Colorectal Cancer: A Troubling Trend
More people are being diagnosed with colorectal cancer before 50, the recommended age to start screening.
By Charlotte Huff
Cara Cooper began experiencing fatigue in 2009 when she was 28 years old, first relatively mild but gradually escalating to near-constant exhaustion.
On her doctor’s recommendation, Cooper took vitamin supplements. She began running half and full marathons to bolster her fitness and energy. But her pace, never fast, became slower, and it was a labor just to propel herself forward. “It got to the point that I couldn’t even run down the street,” says the now 34-year-old graphic designer. “It felt like something was sucking the life out of me.”
In 2014, the Melbourne, Florida, resident switched to another medical practice, and the nurse practitioner there ran tests, including an endoscopy for what she speculated might be a bleeding ulcer. It wasn’t until December 2014—after six years of symptoms, two colonoscopies and various detours—that Cooper learned she had metastatic colon cancer that had spread to her liver.
In recent years, studies have offered evidence of a trend that colorectal cancer specialists fret about among themselves: A larger number of young adults like Cooper are appearing in their offices. Although the number of colorectal cancer cases diagnosed before age 50—the typical age to start screening—remains relatively small, younger individuals’ vulnerability to colorectal cancer appears to be increasing. If current trends persist, by 2030 the incidence rate of newly diagnosed patients between ages 20 and 34 will almost double, and among people 35 to 49 it will increase by 46 percent. During the same interval, the incidence rate is projected to decline by more than a third in adults 50 and older, according to data published in the January 2015 JAMA Surgery.
This increase among younger people of a malignancy most frequently diagnosed between ages 65 and 74 raises screening and treatment dilemmas, with more questions than answers. Given the lack of routine screening and perhaps a lack of awareness, colorectal cancer in younger adults might go undetected at earlier, more treatable stages, says Christopher Lieu, a medical oncologist at the University of Colorado Cancer Center in Aurora. Researchers and cancer specialists are also delving into whether these tumors are more aggressive or different in some other way from later-in-life malignancies. Early findings indicate that tumors could be more difficult to treat successfully in younger adults. For example, one small-scale genetic analysis that Lieu was involved in found signs that tumors among adults under 35 might be more resistant to chemotherapy.
Another study led by Lieu, this one published in the Sept. 20, 2014, Journal of Clinical Oncology, and based on data from 20,023 patients with metastatic colorectal cancer enrolled in clinical trials, found that mortality followed a U-shaped curve, with the youngest and oldest patients being most vulnerable. Despite their inherent vitality, the youngest adults faced a 19 percent higher risk of death compared with those in middle age, with the lowest risk among adults in their late 50s. The U-shaped curve began moving up again as patients grew older.
What’s Going On?
The number of early-onset colorectal cancer cases in the JAMA Surgery analysis is still relatively small, with just 3,815 cases, or 1 percent, detected prior to age 35, the group that Cooper falls into. An additional 6.8 percent, or nearly 27,000 adults, were diagnosed between ages 35 and 49. But the study—by looking at 36 years of data (1975-2010) totaling slightly more than 393,000 patients—projected future trends. If current patterns continue, by 2030 slightly more than one in 10 colon cancers and nearly one in four rectal cancers will be diagnosed before age 50, the researchers wrote.