What is Colorectal Cancer?
Colorectal cancer is a kind of cancer that affects the digestive system.
A colon cancer starts in the colon, whereas a rectal cancer starts in the rectum. Colorectal cancer refers to cancer that affects one or both of these organs. The majority of colorectal cancers develop from adenomatous (precancerous) polyps over time, though this is not true in every case. Following a series of mutations (abnormalities) in their cellular DNA, polyps (growths) can change. A family history of colon or rectal cancer, diet, alcohol consumption, smoking, and inflammatory bowel disease are just a few of the risk factors for colorectal cancer.
What parts of the body are affected by colorectal cancer?
It's helpful to know what parts of the body are affected by colorectal cancer and how they function to comprehend the disease.
The colon connects the small intestine to the rectum and is approximately 5- to 6-foot long. The colon, along with the rectum, makes up the large intestine, which transports and digests food across your body and down to the rectum, where it is expelled as stool. The colon is made up of several parts, such as:
Undigested food starts its journey through the colon in this section. Undigested food moves upwards in this section, where fluid is more efficiently reabsorbed.
The food is transported from one side of the body to the other by the transverse colon, which moves across the body (right to left).
The food then travels down the descending colon, which is usually on the left side, after crossing the top through the transverse colon.
The last stop before the rectum is the sigmoid colon, which is shaped like a "S."
The rectum is a muscle in the lower abdomen.
The rectum connects the colon to the anus and is a 5- to 6-inch chamber. The rectum's job is to act as a storage unit for the stool until it is defecated (evacuated).
Types of colorectal cancer
Most colorectal cancers are adenocarcinomas. These cancers start in cells that make mucus to lubricate the inside of the colon and rectum. When doctors talk about colorectal cancer, they're almost always talking about this type. Some sub-types of adenocarcinoma, such as signet ring and mucinous, may have a worse prognosis (outlook) than other subtypes of adenocarcinoma.
Other, much less common types of tumors can also start in the colon and rectum. These include:
- Carcinoid tumors. These start from special hormone-making cells in the intestine.
- Gastrointestinal stromal tumors (GISTs)start from special cells in the wall of the colon called the interstitial cells of Cajal. Some are benign (not cancer). These tumors can be found anywhere in the digestive tract, but are not common in the colon.
- Lymphomasare cancers of immune system cells. They mostly start in lymph nodes, but they can also start in the colon, rectum, or other organs..
- Sarcomascan start in blood vessels, muscle layers, or other connective tissues in the wall of the colon and rectum. Sarcomas of the colon or rectum are rare.
How does colorectal cancer start?
Polyps in the colon or rectum
Most colorectal cancers start as a growth on the inner lining of the colon or rectum. These growths are called polyps.
Some types of polyps can change into cancer over time (usually many years), but not all polyps become cancer. The chance of a polyp turning into cancer depends on the type of polyp it is. There are different types of polyps.
- Adenomatous polyps (adenomas):These polyps sometimes change into cancer. Because of this, adenomas are called a pre-cancerous condition. The 3 types of adenomas are tubular, villous, and tubulovillous.
- Hyperplastic polyps and inflammatory polyps:These polyps are more common, but in general they are not pre-cancerous. Some people with large (more than 1cm) hyperplastic polyps might need colorectal cancer screening with colonoscopy more often.
- Sessile serrated polyps (SSP) and traditional serrated adenomas (TSA):These polyps are often treated like adenomas because they have a higher risk of colorectal cancer.
Other factors that can make a polyp more likely to contain cancer or increase someone’s risk of developing colorectal cancer include:
- If a polyp larger than 1 cm is found
- If more than 3 polyps are found
- If dysplasia is seen in the polyp after it's removed. Dysplasia is another pre-cancerous condition. It means there's an area in a polyp or in the lining of the colon or rectum where the cells look abnormal, but they haven't become cancer.
What are the symptoms of colorectal cancer ?
Colorectal polyps (abnormal growths in the colon or rectum that can turn into cancer if not removed) and colorectal cancer don’t always cause symptoms, especially at first. Someone could have polyps or colorectal cancer and not know it. That is why getting screened regularly for colorectal cancer is so important.
Signs and symptoms of colorectal cancer include:
- A persistent change in your bowel habits, including diarrhea or constipation or a change in the consistency of your stool
- Rectal bleeding or blood in your stool
- Persistent abdominal discomfort, such as cramps, gas or pain
- A feeling that your bowel doesn't empty completely
- Weakness or fatigue
- Unexplained weight loss
Many people with colorectal cancer experience no symptoms in the early stages of the disease. When symptoms appear, they'll likely vary, depending on the cancer's size and location in your intestine.
What are the Colorectal Cancer Screening Tests ?
Several screening tests can be used to find polyps or colorectal cancer. It is important to know that if your test result is positive or abnormal on some screening tests (stool tests, flexible sigmoidoscopy, and CT colonography), a colonoscopy test is needed to complete the screening process.
Stool Tests for Colorectal Cancer Screening
- The guaiac-based fecal occult blood test (gFOBT)uses the chemical guaiac to detect blood in the stool. It is done once a year. For this test, you receive a test kit from your health care provider. At home, you use a stick or brush to obtain a small amount of stool. You return the test kit to the doctor or a lab, where the stool samples are checked for the presence of blood.
- The fecal immunochemical test (FIT)uses antibodies to detect blood in the stool. It is also done once a year in the same way as a gFOBT.
- The FIT-DNA test(also referred to as the stool DNA test) combines the FIT with a test that detects altered DNA in the stool. For this test, you collect an entire bowel movement and send it to a lab, where it is checked for altered DNA and for the presence of blood. It is done once every three years.
Flexible Sigmoidoscopy for Colorectal Cancer Screening
For this test, the doctor puts a short, thin, flexible, lighted tube into your rectum. The doctor checks for polyps or cancer inside the rectum and lower third of the colon.
How often: Every 5 years, or every 10 years with a FIT every year.
Colonoscopy for Colorectal Cancer Screening
This is similar to flexible sigmoidoscopy, except the doctor uses a longer, thin, flexible, lighted tube to check for polyps or cancer inside the rectum and the entire colon. During the test, the doctor can find and remove most polyps and some cancers. Colonoscopy also is used as a follow-up test if anything unusual is found during one of the other screening tests.
How often: Every 10 years (for people who do not have an increased risk of colorectal cancer).
CT Colonography (Virtual Colonoscopy) for Colorectal Cancer Screening
Computed tomography (CT) colonography, also called a virtual colonoscopy, uses X-rays and computers to produce images of the entire colon, which are displayed on a computer screen for the doctor to analyze.
How often: Every 5 years.
What are the treatment options for colorectal cancer?
The stage of cancer determines how colorectal cancer is treated. The severity of cancer is determined through staging. Surgery, chemotherapy, and radiation are all possibilities for treatment.
What colorectal cancer stages are there?
The extent of invasion through the gut wall, the involvement of lymph nodes (the drainage nodules), and the dissemination to other organs all play a role in determining the different stages of colorectal cancer (metastases). The stages of colorectal cancer are described here, along with the treatment options for each. The damaged portion of the intestine must usually be surgically removed (resection) in most situations. Chemotherapy or — in the case of rectal malignancies — radiation are sometimes used to treat tumors.
Stage 0: The disease stays inside the lining of the colon or rectum in stage 0 lesions, also known as carcinoma in situ. Lesions are not malignancies, however they are at the precancerous stage. As a result, removing the lesion, either by polypectomy via colonoscopy or surgery if the lesion is too big, may be all that is needed for therapy.
Stage I: Colorectal tumors that have developed into the intestine's wall but not expanded beyond its muscular covering or into nearby lymph nodes are classified as stage I. A colon resection, in which the diseased area of the colon and its lymph nodes are removed, is typically the standard therapy for stage I colon cancer. A low anterior resection or an abdominoperineal resection are two options for treating rectal cancer, depending on where it is found.
Stage II is broken down into three parts. The cancer has progressed through the colon wall at the first stage, known as IIA. Colorectal cancer at stage IIB has progressed beyond the large intestine's muscular layers. The cancer has migrated into surrounding tissue by the time it reaches stage IIC. The malignancy has not yet invaded the lymph nodes in all stage II lesions, however. A surgical resection (removal) is usually the sole therapeutic option for this stage of colon cancer, however chemotherapy may be given following surgery. Chemotherapy and/or radiation may be used before or after a surgical resection for a stage II rectal cancer.
In stage III colorectal cancer has gone to the lymph nodes, making it an advanced stage of the illness. Stage III colorectal cancer is divided into three smaller stages once again. Cancer that has gone beyond the colon wall to one to three lymph nodes or a very early tumor in the colon wall that has expanded to four to six lymph nodes are both classified as Stage IIIA. More lymph nodes are damaged in the second stage, IIIB, or the colon wall has a more advanced disease with one to three lymph nodes impacted. In this stage, the cancer has affected the abdominal organs as well. The cancer has migrated to surrounding lymph nodes and is affecting more adjacent abdominal tissue and organs in stage IIIC. Surgery is often performed first, followed by treatment in the case of a colon cancer. For stage III rectal cancer, chemotherapy and radiation may be used before or after surgery.
Stage IV : colorectal cancer has advanced to distant organs such as the liver, lungs, or ovaries in individuals with stage IV colorectal cancer. There are three phases in this level as well. Cancer that has progressed to an organ and lymph nodes located outside of the colon is classified as stage IVA. The cancer has spread to many distant organs and lymph nodes at stage IVB. Not only have distant organs and lymph nodes been affected by stage IVC cancer, but so has abdominal tissue. When cancer has progressed to this level, surgery is usually performed to relieve or avoid problems rather than to cure the patient. In certain cases, the cancer's spread is limited enough that it may be surgically removed entirely. Radiofrequency ablation (heat destruction), cryotherapy (freezing destruction), or intra-arterial chemotherapy may be used to treat minor illness in the liver. Chemotherapy, radiation treatment, or both may be used to alleviate, postpone, or prevent symptoms in stage IV cancer that cannot be surgically removed.
What is the Robotic Surgery of Colorectal Cancer ?
Robotic surgery is a form of minimally invasive colorectal surgery offered under circumstances in which our robotic surgeons believe there is measurable safety and categorical benefit for our patients. Like other minimally invasive techniques, robotic surgery relies on small incisions, which can reduce complication rates when compared to large incision or open surgery. But robotic surgery is a more recent technique, and hasn’t yet been as extensively studied. When used inappropriately, robotic surgery can potentially increase hospital and other medical costs. At the BWell , we’re confident in our ability to provide robotics expertly, appropriately, and only when they will serve the patient’s best interests.
Robotic surgery offers important advantages over laparoscopy, including improved ergonomics and optics for the operating surgeon due to the unique wristed instruments. For rectal cancer specifically, the robot allows for a finer dissection of the rectum out of the tight space where it is located. The advantages of robotic surgery are especially applicable in cases like these, where the safety and outcomes of laparoscopic surgery have not been as well established, perhaps due to the difficulty of laparoscopic pelvic surgery. The improved ergonomics that robotics offer are therefore hugely beneficial in the treatment of colorectal conditions.
In what cases of colorectal cancer is robotic colorectal surgery applicable?
Robotic colorectal surgery as a treatment option for the following conditions:
- Colon cancer
- Rectal cancer
- Inflammatory bowel disease
- Crohn’s disease of the duodenum, small intestine, colon, rectum, and anus
- Ulcerative colitis to restorative total proctocolectomy
- Trans-anal conditions
- Rectal prolapse
- Multivisceral surgery (multiple organ system) for cancer and pelvic organ/rectal prolapse, as part of combined surgery with Urology and Gynecology
What is chemotherapy and why is it important in the treatment of colorectal cancer ?
Chemotherapy is a term used to describe a group of medications that are used to destroy cancer cells. Chemotherapy medications may be administered intravenously (into a vein) by an injection or a pump, or orally (by mouth). Each medicine targets a particular kind of cancer and is given at specified times and in specific dosages. Chemotherapy may be used to treat advanced colorectal tumors that have progressed to lymph nodes (drainage nodules) or other organs.
Chemotherapy of colorectal cancer may be applied in a variety of methods, including:
When colorectal cancer has progressed to other organs, such as the liver or the lungs, primary chemotherapy is utilized. Chemotherapy may be able to decrease tumor nodules, improve symptoms, and extend life in this circumstance since surgery normally cannot remove the malignancy.
Certain rectal cancers are treated with neo-adjuvant chemotherapy before surgery to reduce the tumor and make it easier to remove. The patient is frequently given radiation in addition to chemotherapy in this case.
After the colorectal cancer has been surgically removed, adjuvant chemotherapy may be administered. Some cancer cells may persist in the lymph nodes or other organs if the operation does not completely remove them. To destroy any leftover cancer cells, adjuvant chemotherapy is employed.
Your doctor will discuss the best treatment options for your particular disease with you.
What is immunotherapy and why is it important in the treatment of colorectal cancer?
Colorectal cancer immunotherapy is a relatively new method of treatment. Immunotherapy aims to improve a patient's immune response to cancer cells, allowing them to better fight the illness.
What are the negative effects of chemotherapy in the treatment of colorectal cancer?
Traditional chemotherapy may have the following negative effects:
Appetite loss occurs.
Loss of hair
Mouth ulcers are a common ailment among teenagers.
Chemotherapy may increase the risk of infection (because to low white blood cell counts), bleeding or bruising from small injuries (due to low blood platelet counts), and anemia-related tiredness (because of low red blood cell counts).
Most chemotherapy-related adverse effects will go away after the treatment is finished, however it may take some time.
Monoclonal antibodies' adverse effects vary depending on the medicine. Many of these adverse effects are comparable to those seen while using standard chemotherapy drugs.
Before starting any medicine, talk to your doctor about the possible adverse effects. Tell your doctor if you have any adverse effects. Medications or dietary changes may often be used to treat or prevent them.
Who is at risk and how can colorectal cancer be prevented?
Colorectal cancer affects a wide range of people. Although the specific etiology of precancerous colon polyps that lead to colorectal cancer is unknown, there are several variables that raise a person's chance of getting polyps and cancer in the colon. The following are some of the danger signs:
Age: As we become older, our chances of getting colorectal polyps and cancer rise. Colorectal cancer is more frequent in persons over 50, although it may strike anybody at any age.
Other illnesses include: Inherited factors (Lynch syndrome, familial adenomatous polyposis) and medical diseases (type 2 diabetes, past history of cancer, history of inflammatory bowel illness) may raise your risk of colorectal cancer.
Factors that influence your way of life: If you consume alcohol, smoke cigarettes, don't get enough exercise, and/or are overweight, you may be at a higher risk of having colorectal cancer. Precancerous polyps and colorectal cancer are both increased when you smoke. Colorectal cancer has been related to a diet heavy in fat and calories but poor in fiber, fruits, and vegetables. Many risk factors for colorectal cancer may be reduced by changing one's lifestyle.
Colorectal cancer is linked to a number of illnesses.
Polyps: On the inner wall of the colon or rectum, a variety of polyps may grow. Colorectal cancer may arise from precancerous polyps. People with many polyps, such as adenomas, serrated polyps, or other forms of polyps, are more likely to develop polyposis and colorectal cancer due to a hereditary predisposition. Individuals with three or more colorectal polyps should be treated differently than those with one or two.
Ulcerative colitis and Crohn's colitis are inflammatory bowel diseases in which the colon lining becomes inflamed. Colorectal cancer is more likely to occur in people who have these problems for more than seven years and impact a considerable section of the colon.
Personal history: People who have had colorectal adenomas or cancer before are more likely to have it again. Inflammatory bowel disease (IBD) has also been linked to an increased risk of colorectal cancer.
Colon cancer may "run in" families in certain cases. "Familial colon cancer" is the term for this sort of modestly elevated cancer risk. When a person inherits a copy of a cancer susceptibility gene with a mutation, he or she is said to have hereditary cancer susceptibility. Those who inherit a cancer susceptibility gene mutation have a considerably higher risk of acquiring cancer. Not everyone who has a cancer risk gene mutation, however, will acquire cancer. For several colorectal cancer disorders, genetic testing is available.
Is it certain that I'll get colorectal cancer because of these risk factors?
It is not a certainty that you will get colorectal cancer if you have one or more of these risk factors. These risk factors, however, should be discussed with your doctor. He or she may be able to advise you on how to lower your risk of colorectal cancer.
What is the prognosis when diagnosed with colorectal cancer?
Every individual is unique and reacts to therapy in a unique way. Colorectal cancer patients might have a good prognosis if they get timely and adequate therapy. Colorectal cancer patients' survival rates are determined by the cancer's stage at the time of diagnosis and the patient's reaction to therapy. Furthermore, several recent findings have the potential to improve both the treatment and prognosis of colorectal cancer.
The outcome of colorectal cancer therapy is determined by a variety of variables. Here are a few examples:
The most important issue is the cancer's stage. When you're diagnosed with cancer, the stage you're in might help you figure out how bad things are. Cancers that have not progressed to other organs in the body or lymph nodes are classified as lower staged diseases (stages 0, I, II). With more advanced cancer stages, the survival rate drops. For additional information about colorectal cancer stages, speak with your healthcare professional.
The number of lymph nodes that have been affected is as follows: The lymph system is a circulatory system with a complex network of lymph veins and lymph nodes. The lymphatic system aids the immune system's job in protecting the body from external toxins by coordinating its functions. The more lymph glands afflicted by cancer, the more probable it is to return. When lymph nodes are affected, chemotherapy is typically necessary.
What to do if colorectal cancer has spread to other organs?
Colorectal cancer may spread to other organs including the liver and lungs if it is advanced. Additional chemotherapy or radiation may be required in this situation to help prevent the cancer from spreading further.
The surgical quality is: Having the procedure done by a colorectal surgery specialist. This is particularly true for rectal malignancies, which are more difficult to treat surgically.
Many patients with colorectal cancer go on to have regular lives. Treatments available today have favorable results, but you may need many therapies or a combination of treatments (surgery, chemotherapy, radiation) to have the greatest chance of preventing cancer recurrence. Any changes in your health should be reported to your doctor as soon as possible. This will aid him in determining if you need any extra testing or treatment.