How Genetic Testing for Colon Cancer Helps Patients Understand their Family’s Risk

Genetic testing can provide great insight into disease predisposition, type, and onset as well as progression. As such, it can help not only those who are immediately affected but also their loved ones remain informed and in the know. Being aware of disease behavior provides a sense of relief, which, in turn, improves a situation greatly. Being informed about another person’s disease has several benefits. It is a great way to provide support for a loved one. By knowing what they are going through, you not only understand them better, but you might also be better able to help. Genetically speaking, being informed about genetic testing results of a family member benefits you, too, which is especially the case for inherited diseases, such as breast cancer, bowel cancer, hereditary colorectal cancer, and, of course, hereditary colon cancer. Since genetic mutations are passed on between family members, knowing the genetic background of your relatives is, in a way, insight into your own genetic testing expectations.

But, before we get into how the aforementioned genetic mutations specifically apply to genetic testing for colon cancer, let’s first discuss hereditary colon cancer a bit.

What is colon cancer?

Just like with all other cancers, colon cancer is the result of cells changing as well as growing uncontrollably. In most cases of colon cancer, the beginning marked by small masses of cells within the intestine. The small benign masses, also called polyps, can either be benign without any symptoms whatsoever, but they can also develop into cancers. When this happens in the large intestine (colon), which also known as the final part of the digestive tract, the result is colon cancer. And since these masses can also form in the rectum as well, the disease is often referred to as colorectal cancer.

Doctors can easily detect polyps as well as remove them via a flexible video camera or scope that enables looking at as well as inside the colon. This procedure is called a colonoscopy. If any of your family members have had colon cancer, you should probably screen yourself, too, regardless of age. The guidelines to get tested begging at the age of 50 years old do not apply to those whose family members have suffered from the disease. While many people do not experience any symptoms associated with colon cancer, there are several ailments that should not go unattended. These include fatigue, a feeling that the bowel is not emptied completely, unexpected weight loss, rectal bleeding as well as bloody stools, stomach discomforts such as persistent gas and/or cramps, and a change in bowel movements such as different frequencies, diarrhea, and constipation.

What is colon cancer

In terms of the genetics, an estimated 5–10% of colorectal cancer cases developas a result of heritable mutations—a genetic change that can be passed from mother to child. Familial adenomatous polyposis (FAP) as well as hereditary non-polyposis colorectal cancer (HNPCC), also called Lynch syndrome, are the most common genetic syndromes associated with colon cancer. Individuals who have the FAP mutation suffer from thousands of polyps inside the intestine as early as in their 20s and 30s. Also, those who have untreated FAP are at a much greater risk of developing colorectal cancer. Furthermore, most individuals who have been diagnosed with FAP will have their colons removed to prevent the cancer from forming or spreading. Also, if one of your parents has had FAP, your chances of developing it are 50%.

HNPCC is not as severe as FAP. However, mutations in several genes can lead to both HNPCC as well as several other types of cancers. This is because HNPCC-associated colon cancer is aggressive and readily spreads to surrounding tissues.

These two mutations are not very frequent and having them does not always mean that colon cancer will develop. It just means that individuals who test positive for either of the two will have to undergo more rigorous screening paradigms. In case of either of the two mutations, physicians advise that screening should begin before the age of 40. Furthermore, those who have a strong family history of either HNPCC or FAP-associated colon cancer should definitely get tested for the same mutations.

In addition to a colonoscopy, doctors also rely on blood tests to investigate the possibility of colon cancer by looking at the functions of the kidney as well as the liver. Furthermore, doctors may also look for a chemical that is specifically released by colon cancers, namely carcinoembryonic antigen (CEA). CEA blood levers can help doctors understand colon cancer prognosis as well as whether it is responding to treatments or not.

So, to tie it back to the very beginning, there is not much to remember or know about the genetic underpinnings of colorectal cancer. A few important things must be highlighted when it comes to colorectal cancer. If you have received a positive diagnosis, make sure that all of your family members are informed about your findings as they might be at an increased risk for developing the disorder. This is especially important in cases such as HNPCC and FAP. You need to know that, if you have received genetic testing results that point out you have FAP, your kids have a 50% chance of developing it as well, which is why it is so important to frequently screen for possible colon cancer as well signs and symptoms so that a timely reaction may prevent future problems.

Furthermore, as with all other cancers, it is of utmost importance to realize that stress and anxiety have detrimental effects on disease progression, which is why efforts to lower them should be made around loved ones who have been diagnosed. That should be the primary priority, in addition to remaining informed about all the science, of course. Those who have received a diagnosis should be as open and communicative as possible while realizing that any information they share with their families can ultimately help them as well.

Laura Day