Colorectal Cancer its Symptoms and Treatment

Colorectal cancer (colon cancer and rectal cancer or bowel cancer) is the enlargement of cancer in the colon or rectum (parts of the large intestine ). It is due to the abnormal enlargement of cells that have the ability to invade or spread to other parts of the body.

Risk factors: 

Risk factors include older age, male gender, high intake of fat, alcohol or red meat, obesity, smoking, and a lack of physical exercise, inflammatory bowel disease (crohn's disease and ulcerative colitis).

Cause:

Genetics: Family history of first degree relatives (such as a parent or sibling) have a two to three fold greater risk of this disease. It occurs in 20% of all cases. A number of genetic syndromes are also associated with higher rates of colorectal cancer and it includes hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome) which is seen in about 3% of people with colorectal cancer. Other syndromes associated include: Gardner syndrome, and familial adenomatous polyposis (FAP) which is rare, occurs in 1% of cases. 

Inflammatory bowel disease : People with inflammatory bowel disease are at greater risk of colon cancer. The risk is high when a person has this for a long period of time and worse is the condition. In those with inflammatory bowel disease less than 2% of colon cancer cases yearly. In those with Crohn's disease 2% get colorectal cancer after 10 years, 8% after 20 years, and 18% after 30 years. In those with ulcerative colitis approximately 16% develop either a cancer precursor or cancer of the colon over 30 years.

Signs and symptoms:

The symptoms and signs of colorectal cancer depend on: location of the tumor in the bowel and
metastasis. Some common signs and symptoms are listed below:

• More often going to the toilet
• Diarrhea
• Constipation 
• Blood in feces (stool).
• Pains in the abdomen
• Bloating in the abdomen
• A feeling of fullness in the abdomen (maybe even after not eating for a while)
• Nausea or Vomiting
• Fatigue
• Weight loss
• A lump in the tummy or a lump in the back passage felt by your doctor
• Unexplained iron deficiency in men, or in women after the menopause

Diagnosis:

Colorectal cancer can be diagnosed by following tests: Fecal occult blood test (known as blood stool test) - A sample of the patient's stool is taken to determine the presence of blood in stool. It can be done at the GP's (general practitioner's, primary care physician's) office. However, the patients can be given a kit that explains how to take the sample at home and the sample is taken to the doctor's office and sent to a laboratory. This test is not 100% accurate because it cannot detect all cancers as it does not bleed in some cases. Even cancers that do bleed often do not do so all the time. So, it is possible that a patient has a negative result, even though he/she has cancer. Even if blood is detected, this may be caused by other illnesses or conditions, such as hemorrhoids.

Stool DNA test : It analyzes several DNA markers that colon cancers or precancerous polyps cells
shed into the stool. A kit with instructions is handed to the patient how to collect a stool sample at home. After collection of sample at home it is brought to the doctor's office, and is then sent to a laboratory. This test is much more accurate for detecting colon cancer than polyps. However, it cannot detect all DNA mutations which may indicate that a tumor is present.

Flexible sigmoidoscopy: A sigmoidoscope is used by physician. It is flexible, slender and lighted tube, to examine the patient's rectum and sigmoid (the sigmoid colon is the last of the colon, before the rectum). This procedure takes only a few minutes and is not painful; but it might be uncomfortable to patient. There is a risk of perforation of the colon wall. If a polyps or colon cancer is detected physician will carry on a colonoscopy to examine the entire colon and take out polyps that are present and examined it under a microscope.

A sigmoidoscopy will only detect polyps or cancer present at the end third of the colon and the rectum. If there are any in any other parts of the digestive tract it will not detect them.

Barium enema X-ray:  Barium is a contrast dye that is placed into the patient's bowel in an enema form to visualised on an X-ray. In a double-contrast barium enema air is added as well. The lining of the bowel is filled n coated with barium which creates a clear image of the rectum, colon, and occasionally of a small part of the patient's small intestine. This procedure is carried out along with a flexible sigmoidoscopy to detect any small polyps. If the barium enema X-ray detects anything abnormal, the physician may recommend a colonoscopy.

Colonoscopy: The physician uses a colonoscope, which is much longer than a sigmoidoscope. It is
attached to a video camera and monitor. The physician can see the whole of the colon and rectum.
If polyps is detected during this exam it can be removed there and then - sometimes tissue samples
(biopsies) may be taken instead. Prior to the exam the patient may be given a large amount of laxative fluid to clean out the colon.

CT colonography (virtual colonoscopy):  A CT (computerized tomography) machine is used to
take images of the colon. The patient needs to have a cleared colon for this exam to be effective. Even if anything abnormal is detected, the patient will then need conventional colonoscopy. It is a
effective diagnostic procedure.

Ultrasound scan: Sound waves are used to help show if the cancer has spread to another part of the body.

Magnetic resonance imaging (MRI): It gives a three-dimensional image of the bowel and may help the doctor in his/her diagnosis.

Staging the cancer:

The stages of colon cancer are:

Stage 0 (Duke A stage): It is the earliest stage. It is still within the mucosa (inner layer) of the colon or rectum - also known as carcinoma in situ .
Stage I ( Duke B stage): It has spread through the inner layer of the colon or rectum, but has not yet spread beyond the wall of the rectum or colon.
Stage II (Duke C stage): It has spread through or into the wall of the colon or rectum. However, it has not reached the nearby lymph nodes yet.
Stage III ( Duke D stage): It invade the nearby lymph nodes , but it has not yet affected other parts of the body.
Stage IV ( Duke E stage): It has spread to other parts of the body, including other organs, such asthe liver, the membrane lining the abdominal cavity, lung, or ovary.

Recurrent:The cancer has returned after treatment. It may come back and affect the rectum, colon, or elsewhere in the body.

Treatment for colorectal cancer:

The patient's treatment will depend on several factors, including its size and location, the stage of the cancer, whether it is recurrent or not, and the current overall state of health of the patient.Treatment options include surgery, chemotherapy and radiotherapy.

Surgery: Surgery is done to remove the affected malignant tumors and any lymph nodes that are nearby lymph nodes is removed by surgeons because they are the first place cancers that tend to spread to. The bowel is usually sewn back together. Sometimes the rectum may need to be taken out
completely - a colostomy bag is then attached for drainage. The colostomy bag collects stools and is generally placed temporarily - sometimes it may be a permanent measure if it is not possible to join up the ends of the bowel. Surgery may be the only treatment necessary to cure the patient of colorectal cancer if it is diagnosed at early stage. Even if surgery does not cure the patient, it will ease the symptoms.

Chemotherapy:Chemotherapy involves using a medicine (chemical) to destroy the cancerous cells. It is commonly used for colon cancer treatment. It may be used to shrink the tumor before surgery.

Radiotherapy:Radiotherapy uses high energy radiation beams to destroy the cancer cells, and also to prevent them from multiplying. This treatment is more commonly used for rectal cancer treatment. It may be used to shrink the tumor before surgery. Doctors may order both radiotherapy and chemotherapy after surgery as they can help lower the chances of recurrence.

Recovery from colorectal cancer:

A patient's recovery depends of the following factors:

• The cancer stage when diagnosis was made.
• Whether a blockage or hole was created in the colon by the cancer.
• Whether the cancer reoccured.
• General condition of patient health.

Prevention:

Regular screenings: Individual over age of 60 and a family history of colorectal cancer should start screening after the age of 50.

Nutrition: Diet we take should have plenty of fiber, fruit, vegetables, and good quality carbohydrates . Consumption of red meat and processed meat should be lowered down to a minimum, or cut them out altogether. Switch from saturated fats to good quality fats, such as avocado, olive oil, fish oils , and nuts. However, it can lower the risk of developing cancer.

Exercise:Exercise should be done regularly. Moderate, regular exercise has significant impact on lowering a person's risk of developing colorectal cancer.

Bodyweight: Bodyweight should be moderate and healthy. Overweight or obesity raises a person's risk of developing many cancers, including colorectal cancer.