Colon and rectal cancer tests should start at age 45

Colorectal cancer is the second-leading cause of cancer death in the United States, most frequently diagnosed among adults over 65. To catch those typically slow-growing malignancies early, when they can often be cured, most doctors’ groups recommend colorectal cancer screening starting at age 50.

The American Cancer Society said that most people should start screening tests for colon and rectal cancers at age 45, rather than waiting for age 50.

The group said the initial test does not have to be a colonoscopy, a procedure that typically requires a day off from work and an often-unpleasant bowel cleansing routine. Instead, it could be one of several other tests, including home stool tests available by prescription.

But the shift by the cancer society is based on new information about the rise in colon and rectal cancer among younger adults, said Andrew Wolf, an associate professor of medicine at the University of Virginia. He led the group writing the new recommendations.

Colon and rectal cancers have increased 51% among adults under age 50 since 1994, the cancer society said. “We don’t know why it’s going on,” Wolf said, noting that suspects include obesity and poor diet. “But it’s increasingly clear that it is happening.”