Carol Carr showed all the signs of colorectal cancer seven years ago, but doctors thought the 44-year-old Maryland woman was too young to have the disease and never tested her for it.
They said her diarrhea, vomiting, cramping, iron deficiency and extreme fatigue were more likely caused by the flu, anxiety and even a brain disorder.
Carr got so sick she had to stop working. When she finally saw a specialist who ordered a colonoscopy, she was suffering from Stage II colorectal cancer. The test found a mass that blocked most of her colon and had grown through her intestinal wall.
Misdiagnoses like Carr's are becoming more common as a disease historically associated with people older than 50 is increasingly affecting a younger population. While overall rates of colorectal cancer have been dropping since the 1980s, cases in people under age 50 have been slowly, but steadily rising, research has found. The biggest increases come among people in their 40s.
Overall rates have been declining by about 3 percent per year in men and by 2.3 percent per year in women, according to the American Cancer Society. But colorectal cancer rates in people ages 18 to 49 increased 2.1 percent between 1998 and 2007.
While younger patients still make up a sliver of people who get the cancer, researchers and scientists are paying more attention before the problem worsens. It was a topic of discussion at a recent conference for the Colon Cancer Alliance in Baltimore.
Dr. Y. Nancy You, a Texas oncologist who spoke at the conference, said that most research on colorectal cancer skews toward older people. "It's hard to know whether the current research is really applicable to the younger population," she said.
Nobody really knows why the cancer is increasing in younger people. Doctors believe lifestyle — including poor eating habits, lack of exercise and obesity — is part of the problem. Some of the answer may also lie in genetics and environmental factors.
Better screening and testing have helped over time to curb the disease, which is the third most commonly diagnosed cancer. Using colonoscopy, doctors are able to detect and remove polyps, saclike growths on the colon wall, before they develop into cancer. But guidelines generally call for screening people older than 50 and suggest younger people get tested only if they are showing signs and have a family history.
Carr is now 51 and cancer-free, but she remembers the frustration of being misdiagnosed. The sales engineer had three-fourths of her colon removed.
When it is finally diagnosed, the cancer in younger patients has usually progressed to a more advanced stage, making it more complicated and costly to treat, doctors said.