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Genetic Testing Intensifies Research On Psychological Impact of Cancer

Barbara Boughton

Scientists know that there are real psychological effects to being at high risk for cancer and receiving news of genetic test results, whether positive or negative. As a result, the availability of genetic testing has intensified research into the psychology of cancer.

According to experts in the field, patients’ feelings about being at risk for cancer heavily influence their decisions about whether or not to have genetic testing.

"Most people at risk for cancer are quite resilient and have little trouble functioning day to day," says Michael Stefanek, Ph.D., chief of the Basic Biobehavioral Research Branch at the National Cancer Institute. "But certainly they do have cancer-specific worries and fears, even very intrusive thoughts about getting cancer. They report having fearful thoughts pop into their heads more often than they would like."

Researchers who studied psychological distress among 200 colorectal cancer patients undergoing testing for hereditary nonpolyposis colon cancer found a subset of individuals who exhibited symptoms of psychological distress. They also found that these individuals may need more intensive follow-up to facilitate adjustment to genetic test results.

"The people who were more distressed also tended to be more anxious about getting genetic test results, and had higher levels of a desire to know," said Ellen R. Gritz, M.D., Ph.D., one of the investigators and professor and chair of the Department of Behavioral Science at the University of Texas M. D. Anderson Cancer Center, Houston.



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Dr. Ellen R. Gritz

 
An individual’s difficulty in anticipating the emotional impact of receiving test results also seems to contribute to distress levels. A group of investigators who followed 65 individuals going through genetic testing for either p53 cancer syndrome or BRCA1 mutations found that most people correctly estimated their initial emotional reactions to test results. However, cancer patients who were carriers of a BRCA1 mutation frequently underestimated their emotional response to getting a positive result.

Patients who underestimated their reactions and experienced higher levels of psychological symptoms when receiving their result remained distressed 6 months after the test. "A positive test result can shake a person’s world in many ways," said Andrea Patenaude, Ph.D., director of psycho-oncology research at Dana-Farber Cancer Institute, Boston, and one of the co-authors of the study. "For cancer patients, who know what having cancer is like, a positive result can be even more scary."

Research also suggests that the test results of family members can also influence an individual’s level of distress. They may feel most distressed if they are the first family member to be tested, and hear their results. Those who test negative may also feel "guilt" if their siblings are carriers, and these feelings can often affect family dynamics for the worse. "Often a person’s reaction to their own test results is a function of the test results of their brothers and sisters," said Robert Croyle, Ph.D., associate director for behavioral research at NCI.

Cancer-related fears and distress can persuade people to take widely varying approaches to genetic testing. In an article in a 1999 Journal of the National Cancer Institute Monograph, Croyle and Caryn Lerman, Ph.D., of Georgetown University, found that among people who believed they could take action to reduce their risk, fears about cancer motivated genetic testing. Yet among those who suffered from more global anxiety or depression or a perceived lack of control over their cancer risk, distress about inheriting cancer led individuals to avoid testing.

For many people, such distress and fears about cancer can be misplaced. Croyle and Lerman contended that most people with a family history of cancer greatly overestimate their personal cancer risk. And these exaggerated perceptions, as well as the individual’s distress about his or her risk, strongly influence decisions about whether to undergo genetic testing.

Knowledge about the risks and benefits of genetic testing seems to help. As well as motivating people to obtain test results, it can prevent distress afterward. In an earlier study, Lerman found that women who had the most knowledge of BRCA1 testing were more likely to choose to learn their genotype results. "Those who tested negative for a BRCA1 alteration were relieved, and those who tested positive did not exhibit increases in psychological distress," Lerman said.

Many people at risk, however, are unaware of genetic testing, now done mainly in research settings. In a study of more than 1,000 women at risk for breast cancer published last June, only 64% of the women had heard of genetic breast cancer testing beforehand, and most had less than optimal knowledge about it. Yet 72% of these high-risk women said they would undergo genetic tests if they became available.

As tests move from research centers to physicians’ offices in the future, researchers worry that this lack of knowledge—and inadequate preparation for testing—may become more of a problem. As the tests become more widespread and less likely to be handled by genetic specialists, experts fear counseling may not be of high enough quality to prepare people for the emotions associated with testing.

With some patients experiencing a high amount of distress from genetic test results and no genetic cure available, the question is whether such tests are truly worthwhile. Yet researchers agree that the tests do have benefits because they can enable some patients to increase surveillance testing and take preventive steps.

For example, patients with FAP genes may also be encouraged to have frequent colonoscopies. Kathryn Kash, Ph.D., director of psychological services at Beth Israel Medical Center, said that with genetic testing, patients can make informed decisions about their health care.

That is why many researchers continue to advocate high-quality, targeted counseling and education for people at high risk for cancer. "People who have a family history of cancer should be getting good counseling about the risks of genetic testing, and how to make choices about preventive strategies," Kash said. "We should be sending reassuring messages to those who are at risk."



             
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