• Colon resection with colostomy: If the doctor cannot sew the two ends of the colon together, a stoma (hole) is made on the outside of the body to allow waste to pass through. This procedure is called a colostomy. A waste collection bag is placed around the stoma. Sometimes a colostomy is needed only until the lower part of the colon has healed, and then it can be cancelled. However, if the doctor needs to remove the entire lower colon, the colostomy may be permanent.

​

After the doctor removes any tumors that can be seen during surgery, some patients may be given chemotherapy or radiation therapy after surgery to kill any remaining cancer cells. Treatment given after surgery to reduce the risk of cancer coming back is called adjuvant therapy.

 

2. Radiofrequency ablation

​

RF ablationis the use of a special probe with tiny electrodes that kill cancer cells. Sometimes the probe is inserted directly through the skin and only local anesthesia is needed. In other cases, the probe is inserted through an incision in the abdomen. This is done in a hospital under general anesthesia.

 

3. Cryosurgery

​

Cryosurgeryis a treatment that uses an instrument to freeze and destroy abnormal tissue. This type of treatment is also called cryotherapy.

 

4. Chemotherapy

​

Chemotherapyis a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is injected directly into the cerebrospinal fluid, organ, or body cavity, such as the abdominal cavity, the drugs primarily target cancer cells in those areas (regional chemotherapy).

​

Chemoembolization from the hepatic artery can be used to treat cancer that has spread to the liver. This includes blocking the hepatic artery (the main artery that supplies blood to the liver) and injecting anticancer drugs between the blockage and the liver. The liver arteries then deliver the drugs to the liver. Only a small amount of the drug reaches other parts of the body. The blockage can be temporary or permanent, depending on what is being used to block the artery. The liver continues to receive blood from the hepatic portal vein, which carries blood from the stomach and intestines.

How chemotherapy is given depends on the type and stage of cancer treatment.

​

5. Radiation therapy

​

Radiation therapyis a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or prevent them from growing. There are two types of radiation therapy:

​

• External Beam Therapy uses a device outside the body to direct radiation to an area of the body affected by cancer.

​

• Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires or catheters that are injected directly into or near the tumor.

 

How radiation therapy is given depends on the type and stage of cancer treatment. External beam radiation therapy is used as a palliative therapy to relieve symptoms and improve quality of life.

​

6. Targeted therapy

​

Targeted Therapy  is a type of treatment that uses drugs or other substances to target and target specific cancer cells. Targeted therapy usually causes less damage to normal cells than chemotherapy or radiation therapy.

​

Types of targeted therapies used in the treatment of colon cancer include the following:

​

• Monoclonal antibodies : Monoclonal antibodies are immune system proteins created in a laboratory to treat many diseases, including cancer. As a treatment for cancer, these antibodies can attach to a specific target on cancer cells or other cells that can promote cancer cell growth. The antibodies are then able to kill the cancer cells, block their growth, or stop them from spreading. Monoclonal antibodies are given by infusion. They can be used alone or to carry drugs, toxins, or radioactive materials directly to cancer cells.

 

  Species:​

There are different types of monoclonal antibody therapy:

 

• Vascular endothelial growth factor (VEGF) inhibitor therapy: Cancer cells produce a substance called VEGF, which causes new blood vessels to form (angiogenesis) and promotes cancer growth. VEGF inhibitors block VEGF and prevent the formation of new blood vessels. This can kill cancer cells because they need new blood vessels to grow. Bevacizumab and ramucirumab are VEGF inhibitors and angiogenesis inhibitors.

​

• Epidermal growth factor receptor (EGFR) inhibitor therapy: EGFRs are proteins found on the surface of certain cells, including cancer cells. Epidermal growth factor attaches to EGFR on the cell surface and causes cells to grow and divide. EGFR inhibitors block the receptor and prevent epidermal growth factor from attaching to the cancer cell. This stops the growth and division of the cancer cell. Cetuximab and panitumumab are EGFR inhibitors.

​

• Angiogenesis Inhibitors: Angiogenesis inhibitors stop the growth of new blood vessels needed for tumor growth.

​

• Ziv-aflibercept is a vascular endothelial growth factor decoy that blocks an enzyme needed for the growth of new blood vessels in tumors.

​

• Regorafenib is used to treat colorectal cancer that has spread to other parts of the body and has not improved with other treatments. It blocks the action of certain proteins, including vascular endothelial growth factor. This can help prevent cancer cells from growing and killing them. It can also prevent the growth of new blood vessels needed for tumor growth.

​

7. Immunotherapy

​

• Immunotherapyis a treatment that uses the patient's immune system to fight cancer. Substances produced by the body or produced in a laboratory are used to enhance, direct, or restore the body's natural defenses against cancer. This cancer treatment is a type of biological therapy.

​

• Immune checkpoint inhibitor therapy is a type of immunotherapy:

• ​

• PD-1 and PD-L1 inhibitor therapy: PD-1 is a protein on the surface of T cells that helps control the body's immune responses. PD-L1 is a protein found on some types of cancer cells. When PD-1 attaches to PD-L1, it stops the T cell from killing the cancer cell. PD-1 and PD-L1 inhibitors prevent the PD-1 and PD-L1 proteins from attaching to each other. This allows T cells to kill cancer cells. Pembrolizumab is one of the PD-1 inhibitors.

​

1.6. Treatment options by stage

 

Stage 0 treatment (carcinoma in situ)

​

Treatment for stage 0 (carcinoma in situ) may include the following types of surgery:

​

• Local excision or simple polypectomy.

• Resection and anastomosis. This is done when the tumor is too large to be removed by local excision.

​

Treatment of colon cancer stage I

​

Treatment for stage I colon cancer usually includes the following:

​

• Resection and anastomosis .

​

Treatment of colon cancer stage II

​

Treatment for stage II colon cancer may include the following:

​

• Resection and anastomosis.

​

Treatment for stage III colon cancer

​

Treatment for stage III colon cancer may include the following:

​

• Resection and anastomosis followed by chemotherapy.

• Clinical trials of new chemotherapy regimens after surgery.

​

Treatment of stage IV and recurrent colon cancer

​

Treatment for stage IV and recurrent colon cancer may include the following:

​

• Local excision for tumors that recur.

• Resection with or without anastomosis.

• Surgery to remove parts of other organs such as the liver, lungs, and ovaries where the cancer may have recurred or spread. Treatment for cancer that has spread to the liver may also include the following:

  • Chemotherapy is given before surgery to shrink the tumor, after surgery, or both before and after.

  • Radiofrequency ablation or cryosurgery for patients who cannot be operated on.

  • Chemoembolization from the hepatic artery.

• For some patients, radiation therapy or chemotherapy may be offered as palliative therapy to relieve symptoms and improve quality of life.

• Chemotherapy and/or targeted therapy with monoclonal antibodies or an angiogenesis inhibitor.

• Immunotherapy.

• Clinical trials of chemotherapy and/or targeted therapy.

​

2. What is rectal cancer?

​

Rectal canceris a disease in which malignant (cancer) cells form in the tissues of the rectum.

​

The rectum is part of the body's digestive system. The digestive system obtains nutrients (vitamins, minerals, carbohydrates, fats, proteins, and water) from foods and helps eliminate waste from the body. The digestive system consists of the esophagus, stomach, small intestine, and large intestine. The large intestines (large intestine) are the first part of the large intestine and are about 5 feet long. Together, the rectum and anal canal make up the last part of the large intestine and are 6 to 8 inches long. The anal canal ends at the anus (the exit of the large intestine to the outside).

​

2.1. Factors risk of colorectal cancer

​

Anything that increases the likelihood of a disease is called a risk factor. Having a risk factor does not mean you will get cancer; the absence of risk factors does not mean that you will not get cancer. Talk to your doctor if you think you are at risk of developing colorectal cancer.

​

Risk factors for colorectal cancer include the following:

​

• Having a family history of colon or rectal cancer in the first degree of relationship (parents, sibling, or child).

• Having a personal history of colon, rectal, or ovarian cancer.

• Having a personal history of high-risk adenomas (colorectal polyps 1 centimeter or larger, or cells that look abnormal under a microscope).

• Having inherited changes in certain genes that increase the risk of familial adenomatous polyposis (FAP) or Lynch syndrome (hereditary non-polyposis colorectal cancer).

• A history of chronic ulcerative colitis or Crohn's disease for 8 years or more.

• Drinking three or more alcoholic drinks per day.

• Smoking cigarettes.

• Be African American.

• Be obese.

 

Old age is a major risk factor for most types of cancer. The chance of getting cancer increases with age.

​

2.2. Signs of colorectal cancer

 

Signs of rectal cancer include changes in the bowel or blood in the stool.

These and other signs and symptoms may be caused by colon cancer or other conditions. Check with your doctor if you have any of the following:

​

• Blood (bright red or very dark) in stool.

• Change in bowel habits.

  • Diarrhea.

  • Constipation.

  • Sensation that the bowels are not emptying completely.

  • The stool is narrower or of a different shape than usual.

• General abdominal discomfort (frequent gas pains, bloating, feeling of fullness or cramps).

• Change in appetite.

• Weight loss for unknown reason.

• Feeling very tired.

​

2.3. Tests for diagnostics rectal cancer

​

Tests used to diagnose rectal cancer include the following:

​

• Medical examination and medical history : examining the body to check for general signs of health, including checking for signs of disease such as lumps or anything else that seems unusual. An anamnesis of the patient's health habits as well as past illnesses and treatments will also be taken.

​

• Digital Rectal Examination (DRE) : examination of the rectum. The doctor or nurse inserts a lubricated, gloved finger into the lower rectum to feel for lumps or anything else that seems unusual. In women, the vagina can also be examined.

​

• Colonoscopy :a procedure for examining the rectum and colon for polyps (small pieces of raised tissue), abnormal areas, or cancer. The colonoscope is a thin, tube-like instrument with light and viewing lenses. It may also have a tool to remove polyps or tissue samples that are checked under a microscope for signs of cancer.

​

• Biopsy : removal of cells or tissue so that they can be viewed under a microscope for signs of cancer. Tumor tissue that is removed during a biopsy can be tested to see if the patient has a gene mutation that causes HNPCC. This can help plan treatment. The following tests may be used:

​

1. Reverse transcription polymerase chain reaction (RT-PCR) test : A laboratory test that measures the amount of a genetic substance called mRNA made by a particular gene. An enzyme called reverse transcriptase is used to convert a specific piece of RNA into a matching piece of DNA that can be amplified (done in large quantities) by another enzyme called DNA polymerase. Amplified DNA copies help determine if a particular mRNA is being created by a genome. RT-PCR can be used to check for the activation of certain genes that may indicate the presence of cancer cells. This test can be used to look for specific changes in a gene or chromosome that can help diagnose cancer.

2. Immunohistochemistry:a laboratory test that uses antibodies to test for specific antigens (markers) in a patient's tissue sample. The antibodies are usually associated with an enzyme or fluorescent dye. After the antibodies bind to a specific antigen in the tissue sample, the enzyme or dye is activated and the antigen can be seen under a microscope. This type of test is used to diagnose cancer and helps distinguish one type of cancer from another.

3. Carcinoembryonic antigen (CEA) analysis:a test that measures the level of CEA in the blood. CEA enters the bloodstream from both cancerous and normal cells. If its amount exceeds normal, it may be a sign of rectal cancer or other diseases.

​

After rectal cancer has been diagnosed, tests are done to find out if the cancer cells have spread in the rectum or to other parts of the body.

​

The process used to determine if cancer has spread to the rectum or to other parts of the body is called staging. The information gathered during the staging process determines the stage of the disease. It is important to know the stage in order to plan treatment.

​

The following tests and procedures may be used in the preparation process:

​

• Chest x-ray : X-ray of the organs and bones inside the chest. An X-ray is a type of energy beam that can pass through the body onto film, creating an image of areas within the body.

​

• Colonoscopy : a procedure for examining the rectum and colon for polyps (small pieces of raised tissue). abnormal areas or cancer. The colonoscope is a thin, tube-like instrument with light and viewing lenses. It may also have a tool to remove polyps or tissue samples that are checked under a microscope for signs of cancer.

​

• CT (computed tomography) : A procedure that takes a series of detailed pictures of areas inside the body, such as the abdomen, pelvis, or chest, taken from different angles. The pictures were taken by a computer connected to an x-ray machine. The dye may be injected into a vein or swallowed to make organs and tissues more visible. This procedure is also called computed tomography, computed tomography, or computed axial tomography.

​

• MRI (magnetic resonance imaging) : A procedure that uses a magnet, radio waves and a computer to create a series of detailed pictures of areas inside the body. This procedure is also called nuclear magnetic resonance imaging (NMRI).

​

• PET scan (positron emission tomography) : procedure for searching for malignant tumor cells in the body. A small amount of radioactive glucose (sugar) is injected into a vein. The PET scanner rotates around the body and takes a picture of where glucose is being used in the body. The cells of malignant tumors appear brighter because they are more active and consume more glucose than normal cells.

​

• Endorectal Ultrasound : A procedure used to examine the rectum and nearby organs. An ultrasound transducer (transducer) is inserted into the rectum and is used to bounce high energy sound waves (ultrasound) from internal tissues or organs and make echoes. The echo forms a picture of body tissues called a sonogram. A doctor can identify a tumor by looking at a sonogram. This procedure is also called transrectal ultrasound.

​

2.4. Types of treatment for patients with rectal cancer

 

A variety of treatments are available for patients with rectal cancer. Some treatments are standard (currently used) and some are in clinical trials. A clinical trial of a treatment is a scientific study designed to help improve existing treatments or provide information about new treatments for patients with cancer. When clinical trials show that a new treatment is better than the standard treatment, the new treatment may become the standard treatment. Patients may wish to participate in a clinical trial. Some clinical trials are only open to patients who have not yet started treatment.

​

Six types of standard treatment are used:

​

1. Operation

​

Surgery - the most common treatment for rectal cancer at all stages. The cancer is removed with one of the following types of surgery:

​

• Polypectomy : If cancer is found in a polyp (a small piece of swollen tissue), the polyp is often removed during a colonoscopy.

​

• Local excision : If the cancer is found on the inside of the rectum and has not spread to the rectal wall, the cancer and a small amount of surrounding healthy tissue are removed.

​

• Resection : if the cancer has spread to the rectal wall, the area of the rectum with cancer and nearby healthy tissue is removed. Sometimes the tissue between the rectum and the abdominal wall is also removed. The lymph nodes near the rectum are removed and checked under a microscope for signs of cancer.

​

• Radiofrequency ablation:using a special probe with tiny electrodes that kill cancer cells. Sometimes the probe is inserted directly through the skin and only local anesthesia is needed. In other cases, the probe is inserted through an incision in the abdomen. This is done in a hospital under general anesthesia.

​

• Cryosurgery :a treatment that uses an instrument to freeze and destroy abnormal tissue. This type of treatment is also called cryotherapy.

​

• Pelvic exenteration : If the cancer has spread to other organs near the rectum, the lower colon, rectum, and bladder are removed. In women, the cervix, vagina, ovaries, and nearby lymph nodes may be removed. In men, the prostate may be removed. Artificial openings (stoma) are designed to drain urine and stool from the body into a collection bag.

​

After cancer removal surgeon :

​

• make an anastomosis (sew healthy parts of the rectum, sew up the rest 

or

• make a stoma (hole) from the rectum to the outside of the body to allow waste to pass through. This procedure is done if the cancer is too close to the anus and is called a colostomy. A waste collection bag is placed around the stoma. Sometimes a colostomy is needed only until the rectum has healed, and then it can be cancelled. However, if the entire rectum is removed, the colostomy may be permanent.

​

Radiation therapy and/or chemotherapy may be given before surgery to shrink the tumor, make it easier to remove the cancer, and help with bowel control after surgery. Treatment before surgery is called neoadjuvant therapy. After all cancer that can be seen during surgery is removed, some patients may be given radiation therapy and/or chemotherapy after surgery to kill any remaining cancer cells. Treatment given after surgery to reduce the risk of cancer coming back is called adjuvant therapy.

​

2. Radiation therapy

​

Radiation therapyis a cancer treatment that uses high-energy x-rays or other types of radiation to kill cancer cells or prevent them from growing. There are two types of radiation therapy:

​

• External Beam Therapyuses a device located outside the body to target cancer with radiation.

​

• Internal radiation therapyuses a radioactive substance sealed in needles, seeds, wires, or catheters that are inserted directly into or near the tumor.

​

How radiation therapy is given depends on the type and stage of cancer treatment. External beam radiation therapy is used to treat rectal cancer.

​

Short-term preoperative radiation therapy is used for some types of rectal cancer. This treatment uses smaller and lower doses of radiation than standard treatment, followed by surgery a few days after the last dose.

​

3. Chemotherapy

​

Chemotherapyis a cancer treatment that uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When chemotherapy is given directly to the cerebrospinal fluid, an organ, or a body cavity such as the abdomen, the drugs primarily target cancer cells in those areas (regional chemotherapy).

​

Chemoembolization of the hepatic artery is a type of regional chemotherapy that can be used to treat cancer that has spread to the liver. This is done by blocking the hepatic artery (the main artery that supplies blood to the liver) and injecting anticancer drugs between the blockage and the liver. The liver arteries then carry the drugs to the liver. Only a small amount of the drug reaches other parts of the body. The blockage can be temporary or permanent, depending on what is being used to block the artery. The liver continues to receive blood from the hepatic portal vein, which carries blood from the stomach and intestines.

​

How chemotherapy is given depends on the type and stage of cancer treatment.

​

4. Active Surveillance

​

Active surveillance closely monitors the patient's condition without giving any treatment unless there is a change in test results. It is used to detect early signs of deterioration. In active surveillance, patients undergo certain examinations and tests to check if the cancer is growing. When the cancer begins to grow, treatment is given to cure the cancer. Tests include the following:

• Digital rectal examination.

• MRI.

• Endoscopy.

• Sigmoidoscopy.

• CT scan .

• Carcinoembryonic antigen (CEA) analysis

 

5. Targeted Therapy

​

Targeted Therapyis a type of treatment that uses drugs or other substances to target and attack specific cancer cells without harming normal cells.

​

Types of targeted therapies used in the treatment of rectal cancer include the following:

​

• Monoclonal antibodies: Monoclonal antibody therapy is a type of targeted therapy that is used to treat rectal cancer. Monoclonal antibody therapy uses antibodies made in a laboratory from a single cell type of the immune system. These antibodies can identify substances on cancer cells or normal substances that can promote cancer cell growth. Antibodies attach to substances and kill cancer cells, block their growth or stop them from spreading. Monoclonal antibodies are given by infusion. They can be used alone or to carry drugs, toxins, or radioactive materials directly to cancer cells.

• ​

There are different types of monoclonal antibody therapy:

​

• Vascular endothelial growth factor (VEGF) inhibitor therapy: Cancer cells produce a substance called VEGF, which causes new blood vessels to form (angiogenesis) and promotes cancer growth. VEGF inhibitors block VEGF and prevent the formation of new blood vessels. This can kill cancer cells because they need new blood vessels to grow. Bevacizumab and ramucirumab are VEGF inhibitors and angiogenesis inhibitors.

• Epidermal growth factor receptor (EGFR) inhibitor therapy: EGFRs are proteins found on the surface of certain cells, including cancer cells. Epidermal growth factor attaches to EGFR on the cell surface and causes cells to grow and divide. EGFR inhibitors block the receptor and prevent epidermal growth factor from attaching to the cancer cell. This stops the growth and division of the cancer cell. Cetuximab and panitumumab are EGFR inhibitors.

• Angiogenesis Inhibitors: Angiogenesis inhibitors stop the growth of new blood vessels needed for tumor growth.

• Ziv-aflibercept is a vascular endothelial growth factor decoy that blocks an enzyme needed for the growth of new blood vessels in tumors.

• Regorafenib is used to treat colorectal cancer that has spread to other parts of the body and has not improved with other treatments. It blocks the action of certain proteins, including vascular endothelial growth factor. This can help prevent cancer cells from growing and killing them. It can also prevent the growth of new blood vessels needed for tumor growth.

​

6. Immunotherapy

​

Immunotherapyis a treatment that uses the patient's immune system to fight cancer. Substances produced by the body or produced in a laboratory are used to enhance, direct, or restore the body's natural defenses against cancer. This type of cancer treatment is also called biotherapy or biological therapy.

​

Immune checkpoint inhibitor therapy is a type of immunotherapy:

​

• Immune checkpoint inhibitor therapy: PD-1 is a protein on the surface of T cells that helps control the body's immune responses. When PD-1 attaches to another protein called PDL-1 on a cancer cell, it stops the T cell from killing it. PD-1 inhibitors attach to PDL-1 and allow T cells to kill cancer cells. Pembrolizumab is one of the immune checkpoint inhibitors.

​

3. Factors affecting prognosis (chance of recovery) and treatment options

​

The prognosis (chance of recovery) and treatment options depend on the following conditions:

​

• The stage of the cancer (whether it affects the internal lining of the rectum only, involves the entire rectum, or has spread to lymph nodes, nearby organs, or to other locations in the body).

• Whether the tumor has spread to or through the intestinal wall.

• Where cancer is found in the rectum.

• Whether the intestines are clogged or there is a hole in it.

• Is it possible to remove the entire tumor surgically.

• The general health of the patient.

• Whether the cancer was just diagnosed or recurred (came back).