Surgery is the most effective treatment option as far as colon cancer is concerned. In colon cancer removing the tumour or the tumour affected portion of the colon and the nearby lymph nodes will be the best treatment option.
- Polypectomy: In polypectomy, the polyps are removed from its root. This is done by passing an electric current through the wall of the colon and cutting the polyp with the help of colonoscope.
- Local excision: In this surgery method, polyps are removed using tools through the colonoscope. The polyps inside the colon are removed along with some healthy cells of the colon wall.
- Colectomy: In colectomy, a part of the colon or the whole colon is removed along with nearby lymph nodes. If the cancer is large, a partial colectomy can be performed.
- In partial colectomy, cancer tissues and the small part of the healthy tissue around the affected area are removed. The doctor then sews up the healthy parts of the colon together. In total colectomy, the entire colon is removed.
Generally, colectomy is done in 2 ways:
- Open colectomy- Where the abdomen is opened through a long cut and surgery is done through it.
- Laparoscopic colectomy- The surgery is done through multiple small incisions using special tools.
Since the laparoscopic incision is smaller the time to heal is also less. But the complication to use the tools and expertise required makes it a difficult method.
In case the colon cannot be sewed up after the colectomy, then an opening called stoma is made on the outside of the colon, for the stool to pass through. A bag is placed on the stoma in a colostomy.
Further, if the lower colon is completely removed, then the colostomy bag will be permanent. Otherwise, the bag can be removed after the colon is healed.
- Radiofrequency ablation: Here, a thin probe is passed to the tumour affected area and high energy radio waves are used to heat up the probe. The heated probe is guided using the CT scan or the ultrasound and the tumour is destroyed.
- Cryosurgery: Cryosurgery is performed by freezing the tumour cells and killing them. A metal probe is guided through the skin to the tumour and cold gasses are passed through the probe. This treatment is also called cryotherapy.
- Chemotherapy, often referred to as chemo is a treatment method that is used in colon cancer. Drugs are used in order to kill the cancerous cells or stop them from multiplying. Generally, chemotherapy is done in 2 ways. Drugs are introduced to the body orally or injected through veins or muscles.
- Chemotherapy is done in cycles. These cycles of treatment are followed by a period of time given for the body to recover from the pre-chemo cycles.
- Ways in which chemotherapy is administrated in colon cancer:
- Systematic Chemotherapy: Drugs are put directly into the blood intravenously or taken orally. Here the drug is circulated throughout the body, which will help in reducing the risk of colon cancer spreading to other organs.
- Regional Chemotherapy: Drugs are introduced directly through the artery that connects with the colon. This solely focuses on the colon and the nearby area rather than circulating the drug all over the body. This will reduce the side effects of the treatment on a big scale.
- Chemotherapy can be given at a different period of time during the treatment.
- Neoadjuvant chemo: In some cases, chemotherapy is given before surgery. Here chemo is given to shrink the cancerous cells which will make it easier to remove the tumour through surgery.
- Adjuvant Chemo: Even after surgery, there is a chance that there are some cancerous cells left behind. It may be because the cancer cells are very small or couldn’t be differentiated. So, after surgery, there lies a chance that cancer can recur. During this scenario, chemotherapy is used to kill any cancer cells that are left behind.
In the case when cancer has spread to other organs, chemotherapy is given in order to shrink cancer. It will help in reducing the problems caused by cancer and extend the lifespan.
High-energy rays are targeted to the cancerous cells to destroy them. Radiation therapy is often simultaneously used with chemotherapy in colon cancer.
Radiation therapy in cancer is sometimes given before surgery to help the tumor shrink. It will make it easy to remove the tumour surgically.
Sometimes after surgery radiation is used in order to reduce the chances of recurrence. It helps to kill any cancer cells that may have been missed during surgery. During surgery also radiation therapy is given which is called Intraoperative radiation therapy(IORT)
In some cases, only chemo and radiation therapy is used to treat cancer due to the health issue of the patient.
In cases where cancer has advanced radiation therapy is used to ease the symptoms of cancer.
External beam radiation therapy (EBRT): In colon cancer, EBRT is used mostly. This type of radiation therapy is focused from outside the body.
When the chemotherapy doesn’t work, targeted therapy is used. In targeted therapy, only the cancerous cells get affected. Rest of the cells are unharmed.
Monoclonal antibodies Antibodies that are made from immune system cells are called Monoclonal antibodies. These antibodies target only the cancerous cells or block them from growing.
- Vascular endothelial growth factor (VEGF) targeting: VEGF is a protein that helps the new blood vessels to form in the tumour region that will give nutrition to the cancerous cells. By targeting VEGF, they block the nutrition flow to the cancerous cells which will keep them from growing.
- Epidermal growth factor receptor (EGFR) targeting: EGFR is a type of protein that helps the cancer cells to grow. By targeting EGFR, the cancer is restricted from growing.
In this treatment, the patient’s immune system is boosted up to defend against cancer. By boosting the immune system, it recognizes and destroys the cancer cells. Immunotherapy is a treatment option given to people who have advanced colon cancer.
Some drugs that are called checkpoint inhibitors are used in immunotherapy. These drugs boost the immune system and attack cancer cells efficiently. Generally, this treatment is done in people whose cancer is still growing after chemotherapy, people whose cancer cannot be removed through surgery and for people whose cancer had spread to other organs.
- PD-1 inhibitors: PD-1 is a type of protein on the T cells that helps the immune system to check the immune response. These inhibitors help the T cells in recognizing the cancer cells and attacking them. PD-1 inhibitors are generally given intravenous every 2 to 3 weeks.
- CLTA-4 inhibitor: CLTA-4 inhibitor also boosts up the immune response. It blocks another protein on T-cell that helps the immune system to suppress cancer.
Stage wise colon cancer treatment in India
The treatment for colon cancer is decided or given depending on the stage of cancer. In colon cancer, mostly the cancer is treated with surgery unless it has spread to other organs. Sometimes chemotherapy is also used after surgery to reduce the risk of recurrence.
Stage 0 Colon cancer:
Stage 0 cancer is when cancer has not spread beyond the inner lining of the colon. Mostly only surgery is needed to take out these cancerous cells. The polyp or the affected cells can be taken out through local excision (colonoscope). A partial colectomy is sometimes used in case the tumour is too big to be removed by the colonoscope.
Stage 1 Colon cancer:
Here, cancer has grown deep inside the layers of the colon wall. But it has not spread outside the colon wall or the nearby lymph nodes.
If the cancer cells are part of the polyp, surgical removal of these polyps may be the only treatment needed. These polyps will be removed during colonoscopy with no cancer cells at the edges of the removed piece. Multiple surgeries may be done depending on the grade. Incase if the cancer is not present in the polyp, partial colectomy is done.
Stage 2 Colon cancer:
Stage 2 cancer has grown through the wall of the colon and to the nearby tissues. But not to the lymph nodes. Stage 2 cancer is divided into stage 2 A, Stage 2 B, and stage 2 C.
- Stage 2 A is when cancer has spread to the outermost layer of the colon.
- Stage 2 B is when cancer has spread even further. From the outermost layer of the colon, it has spread to tissues that attach to other organs in the stomach.
- Stage 2 C is when cancer has spread even further from the outermost layer of the colon to the nearby organs.
A partial colectomy is done and the affected part of the colon is removed along with the nearby lymph nodes. Sometime adjuvant chemotherapy is also suggested in order to reduce the risk of cancer coming back.
Stage 3 Colon Cancer
In stage 3, colon cancer has spread to the nearby lymph nodes. But it hasn’t spread to other parts of the body. In this stage partial colectomy with adjuvant chemotherapy is the general treatment suggested. Considering the health of patient radiation therapy is also used.
Stage 3 colon cancer is classified into A, B, C.
- Stage 3 A, colon cancer has spread from the innermost layer of the colon to the nearby tissues or further into the muscle layers. It may have also spread to 2 or 3 nearby lymph nodes. Or cancer has affected more than 3 nearby lymph nodes. (around 4 to 6)
- Stage 3 B colon cancer is when cancer has spread through the muscle layer of the colon to the outermost layer of the colon. Or it has spread to the nearby tissues that line the organs in the stomach. Cancer may have affected 1 or 3 nearby lymph nodes or tissues near them. Or it has spread to 4 to 6 or 7 or more nearby lymph nodes.
- Stage 3 C cancer in the colon has spread through the outer most layer of the colon wall to the tissue lines of the nearby organs in the stomach. Cancer has also spread to the nearby 4 to 6 lymph nodes or 7 or more lymph nodes. Further, cancer may have spread from the outermost layer of the colon to the nearby organs or lymph nodes near the organ.
Stage 4 Colon Cancer:
In stage 4, colon cancer has spread to other parts of the body. It has spread through the blood and the lymph nodes. Most often it spread to liver, lungs, brain etc. For stage 4 cancer patients’ surgery is not preferred. But in cases where cancer has spread only to a small region and it can be surgically removed, then surgery is done. In these cases, chemo is given before or after the surgery.
If surgery cannot be done because cancer has spread extensively then chemotherapy is given as the main treatment option. Mostly the patients with stage 4 colon cancer are treated with chemo and targeted therapy. Another option for them is immunotherapy. For advanced level of colon cancer, radiation therapy is also given to shrink the tumour.
Further, stage 4 colon cancer is also divided into A, B, C.
- Stage 4 A colon cancer is when cancer has spread to one area or organ that is not near the colon. Like liver, lungs, ovary or even distant lymph nodes.
- Stage 4 B colon cancer is when cancer has spread to more than one area or organ that is not near the colon.
- Stage 4 C is when cancer has spread to the tissue that lines the wall of the stomach and may have spread to the other areas or organs.
Recurrent Colon Cancer
Recurrent colon cancer is a type of cancer which recurs after the treatment. This recurrence of colon cancer may be local or it may appear in distant organs. If the recurrence is in the same organ, it is called local recurrence.
Local recurrence is treated with surgery and chemotherapy. In some cases where the tumour is difficult to remove, chemo is given before the surgery to shrink the tumour. After shrinking the tumour, surgery is performed to make sure that cancer doesn’t recur.
If cancer recurs in a distant organ, then surgery is an option.
Chemo is given to shrink the tumour when surgery is not enough. Once the tumour is shrunk, surgery is performed to remove the tumour. There are treatments similar to stage 4 treatments given for such recurrence of cancer. Usually, the treatment options are relevant to the cancer treatment which you had before the recurrence and also factors in the duration of that earlier treatment.
Risk Factors For Developing Colon Cancer
Different cancers have different risk factors. There are some common risk factors as well. Having risk factors doesn’t mean that you will get cancer and having no risk factor doesn’t mean that you will never have cancer. Risk factors only mean that you have a higher chance of getting cancer.
You have a high risk of colon cancer if you have/are:
- Overweight or Obese.
- Physically Inactive.
- Family history of colon cancer increases your chances of getting cancer.
- If you had colon cancer or polyps, the chances of getting colon cancer again are higher.
- Being an alcoholic makes you viable to colon cancer.
- Smoking cigarettes.
- Eating too much red meat or oily food increases the risk of colon cancer.
- Ethnic and racial background.
- Having type 2 diabetes.
Symptoms of Colon Cancer:
Symptoms are the signals which the body gives you when there is something going wrong. Having these symptoms doesn’t mean that you are having cancer. It may be due to other reasons also. But if you have any of these symptoms, you should be cautious about it.
The symptoms of colon cancer are these:
- Diarrhea, constipation or narrowing of the stool which lasts more than a few days.
- Rectal bleeding.
- Dark stool or bleeding.
- Sudden weight loss.
- Tiredness and fatigue
- Stomach Pain
- Gas problems and fullness in the stomach.
Side effects of Colon Cancer treatment
Colon cancer treatment comes with some side effects. They happen because the treatment damages the healthy cells also. It depends on the extent of cancer and the treatment done. The side effects vary from person to person and it pretty much changes from one cycle to another. A patient who is going for the colon cancer treatment or who is undergoing the treatment should know what side effects he/she should expect and be mentally and physically prepared for it.
So here is the list of the possible side effects of colon cancer treatments.
- Blood clots in the leg
- Hair loss
- Mouth Sores
- Loss of appetite
- Hand-foot syndrome
- Allergic or sensitivity reaction
- Skin irritation
- Problems with wound healing
- Blood in the stool
- Stool leakage
- Bladder irritation
- Sexual problems
- Stiffening, scarring in the treated area
- High blood pressure
In rare cases, the side effects may be so severe that they can be life-threatening. These side effects might include problems with the kidney, liver, heart, etc. So during treatment for colon cancer, any problem that you face should preferably be discussed with your oncologist regularly.