Younger people are being diagnosed with colorectal cancer: What to know

A multi-ethnic family with young adults and their parents sitting around a campfire

Nearly every week, a new patient under age 45 is seen with colorectal cancer at The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James).

Cancer of the colon or rectum typically affects older adults, with onset typically occurring in their 60s. Based on the expected ages of colorectal cancer development, screening for the general population isn’t recommended until age 45. Thanks to more colonoscopy screening for those in this recommended age group, the overall rate of colorectal cancer diagnosis across the U.S. population is decreasing.

At the same time, the rate of diagnosis among people under 55 is increasing by 1-2% each year, according to the American Cancer Society.

That overall number is still small, but more people in their 40s, 30s and even 20s are diagnosed with colorectal cancer each year. Those who are diagnosed at a younger age tend to have a more advanced stage of cancer and worse outcomes.

Risk factors for colorectal cancer in younger adults

We don’t know why colorectal cancer is affecting people at a younger age at increasing rates. Researchers are studying the causes and identifying some possible indicators.

Below are some known and unknown causes of colorectal cancer in younger patients:

1 Inherited syndromes

About 30% of those diagnosed with colorectal cancer at a younger age have a hereditary predisposition for cancer. This can include having close relatives diagnosed with colorectal cancer or other forms of cancer, such as uterine, ovarian or stomach cancer. Rare syndromes, like Lynch syndrome, increase a person’s risk of getting cancer. Those with a known hereditary syndrome typically get colonoscopies as often as every year.

2 Inflammatory bowel disease (IBD)

The two main types of IBD are Crohn's disease and ulcerative colitis. Both cause inflammation and irritation of the bowels. This chronic inflammation from IBD increases a patient’s risk of developing colorectal cancer. IBD accounts for about a third of colorectal cases in patients under 45. Patients with IBD should be screened for colorectal cancer every year or every other year. Timing depends on how long one has had the disease.

3 Unknown causes

The most concerning group of those developing colorectal cancer at a younger age is for unknown causes. These patients aren’t screened for cancer until the onset of symptoms, which often only come at a more advanced stage of the cancer.

Possible causes of the increase in colorectal cancer among younger people

Researchers investigating colorectal cancer in younger adults hypothesize that possible causes include some combination of diet, the environment, a lack of activity or changes to the microbiome.

The majority (70%) of colorectal cancers in younger patients tend to occur on the left side of the colon. In those over age 50, colon cancer can occur equally on the right or left side. This could indicate that the cause is something in the microbiome — the bacterial content of the colon. Species located in different areas of the digestive system vary.

Processed foods in the diet and the increase in sedentary behavior that has come with the rise in technology may also be contributors to the rise of colorectal cancer. For each patient, the causes would result from behavior from as much as 20 years in the past. For example, genetic mutations that change colon cells take time to accumulate. If those cells get a survival advantage, then the abnormal cells grow and proliferate over the years.

Signs and symptoms of colorectal cancer

Colorectal cancer may be asymptomatic, meaning it has no symptoms at all. This is why screening across the population is recommended for adults over age 45.

There are four symptoms that may be indicators of colorectal cancer. Speak to your provider if you have any of the following signs:

  1. Blood in the stool
  2. Abdominal pain
  3. Changing bowel habits
  4. Anemia

Other symptoms include a lump in the anal area, fatigue and unexpected weight loss.

Blood in the stool is the most common sign of colorectal cancer. Younger people and even some primary care providers tend to assume blood in the stool is caused by hemorrhoids in younger people. However, no amount of bleeding from the anus is normal. It may be benign, but you need to make sure it's not something more. Speak to your doctor to help you decide whether to get a colonoscopy or further evaluation.

Screening for colorectal cancer

A colonoscopy is a preventive tool used not only to diagnose cancer, but to find any polyp before it becomes cancer. Once you remove a polyp, you don't have that cancer risk anymore.

More people are following screening guidelines by getting colonoscopies and, when necessary, having polyps removed before they become cancerous. In cases when colorectal cancer is identified early through recommended screening, the outcomes are very good.

While not everyone with early-onset colorectal cancer has a family history of cancer, those who do know that cancer runs in the family should be cautious. If one of your close relatives had colorectal cancer, you should get screened 10 years earlier than the age your relative was diagnosed, which may be earlier than age 45. Most important: Definitely don't ignore symptoms.

What to expect with colorectal cancer screening

Colonoscopies are the gold standard for colorectal screening. But any kind of screening is better than none. Stool tests like the mail-in fecal immunochemical test (FIT) or FIT-DNA tests are effective. Note that stool tests can have false positives.

Colonoscopies have some stigma, but most patients find the procedure is not uncomfortable or difficult. Under sedation, you don't feel anything or remember the procedure. What people complain about most is the preparation to clear out the system. As uncomfortable as having multiple bowel movements for hours before the procedure is, having your bowel clean of stool allows the doctor to better see any lesions or polyps.

Unlike mail-in stool tests, a colonoscopy is a preventive and diagnostic procedure. A provider will remove any polyps before they become cancerous. Stool tests must be done every 1-3 years, depending on the test. Colonoscopies may be as infrequent as every 10 years, depending on the patient and the findings.

Better care for colorectal cancer

Colon and rectal cancer can be treated effectively, especially when diagnosed early. Depending on the location of the tumor and the cancer stage, some people need only surgery and monitoring. Others receive a combination of chemotherapy, radiation and surgery.

At the Colorectal Cancer Center at the OSUCCC – James, you can access a group of experts dedicated to colorectal cancer care. This means central scheduling, coordinated appointments across multiple disciplines, expert surgeons and better outcomes.

Patients with early-onset colorectal cancer will also have access to additional support to address the additional stress of a cancer diagnosis at a younger age, such as fertility preservation, emotional distress and financial counseling.

Most colorectal surgeries at The James are minimally invasive, using either laparoscopic or robotic approaches. This means less time in the hospital, less pain and a quicker overall recovery.

With early detection and intervention, patients diagnosed with colorectal cancer can have good outcomes and minimal impact on their overall quality of life.

Accurate, early cancer diagnosis matters

The James Cancer Diagnostic Center gives patients direct, expedited access to diagnostic testing and consultation with Ohio State cancer experts. Think you have cancer?

Schedule an appointment today


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