- Cancer of the colon
- Incidence and Risk Factors of colon cancer
- Colon Cancer Symptoms and Signs
- How to spot signs of colon cancer
- Colorectal cancer screening
- Colon cancer Treatment
- What Is Metastatic Colon Cancer?
- Location of Metastases
- Colon cancer stages
- Stage 0 (Carcinoma in Situ)
- Stage I
- Stage II
- Stage III
- Stage IV
- Colon cancer III stage diagnosis
- Colon cancer III stage treatment
- Treatment for the Final Stages of Colon Cancer
- Late Stages of Colon Cancer
- 5 Things You Need to Know About Colon Cancer
Cancer of the colon
For men it is surpassed by prostate and lung cancer, and for women by breast and lung cancer. Though not preventable, colon cancer has a high cure rate when discovered early.
Incidence and Risk Factors of colon cancer
Colon cancer occurs most frequently in persons between the ages of 60 and 79 years. The male-to-female ratio is the same. Risk factors for colon cancer include polyps, some hereditary cancer syndromes (Lynch syndrome, familial adenomatous polyposis), ulcerative colitis and Crohn’s disease. Low-fiber, high-fat diet has been postulated to contribute to the development of colon cancer, but this is yet to be confirmed by scientific data.
Colon Cancer Symptoms and Signs
Colon cancer may grow for years before symptoms become noticeable. Symptoms of colon cancer vary according to location of the tumor within the colon. The colon is divided into the ascending colon, transverse colon and the descending colon. Malignant tumors that arise in the ascending colon present with anemia (low blood count), abdominal pain, blood in the stool and weight loss.
Tumors in the descending colon tend to manifest with chronic constipation or bowel obstruction. Cancer in the transverse colon presents with a mixture of both sets of symptoms.
With the increased screening measures now in place, colon cancer is being discovered at early stages even before symptoms develop. The most common location for colon cancer is the sigmoid colon, which is the segment just before the rectum.
How to spot signs of colon cancer
Let the Screening Warn You
It is really a medical professional who should first spot colorectal concerns in your body. Signs that are noticed during screenings are usually growths called polyps or other early indications of precancerous or cancerous conditions.
These can be more easily addressed than if you forgo the screenings, only to discover the cancer through such symptoms as stomach pain. In other words, you want to catch problems before they ever reach a more advanced stage.
Get Informed, Not Worried
If you worry about getting screened, remember that colon or rectal cancer usually develops over a number of years. This means if cancer is detected early, your chances of being treated successfully climb. Not all the screenings are invasive.
The National Cancer Institute (NCI) states that the fecal occult blood test can detect hidden blood in stool. This test is not expensive or invasive, so it can be performed every year. A “flexible sigmoidoscopy” lets a physician inspect the lower portion of the colon.
A “colonoscopy” examines the entire colon. Invasive procedures come with some risks, which your doctor should advise you on prior to the screening. Researchers are evaluating a “virtual colonoscopy” that allows the physician to see images of the colon, without a probe. NCI is funding a trial to help determine if the virtual colonoscopy is as effective as the regular one in the all-important detection of polyps and cancer.*
Weigh the Benefits
Just the names of these tests can raise your eyebrows, but you may only have the colonoscopy once every 10 years. Ask your doctor what tests are best for you and how often they need to be done. Get an overview of each procedure before you undergo testing. In the past, people have avoided testing because some of the procedures must be done in a hospital or other special facility and some, like the colonoscopy, include bowl-cleansing preparations.
Yet you could find and remove polyps when they are non-cancerous, or you could receive an early diagnosis that in early stages is highly treatable. With this in mind, the screening process becomes more manageable.
Be Proactive Against Polyps
Suppose you are having a colonoscopy and a polyp is found, what then? In some cases, it can be removed during the very same procedure in which it was identified.
Once polyps are removed, they can be examined. Your risks will be reassessed and your doctor will want to discuss a screening schedule with you. The time between screenings can range from months to years, depending upon polyp characteristics.
Between screenings, watch for a change in bowel habits. Contact your physician right away with symptoms such as bloody stool, narrow stools, stomach pain and/or a feeling that you cannot completely empty your bowel.
Colorectal cancer screening
Colonoscopy is the test used to visualize the colon. It also allows the doctor to do a biopsy of any masses seen. If colon cancer is confirmed, other test such as a CT scan may be done to determine if the cancer has spread to any other organs.
The American Cancer Society recommends screening for colon cancer beginning at age 50 years in persons with no identifiable risk factors.
Screening involves a colonoscopy every ten years or a flexible sigmoidoscopy, which is similar to colonoscopy except it does not allow visualization of the entire colon, every five years. Alternatively, a fecal occult blood test (FOBT) can be done yearly. FOBT can be done at home, checking for blood in the stool. If this test is positive, then a colonoscopy must be done.
Colon cancer Treatment
The mainstay of treatment for colon cancer is surgery. Survival is increased when surgery is combined with chemotherapy and/or radiotherapy. Depending on the location of the cancer within the colon, a portion or all of the colon may be removed at the time of surgery.
Colon cancer is a potentially curable disease. Stage I of the disease has a cure rate of above 95 percent. The American Cancer Society places emphasis on early detection via appropriate screening tests.
What Is Metastatic Colon Cancer?
Colon cancer is a type of cancer that originates in the colon and bowel area. When the cancer spreads outside of the colon, it is considered to have metastasized. Colon cancer is highly treatable when it is found early, and is contained or localized. Once it has spread, it can be difficult to treat. Knowing what the signs are, how to get tested and how to treat metastatic colon cancer will ensure prompt diagnosis and care.
The colon is an important part of the human body. This is where the waste from food and by products that pass through the body are stored and pushed out of the body. Both the rectum and the colon form the large intestine. The colon is made up of many different types of cells.
When the cells begin to clump together, they form cancer. Initially, there may be no visible signs of cancer until has it began to grow or spread into nearby organs. Some symptoms of advanced or metastasized cancer include weight loss, dark or bloody stools, diarrhea, fatigue, weakness and shortness of breath. In cases where the tumor has grown, it can begin to obstruct certain areas of the bowel or intestine.
This is called a bowel obstruction, and can turn into an immediate life-threatening condition if surgery is not performed right away to remove or repair the obstruction.
Location of Metastases
Whether the colon cancer was initially diagnosed with mets or has reoccurred with the cancer forming into multiple tumors, the location of the metastases is essential to survival. Areas that colon cancer most commonly can spread to include the liver, kidneys, bone, lungs, brain and lymph nodes.
If the cancer is confined to just one distant location such as the lungs or liver, it is possible that it can be cured or placed into remission. When it has spread to the kidneys, bone or brain—it can be more difficult, if not impossible, to treat. Sometimes, the cancer only spreads to the lymph nodes. This means the cancer was likely caught before it entered the blood stream and affected another primary organ.
Metastatic Colon Cancer treatment options
Treatment options are important for someone with metastatic colon cancer. The first course of treatment is to try and see if the cancer cells can be eliminated and destroyed.
This depends on how advanced and widespread the metastases is. Generally, surgery is initially done to try and safely remove the primary tumor. This may be followed by chemotherapy to destroy in cancer cells that may be left behind. In cases where the tumor cannot be removed, radiation therapy may be used to try to shrink the tumor.
If the cancer has recurred with mets and can not be treated successfully, palliative care will be established to make the person comfortable and free of pain.
Colon cancer is often referred to as “colorectal” cancer, as it can occur in the colon, or large intestine, and/or the rectum, which is the end of the colon.
Colon cancer stages
The American Cancer Society states that as of 2009, colon cancer is the second leading cause of death for men and women in the United States. Colon cancer often has no symptoms, which is why it is not often detected early enough. Symptoms that do occur are changes in bowel movements, blood in the stools, pressure in the bowels, and fatigue. Once diagnosed with colon cancer, the cancer is categorized into a “stage,” which represents how far the cancer has spread in the body.
This staging enables the physician to get an accurate picture of the cancer, and the best method of treatment, and each stage has its own set of symptoms to deal with.
Stage 0 is the earliest stage of colon cancer, where abnormal cells have been found in the lining of the colon. These cells develop into cancer and can spread throughout local tissue. There are often no symptoms in stage 0 colon cancer: It usually is detected in a standard colonoscopy exam.
Stage I colon cancer is diagnosed when the cancerous cells have spread beyond the initial layer of tissue and into deeper tissue layers of the colon. According to the National Cancer Institute, stage I is sometimes referred to as “Dukes A” colon cancer, after C.E. Dukes, who originally published staging for colon cancer in 1932.
Stage II colon cancer actually has sub-stages of A and B. Colon cancer is classified as stage IIA when it has spread past the deeper tissue layers of the colon and into tissues surrounding the colon. Stage IIB cancer is diagnosed when the cancer has spread past the walls of the colon and into organs nearby. This is often referred to as Dukes B.
Stage III colon cancer also has sub-stages of A, B and C. The American Cancer Society reports that stage IIIA is diagnosed when the cancer has spread beyond the colon and into at least three lymph nodes but not to other organs. In stage IIIB, the cancer has spread to the nearby organs and tissues in addition to up to three lymph nodes. In stage IIIC, in addition to spreading to nearby tissues and organs, the cancer is now into at least four lymph nodes. The Duke’s staging system often refers to this stage as Dukes C.
Also referred to as Dukes D, stage IV colon cancer is in its most aggressive and deadly stage. The cancer has progressed past neighboring tissues, into lymph nodes, and is now found in other organs, such as the lungs or liver. According to Cancer Research, UK, this stage is often simply referred to as “advanced” colon, or bowel, cancer.
After a diagnosis of colon cancer, the cancer is staged. Staging is a standardized way of describing the extent and spread of the cancer, which helps guide treatment plans and prognosis. The American Cancer Society describes the American Joint Committee Cancer (AJCC) staging system as the staging typically used for colon cancer. The AJCC staging uses a TNM, or tumor, nodes and metastases, categorization. These categories describe how big or how far the tumor has extended, whether any lymph nodes are involved, and if distant sites are cancerous. Numbers after the letters TNM range from 0 to 4, with 4 being the most severe. If there is an “X” instead of a number, it means the information cannot be determined.
Stage 0 (Carcinoma in Situ)
Stage 0 colon cancer is classified as Tis, N0, M0, according to the American Cancer Society. This is the earliest stage of colon cancer, and means that cancer is only in the in layer of the colon. It may also be called carcinoma in situ. No cancer is in the lymph nodes (N0) and there are no metastases (M0).
Stage I colon cancer is T1-T2, N0, M0. Cancer has grown through the muscle tissue layer of the colon and into the submucosa, which is fibrous tissue under the muscle tissue (T1) or it has grown through the submucosa into the thicker outer muscle layer that helps the intestines contract (T2). There is no cancer in the lymph nodes and no metastases.
The second stage of colon cancer has several sub-stages. Stage IIA colon cancer is classified as T3, N0, M0; this involves cancer that has spread to the outer layers of the colon but has not spread through all the layers. The lymph nodes and distant sites are cancer-free. Stage IIB is colon cancer that is T4a, N0, M0. This is cancer that has spread through the outer colon layers but has not reached nearby organs, and there are no cancerous lymph nodes or metastases. The last sub-stage of Stage II, Stage IIC, describes cancer that has not only spread through the outer layer of the colon, but has also attached to or grown into nearby organs. Despite this growth, no lymph nodes are involved and there are no metastases.
There are three sub-stages in Stage III colon cancer. Stage IIIA can involve T1-T2, N1, M0 (similar to Stage I cancer, but with the involvement of one to three lymph nodes or fat near the lymph nodes); or it may be T1, N2a, M0, which means the cancer is in the submucosa and has also been found in four to six nearby lymph nodes.
Stage IIIB can describe colon cancer that is either T3-T4a, N1, M0, which means the cancer has spread to the outer layers of the colon or through the lining of the stomach (peritoneum) but is not in other organs and is also in one to three lymph nodes or fat around lymph nodes; T2-T3, N2a, M0, which means the cancer has spread to either the muscular layer or the outer layer of the colon and has also been found in four to six lymph nodes; or T1-T2, N2b, M0, which means the cancer has spread to the submucosa or muscular layer of the colon and is also in seven or more lymph nodes.
Stage IIIC colon cancer can be T4a, N2a, M0, which is cancer that has spread through the colon to the peritoneum but has not been found in other organs and has spread to four to six lymph nodes; T3-T4a, N2b, M0, meaning the cancer has spread to the outer layers of the colon OR to the peritoneum and is in seven or more lymph nodes; or T4b, N1-2, M0, which describes cancer that has spread through the outer layer of the colon and is in or attached to other organs or tissues, and is also in one or more lymph nodes.
None of the Stage III cancers have distant metastases.
The last stage of colon cancer, Stage IV, has two sub-stages. Stage IVA is diagnosed as any T, any N, and M1a, which means the cancer may have spread through all of the layers of the colon or not, lymph nodes may or may not be involved, and it has spread to one other distant organ like the lungs. Stage IVB is any T, any N, and M1b, which is the same as IVA, except in this sub-stage, colon cancer has been found in more than one distant part of the body, distant lymph nodes, or distant parts of the stomach lining.
Colon cancer III stage diagnosis
Stage III A
Stage III A colon cancer consists of cancer that has progressed beyond the innermost layer of the wall of the colon to the middle layers, as well as three or less lymph nodes.
Stage III B
This diagnosis is made when the cancer has spread to up to three nearby lymph nodes and past the middle layers of the wall of the colon to nearby tissues around the rectum or colon or past the colon wall to nearby organs or the peritoneum, which is the abdominal wall lining.
Stage III C
In this substage, the cancer is in four or more adjacent lymph nodes, and has also spread to or past the middle layers of the colon wall, to tissues that are close to the rectum or colon or to organs that are close by and/or through the lining of the abdominal wall.
Colon cancer III stage treatment
Colon cancer develops in the large intestine. When it is diagnosed, the doctor will give it a “stage,” which signifies how big the cancer is and how far it has progressed. When classified as stage III, it means the cancer has spread beyond the inner tissue layers where it first formed and is now into other tissues, to other body organs and into the lymph nodes. Because of this progression, the treatment options for stage III colon cancer are more aggressive.
The first line of treatment in stage III colon cancer is surgery. In stage III, the cancer is no longer a small cluster of cells, as in stage I, but instead it has grown larger, affecting more of the colon. Removal of the entire cancerous area of the colon is a must.
The National Institutes of Health refer to this as a bowel resection, as the diseased part of the colon is removed; if there is enough of the colon left, the surgeon will section the two healthy ends back together. If there is not enough of the colon left, he will resection part of the bowel to the outer wall of the stomach and attach a colostomy bag, which collects the body’s waste.
Surgery can cure up to 90 percent of colon cancer cases, as long as the cancer remains in the walls of the colon. However, since in stage III colon cancer the cancerous cells have spread beyond the bowel walls and into the lymph nodes, surgery will help only 30 to 50 percent of patients.
Chemotherapy is often the second stage of treatment after surgery. Chemotherapy is the use of drugs to kill cancer cells within the body. These drugs can be delivered through pill form or by way of intravenous injection. The NIH recommends that patients with stage III colon cancer should receive chemotherapy for six to eight months following surgery.
The recommended chemotherapeutic agent is 5-FU, or 5-fluorouracil, as it has been shown to increase the chance of colon cancer cure among those who have it. The American Cancer Society reports that chemotherapy can lengthen the survival time of many patients.
Radiation is the use of high amounts of energy rays to kill the cancer cells and to shrink the cancer tumors. Radiation can be given from outside the body (external radiation) as well as inside the body. Internal radiation involves implanting radioactive compounds into the tumor.
Radiation is used before and after surgery. Before surgery, it can be helpful in shrinking the size of a colon tumor, making it easier to remove.
After surgery, it is often used in combination with chemotherapy to attack any remaining cancer cells that may have been missed during the surgery. Radiation is usually only used in colon cancer cases when the cancer has attached to the internal organs, and not to treat the spread of the cancer through the lymph nodes.
Treatment for the Final Stages of Colon Cancer
For Stage III colon cancer, the National Cancer Institute lists several treatment options: resection and/or anastomosis (joining the healthy parts of the colon together after removing the diseased part) and chemotherapy; or, under the guidance of your doctor, joining a clinical trial of chemotherapy, radiation and/or antibody therapy. For Stage IV colon cancer, surgery can remove the cancerous areas of the colon, as well as parts of other organs to which the cancer has spread.
You can also join a clinical trial (under your doctor’s care) or, to treat symptoms of metastasized cancer that are causing discomfort, chemotherapy or radiation may be offered. The aim of these treatments is not to cure the cancer, but to make you comfortable and enhance your quality of life.
Late Stages of Colon Cancer
Colon cancer is a type of cancer that involves an area of the large intestine. If the cancer has spread into the rectum or the end of the colon, the patient may have colorectal cancer. This type of cancer generally starts off as benign tumors that are called polyps.
They are usually removed in order to prevent them from turning into cancer at a later date. Once a colon cancer diagnosis has been made, it is staged. Staging helps oncologists and other doctors put the cancer into perspective for the best possible course of treatment. Staging takes place based on the progression of the cancer. These numbers range from I to IV—with IV being the most severe or advanced. In order to determine the correct staging, the doctor combines PET scans, MRIs, X-rays and pathology reports to get an accurate diagnosis and prognosis. For someone who has had their cancer spread from the colon area to other areas of the body, their colon cancer is likely a stage IV. This means that is has spread or metastasized to areas such as the bone, liver, lungs or brain. It may have also spread to the lymph nodes. Stage IV colon cancer with metastases is generally a cancer that is in its late or final stages.
The treatment for the last stages of colon cancer are generally palliative. This means that the oncologist and surgeon generally do not consider utilizing curative treatments. They explore ways to alleviate pain and make the patient comfortable during their last months or weeks of life. The oncologist may, however, recommend that the patient receive surgery to remove a tumor that may be causing pain or discomfort. They may also recommend forms of radiation or hormonal therapy to help reduce the size of the primary tumor. These procedures will only be considered if the patient is not in the dying process and is a strong candidate for a successful recovery.
The prognosis for someone with late-stage colon cancer is poor. According to the American Cancer Society, the five-year survival rate for someone with stage IV colon cancer is only 8 percent. There are many things to consider when it comes to determining a prognosis. The location and size of the primary tumor, what organs the cancer has spread to, the person’s age and any underlying medical conditions all play a role in whether the patient will survive longer with treatment or if treatment isn’t an option due to the extent of the disease. A hospice care team may be utilized to provide end-of-life care and support to the patient and his family.
5 Things You Need to Know About Colon Cancer
Know Your Risks
Researchers know several risk factors increase the chance of developing colon cancer. You can’t change some of these risks, such as having a family history of colon cancer or getting older. However, people more susceptible to developing the disease can stop smoking and reduce the consumption of animal fat, both of which can cause colon cancer. In the future, researchers may pinpoint colon cancer risks with even more precision, and the Human Genome Project may reveal genetic changes that increase the risk of developing colon cancer.
On the Decline
Although colon cancer is the third most common cancer in the United States, its incidence has dropped by more than a quarter since the 1980s. This is due, in part, to the willingness of potential colon cancer patients to submit to something everyone over the age of 50 needs: a colonoscopy. Getting a colonoscopy is similar to going to the dentist. No one looks forward to it, but it’s necessary because doctors can find and remove polyps in the colon before they turn into cancer.
Virtual Color Cancer Detection
Most people dread the invasive colonoscopy or sigmoidoscopy, in which the doctor inserts a thin, lighted tube into the colon to check for abnormal growths. However, the virtual colonoscopy is an exciting new cancer-screening tool still in the developmental stage.
Although this test requires patients to fast and take laxatives before the exam, the doctor takes pictures of the colon with the aid of CAT scan technology, rather than with a camera attached to a tube inserted in the rectum. The development of less-invasive screening procedures is helpful because many eligible adults resist unpleasant screening tests, and colon cancer is highly curable when found early.
It’s Not Just Gas
Early colon cancer may cause few or no symptoms, which is why screening is important. However, when colon cancer patients begin to notice symptoms, it might seem more like a vague annoyance than a sign of cancer. Colon cancer can cause either diarrhea or constipation. Other colon cancer symptoms include feeling gassy or bloated. Although other problems can cause these symptoms, don’t wait for abdominal pain; see a doctor to rule out cancer.
Nip Colon Cancer in the Bud
A vital part of colon cancer research focuses on prevention. The word chemotherapy has negative connotations for many people, but the new colon cancer buzzword is chemoprevention, referring to the use of drugs to stop precancerous polyps from turning into colon cancer. One drug still under investigation is Celebrex.
This drug works at the cellular level to stop an enzyme reaction that may promote the development of colon cancer. Although this drug has some side effects that prevent it from becoming a standard treatment, the research may lead to further drugs to prevent colon cancer.