Colon treatment Examination and treatment

The colon is the name given to the last part of the intestine, which is about 6 feet in length and is Located Between The Small Intestine And The Rectum. The Colon Is Sometimes Called The Large intestine. The large intestine ends in the rectum.

Colon cancer and rectal cancer, commonly known as colorectal cancer, are the third most common form of cancer in Canada.

The risk of colorectal cancer increases with age. After 30 years, the risk is at least doubled every 10 years. The majority of physicians initiate screening tests at age 50. Men appear to be at a higher risk of developing colon cancer.

Screening is crucial because the faster the colorectal cancer is detected, the better the chances of recovery. Treatment is more effective in people with localized colorectal cancer. People who may be at increased risk of colorectal cancer are advised to consult their physician to decide which screening schedule is best for their situation.

The stage of tumor development is usually the best predictor of a prognosis. Cancers are usually classified into stages according to the size of the tumors and especially the degree of spread of the disease to other parts of the body. The stage in question depends mainly on the contamination of the lymph nodes. The lymph nodes are masses of cells of the immune system, having the shape of a bean, found throughout the body. They are connected to each other by their own network of vessels, the lymphatic system.Cancer often spreads to other organs through the lymphatic system. This spread of the disease from one part of the body to another is called metastasis.

In the case of colon cancer, stages 1 and 2 represent different levels of penetration of the colon wall. Stage 3 cancer has reached the nearby lymph nodes. Stage 4 cancer has spread to other parts of the body (metastases). The recurrent cancer recurs after treatment previously deemed successful. It often reappears in the liver or lungs rather than in the colon.

What are the Causes?

The causes of cancer are still poorly established. In some cases, the genes that determine the activity of a cell are mutated and begin to give instructions that lead to uncontrolled tissue growth. A single cancer cell divides millions of times and produces a tumor. Tumors develop their own blood vessels to ensure an oxygen supply. For more details on carcinogenesis (causes and progression of cancer), see the article “Cancer”.

By observing cancer prevalence rates, it is possible to predict who will be most at risk for colon cancer, and to develop individual prediction methods.

The main risk factor, which is the most obvious warning signal, is the presence of colorectal polyps. These are benign growths that appear inside the colon. The term “benign” means that these excrescences are not themselves cancerous. On the other hand, the presence of a large number of benign excrescences carries dangers, because some of them are likely to turn into cancerous tumors. Polyps are part of this last category.

The polyps have the shape of a small ball placed on a stem, which forms a protuberance in the inner wall of the colon. They can cause rectal hemorrhage, but the blood is usually masked in the stool. Each new polyp has a 2.5% risk of becoming cancerous in the first 5 years and 24% after 20 years. Larger polyps are more likely to turn into malignant tumors. Some people have more than one polyp.

The risk of polyps and colon cancer is greater in the following situations:

• an age greater than 50 years;
• smoking;
• alcohol consumption: people who smoke and drink alcohol are at risk 4 times higher than average;
• a low level of physical activity
• a diet high in meat, fat and protein;
• a history of ulcerative colitis or Crohn’s disease;
• a family history of polyps, colon cancer or cancer of the reproductive organs in women (ovarian, endometrial or breast cancer).
• obesity;
• past abdominal radiation treatments (eg an adult who has been treated with abdominal radiation for cancer during childhood).

Like most cancers, colon cancer seems to be partly explained by a genetic cause, partly by environmental factors, and partly by random factors. Some families have genes that promote the appearance of thousands of polyps, which is a high risk of colon cancer. Other families do not have this gene, but there is still an incidence of colon cancer higher than that of the general population. In the same way, people from families where this disease has never appeared can be struck by colon cancer.

What are the Symptoms and Complications?

Polyps and colon cancer can cause slow and constant hemorrhage in the colon. The blood is found in the stool, but is often invisible. Many other disorders can cause blood in the stool, but it is important to see a doctor. Often blood loss remains invisible, but their effect is felt in the form of iron deficiency anemia (iron deficiency). Postmenopausal men and women with symptoms of anemia should undergo a medical examination.

Colon cancer can cause vague symptoms such as weight loss or bowel movements, or may not cause any symptoms. Most often, colon cancer causes no symptoms until the stage of the disease is advanced. This is why screening plays a vital role.

What are the Diagnostics?

The search for occult blood is usually part of routine screening tests. This test requires that you give a stool sample in which the occult blood is sought. A positive test does not automatically mean that you have colon cancer. Your doctor will need to do other tests to determine why blood is in your stool.

Screening for colon cancer in people at high risk is based on colonoscopy . An endoscope , which is a flexible tube made of optical fibers, is used to observe the colon for bleeding, polyps or tumors. If growths are detected, the doctor takes a tissue sample ( biopsy ). On the other hand, he could also extract or completely destroy a polyp during the procedure. The examination is not painful, although it can be slightly unpleasant. You may be offered medications to help you relax during the procedure.

What Type of Treatment and Prevention are available?

There are 3 possible forms of treatment for colon cancer: surgery, radiotherapy and chemotherapy.

Surgery is the treatment generally recommended for curing colon cancer, but it is only suitable for people with stage 1 to 3 disease. If the condition is diagnosed at stage 3, then radiotherapy or chemotherapy is associated with surgery. This is also sometimes the case for stage 2 tumors.

Polyps can be extracted without surgery. To do this, the endoscope is provided with a cutting device.

The best way to prevent colon cancer is to avoid risky behaviors, such as smoking, and improve one’s diet. In addition, the correction of unhealthy lifestyle habits (losing weight to get closer to a healthy weight, quitting smoking or exercising more) helps reduce the risk.

It has been shown that a diet high in vegetables, fruit and fiber helps to prevent colon cancer. It could also be that calcium has a protective effect.

But above all, when there are risk factors, polyp screening is important. The risk of colon cancer is twice as high for people who have had polyps previously extracted than for others of their age. However, this risk is 8 times higher than normal for those in whom the polyps remain in place.

The treatment proposed by the gastroenterologist, the surgeon or the oncologist will differ according to the grade of evolution of the cancer .
The choice of care will be determined during a multidisciplinary consultation meetingduring which several doctors, surgeons, anatomopathologists and oncologists will review the medical file.
• When one is in the very localized lesion stage , that is to say that the cancer has not spread to neighboring organs, surgery alone will be chosen.
• When the cancer is infiltrating and reaches the lymph nodes, it is the surgical treatment that is recommended, withlymph node dissection, which is associated with ”  adjuvant chemotherapy  “.
• Finally, if colon cancer is metastasized , the treatment will consist of colon surgerysupplemented by surgery of the metastasized organs , followed or preceded by chemotherapy and sometimes targeted therapy .

What are the principles of rectal cancer treatment?

The treatment of rectal cancer differs from colon cancer in its management.
• At the localized stage , surgery is the basic treatment with a resection of the part of the affected rectum but also all supporting tissues around that contain the ganglia.
• From the moment the cancer is infiltrating , the surgery will be preceded or followed by radiotherapy and chemotherapy .

What is surgery treatment for colon cancer?

Colon surgery can be performed either by a “laparotomy” with a large incision in the abdomen, or “laparoscopy” with two small incisions, but only during early stage cancer.
The surgery will consist of removing the part of the colon where the cancer is located. To avoid leaving cancerous cells, the surgeon will have to remove a large part of the colon around the tumor mass. So if the cancer is at the level of the right colon, we will do a “right hemicolectomy” which includes the right colon and the right half of the transverse colon. If the cancer is at the level of the left colon, a “left hemicolectomy” will be done which includes the left colon and the left half of the transverse colon. If the cancer is at the sigmoid colon, there will be a “sigmoidectomy” that includes only the part between the end of the left colon and the beginning of the rectum. Sometimes when the cancer is too advanced and spreads over both parts of the colon, it will be necessary to perform a “total colectomy”.
After removing the part of the colon concerned, we will have torestore the continuity of the intestine by making an anastomosis between the two healthy parts. If ever, the anastomosis can not be performed due to too much inflammation, the surgeon will decide to do a transient “colostomy”. The “colostomy” consists of suturing the colon to the skin and collecting the excrement via a pocket. After several weeks, continuity will be restored during a new surgical procedure to allow the natural evacuation of stool.
If the cancer ever reaches the ganglion areas or the peritoneum, the surgeon will have to remove the diseased areas.

What is surgical treatment of rectal cancer?

Rectal surgery is a more delicate procedure than the colon because the rectum is more difficult to access. Depending on the location of the tumor, several types of interventions are possible.
• If the tumor is located in the upper part of the rectum , the surgeon will remove the sigmoid colon and the first half of the rectum.
• But when the cancer is in the lower two-thirds of the rectum, it is a ”  total proctectomy Which will be performed, that is to say, excision of the entire rectum and the mesorectum. The mesorectum is the fibrous and muscular tissues around the rectum that contain the ganglia and vessels. The anus will be preserved as much as possible to maintain the continuity of the digestive tract.
• If the tumor is too low or too infiltrating , the anus can not be preserved, this is called ”  abdominoperineal resection  “. In this case, there will be irreversible rupture of continuity, which will require the installation of a ”  permanent colostomy  ” to evacuate the stool.

What is radiotherapy?

Radiation therapy is a treatment that destroys cancer cells by irradiating the tumor. It is indicated when the cancer of the rectum has spread to neighboring organs .
There are two techniques to irradiate the tumor, either by sending rays through the skin, it is the ”  external radiotherapy  “, or by injection inside the rectum of an implant diffusing radioactive substances, it is internal radiotherapy, also called ”  brachytherapy  “.
This treatment can be proposed as a treatment in addition to surgery, it is then a ”  adjuvant radiotherapy “. Doses and indications for radiation therapy vary according to the patient and the stage of the cancer. The combination of external and internal radiotherapy allows synergistic efficacy when the tumors are large.
Despite the precautions taken by the medical team responsible for radiotherapy for not irradiating healthy tissue, there are often side effects that the treated person must know. The side effects reported most often are inflammations of the bladder or rectum as well as for women vaginal dryness.

What are the principles of chemotherapy?

Treatment with chemotherapy is considered when the cancer is at an advanced stage of infiltration , but also in palliative care to reduce pain.
Chemotherapy is usually a treatment injected into the blood to reach and destroy cancer cells throughout the body, including those that could have come off the primary tumor.
The reference drug is 5-fluorouracil (or 5-FU) . Several medications can be given at the same time is what is called an association or ”  multidrug therapy  “.
The disadvantage of these drugs is their side effectsespecially on hair loss, nausea and frequent diarrhea. In fact, chemotherapy attacks cancer cells but also cells that multiply rapidly and this is the case of the cells of the digestive mucosa and those of the hair.

What are the principles of targeted therapy?

Targeted therapies are commonly used treatments in addition to chemotherapy in advanced colorectal cancers .
Their principle is to target the physiological mechanisms that allow the tumor to proliferate. For example, there are drugs that will somehow asphyxiate the tumor by stopping the formation of new blood vessels or that will prevent it from growing by suppressing growth factors.
The advantage of these therapies is that they are specific to the tumor cells and will therefore limit the destruction of healthy cells in the body as can chemotherapy.

You might want to learn more about Chinese Doctors in Hong Kong that deal with colon cancer checks and treatments.