Colon cancer is the number two cause of cancer death for both men and women combined. However, it is also one of the most preventable of cancers because doctors can identify and remove the pre-cancerous growth know as a polyp.
PATIENTS DO NOT HAVE any symptoms from small polyps; they are clinically silent. Large polyps can sometimes cause microscopic bleeding into the colon and result in anemia (low red blood cell count). Doctors now believe that cancers of the colon arise from polyps. However, not all polyps turn into malignant colon cancer. In fact, most polyps will remain benign. For the small percentage of polyps that will turn malignant, the process probably takes years — on the order of five to 15 years. Therefore, there is a large window of opportunity to screen for colorectal polyps and remove them. Since doctors cannot determine by appearance, which polyps will remain benign and which will turn malignant, all polyps are considered “potential” cancers and removed. Once removed, the threat of that polyp one-day turning cancerous is completely eliminated. This is why it is so important to get screened for colorectal cancer when you are feeling well.
THE GOOD NEWS AND BAD NEWS
Unfortunately, the majority of people will never address colorectal cancer screening with their health care providers. Without appropriate prevention and screening, symptoms of colorectal cancer may develop.
The good news: Colon cancer is curable if found early. In fact, if the cancer is confined to the wall of the colon, surgical removal may be the only treatment that is required. Some of us may recall that President Regan had colon cancer diagnosed and removed when he was in office.
The bad news: Colon cancer discovered late, especially if it has spread to lymph nodes and other organs, can be lethal. Although chemotherapy and radiation (if the rectum is involved) may be effective, the prognosis is worse once the cancer spreads outside the confines of the colon wall.
This is why any symptom of colon cancer cannot be ignored. If found early, colon cancer can be cured! However, if one waits and ignores symptoms until it can no longer be avoided, the disease may spread.
SYMPTOMS OF COLON CANCER: Blood in the stool:
Most of the time, blood in the stool is not due to cancer. Hemorrhoids (rectal veins) are the main culprit. Sometimes what people describe as blood may turn out to be food residue from beats or tomatoes. So, if you notice blood with a bowel movement, don’t panic. However, this symptom should not be ignored and a physician should evaluate any patient with rectal bleeding.
Change in bowel habits:
This refers to a new but persistent change in the size, shape, frequency and consistency of the stool. In other words, someone may notice the new onset of constipation and/or diarrhea. What is important to notice is the change. This is not referring to the person who has a lifelong history of diarrhea and/or constipation. Instead, for example, a person who always had a tendency towards diarrhea may notice a few weeks of new constipation, poor bowel evacuation, and perhaps more bloating and abdominal pain in the setting of a colon cancer blocking the passage of fecal material.
Change in shape or size of stool:
If a cancer is narrowing the opening of the lower part of the colon, the stool may become persistently pencil thin with a decreased size and caliber (thickness). The important feature to notice in this situation is that the stool is persistently altered from what an individual would consider normal.
Do not panic if you are saying to yourself, ” I always have abdominal discomfort.” Abdominal discomfort is common in healthy individuals without cancer. In the setting of colon cancer, abdominal discomfort usually presents with other symptoms described here, such as a change in bowel habits and/or anemia. If the pain is from a cancer partially blocking the colon, it is often associated with bloating, cramping and nausea. If the pain is from the cancer itself, it may be localized to one specific point in the abdomen and be reproducible with palpation.
Anemia refers to a lowering of the red blood cell count. Fatigue can be a result of anemia because the red blood cells are responsible for delivering oxygen to the body tissues. In the setting of colorectal cancer, the anemia may be caused by a persistent, microscopic amount of chronic blood loss in the stool. The anemia is not usually caused by large amounts of blood lost directly into the stool. Instead, it is low iron (iron deficiency) that often causes the anemia seen with colon cancer. Why does this occur? Iron is essential for the formation of functioning red blood cells. Without iron, the body is unable to produce more red blood cells. In the setting of microscopic, persistent bleeding from colon cancer, iron is lost with the red blood cells and can slowly deplete the total body stores of iron. The production of new red blood cells is reduced and eventually the total red blood cell count decreases causing anemia. For menstruating women, iron deficiency is commonly seen because of the monthly loss of blood with the period. However, for men, iron deficiency is uncommon and always needs to be further investigated by a physician.
Unexplained weight loss:
Most people want to lose weight. Occasionally, someone may notice that they are losing weight without any change in their diet or activity. Unexplained weight loss is frequently associated with fatigue and should be evaluated by a physician. Besides cancer, this symptom can be due to depression, an eating disorder, food avoidance due to abdominal pain, and malabsorption.
THE BOTTOM LINE In our crisis-oriented health care system, we often wait for symptoms of a disease before we seek medical attention. Even worse, once symptoms present, we often ignore them. In the case of colorectal cancer, do not ignore the symptoms described above. Better yet, do not even wait for symptoms to develop. If you are over the age of 50, you should be screened for this disease. If you have a family history of cancer, discuss with your health care provider when screening should begin; it may start at age 40 or earlier. Colorectal cancer is often preventable and curable if caught early. Discuss the options for colorectal cancer prevention and screening with your health care provider. Take responsibility for your own health and learn your family medical history.
With all the uncertainty in our lives, especially when it comes to our own health, wouldn’t it be nice if colorectal cancer was one less thing you had to worry about?
Dr. Mark Pochapin is Assistant Professor of Medicine at Weill Medical College at Cornell University and Assistant Attending Physician at New York Presbyterian Hospital.