Preparing for Long-Term and Late Effects of Cancer

February 19, 2019

When deciding on cancer treatment, patients should also consider the risk of future health problems.

FOR MOST PATIENTS, the actual treatment for cancer will be short-lived. Generally, the longer the cancer experience—from the first suspicious symptom to the final treatment appointment—the longer the time needed to recover from the physical and emotional ripple effects.

The post-treatment picture can vary substantially, depending on the type of cancer and treatment, and the long-term prognosis. For example, some cancer types might require ongoing treatment or follow-up surgery, such as reconstructive procedures, leaving the patient cancer-free, but not free of cancer’s effects.

Some patients have lingering physical and emotional effects that began during treatment and continue afterward. Called long-term effects, these can include pain, neuropathy (nerve damage), anxiety, sleep disturbances, cognitive dysfunction and fatigue. These long-term effects often resolve over time.

Others might have issues related to cancer or its treatment that emerge months or years after treatment has ended. These so-called late effects include such issues as secondary cancers, infertility and heart, bone or lung problems.

While both adult and pediatric cancer survivors experience late effects, more is known about survivors of pediatric cancer because researchers have gathered long-term survival data for those cancer types for more than 20 years. Research into late effects experienced by adult survivors is complicated by the fact that as people age, they develop other medical problems, or comorbidities, making it more difficult to determine if the problems are related to prior cancer treatment, aging or an interaction between the two.

Secondary Cancers

For example, one class of medications, known as anthracyclines, can cause damage to the heart. The damage is dose-dependent, meaning the more of a drug a patient has, the more likely he or she will have a problem. Radiation presents another heart risk, since beams aimed at the chest to fight lymphoma, breast or other cancers can also reach the heart and lungs. Radiation can weaken or scar the heart muscle or damage its valves. It also can accelerate coronary artery disease, creating rough spots in the lining of the arteries where fatty plaque can accumulate. If cancer returns, it is considered a recurrence of the primary cancer. When a survivor receives a diagnosis of a new primary, it might not be connected to treatment for the first diagnosis, or it might be a secondary cancer—one caused (or whose risk could have been increased) by treatment for the initial cancer.

A second cancer can occur for a variety of reasons, most unrelated to past cancer treatment. For example, it is well known that breast cancer survivors with BRCA mutations are at higher risk for ovarian cancer, and current or former smokers who have survived other cancers have an increased risk of lung cancer.

CANCER PATIENTS OFTEN HAVE OTHER ILLNESSES that can impact treatment decision making, some of which are considered here.

  • Cancer patients receiving treatment for depression must be aware that some antidepressants can decrease the effectiveness of cancer drugs.
  • Surgery might not be an option for lung cancer patients with emphysema since impaired lung function can cause complications.
  • Hormonal therapies can increase the rate of bone loss, so patients with osteoporosis could be at increased risk for fractures and additional loss of bone mass.
  • Certain drugs can cause nerve damage, so patients with diabetes, a disease that can also cause nerve damage, are at greater risk for neuropathy.
  • Cancer patients with heart problems might not be able to receive anthracyclines or some targeted agents because of the risk of heart damage.

Researchers know that many patients who received a secondary cancer diagnosis experienced high doses of radiation to certain areas of the body or particular types of chemotherapy. For example, radiation is known to be a risk factor for breast cancer in women who had radiation to the chest area.

Researchers have also concluded that some late effects tend to occur within a specific time period. For example, leukemia and other blood cancers caused by some chemotherapy drugs tend to develop within several years of treatment. By contrast, the risk of developing a new solid tumor continues to increase even 10 years after therapy.