Colon cancer is diagnosed and treated by the GI Division of Premier Medical Group.
Colon cancer is diagnosed and treated by the GI Division of Premier Medical Group.
Colon cancer forms in the large intestine (colon), which is the lower part of your digestive system. It is the second leading cause of cancer deaths in the US. When found in its early stages, colorectal cancer is highly treatable. In many cases, colorectal cancer can be prevented.
According to the American Cancer Society, the rate of new colorectal cancer cases and deaths from the disease has been shrinking by about 2% a year over the last decade. To a large extent, this is because more people are receiving periodic colorectal cancer screenings.
Most colorectal cancers begin as tiny clumps of abnormal cells on the lining of the colon or rectum, called adenomatous polyps. These polyps are benign (non-cancerous), but have the potential to become malignant (cancerous). The transformation is slow-occurring over several years and the polyps usually produce no recognizable symptoms to alert patient and doctor.
People who develop numerous adenomatous polyps have a greater-than-normal risk of colorectal cancer. This is referred to as adenomatous polyposis syndrome, and tends to run in families. Such cases are called familial adenomatous polyposis (FAP). The cancer usually occurs before age 40.
Another possible cause for colorectal cancer is called hereditary nonpolyposis colorectal cancer (HNPCC) syndrome, which also runs in families. In this type, colon cancer can develop without polyps.
Researchers have determined that the HNPCC syndromes are associated with a genetic abnormality. They have identified the gene and people at risk can be identified genetic screening. Once a person is determined to carry the abnormal gene, counseling is recommended along with regular screenings for cancerous tumors.
Other causes that put people at risk for colorectal cancer can be:
Colorectal cancer does not always show symptoms. Beginning at age 50, and earlier if there is a family history, it is very important to have regular examinations, called colorectal screenings, or colonoscopies.
An early symptom of colorectal cancer may be rectal bleeding, and sometimes in only small amounts which can only be found in stool specimen testing.
Other symptoms may include:
If you experience any of these symptoms, it is vital to see your health care provider as soon as possible to guarantee proper diagnosis and treatment. When colorectal cancer is found in the early stages, treatment can be very effective.
The first step to a diagnosis is a complete medical history. This may include a digital rectal exam. At this time he or she may take a stool sample and check it for blood. If your health care provider finds concerning symptoms, the next step would be to schedule a diagnostic workup. This may include:
By the time colorectal cancer is diagnosed, it has often been growing for several years, first as a non-cancerous polyp (adenoma) and later as cancer. Research indicates that by age 50, one in four people has polyps.
Adenocarcinomas are the most common type of colon cancer. This type of cancer originates in the glands and accounts for about 90-95 percent of colorectal cancers. There are two sub-types, mucinous and signet ring cell. The mucinous subtype comprises about 10-15 percent of adenocarcinomas while the signet ring cell subtype comprises less than 0.1 percent of adenocarcinomas. The bigger the gland (adenoma), the more probable it is to become cancerous. If your doctor finds a polyp larger than two centimeters (size of a nickel) it is more likely to be cancerous than a much smaller polyp.
Leiomyosarcoma is a type of colon cancer that develops in the smooth muscle of the colon. Although this type is responsible for less than 2 percent of colorectal cancers, it has a fairly high chance of metastasizing.
Lymphomas are the rarest in the colon cancer family. They generally originate in the rectum rather than the colon, but if they begin in another part of the body, they are likely to spread to the colon.
Melanoma is rare as a colon cancer. Melanoma commonly begins in another area of the body and can end up spreading to the colon, but rarely begins there.
Tumors can be idle or they can be aggressive. Large and small cell (neuroendocrine) tumors are aggressive and (carcinoid) tumors are lazy or idle.
Other factors that may affect getting colon cancer are:
There are four types of treatment available for colon cancer:
Surgery: the primary treatment of colon cancer, is the removal of all or part of the colon (polyps are generally removed during colonoscopy). There are several types of surgical procedures that the doctor will consider, depending on the stage of the colon cancer.
Resection: This is done when the cancer is large, and he or she removes the cancerous portion of the colon along with some healthy tissue around it (colectomy). The two ends are then attached together. At this time the lymph nodes may also be removed.
Colostomy: If the doctor is unable to attach the two ends together, a stoma or opening is made on the outside of the body for waste to pass through. A bag is attached and is emptied by the patient. In some cases the colostomy can be reversed.
Local excision: When the cancer is found very early, the doctor may be able to remove it by putting a tube through the rectum, into the colon and cutting it out.
Chemotherapy: also known as chemo, is a term used by doctors to refer to a class of drugs (antineoplastic drug or a combination of such drugs) that work by killing off fast growing cancer cells, but it can’t always tell the difference between cancer cells and fast growing healthy cells. This results in low blood counts (both red and white), and because of this, makes the patient vulnerable to infections. This is a powerful tool in fighting many types of cancers.
Chemo can be administered in three ways:
There are two types of chemotherapy: Adjuvant, and Neoadjuvant. Adjuvant is administered after cancer is removed, to kill any cancer cells that may have been missed. Neoadjuvant is given before surgery to shrink any tumors so the surgeon is able to remove it with fewer complications.
Radiation is a powerful tool that can be used to treat colon cancer and it is also used to treat rectal cancer. When used before surgery, radiation can reduce the size of any tumors. This treatment uses high-energy x-rays or other types of radiation to stop any cancer cells from growing.
Targeted therapy is the use of particular drugs that identify and attack specific cancer cells. This type of therapy does not harm the normal cells.
Monoclonal antibody therapy is also a targeted type of therapy. It isolates proteins which are specific to colon cancer and targets them.
Radiofrequency ablation is when the surgeon uses a very specialized probe. This probe has small electrodes that will kill the cancer cells. The probe can be inserted through an incision in the groin or abdomen and is performed in the hospital under general anesthesia. If it’s inserted into the skin, it can be done with a local anesthetic.
Cryosurgery is a type of treatment that is used to freeze and kill cancerous tissue.
Q: When should I seek medical care?
A: If you notice any of the following symptoms, you should see your health care provider as soon as possible.
Q: Will folic acid help prevent colon cancer?
A: Folic acid is a water-soluble vitamin that is often added to cold cereals, flour, breads, pasta, bakery items, cookies, and crackers. Some studies believe that by taking folic acid supplements it could lower the risk of colon cancer, but it does not seem to help patients who have already been diagnosed with the disease.
Q: What are the stages of colon cancer?
Q: What is an adenoma?
A: It is a benign or non-cancerous polyp or growth in the lining of the large intestine. They can be signs of colon and rectal cancer.
Q: Can diet affect colon cancer?
A: The best way to avoid colon cancer is by eating a high-fiber, low fat diet, and by maintaining a healthy body weight by keeping active.
Q: Does blood in my stool mean I have colon cancer?
A: While early signs of colon cancer can be rectal bleeding, there are other reasons such as hemorrhoids which can cause blood in your stool. The most important thing you can do is get a proper diagnosis.