Once colon surgery has been performed, the patient will be examined to make sure the cancer has been properly treated and additional treatments may be ordered to make sure it does not return. However, these really depend on the stage of the cancer when it was: (a) diagnosed and (b) operated on.
The following may apply after surgery:
Stage 0 – Tests will need to be done to evaluate the surrounding lymph nodes, liver, and lungs to see if they are free of cancer cells. This is usually a precautionary measure, as is the case with stage 0 colon cancer; it has not metastasized (spread) through the lining of the colon and usually requires a single operation to remove it.
Stage I – This is where cancer cells have grown through various layers of the colon, but have not yet spread outside the colon wall. A colectomy (surgery performed to remove part or all of a patient’s colon) is usually sufficient without requiring any additional treatment for the patient.
Stage II – The cancer has metastasized to nearby tissues, but not to lymph nodes. A colectomy is usually used to treat this stage of cancer; however, if the cancer is near the margins of the exercised tumor, or if it has blocked the colon, then chemotherapy may be used to help treat it.
Chemotherapy will generally include: 5-FU (fluorouracil, adrucil, and 5-fluorouracil), capecitabine, leucovorin, or oxaliplatin which can be used alone or in combination. Radiation therapy may also be given to the area of the abdomen where the cancer was removed.
Stage III – The cancer has now metastasized to the lymph nodes around the abdomen area; however, it does not show further metastasis to other parts of the body. Once again, colectomy will be the order of the day, followed by chemotherapy (5-FU, capecitabine, leucovorin, or oxaliplatin) for a period of up to 6 weeks.
Radiation therapy can also be used to kill any cancer cells that may remain from the body. Chemotherapy and radiation therapy (without surgery) may also be ordered if the patient is considered not strong enough to withstand surgery.
Stage IV – Cancer has metastasized through the colon, to lymph nodes, and to distant tissues and organs in the body, including: the peritoneum (the thin, continuous layer of tissue that lines the abdominal and pelvic cavities), the liver, lungs, and the ovaries. (in the case of female patients). Usually at this stage, surgery alone will not be enough.
Chemotherapy may be used to help shrink the tumor before surgery and radiation therapy given after surgery to kill cancer cells from the body. However, after stage IV surgery, the prognosis (life expectancy) of a patient is not particularly good, with less than 5% survival in the last 5 years, unlike survival rates from diagnosis of Colon cancer in earlier stages are 90% or more.