on the staging of the cancer. When colorectal cancer is
caught at early stages (with little spread) it can be curable. However when it is
detected at later stages (when distant [[metastasis|metastases]] are present) it is
less likely to be curable.
Surgery remains the primary treatment while chemotherapy and/or radiotherapy
may be recommended depending on the individual patient’s staging and other
Surgical treatment is by far the most likely to result in a cure of colon cancer if the
tumor is localized. Very early cancer that develops within a polyp can often be cured
by removing the polyp at the time of colonoscopy. More advanced cancers typically
require surgical removal of the section of colon containing the tumor leaving
sufficient margins to reduce likelihood of re-growth. If possible, the remaining parts
of colon are anastomosed together to create a functioning colon. In cases when
anastomosis is not possible, a stoma (artificial orifice) is created. While surgery is
not usually offered if significant metastasis is present, surgical removal of isolated
liver metastases is common. Improved chemotherapy has increased the number of
patients who are offered surgical removal of isolated liver metastases.
Laparoscopic assist resection of the colon for tumour can reduce the size of painful
incision and minimize the risk of infection.
As with any surgical procedure, colorectal surgery can in rare cases result in
complications. These may include infection, abscess, fistula or bowel obstruction.
Chemotherapy is used to reduce the likelihood of metastasis developing, shrink
tumour 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 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)
Chemotherapy for metastatic disease. Commonly used first line regimens involve
the combination of infusional 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX)
with bevacizumab or infusional 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI)
Radiation therapy is used to kill tumor tissue before or after surgery or when
surgery is not indicated. Sometimes chemotherapy agents are used to increase the
effectiveness of radiation by sensitizing tumor cells if present. Radiotherapy is not
used routinely in colorectal cancer, as it could lead to radiation enteritis, and is
difficult to target specific portions of the colon, but may be used on metastatic
tumor deposits if they compress vital structures and/or cause pain. There may be a
role for post-operative adjuvant radiation in the case where a tumor perforates the
colon as judged by the surgeon or the pathologist. However, as the area of the prior
tumor site can be difficult (if not impossible) to ascertain by imaging, surgical clips
need to be left in the colon to direct the radiotherapist to the area of risk.
Bacillus Calmette-Guérin (BCG) is gaining prominence as a complementary
theraputic agent in the treatment of colorectal cancer. A review of results from
recent clinical trials is given in Mosolits et al.
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.