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Journal of Clinical Oncology, Vol 25, No 29 (October 10), 2007: pp. 4628-4634 © 2007 American Society of Clinical Oncology. DOI: 10.1200/JCO.2006.09.6255 Women's Interest in Gene Expression Analysis for Breast Cancer Recurrence Risk
From the University of North Carolina Lineberger Comprehensive Cancer Center; School of Public Health; and Department of Psychology, University of North Carolina at Chapel Hill, Chapel Hill, NC Address reprint requests to Suzanne C. O'Neill, PhD, Social and Behavioral Research Branch, NHGRI/NIH, Building 31, B1B36B, Bethesda, MD 20892; e-mail: oneills{at}mail.nih.gov
Purpose Genomic and other technologies are improving the accuracy with which clinicians can estimate risk for recurrence (RFR) of breast cancer and make judgments about potential benefits of chemotherapy. Little is known of how patients will respond to genomic RFR testing or interact with their physicians to make informed decisions regarding treatment. We assessed interest in genomic RFR testing and patient preferences for incorporating results into treatment decision making. Patients and Methods One hundred thirty-nine women previously treated for early-stage breast cancer completed surveys that presented hypothetical scenarios reflecting different test outcomes and potential decisions. We assessed women's attitudes toward RFR testing, how results would affect their choices about adjuvant treatment, and potential concerns about and perceived benefits of testing. Results The majority of participants said they would "definitely" want to be tested (76%), receive their results (87%), and discuss these results with their physicians. They were willing to pay, on average, $997 for testing. Those who expressed more concerns about testing were less interested in testing and in incorporating results into treatment decision making. Participants were more likely to want chemotherapy when presented with high-risk results and would worry more about those results. They were least likely to trust and most likely to express potential anticipated regret in response to intermediate RFR results. Conclusion Participants expressed strong interest in testing. Although these decisions were sensitive to RFR, participants complex reactions to intermediate RFR suggest care is needed when communicating such results.
In 2007, an estimated 178,480 women in the United States will be diagnosed with breast cancer.1 Although effective treatments for breast cancer are increasingly available,2 decisions about which treatment options to pursue are complex3 and often produce anxiety.4 Currently, estimates of risk for recurrence (RFR) of breast cancer and benefits of adjuvant therapy are based on clinical characteristics, such as disease stage, tumor pathology, estrogen and progesterone receptor status, human epidermal growth factor (HER-2) status, and patients overall health.5,6 Recent studies suggest that gene expression analysis of breast cancer tumors can categorize RFR,7 aid prognosis,8-13 and predict response to chemotherapy.7,14 Gene expression analysis offers the potential to identify women who are at greatest RFR and therefore are likely to receive the greatest benefit from chemotherapy.3,7 Ultimately, genomic RFR testing could reduce the need for additional treatments for some women with early-stage, node-negative, and estrogen- and progesterone-positive breast cancers. Two clinical trials15,16 will provide a better understanding of the potential clinical impact of these methods. Few studies have assessed either physicians or patients interest in genomic RFR testing or how it may affect decision making regarding chemotherapy. Cognitive and affective factors—such as perceived benefits of treatment, concerns about the toxicities of treatment, and related worry—are known to influence adjuvant treatment decision making by patients.17 Similar factors could affect response to RFR testing. Studying potential responses to clinical innovations before they become part of routine practice allows for the identification of important patient or physician concerns.18-21 Therefore, our study assessed breast cancer patients attitudes toward genomic RFR testing, interest in testing had it been available when they were diagnosed, and potential response to the receipt of test results. We also examined how varying the magnitude of RFR would influence patients preferences for chemotherapy and their anticipated emotional responses.
Participants Study methods are described elsewhere.22 In brief, eligible patients met the following criteria: English-speaking, previously diagnosed with stage I/II primary breast cancer, completed surgery, and either had not received or had completed adjuvant chemotherapy. Patients were ineligible if they had a life-threatening comorbid disease, second primary cancer, cancer recurrence or metastasis, or history of serious psychiatric illness. In 2005, eligible patients were mailed invitation letters 2 weeks before their appointments and were approached by trained research assistants in the University of North Carolina Breast Clinic (Chapel Hill, NC). Participants were read, and were provided a paper copy of, a brief description of genomic RFR testing (Appendix, online only), and completed self-administered questionnaires. Study protocol and materials were approved by the University of North Carolina institutional review board.
Measures Being tested. Two items assessed interest in testing: willingness to be tested if it were free, accompanied by a 5-point scale labeled "definitely would not" to "definitely would," and willingness to pay out of pocket for testing, accompanied by a 6-point scale labeled, "Nothing," "$1 to 99," "$100 to 499," "$500 to 999," "$1,000 to 2,499," and "$2,500 or more." We coded responses to the latter with the value of each category's midpoint, with zero as the lowest response and $2,500 as the highest response.
Attitudes about testing.
We adapted 11 items from the literature to assess participants attitudes toward genomic RFR testing,20,21,25 accompanied by a 5-point scale labeled "strongly disagree" to "strongly agree." We obtained a two-factor solution using principal axis factoring and created two scales by averaging these items. The first scale, "concerns," had seven items that shared the common theme of concerns about testing and how it would affect treatment ( Preferences about decision making. Two items assessed participants preferred decision-making style regarding involvement in the decision to be tested and in how the test results would influence treatment. Each was accompanied by a response scale adapted from the Control Preferences Scale.26 Consistent with common practice,27,28 responses were recoded as a "passive," "active," or "shared" decision-making styles. Using test results. Three items assessed participants preferences for incorporating RFR test results into treatment planning. Three items assessed whether participants would want to know RFR test results, whether they would want to discuss the results with their doctors, and whether they would want the results incorporated in treatment decision making, accompanied by a 5-point scale labeled from "definitely would not" to "definitely would." We used hypothetical scenarios to assess potential responses to testing, similar to what was done in early studies undertaken to understand the potential uptake of and response to cancer susceptibility testing.21-23 All participants viewed scenarios that described hypothetical test results yielding high and then low RFR. For each vignette, we assessed participants interest in chemotherapy given the results alone and in combination with the advice of their physician to get chemotherapy, accompanied by 5-point scales from "definitely would not" to "definitely would." We assessed trust in test results and worry and regret about results in response to scenarios describing high, low, and then intermediate (ie, "in-between") RFR results, accompanied by 5-point scales labeled "not at all" to "extremely."
Statistical Analyses
We present our findings in separate sections on participants characteristics, perceived concerns and benefits, interest in testing, preferred decision-making role, potential response to test results, and the impact of RFR on treatment decisions. Overall, we found very strong interest in genomic RFR testing. However, we also identified some concerns about trust in testing and test results.
Study Participants
Concerns About and Perceived Benefits of RFR Testing Participants rated the potential benefits of the genomic RFR test higher than they did potential concerns (3.13 v 1.33, respectively, on a 5-point scale; t = 18.97; P < .001). Participants, on average, strongly disagreed with concerns about testing, and they were more balanced in their response to potential benefits, tending neither to agree nor disagree with these statements. Concerns and perceived benefits were uncorrelated (r = –.13; P = .13), suggesting that they were distinct constructs. Women with limited finances expressed significantly greater concerns, as did those without college degrees (Table 2).
Interest in Testing The majority of women stated they would "definitely" want to be tested (76%). Responses were categorized as "definitely" and "other" for statistical analyses. "Definitely" wanting to be tested was inversely related to age and concerns about testing. Women who reported more perceived benefits of and fewer concerns about testing were more likely to say that they would "definitely" want to be tested (Table 3).
Women said they were willing to pay, on average, $997 (95% CI, $840 to $1,155) out of pocket for testing. Those who had heard of genomic RFR testing before the study were willing to pay more for testing (Table 2).
Preferred Decision-Making Role
Potential Use of Test Results
Impact of Risk for Recurrence Results on Response to Testing
RFR magnitude affected anticipated emotional responses (Fig 2). Participants worry would increase as a function of RFR [F(2,129) = 80.19; P < .001]. They would regret an intermediate RFR result the most [F(2,129) = 11.13; P < .001], with those expressing more concerns about testing anticipating greater regret [F(2,129) = 3.90; P = .02]. They also trusted an intermediate RFR result the least [F(2,129) = 24.37; P < .001]. Women who perceived more benefits were more trusting of test results [F(2,129) = 4.36; P = .02], as were those who had received chemotherapy [F(2,129) = 4.27; P = .02] and those with sufficient finances [F(2,129) = 4.75; P = .01].
We considered that participants with high RFR at their initial diagnosis might express systematically different responses to testing and to decisions about treatment. Sensitivity analyses indicated that participants own RFR was not a significant covariate or interaction term in any analysis.
Most participants indicated that they would have been interested in genomic RFR testing at the time they were treated for early-stage breast cancer had it been available. Most women preferred an active role in decision making about treatment and would have wanted the results incorporated into treatment planning. Women said they would be willing to pay approximately $1,000 for genomic RFR testing. Currently, the out-of-pocket costs for OncotypeDx (Genomic Health, Redwood City, CA) range from a few dollars for some insured women up to $3,287 for some uninsured women.29,30 Although the highest option on our scale assessing willingness to pay was less than some women might pay (an artifact of the test's cost being unknown when we planned our study), only a handful of women used this highest option. This gives us confidence that $1,000 offers a realistic early estimate of women's willingness to pay for the test, an amount that is lower than some women would, in practice, pay out of pocket. Participants expectations regarding chemotherapy preferences, worry and regret about test results, and trust in test results were all sensitive to RFR magnitude. This is important, because one potential benefit of this technology is the ability to more accurately predict recurrence and tailor adjuvant care for some women.3 Previous studies indicate that many early-stage breast cancer patients prefer chemotherapy even if it will offer little benefit.31,32 For the potential benefits of RFR testing to be fully realized, patients and their physicians must recognize that not all patients require adjuvant chemotherapy. Patients, in turn, must be willing to forgo chemotherapy based on the combination of their physicians recommendations, RFR test results, and other relevant clinical information. Patient's chemotherapy preferences were sensitive to low and high RFR magnitudes, even when a physician counseled them to have chemotherapy. Some of the scenarios that we presented are likely to happen frequently in practice, such as a physician's recommendation to have chemotherapy in response to a high RFR result. Other scenarios are less likely, such as a recommendation to have chemotherapy in response to a low RFR result. In practice, few physicians would advocate chemotherapy in light of indicators that a woman's RFR was low. We used this scenario to elicit participants reactions to a situation presenting conflicting information rather than to suggest that it mirrored common clinical practice. Our results underscore the comparable weight that participants placed on their physicians recommendations and the importance of patient education regarding how clinicians incorporate genomic RFR information into treatment decision making. Indeed, the value placed on testing by the physician and how this is conveyed will likely be critical to patients decision-making processes. Although it is promising that participants hypothetical decisions about chemotherapy were sensitive to RFR and physician recommendations, participants trusted high RFR results most and intermediate RFR results least. Although the clinical significance of these findings on trust is unclear given their small magnitude, one potential explanation is that a high RFR result would suggest a clearer path of action (chemotherapy), whereas a result indicating an intermediate RFR would involve greater ambiguity, thus changing the acceptability of the result.33 Medical decision making in response to results conferring an intermediate RFR, along with results that are not concordant with clinical parameters, would convey the greatest uncertainty and require the most deliberation. Our results suggest that patients may have the greatest difficulty in accepting the validity of such results, mirroring findings regarding the difficulties inherent in understanding, accepting and processing clinical risk information that confers higher than expected levels of ambiguity.34-38 Participants concerns about testing were unrelated to their treatment decisions in the context of a hypothetical scenario about chemotherapy. In contrast, participants with more concerns reported lower willingness to be tested and to have the results used to guide treatment decisions. One explanation for these apparently conflicting results is that some participants were unable to integrate their reservations about the test into their hypothetical treatment decisions. It remains possible that patient concerns may affect treatment decisions in a clinical setting. This study has several limitations, including a cross-sectional design and a sample limited to women who were post-treatment for breast cancer and who received follow-up care at one clinical center. Only 60% of the women approached during the study were included in our analysis. The combination of these factors suggests that our results may not reflect the attitudes of all women who will qualify for RFR testing. Because we conducted this study as RFR testing was moving into clinical use, we could not interview similar groups of women who had received genomic RFR testing. Responses of actual patients and clinicians may depart from our findings. Also, hypothetical scenarios cannot fully capture the complexities of decision making before the commencement of adjuvant treatment. The scenarios did not specify a timeframe for recurrence, and we did not counterbalance to distribute any potential order effects across the scenarios. However, the employment of hypothetical scenarios allowed us to systematically examine participants responses under different conditions relevant to decision making about adjuvant care.39-41 Unlike people with strong family histories of cancer proactively seeking cancer susceptibility testing42 (which they can do without referral from their health care provider), breast cancer RFR testing likely will be integrated into the routine care of women with early-stage, node-negative, estrogen- and progesterone-positive breast cancers. Just as early studies examining potential response to cancer susceptibility testing employed hypothetical scenarios, our research took this approach to allow us to obtain critical early information on women's preferences. Although we have since learned that those studies overestimated uptake20,21,43 and emotional distress,21,44 they were an important step in understanding how best to communicate with patients about testing. Several studies have examined adjuvant treatment preferences32,45,46 and their relation to RFR was assessed using standard clinical indicators.40 To our knowledge, our study is the first to demonstrate patients interest in genomic RFR testing and how these results might influence decisions about adjuvant care. Overall, our results indicate that patients will welcome this information, that they prefer to be involved in how their test results will guide treatment choices, and that they will be sensitive to results when making decisions about their treatment. These findings have important implications for communicating with patients newly diagnosed with breast cancer as RFR testing transitions into clinical care.15,16
The author(s) indicated no potential conflicts of interest.
Conception and design: Suzanne C. O'Neill, Noel T. Brewer, Sarah E. Lillie, Edward F. Morrill, Lisa A. Carey, Barbara K. Rimer Financial support: Suzanne C. O'Neill, Noel T. Brewer Administrative support: Noel T. Brewer, Sarah E. Lillie Provision of study materials or patients: Noel T. Brewer, E. Claire Dees, Lisa A. Carey, Barbara K. Rimer Collection and assembly of data: Suzanne C. O'Neill, Noel T. Brewer, Sarah E. Lillie, E. Claire Dees Data analysis and interpretation: Suzanne C. O'Neill, Noel T. Brewer, Edward F. Morrill Manuscript writing: Suzanne C. O'Neill, Noel T. Brewer, Edward F. Morrill, E. Claire Dees, Lisa A. Carey, Barbara K. Rimer Final approval of manuscript: Suzanne C. O'Neill, Noel T. Brewer, Sarah E. Lillie, Edward F. Morrill, E. Claire Dees, Lisa A. Carey, Barbara K. Rimer
Information About the Recurrence Risk Test Administered to Study Participants The new test is called the Recurrence Risk Test. Here is how a woman uses the test. She gets a test after she has surgery to remove her cancer. The test tells the chances that her cancer will recur or come back. The woman and her doctor talk about her test results and her other medical information. Then they decide if she needs more treatment. Here is how the test works. The test looks at genes in the cancer that make it recur. These genes may be different from ones that control breast cancer being passed onto one's children. The test doesn't require extra surgery because it is done using some of the cancer that was already removed. The test has a few benefits. First of all, the test results can help a woman choose the most effective treatment. For example, a woman with a high chance of recurrence might want chemotherapy to improve her chances of being cured. On the other hand, a woman with a low chance of her cancer recurring may not need chemotherapy. She could avoid unneeded treatment and side effects. A second benefit is that the test can give more accurate results than the medical tests we use today. So a woman can choose her treatment with more confidence. On the downside, tests don't always give the right answer. This means some women will get the wrong information about their chances. Another problem is that the test may be expensive and may not be paid for by health insurance.
We thank the physicians and nurses of the University of North Carolina Breast Clinic for their assistance during the study. We especially thank Beth Fogel, RN, for her help accruing patients. Most importantly, we thank the women who participated in this study.
Supported by grants from the American Cancer Society (MRSG-06-259-01-CPPB), the National Cancer Institute (R25 CA57726), and the UNC Lineberger Comprehensive Cancer Center. Authors disclosures of potential conflicts of interest and author contributions are found at the end of this article.
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Copyright © 2007 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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