Alale is the most powerfull center in medical tourism - All you need to Know about Colon Cancer

Colon Cancer
 

Colon or in another term, the large intestine, is the lowest part of the digestive system. Inside the colon, water and salt from solid wastes are extracted before the waste moves through the rectum and exits the body through the anus.

Cancer is a class of diseases characterized by out-of-control cell growth. Most colon cancers originate from small, noncancerous (benign) tumors called adenomatous polyps that form on the inner walls of the large intestine.

Some of these polyps may grow into malignant colon cancers over time if they are not removed during colonoscopy - a procedure looking at the inner lining of the intestine.

Colon cancer cells will invade and damage healthy tissue that is near the tumor, causing many complications.
 

Excluding skin cancers, colorectal cancer is the third most common cancer diagnosed in both men and women in the United States. The American Cancer Society’s estimates for the number of colorectal cancer cases in the United States for 2017 are:

• 95,520 new cases of colon cancer
• 39,910 new cases of rectal cancer

Colorectal cancer is the third leading cause of cancer-related deaths in women in the United States and the second leading cause in men. It is expected to cause about 50,260 deaths during 2017.

Symptoms

Signs and symptoms of colon cancer include:

• A change in your bowel habits, including diarrhea or constipation or a change in the consistency of your stool, that lasts longer than four weeks
• 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

Talk to your doctor about when you should begin screening for colon cancer. Guidelines generally recommend that colon cancer screenings begin at age 50. Your doctor may recommend more frequent or earlier screening if you have other risk factors, such as a family history of the disease.

Causes

• Colon cancer usually derives from precancerous polyps that exist in the large intestine.
• Cancer occurs when a cell's gene mutations make the cell unable to correct DNA damage and unable to commit suicide. Similarly, cancer is a result of mutations that inhibit certain gene functions, leading to uncontrollable cell growth.
• Age and diet are important risk factors for colon cancer; around 90 percent of those diagnosed are over 50. Diets that are low in fiber and high in fat, calories, and red meat and processed meats increase the risk of developing colon cancer
• Cancer can be the result of a genetic predisposition that is inherited from family members. It is possible to be born with certain genetic mutations or a fault in a gene that makes one statistically more likely to develop cancer later in life.

The most common forms of inherited colon cancer syndromes are:

• Hereditary nonpolyposis colorectal cancer (HNPCC). HNPCC, also called Lynch syndrome, increases the risk of colon cancer and other cancers. People with HNPCC tend to develop colon cancer before age 50.
• Familial adenomatous polyposis (FAP). FAP is a rare disorder that causes you to develop thousands of polyps in the lining of your colon and rectum. People with untreated FAP have a greatly increased risk of developing colon cancer before age 40.
  

Diagnosis

In order to diagnose colon cancer, physicians will request a complete physical exam as well as personal and family medical histories. Diagnoses are usually made after the physician conducts a colonoscopy or a barium enema x-ray.

Prognosis

After a diagnosis is made, doctors determine the stage of the cancer. The stage determines which choices will be available for treatment and informs prognoses.

The standard cancer staging method is called the TNM system:

• T - indicates the size and direct extent of the primary tumor, or degree of invasion into the intestinal wall
• N - indicates the degree to which the cancer has spread to nearby lymph nodes
• M - indicates whether the cancer has metastasized to other organs in the body

Risk factors

Factors that may increase your risk of colon cancer include:

• Older age. The great majority of people diagnosed with colon cancer are older than 50. Colon cancer can occur in younger people, but it occurs much less frequently.
• African-American race. African-Americans have a greater risk of colon cancer than do people of other races.
• A personal history of colorectal cancer or polyps. If you've already had colon cancer or adenomatous polyps, you have a greater risk of colon cancer in the future.
• Inflammatory intestinal conditions. Chronic inflammatory diseases of the colon, such as ulcerative colitis and Crohn's disease, can increase your risk of colon cancer.
• Inherited syndromes that increase colon cancer risk. Genetic syndromes passed through generations of your family can increase your risk of colon cancer. These syndromes include familial adenomatous polyposis and hereditary nonpolyposis colorectal cancer, which is also known as Lynch syndrome.
• Family history of colon cancer. You're more likely to develop colon cancer if you have a parent, sibling or child with the disease. If more than one family member has colon cancer or rectal cancer, your risk is even greater.
• Low-fiber, high-fat diet. Colon cancer and rectal cancer may be associated with a diet low in fiber and high in fat and calories. Research in this area has had mixed results. Some studies have found an increased risk of colon cancer in people who eat diets high in red meat and processed meat.
• A sedentary lifestyle. If you're inactive, you're more likely to develop colon cancer. Getting regular physical activity may reduce your risk of colon cancer.
• Diabetes. People with diabetes and insulin resistance may have an increased risk of colon cancer.
• Obesity. People who are obese have an increased risk of colon cancer and an increased risk of dying of colon cancer when compared with people considered normal weight.
• Smoking. People who smoke may have an increased risk of colon cancer.
• Alcohol. Heavy use of alcohol may increase your risk of colon cancer.
• Radiation therapy for cancer. Radiation therapy directed at the abdomen to treat previous cancers may increase the risk of colon cancer.
  

Treatments for colon cancer

Cancer treatment depends on the type of cancer, the stage of the cancer (how much it has spread), age, health status, and additional personal characteristics. There is no single treatment for cancer, but the most common options for colon cancer are surgery, chemotherapy, and radiation therapy.

Treatments seek to remove the cancer and/or relieve painful symptoms that the cancer is causing.

Surgery

Surgery to remove part of or the entire colon is called colectomy. During colectomy, a surgeon will remove the part of the colon containing the cancer as well as the marginal area close to the cancer.

Also, nearby lymph nodes are also usually removed. Depending on the extent of the colectomy, the healthy portion of the colon will either be reattached to the rectum or attached to an opening in the wall of the abdomen called a stoma. This latter option is called a colostomy, and waste will exit the body through the stoma into a colostomy bag, instead of exiting through the rectum.

In addition to invasive surgeries like colectomy, doctors can remove some small, localized cancers using endoscopy.

Laparoscopic surgery (using several small incisions in the abdomen) may also be an option to remove larger polyps.

Palliative surgery might also be employed to relieve symptoms for cancers that are advanced or untreatable. This type of surgery will try to relieve blockage of the colon or to inhibit other conditions to relieve pain, bleeding, and other symptoms.

Chemotherapy

Chemotherapy utilizes chemicals that interfere with the cell division process - damaging proteins or DNA - so that cancer cells will become damaged and die. These treatments target any rapidly dividing cells (not necessarily just cancer cells), but normal cells can usually recover from any chemical-induced damage, while cancer cells cannot.

Chemotherapy is generally used to treat cancer that has spread or metastasized because the medicines travel throughout the entire body. Treatment occurs in cycles so the body has time to heal between doses. However, there are still common side effects such as hair loss, nausea, fatigue, and vomiting. Combination therapies often include multiple types of chemotherapy or chemotherapy combined with other treatment options.

One large-scale study has shown that daily low-dose aspirin improves the survival of patients with certain gastrointestinal cancers, such as colon cancer. While the mechanism is not well understood and aspirin's role in prevention has not been well studied, this information provides another possible adjunctive treatment option.

Radiation

Radiation treatment, also known as radiotherapy, destroys cancer by focusing high-energy rays on the cancer cells. This causes damage to the molecules that make up the cancer cells and leads them to die.

Radiotherapy uses high-energy gamma-rays that are emitted from metals such as radium or high-energy x-rays. Radiotherapy can be used as a standalone treatment to shrink a tumor or destroy cancer cells; it is also used in combination with other cancer treatments.

Radiation treatments are not often used for early stage colon cancers, but may be employed if early stage rectal cancer has penetrated the wall of the rectum or traveled to nearby lymph nodes.

Side effects of radiation therapy may include mild skin changes resembling sunburn or suntan, nausea, vomiting, diarrhea, and fatigue. Patients also tend to lose their appetites and have trouble maintaining weight, but most side effects subside a few weeks after completing treatment.

Prevention of colon cancer

Colon cancer is the third most common cause of cancer death in the U.S., and it is the second most prevalent type of cancer. Regular annual screening for both men and women aged 50 to 75 years is recommended by the U.S. Preventive Task Force.

The American Cancer Society suggests screening tests, particularly colonoscopy, for early detection of colon cancer. Colonoscopy is the best method, because it will visualize the entire colon and can remove polyps during the procedure. Other screening tests include fecal occult blood tests (annually), stool DNA testing, flexible sigmoidoscopy (every 5 years), and CT colonography (every 5 years).

These frequency recommendations depend, however, on a person's particular risk of colon cancer due to other risk factors.

In general, physicians recommend standard preventive measures such as keeping a healthy weight, exercising, and increasing consumption of fruits, vegetables, and whole grains while decreasing saturated fat and red meat intake. In addition, people are recommended to limit alcohol consumption and quit smoking.

Dr. Felice Schnoll-Sussman, a gastroenterologist from the NewYork-Presbyterian/Weill Cornell Medical Center, said that it is important for people to realize that with proper screening, colon cancer cannot only be detected early, but may also be prevented from developing.

Sources: medicalnewstoday, mayoclinic, cancer.org