Incidence of Rectal Cancer in Young Adults Has Increased
Age is a known risk factor for rectal cancer for those who are over 40 years old. A new study published early online in journal Cancer reveals an increase of rectal cancer cases in adults under the age of 40 over the past several decades.
According to the National Cancer Institute, in the United States an estimated 142,570 men and women (72,090 men and 70,480 women) will be diagnosed with and 51,370 men and women will die of cancer of the colon and rectum in 2010.
Rectal cancer stats are lower in younger people
Rectal cancer is considered to be rare among young individuals in the United States. Approximately 0.1% of all the colon and rectal cancers were diagnosed in people under age 20; 1.1% between 20 and 34; and 3.8% between 35 and 44.
Joshua Meyer, MD, a radiation oncologist currently at Fox Chase Cancer Center, led a team that analyzed trends in rectal cancer incidence in the United States compared with colon cancer trends. This work was done will he was at the New York-Presbyterian Hospital/Weill Cornell Medical Center in New York City.
The researchers conducted a retrospective study using data from the Surveillance Epidemiology and End Results (SEER) cancer registry. They identified 7,661 colon and rectal cancer patients under age 40 years between 1973 and 2005. The researchers then calculated the change in incidence over time for colon and rectal cancers.
Overall rates of colon and of rectal cancer were low during the years of the study (1.11 cases and 0.42 cases per 100,000, respectively). While colon cancer rates remained essentially flat in individuals under age 40 years in recent decades, rectal cancer rates have been increasing since 1984. Specifically, between 1984 and 2005, the rate of rectal cancer diagnosis rose 3.8% per year.
The rectum is the last 6 inches of the digestive system between the large intestine and the anus. Signs and symptoms of rectal cancer can include a change in bowel habits or blood in the stool.
"We suggest that in young people presenting with rectal bleeding or other common signs of rectal cancer, endoscopic evaluation should be considered in order to rule out a malignancy," said Dr. Meyer. "This is in contrast to what is frequently done, which is to attribute these findings to hemorrhoids. More frequent endoscopic evaluation may be able to decrease the documented delay in diagnosis among young people," he explained. Because the overall incidence of rectal cancer is relatively low, the authors do not advocate for a change in screening guidelines.
"Increasing incidence of rectal cancer in patients under age 40: an analysis of the Surveillance, Epidemiology, and End Results database," Joshua E. Meyer, Tarun Narang, Felice H. Schnoll-Sussman, Mark B. Pochapin, Paul J. Christos, David L. Sherr. Cancer; Published Online: August 23, 2010 (DOI: 10.1002/cncr.25432).
National Cancer Institute