Colon Cancer Screening: Who Should Get Screened and How

Cancer is regarded as a silent killer as it mostly shows symptoms in its advanced stages when it may be difficult to treat.

This is why the medical community strongly recommends regular cancer screenings for high-risk individuals, even if they don’t have any symptoms. This type of proactive healthcare helps to catch the disease early before it metastasizes or spreads to other parts of the body.

The need for screening is particularly emphasized in the case of colon cancer, which is often asymptomatic and a major contributor to global mortality. Early cancer diagnosis through regular screenings will lead to early treatment, which can greatly improve the survival rate.

How Common Is Colon Cancer?

The odds of having colon cancer after age 50 years are approximately 1 out of 20 (5%).

Based on a recent SEER database analysis, colon cancer appears to be increasing among younger people. There’s an approximately 51% increase in colon cancer before the age of 50 in the last two decades compared to the previous two decades. (1)

Based on this analysis, the American Cancer Society has advised changing the guidelines to getting started for colon cancer screening at age 45, instead of the previous recommendation of starting at age 50 years.

Screening with a colonoscopy can prevent colon cancer close to 90%. (2)

Where Is Colon Cancer Pain Usually Felt?

Colon cancer may not cause pain in the early stages. However, if pain is present, its location depends on the site of cancer. The pain can be felt anywhere in the abdomen.

Signs and Symptoms of Colon Cancer

Colon cancer may not cause any symptoms early on and the symptoms could be quite nonspecific. However, the main symptoms of colon cancer include:

Do Colon Cancer Symptoms Differ in Males and Females?

No, colon cancer symptoms are similar in men and women, although the prevalence of cancer is slightly higher in men than in women. (3)

Different Methods of Colon Cancer Screening

The methods of colon cancer screening can be divided into noninvasive and invasive methods.

1. Noninvasive methods

Noninvasive methods are stool-based tests to check traces of blood, such as the hemoccult test, fecal immunochemical test (FIT), and Cologuard test, which combine FIT with some markers of tumor cells.

The FIT test is positive in about 70% of patients with colon cancer, and Cologuard is positive in about 92%. (4) However, false positive and false negative test results may occur. This means many of the patients who test positive in noninvasive tests may not have cancer, and sometimes if the test results are negative, the cancer may have been missed.

2. Invasive methods

Invasive tests for cancer include endoscopies, such as a flexible sigmoidoscopy (evaluation of the left side of the colon) or colonoscopy (examining the entire length of the colon). The gold standard of colon cancer screening is colonoscopy.

Detecting Colon Cancer at Home

Noninvasive colon cancer stool screening tests such as the FIT test and Cologuard can be performed at home. However, the collected stool specimen still needs to be sent to the laboratory for analysis.

Reasons to Get Screened for Colon Cancer

Colon cancer is the second leading cause of cancer death in the United States. It is estimated that over 50,000 patients die every year from colon cancer. (5) Thus, colon cancer screening can end up saving your life.

The survival rate for colon cancer depends on the stage of diagnosis:

• Advanced-stage cancer is associated with poor survival.
• If the cancer is found in the early stage (stage I or II), the 5-year survival rate is approximately 95%.
• For stage III cancer (metastatic to lymph nodes), the 5-year survival rate drops to 70%.
• For stage IV cancer (distant metastasis), the 5-year survival rate is only 5%. (5)

Therefore, screening for cancer is the most important thing to improve cancer-related deaths. Screening for cancer with hopes of finding the cancer at an early stage and treating it is the best way to cure cancer.

People Who Should Get Screened for Colon Cancer

Most healthcare systems, including the healthcare law in the United States, promote colon cancer screening. The risk of colon cancer is very high in both men and women of advancing age.

Based on the new guidelines from the American Cancer Society, average-risk men and women should start colon cancer screening at age 45 years. (6)

Early colon cancer screening is recommended for people who have a family history of colon polyps, colon cancer, and hereditary colon cancer syndromes or a personal history of inflammatory bowel disease such as ulcerative colitis or Crohn’s disease.

Individuals with a family history of colon cancer are usually recommended to start colon cancer screening 10 years before their earliest family member had a cancer diagnosis.

Those with a family history of hereditary colon cancer syndromes might need to start colon cancer screening in their 20s. Those who have inflammatory bowel disease are usually recommended to undergo a colonoscopy every 1–2 years after having 8–10 years of disease duration.

Risk Factors Associated With Colon Cancer

The risk factors for colon cancer can be divided into two types: nonmodifiable risk factors and modifiable risk factors.

• Nonmodifiable risk factors are those you can’t change, such as aging and genetic factors, including a family history of colon polyps, colon cancer, and hereditary colon cancer syndromes and a personal history of inflammatory bowel disease.
• Modifiable risk factors are those you can change, which include avoiding high-fat, processed foods, red meat, smoked food. Eating healthy, such as consuming a low-fat diet, less processed foods, and more fruits and vegetables, decreases the risk of cancer.

Difference Between Hemorrhoids and Colon Cancer

Hemorrhoids usually cause symptoms of anal discomfort and rectal bleeding. Both of these symptoms can also be present in colon cancer if it’s near the anus.

Therefore, people who have symptoms suggestive of hemorrhoids and are in the colon cancer screening age must submit for screening to determine the cause of the symptoms, whether hemorrhoids or colon cancer.

Final Word

Colon cancer is a very common cancer and a major cause of cancer-related deaths in the United States and Western world. Many patients may not have any symptoms before the cancer is at an advanced stage.

Therefore, individuals who are at risk of colon cancer, especially those aged above 45 years, and have a family history of colon cancer and colon polyps should undergo a colonoscopy to find the colon cancer at an early stage, which is associated with good survival rates.

Additionally, undergoing a colonoscopy with detection of colon polyps and removal of colon polyps can prevent the development of colon cancer.