Second Cancers

rmcc doctor talking with patient

At Rocky Mountain Cancer Centers, we know that becoming a cancer survivor is a huge accomplishment. However, it’s important to understand that being cancer-free doesn’t guarantee that you won’t ever develop a second type of cancer. This doesn’t mean you should live your life in fear. You should, however, continue to be watchful over your health, which includes screenings and regular checkups.

But what are second cancers? Why do they happen? Can they be avoided? The following information covers these factors and more. 

What are Second Cancers?  

According to the American Cancer Society, second cancers occur when a previous cancer patient develops a new, unrelated cancer. A second cancer is not the same as a recurrent cancer, which describes the return of the first cancer you received treatment for.  

Although second cancers are uncommon, they do occur. In fact, approximately one in every six people who are diagnosed with cancer has had a different kind of cancer in the past

Can Cancer Treatment Affect the Risks of Developing a Second Cancer? What About Other Risks?  

When Was Initial Cancer Treatment Given?

Unfortunately, there are certain cancer treatments that can increase the risk of developing a second cancer later in life. Patients who underwent treatment in their younger years (as children, teens, or young adults) are at an even higher risk for developing a second cancer.

Does Radiation Therapy Cause Second Cancers?

Out of all the types of cancer treatment, radiation therapy is noted as one potential cause of a second cancer, with leukemia being the most common type of cancer brought on by prior radiation exposure. At the time of the radiation treatments, your oncology team determined that the need for results outweighed the risks and that thoroughly treating the first type of cancer was a necessity. It’s important to remember that not everyone who undergoes radiation will develop a second cancer. Several factors increase the likelihood of a second cancer from radiation including:

  • How much bone matter was exposed to radiation
  • The amount of radiation that reached the bone marrow
  • The radiation dose rate (how much was given, how long it took to administer, the duration of the treatment)

What About Chemotherapy? Does It Cause Second Cancers?

Instances of second cancers have also been linked to certain types of chemotherapy. In fact, chemo is widely regarded as a greater risk factor for developing leukemia as a second cancer than radiation therapy is. Drugs that may increase the risk of a survivor developing a second cancer include alkylating agents, platinum-based drugs, topoisomerase II inhibitors, and other targeted therapy drugs.

Other Risk Factors for Developing Second Cancers

Doctors believe that there are some risk factors that increase the likelihood of developing second cancers. Many of these are the same as the risk factors that can increase your risk of developing a first type of cancer. These can include: 

  • Genetics
  • Smoking
  • Drinking too much alcohol
  • Being overweight or obese
  • Unhealthy diet
  • Environmental toxins

Can the Risk of Developing Second Cancer Be Lowered?

It depends. No cancer is fully preventable, but removing as many risk factors as you can from your day-to-day life can improve your chances of fending off a second cancer. 

Lifestyle Changes

If you smoke, consider quitting right away and limit how much alcohol you consume. Focus on eating a balanced diet and exercising regularly. Making changes such as these can point you in the right direction when it comes to lowering your chances of developing a second cancer. 

Screenings & Checkups

Attending all of your follow-up appointments with your RMCC oncology team should be a priority. With that said, it’s also important to see your primary care physician. Be sure to schedule yearly checkups with your PCP so he or she can monitor other aspects of your health including blood pressure, blood sugar, mammograms, skin checks for skin cancer, colorectal cancer screenings, and/or other screenings that may be recommended based on your medical history.

Even though you might not be able to significantly lower your risk of developing a second cancer, you can increase the likelihood that it'll be detected early. We encourage you to stay alert, being watchful for new signs and symptoms. You can also talk with your oncologist about the steps you can take to keep your risk down.