Colon Cancer Treatment
Stage A and B are usually easily removed by surgery. A few decades ago the surgical techniques were improved as it was noticed that cancer cells have the tendency to spread horizontally first before they invade further vertically. With colon cancer surgery the surgeon removes the tumor with a wide margin to remove all the microscopic cell invasion and reconnects the colon where the tissue is healthy. There are problems with some more advanced stage B tumors where some microscopic cell invasion into local lymph glands may have taken place and these patients would follow more the survival pattern of stage C patients.
If the pathologist finds that the tumor has been incompletely removed and some tumor cells may have been left behind, then chemotherapy or radiotherapy would be given, just to be safe, which improves 5-year survival by 10 to 15% (increase from 65% to 80%).
With stage C the tumor itself is usually still operable, but many cancer cells are left behind in the regional lymph glands, because not all of them can technically be removed. Chemotherapy treatments are initiated as soon as the patient has recovered from the surgery to eradicate as much of these as possible.
Also, the medication levamisole (brand name: Ergamisol), which has immunostimulative properties, is given along with the chemotherapeutic agent 5-fluorouracil (brand names: Adrucil or Fluorouracil Roche).
The survival rate has been improved with this combination from 37% to 69% for stage C.
In stage D of colon cancer there is extensive involvement of regional lymph glands and there are often also several distant metastases present, first in the liver, but also in other organs. Unfortunately, at this stage, survival is only a few months to 1 ½ or 2 years. The immune system is has been overwhelmed by the cancer at this stage, which allows the disease to progress faster.
Prevention:
First degree relatives of a person with colon cancer have a 3- to 7- fold higher risk of developing colon or rectal cancer. All first degree relatives should therefore at least do the "stool for occult blood test" through their doctor's office. They may want to also go for an initial colonoscopy to screen for polyps.
If any are found, they must be removed. For most people this would make sure that they would not get rectal or colon cancer for 2 to 10 years. However, in familial polyposis and in the rare genetic syndromes Lynch I and Lynch II, where colon cancer is very common, the gastroenterologist in consultation with a geneticist should advise whether or not it might be wiser to do a preventative total colectomy as even 6 monthly colonoscopies may miss developing aggressive cancers. The same is true for end stage ulcerative colitis cases, where otherwise the cancer risk would be unacceptably high.
Generally speaking, there is a survival advantage of 22% for those asymptomatic patients where cancer was picked up by these screening techniques! It is thought that these asymptomatic patients have less invasive disease at the time of diagnosis and are simply placed higher on the 5-year survival rate table.
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