Join the experts at New York-Presbyterian/Columbia University Medical Center on Saturday, March 15, for Colorectal Cancer Awareness Day. This patient-focused event will highlight the latest advances in the screening, diagnosis, and treatment of colorectal cancer.
To learn more about colorectal cancer and the topics that will be covered at this event, we spoke with Dr. P. Ravi Kiran, chief of colorectal surgery at Columbia and program director of Colorectal Cancer Awareness Day.
Dr. Kiran, in recent years colorectal cancer has become increasingly common in the United States. Why is this?
Dr. Kiran—Well, the simple fact that people in general are living longer contributes to higher rates of colorectal cancer. But more specific causes include poor dietary habits, lack of exercise, and the prevalence of saturated fats in our diets. In addition, there is a genetic component to the disease that makes it more common in certain populations.
What are some other risk factors for developing colorectal cancer?
Dr. K—Age is a major risk factor. As we grow older, we are at a higher risk for developing colorectal cancer. Additionally, some ethnicities are more prone to the disease, and certain conditions that involve the colon and rectum—like ulcerative colitis and inflammatory bowel disease—can predispose people to colorectal cancer.
What are the most common signs and symptoms of colorectal cancer?
Dr. K—Colorectal cancer can frequently be a quiet disease. We actually hope that it is quiet when detected, because once symptoms arise it is usually late in the development of the disease. This is why regular screening and early detection are so important.
In addition, part of the problem with detection is that symptoms can often be non-specific. For example, many patients can experience rectal bleeding, which can also be attributed to other common conditions like hemorrhoids.
The symptoms of colorectal cancer also vary depending on the location of the disease. Cancers located on the left (lower portion) of the colon can manifest as bleeding. This is because the left portion tends to be narrower and tumors located there tend to be circular in structure, which can lead to symptoms such as obstruction, abdominal bloating, and changes in bowel habits.
On the right side (upper portion), the colon is wider, so there is less chance for obstruction. Also, the contents of the colon are liquid, as opposed to the solid contents of the left. Because the right side is far away from the rectum and anal canal, many patients will not have any obstruction or blood in their stools. So these patients may not present with any symptoms, and the only way they may know something is wrong is if they develop anemia.
At what point should people seek treatment if they develop symptoms that could indicate colorectal cancer?
Dr. K—Anyone with symptoms such as change in bowel habits, rectal bleeding, bloating, weight loss, unexplained pain in the abdomen, or unexplained loss of appetite should seek medical advice and get a proper evaluation.
What are the most common screening methods used to detect colorectal cancer?
Dr. K—The gold-standard screening method is still colonoscopy, because it allows doctors to look at the entire colon. If a polyp is detected during a colonoscopy, it can be dealt with immediately, and if the person already has cancer it can be biopsied.
There are, however, other screening methods in use. One tests the stool for occult blood. This test is used to determine if there is any blood in the stool, but it is not very specific. Results can be positive when there is nothing in the colon, or they can be negative and the person could actually have cancer. This is because the test shows only whether there is blood present in the stool at the time of the test.
Two other tests are sigmoidoscopy, which looks only at the lower half of the colon, and CT colonography (virtual colonoscopy), which picks up problems in the colon. If the results of CT colonography indicate an abnormality, a colonoscopy must then be done to confirm or refute the results.
What are the most common treatment options for colorectal cancer?
Dr. K—Treatment depends on the stage of the disease and the health of the patient. In its early stages, the disease can be managed endoscopically, and in most cases precancerous polyps can be removed during a colonoscopy. If the polyp has what we call “good” characteristics—meaning that it doesn’t have malignant-looking cells—then this may be the only treatment required.
However, the most common way of managing colon cancer is to remove the section of the colon containing the cancer and surrounding lymph nodes. This is called an en bloc resection and, depending on the stage of the disease, the patient may or may not need further treatment. If there is involvement of the lymph nodes or other organs, or if the patient is young, and doesn’t have involvement of the lymph nodes but the tumor has characteristics that suggest it may be aggressive, we might recommend that the patient undergo chemotherapy. When cancer occurs in the rectum (the portion of the large intestine located in the pelvis), radiotherapy is sometimes also required.
In certain cases, we may treat patients with chemotherapy and/or radiation prior to surgery, to shrink the tumor so it can be removed with good margins, which can be a problem with some rectal cancers. That is the principal goal of any cancer surgery: to remove the tumor with good margins. Similarly, when cancer may have spread (metastasized) from the colon to other organs (metastases), treatment with chemotherapy may be needed prior to surgery.
At what age should people begin to get screened for colorectal cancer? How often should these screenings be done?
Dr. K—The recommended age for beginning regular colonoscopies is 50, but this is for the average-risk population. For a person with a family history, it may be much younger than 50. In general, we recommend that patients begin screening at 10 years younger than the youngest person affected by colorectal cancer in their family. So, if a patient is diagnosed at 55, we recommend that the immediate relatives start screening at age 45.
How frequently people get screened really depends on their risk, which is based on a combination of family history, genetics, and the results of prior screenings.
Every ten years: For average-risk individuals without any genetic predisposition, who show no signs of cancer during a colonoscopy.
Every five years: For average-risk individuals without any genetic predisposition, but who have been found through a colonoscopy to have precancerous polyps .
Every three years: For individuals who have been found to have three or more adenomatous polyps.
These are just general guidelines, as our recommendations really depend on a variety of factors unique to each patient. Some patients may require more frequent screening.
What advice would you give to somebody recently diagnosed with colorectal cancer?
Dr. K—In this day and age, colorectal cancer is certainly curable, but early detection and diagnosis are crucial. Once the disease is diagnosed, adequate staging followed by a multidisciplinary approach that combines the recommendations of various specialists can make a big difference in the outcome. And while a lot still depends on a variety of factors—including the individual genetics of the patient, the stage of the tumor, and the location of the tumor—there is now a very good outlook for patients diagnosed with colorectal cancer.
To learn more, and to register for the upcoming event, please visit our events page:
Colorectal Cancer Awareness Day