Colorectal Cancer

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How common is cancer of the colon and rectum?

Colorectal cancer is the third-most common cancer in humans, topped only by cancer of the lungs and female breasts. More than 150,000 people in the United States each year discover they have cancer of the colon or rectum, and approximately 46,000 will die from it this year alone. The incidence starts to rise at the age 40 and the peak is between ages 60 to 75. Colon cancer is more common among women and cancer of the rectum among men. About 5% of the patients have both (synchronous cancer).

Does genetics play a role in colorectal cancer?

To some degree yes, but there is really a low genetic predisposition to cancer of the large intestine. Exception to this is seen in "cancer-families" and "colon cancer-families," where colorectal cancer victimizes family members cross several generations, usually occurring before the age of 40.

What are the other predisposing factors?

These factors include chronic ulcerative colitis, ganulomatous colitis, and familial polyposis. The older the person is, the higher the risk.

Are meat-eaters more prone to colorectal cancer?

It appears to be so, because colorectal cancer is found more prevalent in populations that low-fiber diets that are high in animal proteins, fats, and refined carbohydrates. The incidence of colorectal cancer is indeed high among those who eat red meat (pork, beef, etc) compared to those who eat high fiber diets (vegetables, fruits, wheat, bran, etc) and fish.

What is the mechanism in the formation of this cancer?

This question is not yet settled. It is postulated that carcinogens (cancer- causing agents) may be from the low-fiber food (especially red meat) we eat, or produced from the resulting biliary or intestinal secretions following bacterial action, which transforms these into carcinogens. Colorectal caner is one reason why we recommend abstinence from red meat and staying on high-fiber diet of vegetables and fruits, and fish. The other is, of course, to minimize the occurrence of heart attack and stroke.

What are the signs and symptoms of colorectal cancer?

The person may not have symptoms at all. It could be so subtle, like fatigue and anemia. Blood in the stool (black or bloody red stools) is one common sign. The others include change in the bowel habits, diarrhea or constipation, stools more slender or flatter than usual, stomach discomfort, bloating, fullness, abdominal cramps, frequent gas pains, unexplained weight loss, a sensation that the rectum does not empty completely. Not all these symptoms and signs need to be present, or necessary, to suspect possible presence colorectal cancer. Any one of these, if persistent, should alert one to seek medical help.

Can't these symptoms be due to other conditions?

Most definitely, yes. Some of these symptoms could also be seen in hemorrhoids, ulcers or inflamed colon, etc. But because colorectal cancer is a deadly disease, one cannot be complacent or indifferent when any of these signs or symptoms is present. To rule out the presence of colorectal cancer, the individual should see a physician, who will interview and examine the patient and perform some tests to make a diagnosis. As with other forms of cancer, early diagnosis is essential and life saving.

What are intestinal polyps?

These are small benign tumors (not cancerous growths) in the colon, but they may become cancerous over a period of time, hence termed "precancerous." Detecting and removing polys is one strategy to prevent colorectal malignancy. In most instances, polyps can be removed by colonoscopic procedure (long, tube-like flexible fiberoptic lighted "tele" scope, about the diameter of the index finger, inserted thru the anus, to inspect the rectum and colon, make biopsy and/or excision of polyps). This saves the patient from an abdominal surgery. About 60% of all colorectal cancers are within the reach of flexible fiberoptic sigmoidoscopy, popularly known as colonoscopy.

When should colonoscopy be done?

Everyone 50 years old and older should have an annual fecal occult blood test and a prophylactic colonoscopy every 3 to 5 years. Since blood in the feces is one of the earliest sign of colorectal cancer, testing for blood in the stools yearly among those 50 and older is essential, and could be lifesaving. And so with prophylactic colonoscopy.

How do we prevent colorectal cancer?

As alluded to above, a high-fiber (fruits and vegetables, bran, oat, wheat) and fish diet will tremendously reduce the risk of colorectal cancer. Therefore, staying away from animal protein, like red meat (pork, beef and anything made of these) is a big factor in preventing the development of colorectal cancer, besides heart attack and stroke. Daily exercises make our body healthier and more resistant to illnesses. Abstinence from tobacco is a must. Checking your stools for blood every time you defecate and reporting any warning signs listed above to your physician will help. For those 50 and older, having a yearly fecal occult blood test and a colonoscpy every 3 to 5 years, is strongly recommended for early detection and cure of the disease.

What is the treatment for colorectal cancer?

Depending on the stage and location of the colorectal cancer, the primary strategy is wide surgical resection of the cancer and regional lymphatic drainage. Cure is possible in 75% of surgical patients. For cancer limited to the mucosa (surface lining of the wall of the colon), 5-year survival is about 90%; those cancer going deeper into the mucularis propia (muscle-layer of colon), 80%; those with positive lymph nodes, meaning cancer already spreading to the lymph nodes, 30%. Other modalities of treatment includes pre-operative radiotherapy, adjuvant radiotherapy, chemotherapy. When surgery and/or any of these other modalities are indicated will depend on the location, extent and stage of the colorectal cancer.

What is the outlook for colorectal cancer patients?

There is no question that the outlook for colorectal cancer, and most other cancers in general, is much better today. But we cannot overemphasize the common-sense wisdom that prevention is the best "treatment," especially when dealing with any potentially deadly disease like cancer, heart attack, stroke, AIDS, etc. New hopes for cancer victims are in the pipeline of dozens of research/clinical laboratories in the United States and other countries around the world. Before the advent of the oral medications for pulmonary tuberculosis, the disease acted like cancer, spreading from the lungs to the brain, bones, liver, kidneys, spleen, lymph nodes, etc. We predict that someday soon, hopefully in the not too distant future, many forms of cancers, if not all, will be cured by simply taking anti-cancer pills. In the meantime, it behooves each one of us to play an active role in protecting ourselves from becoming cancer victims by living a healthy lifetyle and by being ever-vigilant about our health and that of our loved ones.

©2003Raoul R. Diez, M.A.O.D.