Second Cancers After Colorectal Cancer

Cancer survivors can be affected by a number of health problems, but often a major concern is facing cancer again. Cancer that comes back after treatment is called a recurrence. But some cancer survivors develop a new, unrelated cancer later. This is called a second cancer.

Unfortunately, being treated for colorectal cancer doesn’t mean you can’t get another cancer. People who have had colorectal cancer can still get the same types of cancers that other people get. In fact, they might be at higher risk for certain types of cancer.

People who have had colon cancer can get any type of second cancer, but they have an increased risk of:

• A second colon cancer (This is different from the first cancer coming back.)
• Rectal cancer
• Oral cavity and oropharynx
• Stomach cancer
• Small intestine cancer
• Anal cancer
• Bile duct cancer
• Uterine cancer
• Kidney cancer
• Cancer of the ureter (the tube that connects the kidney to the bladder)

People who have had rectal cancer can get any type of second cancer, but they are at increased risk of:

• Colon cancer
• Small intestine cancer
• Anal cancer
• Lung cancer
• Vaginal cancer
• Kidney cancer

The increased risk with some of these cancers may be due to shared risk factors, such as diet, obesity, and physical activity. Genetics may also be a factor. For example, people with Lynch syndrome (hereditary non-polyposis colorectal cancer or HNPCC) have an increased risk of many of these cancers.

Follow-up after colorectal cancer treatment

After completing treatment for colorectal cancer, you should still see your doctor regularly to look for signs the cancer has come back or spread. See Living as a Colorectal Cancer Survivor for information on the types of tests you might need after treatment.

Survivors of colorectal cancer should also follow the American Cancer Society Guidelines for the Early Detection of Cancer, such as those for breast, cervical, lung, and prostate cancer.

For people who have had colorectal cancer, most experts don’t recommend any additional testing to look for second cancers unless you have symptoms. One possible exception is in women who had colorectal cancer as a result of having Lynch syndrome, as these women are also at increased risk for endometrial and some other cancers. If you have Lynch syndrome or another inherited syndrome, it’s important to talk to your doctor about your risks.

Can I lower my risk of getting a second cancer?

There are steps you can take to lower your risk and stay as healthy as possible. For example, people who have had colorectal cancer should do their best to stay away from tobacco products. Smoking might further increase the risk of some of the second cancers that are more common after colorectal cancer.

To help maintain good health, colorectal cancer survivors should also:

• Get to and stay at a healthy weight.
• Keep physically active, and limit the time you spend sitting or lying down.
• Follow a healthy eating pattern that includes plenty of fruits, vegetables, and whole grains and limits or avoids red and processed meats, sugary drinks, and highly processed foods.
• It's best not to drink alcohol. If you do drink, have no more than 1 drink per day for women or 2 per day for men

These steps may also lower the risk of some other health problems.

See Second Cancers in Adults for more information about causes of second cancers.