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Original Article |
1 Division of Surgical Oncology, University of Louisville School of Medicine, 315 East Broadway, Room 313, Louisville, Kentucky 40202
2 Department of Medicine and Behavioral Oncology Program, James Graham Brown Cancer Center, University of Louisville School of Medicine, Louisville, Kentucky 40202
3 Department of Psychological and Brain Sciences, University of Louisville School of Medicine, Louisville, Kentucky 40202
4 Abell Research Consulting, Ouray, Colorado 81427
Correspondence: Address correspondence and reprint requests to: Robert C. G. Martin II, MD; E-mail: robert.martin{at}louisville.edu.
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ABSTRACT |
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 TOP ABSTRACT INTRODUCTIONMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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Methods: Participants reviewed a clinical scenario and randomly received one of three ways of describing efficacy of chemotherapy in metastatic colorectal cancer: (1) relative risk reduction, (2) tumor response rate, and (3) median overall survival. They received the same clinical scenario but were presented four treatment options: (1) observation and supportive care, (2) chemotherapy, (3) surgery, and (4) surgery and chemotherapy and the accompanying median overall survival estimate.
Results: Participants included 102 preclinical medical students. In the first scenario, 85% chose chemotherapy in the relative risk reduction group, as did 88% of the tumor response rate group, but significantly fewer participants did so in the median overall survival group (35%; P < .001). In the second scenario, there was a significant difference in treatment preferences, with 4% of participants choosing observation/supportive care. None chose chemotherapy only, 19% chose surgery only, and 77% chose surgery plus chemotherapy (P < .001).
Conclusions: This study demonstrated that different methods of describing oncology treatment outcomes associated with therapy for metastatic colorectal cancer to the liver can have a dramatic effect on patient treatment decisions.
Key Words: Decision analysis • Metastatic colorectal cancer • Chemotherapy • Surgery
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INTRODUCTION |
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TOPABSTRACTINTRODUCTIONMETHODSRESULTSDISCUSSIONCONCLUSIONSREFERENCES |
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Translating scientific data from clinical trials into language appropriate for consulting with patients can be a significant barrier to effective treatment decision-making for patients.3 The primary purpose of this study was first to examine whether the method used to describe the efficacy of chemotherapy influences treatment decision-making by using data from treatment options for metastatic colorectal to the liver. We hypothesized that describing outcomes by using relative risk reduction or tumor-response rates would lead to significantly greater endorsement of chemotherapy than descriptions using the median overall survival benefit. By using hypothetical scenario methodology, the novelty of this study involved randomly assigning participants to receive only one of three different methods of describing the benefits of chemotherapy (relative risk reduction, tumor response rate, or median overall survival). Second, when holding constant the method used to communicate the benefits of treatment for metastatic colorectal cancer (i.e., median overall survival), we sought to determine which treatment options participants would prefer. We hypothesized that multimodality treatment would be selected significantly more often than single-modality treatment (i.e., chemotherapy or surgery) or supportive care only.
Patients with colorectal cancer metastases to the liver often receive conflicting management recommendations based on the use of a single treatment modality (i.e., chemotherapy or surgery). The lack of true consensus in the management of metastatic colorectal metastasis has led to many therapies being considered optimal first-line therapy,4,5 and this creates a complicated treatment decision-making process for patients and physicians. Often, such patients are not offered surgical management of their metastases because of perceived morbidity, lack of efficacy, or other factors. Likewise, such patients may be offered only surgical treatment, without systemic therapy. The decision to undertake one or another of these treatment options is usually based on the bias and experience of the treating physician and may not take into account patient preferences or systematic evaluation of the utility of various treatment options.
Although level I evidence from randomized, controlled trials is available to guide certain aspects of patient care, many issues remain unresolved. Furthermore, such trials do not take into account the effect of age-related conditions, patient preferences, and health-related quality of life considerations. Because of these issues, the optimal management for liver metastases from colorectal cancer has remained controversial. In addition, the data that are being presented to patients regarding the optimal management of colorectal cancer are sometimes biased. Present colorectal cancer guidelines still define the optimal management based on liver metastasis being "resectable".6 Although few would question the virtue of resecting a single, isolated liver metastasis, there is significant controversy regarding the merit of more aggressive surgical or ablative therapy for patients with multiple liver metastases.7–9 With recent advances in surgery and ablative techniques, the number of patients with liver metastases potentially treated by surgical resection, ablation, or both has increased. Thus, with these expanding treatment options, patients with metastatic colorectal cancer must rely even more on their physicians to provide understandable and clear information regarding the risks and benefits of these treatments. Unfortunately, that information may not always be presented in a way that is easiest for patients to process and comprehend.
Several previous studies have explored important oncology treatment decision-making questions by using hypothetical scenarios.10–15 The use of questionnaires incorporating hypothetical treatment scenarios has allowed investigators to examine attitudes toward chemotherapy among physicians, nurses, patients, caregivers, or matched control participants, each providing a unique perspective on the value of adjuvant cancer treatment. These studies have generally shown that individuals diagnosed with cancer are willing to undertake cancer treatment even with very low chances of cure,15 whereas oncology nurses are most commonly the least willing to undergo aggressive treatment.10 Other investigators have explored physician treatment recommendations by using clinical scenarios16 or have investigated attitudes about communicating prognosis and other oncology-relevant information to patients.17,18
Few studies have explicitly examined how quantitative methods used to communicate oncology outcomes to patients may influence treatment decision-making. One previous study found that different methods of communicating numerically equivalent treatment benefit information (e.g., absolute risk reduction, relative risk reduction, and number needed to treat) led to different rates of chemotherapy endorsement among surrogate treatment decision-makers according to hypothetical clinical scenarios.19 The difference in hypothetical treatment decision-making raises questions regarding how other methods of communicating oncology outcomes might also influence patient treatment decision-making. For example, there are many different outcomes of interest when the effects of oncological treatment are evaluated (i.e., median overall survival, disease-free survival, treatment response rates, partial response rates, complete response rates, and others), and each of these could be used to describe the risks and benefits associated with a potential treatment plan. Because manipulating the presentation of this type of treatment information among a sample of individuals diagnosed with cancer would be ethically problematic, we elected to study the effect of presenting different methods of presenting oncology treatment outcomes by using hypothetical clinical vignettes and surrogate decision-makers.
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METHODS |
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The primary component of the questionnaire included a clinical vignette accompanied by information describing treatment options and information regarding the efficacy of the proposed treatment. Estimates of treatment benefits were based on previously published research.20–24 Finally, each participant was asked to make a treatment decision based on the information presented.
Three versions of the questionnaire were distributed randomly to study participants, and each version consisted of two parts (I and II). Part I addressed the primary study question, which involved a comparison of treatment decisions when participants were randomly assigned to receive one of three methods of describing quantitatively equivalent efficacy of chemotherapy in metastatic colorectal cancer to the liver. In part I, approximately one third of participants received the relative risk reduction method, one third received the absolute tumor response rate method, and one third received the median overall survival method of communicating the potential benefit of chemotherapy for metastatic colorectal cancer. All participants received the same clinical vignette in part II, but this aspect of the study required participants to choose from one of the four treatment options (i.e., supportive care only, chemotherapy only, surgery only, or multimodality treatment with surgery and chemotherapy) when only median overall survival benefit information was provided. Participants always completed part I before part II.
Preparation of the Clinical Vignette
The vignette was developed according to relevant clinical scenarios, and the data used to calculate outcomes were derived from established published data.23,25–29 Data for these vignettes were found after an extensive MEDLINE search was performed that used all appropriate key words for metastatic colorectal cancer. All published articles were then reviewed for appropriate data reporting survival by established predictors of outcome in metastatic colorectal cancer. Articles that presented only global overall survival for an entire group of metastatic colorectal patients or response rates could not be used for this study. The articles were then divided into chemotherapy alone, surgery alone, and chemotherapy with surgery. The vignette was derived from the most common presentation of metastatic colorectal cancer reported in these articles: metachronous disease within 5 years from the primary diagnosis with more that one hepatic lesion.
Estimates of the chemotherapy-alone outcomes used data from Rougier et al.22 and Cunningham et al.20 because these were the only two articles that provided overall survival data that were based on established predictors of outcome (i.e., number of hepatic lesions, size of lesions, and so on) in metastatic colorectal cancer. The articles from Scheele et al.23,24 were used because of the high degree of certainty that these patients underwent surgical resection alone.
The vignette asked the participant to assume the following: "Your mother is a 72-year-old woman. You have a good relationship with her and wish her well. Unfortunately, she had a lymph node–positive colon cancer when she was 67 years of age. She had surgery at that time and then had 6 months of chemotherapy. Now, 3
years after her colon surgery, the colon cancer has spread to her liver. There are three tumors in the right side of her liver that have been diagnosed as metastatic colon cancer. Without any further treatment, her median overall survival will be 5.7 months."
The participants were then randomized to one of three treatment efficacy statements that were quantitatively equivalent estimates of outcome and asked whether they would recommend chemotherapy:
The second vignette presented the same clinical scenario. The participants received all four treatment options and were asked to choose a treatment option:
After an initial draft of the clinical vignette, it was reviewed for content and clarity by a surgical oncologist, a medical oncologist, a clinical health psychologist, and a decision scientist. Recommendations offered by these experts were incorporated into the vignette. After this review, the vignettes were analyzed by using readability statistics30 and subsequently modified to an appropriate reading level. Final readability statistics showed that part I had a reading level of 49.6 and a grade-equivalent reading score of 9.8, whereas part II had a reading level of 48.1 and a grade-equivalent reading score of 9.9.
Participants
First- and second-year medical students (preclinical) were offered the opportunity to participate in this research study. Preclinical medical students were selected for this pilot study because the educational level of the students represents a higher-than-average group of participants who should be able to understand the medical scenario presented and the quantitative descriptions of the potential treatment benefits. We reasoned that this educated group likely represented a conservative assessment of the effect of physician communication on patient preferences and treatment decisions.
Measures
Participants were asked to complete sets of questions regarding (1) current mood, (2) attitudes toward cancer treatment, (3) treatment choices, and (4) background characteristics.
Assessment of Mood
Before and immediately after completion of the study vignettes, participants provided a single-item rating of their current mood by using a scale from 0 to 10: "On a scale from 0 (worst mood) to 10 (best mood), how would you rate your current mood?"
Attitudes Toward Cancer Treatment
Perceived tolerability and effectiveness of surgery and chemotherapy for cancer were assessed by using two sets of parallel items. For example, the perceived tolerability of chemotherapy was measured with the following item: "In general, what is your perception of the tolerability of chemotherapy for cancer?" To assess effectiveness, the following item was used: "Regardless of side effects, do you believe surgery for cancer is worthwhile?" Participants provided responses on a scale of 1 (not at all tolerable/worthwhile) to 7 (completely tolerable/worthwhile).
Treatment Choices
Participants were asked to make two treatment choices (i.e., part I and part II). After reading the clinical vignette in part I, participants were asked to report their treatment decision (yes/no) regarding chemotherapy: "Would you advise her to take chemotherapy?" After reading the part II clinical vignette, participants were asked to select which one of the four treatment options they would advise their mother to choose: (1) observation and supportive care, (2) chemotherapy only, (3) surgery only, or (4) combined surgery and chemotherapy.
Background Characteristics
After completing the study vignettes, participants completed questions surveying their sex, race/ethnicity, annual household income range, marital status, current living situation, religious affliation, and hometown population. Participants also responded to questions regarding their personal and family history of cancer and cancer treatments. Participants provided yes or no responses to the following items: (1) personal history of cancer, (2) family history of cancer, (3) personal history of chemotherapy, (4) family history of chemotherapy, (5) personal history of cancer surgery, and (6) family history of cancer surgery.
Statistical Analyses
Descriptive statistics were performed to describe the study population on background variables and attitudes toward treatment. These data were then used to test for any systematic differences among the three randomized groups by using 
2 tests for categorical data and analysis of variance for continuous data. Chi-square tests were used to examine the primary study aim of exploring the influence of the method of communicating treatment outcome information on decisions to endorse chemotherapy and the secondary aim of examining treatment modality preferences when the method of communication is held constant. The statistical methods used to conduct additional analyses included 2 tests, t-tests, and logistic regression.
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RESULTS |
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2 and analysis of variance tests compared baseline and sociodemographic characteristics of participants across groups. Of the 27 baseline and sociodemographic characteristics analyzed, only surgery tolerability demonstrated a statistically significant difference across the groups [F(2,96) = 3.58; P = .032]. By using Bonferroni-corrected pairwise comparisons, post hoc analyses revealed that the relative risk reduction group (mean, 5.64; SD, .82) rated surgery as significantly more tolerable than did the tumor response rate group (mean, 5.00; SD, 1.01), but the median overall survival group (mean, 5.27; SD, 1.06) was not different from either group regarding baseline and sociodemographic characterization. However, this outcome was likely a chance result given the number of 2 and analysis of variance models tested.
Treatment Decisions
Part I
Overall, 69% of participants endorsed chemotherapy after the clinical scenario presented in part I. However, differences emerged among the three groups: 85% of the relative risk reduction group endorsed chemotherapy, and 88% of the tumor response rate group endorsed chemotherapy, but only 34% of the median overall survival group endorsed chemotherapy. A 2 test revealed a statistically significant difference among the groups [2 (n = 98; df = 2) = 27.49; P < .001]. Subsequent Bonferroni-corrected pairwise comparisons showed that the median overall survival group endorsed chemotherapy significantly less often than either the relative risk reduction group [2 (n = 65, df = 1) = 17.25; P < .001] or the tumor response rate group [2 (n = 65, df = 1) = 19.65; P < .001], but there was no difference between the relative risk reduction and tumor response rate groups [2 (n = 66, df = 1) = .13; P = .720].
Part II
Of the 92 participants who provided data for part II, 4% of the participants chose the observation and supportive care option, 19% chose the surgery-only option, 77% chose the surgery plus chemotherapy option, and none of the participants chose the chemotherapy-only option. A 2 test revealed a statistically significant difference in treatment preferences [2 (n = 92, df = 2) = 82.33; P < .001] when the unselected category was dropped from the analyses (chemotherapy only). Subsequent pairwise comparisons showed that combined therapy was selected significantly more often than supportive care [2 (n = 75, df = 1) = 59.85; P < .001] and surgery alone [2 (n = 88, df = 1) = 33.14; P < .001], whereas surgery alone was selected significantly more often than supportive care [2 (n = 21, df = 1) = 8.05; P = .005].
Treatment Decision Correlates
Part I
With regard to part I, none of the sociodemographic variables demonstrated an association with treatment decisions. However, several variables measuring attitudes toward cancer treatment were associated with treatment decisions. Participants who endorsed chemotherapy, regardless of the scenario they received, reported significantly higher perceived tolerability of chemotherapy [t(96) = 2.04; P = .044], higher perceived utility of chemotherapy [t(96) = 3.56; P = .001], and higher perceived utility of surgery [t(96) = 2.14; P = .035].
Part II
Because none of the participants endorsed chemotherapy alone and because only four participants endorsed observation only, analyses compared participants in the surgery plus chemotherapy group versus participants who elected observation alone or surgery alone. With regard to part II, again none of the sociodemographic variables demonstrated an association with the treatment decision. Of the variables depicting attitudes toward treatment, only perceived chemotherapy utility was associated with the treatment decision. Participants who endorsed surgery plus chemotherapy on part II reported a significantly higher perceived utility of chemotherapy [t(90) = 3.03; P = .003; Table 2
].
Multivariate Models of Treatment Decision-Making
Part I
By using the variables that demonstrated a statistically significant relationship with treatment decisions based on bivariate analyses described in the previous section, a logistic regression model was tested to identify independent predictors of treatment decision-making. The logistic regression model for part I included group assignment and ratings of perceived chemotherapy tolerability, chemotherapy utility, and surgery utility. With regard to the group assignment variable, indicator coding was used (i.e., the relative risk reduction and tumor response rate groups were compared against the median overall survival group). As shown in Table 3, the five-variable model was statistically significant [2 (n = 98; df = 5) = 44.20; P < .001]. Of the individual variables, the relative risk reduction group [Wald = 12.68; P < .001] and the tumor response rate group [Wald = 17.06; P < .001] were significantly more likely to choose chemotherapy (14 and 25 times more likely, respectively) than the median overall survival group. Perceived chemotherapy utility [Wald = 5.28; P = .022] also predicted endorsement of chemotherapy, but perceived chemotherapy tolerability [Wald = 2.88; P = .089] and perceived surgery utility [Wald = .20; P = .652] were not independently predictive of treatment decisions.
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2 (n = 90; df = 1) = 8.41; P = .004]. The odds ratio was 2.21, with a 95% confidence interval of 1.26 to 3.86, thus suggesting that participants who rated chemotherapy as more useful were more likely to choose combined treatment (i.e., surgery plus chemotherapy) for metastatic colorectal cancer. |
DISCUSSION |
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Unfortunately, with more options come more confusion, and determining the optimal method of presenting this information to patients in a way that helps them make informed decisions is not a trivial issue. All too often, oncologists (medical, surgical, and radiation) are guilty of deciding what is best for their patient without taking into account the patient’s preferences and quality-of-life issues. This has become especially true in adjuvant chemotherapy31 but is becoming more prevalent in patients who are being asked to decide what form of therapy they should accept for metastatic disease. After all, a balanced presentation of all of the facts and a careful weighing of the risks and benefits is vastly more complicated and time-consuming than simply telling the patient what he or she should decide.31 Furthermore, as oncologists become busier, the time necessary for a long discussion of the pros and cons of all forms of therapy in metastatic colorectal cancer for an individual patient becomes distinctly unattractive.
A recent study by Weinfurt et al.32 highlights the difficulty of communicating quantitative clinical trial outcomes to patients. Patients considering participation in phase I clinical trials were given a hypothetical scenario stating that an experimental therapy would control their cancer in 40% of cases similar to theirs. Subsequently, participants were presented a multiple choice question asking them to interpret the treatment outcome information provided to them in the scenario. Just over two thirds of study participants chose the correct response describing an aggregate probability statement: "For every 100 patients like me, the treatment will work for 40 patients." However, 28% of participants chose incorrect interpretations, consistent with physician confidence—"The doctor is 40% confident that the treatment will control my cancer, or tumor response rates" or "The new treatment will reduce my disease by 40%"—or specifically reported that they did not understand the information. Further analysis showed that several factors, including socioeconomic status and treatment experience, were associated with correct interpretations of the outcome information. The authors suggest that numeracy, an individual’s ability to understand and manipulate quantitative information about uncertain outcomes, is integral to informed decision-making and that it is incumbent on health care providers to identify ways to communicate quantitative information by using metrics that patients can use to make treatment decisions. This is particularly important in the oncology setting, when treatment decisions are commonly made during an acutely stressful period after diagnosis and are accompanied by a patient’s sense that treatment decisions need to be made quickly.
However, the loss of autonomy, which is one of the foundations of the informed consent process, must always be considered during these discussions. Ultimately patients will not be able to provide consent to a treatment unless they have been provided the necessary information in a format that they can fully understand. Exaggerating both the benefits and risks of certain therapies seems to be common. For example, a patient may be told, "You are too old for surgery," or "You should not take chemotherapy because of the side effects that it will cause, such as hair loss, nausea, and diarrhea." One must also take into account the bias in recommending specific treatment modalities according to physician specialty. Not all decisions are based entirely on level I evidence: there are often economic incentives for physicians to recommend one type of treatment over another. For such reasons, the physician may sometimes be less than objective in providing treatment recommendations. When the medical decision-making process is unclear, these types of bias on the part of the physician often may be the deciding factor in the patient’s ultimate choice of treatment.
Clearly, systemic chemotherapy29,33–35 and surgical resection2,8,9,23,36–38 have been demonstrated to benefit patients with hepatic colorectal metastases. Ultimately, the timing and extent of each therapy, unfortunately, has not been clearly defined or agreed on by all oncology specialties.
Thus, the aim of our study was to examine how the method by which the data regarding treatment efficacy are presented to patients affects the acceptance of these treatment options. We presented various treatment options by using common oncology language and demonstrated that the way in which the treatment benefit is described overwhelmingly influences endorsement of certain treatment modalities. Participants were randomized to receive one of three methods of describing the efficacy of chemotherapy in the treatment of metastatic colorectal cancer. The participants were asked to indicate whether they would advise a person in this scenario (their mother) to take the proposed chemotherapy treatment. The methods of describing the efficacy of chemotherapy have been derived directly from numerous chemotherapeutic trials, which have continued to emphasize the overall tumor response rate and relative risk reduction methods of describing the benefit of chemotherapy in the management of this disease.
The results of this study demonstrated significant variability in the acceptance of a certain therapy depending on the method of describing the efficacy of that therapy. In the first scenario, 69% of all participants endorsed some form of chemotherapy in the management of metastatic colorectal cancer to the liver. However, there were significant differences among all three study groups, with a significant increase in the decision to use chemotherapy when the participant was given the scenario that used relative risk reduction (85%) and absolute tumor response rate (88%). This rate decreased significantly when the benefits of chemotherapy were presented as median overall survival time (34%). This indicates a dramatic difference in the acceptance of chemotherapy according to the method of presentation. The participants’ perceived benefits of chemotherapy did not bias this difference in the acceptance of chemotherapy according to the language of presentation.
Finally, in the evaluation of the second scenario, the most significant finding was the lack of any participants choosing chemotherapy alone in the management of colorectal cancer metastatic to the liver. Again, none of the sociodemographic variables demonstrated any significant differences regarding the treatment modality the participants chose.
These results, in both part I and part II, continue to emphasize that the magnitude of benefit for an individual patient is one of the most vital components in the decision-making process. Ideally, the patient should be given the chance to incorporate personal preferences and information about all available treatment options into the decision to accept a specific type of therapy after understanding the pertinent data required to make an informed decision. Obviously, this decision-making process is dependent on the patient’s willingness to be presented the specific prognostic information. In some cases, patients may have very strong, unwavering, preconceived notions about one form of therapy versus another. Thus, even with a long, informed, and open discussion, patients will continue to refuse a certain form of therapy because of perceived toxicity or poor outcome in either a friend or family member.
However, treatment decisions based on patient biases and experience may be more acceptable than treatment decisions made on the basis of biases created by the methods used to communicate treatment efficacy. One potential solution to the bias created by presenting only one aspect or method of treatment efficacy information would be to provide patients with the data from a variety of relevant outcomes (i.e., relative risk reduction, response rate, and median overall survival). However, this approach is not without potential pitfalls. In a study using similar methodology, participants reported significantly greater ratings of confusion when multiple formats or risk and benefit information were presented,39 thus suggesting that more detailed information may require significant clarification to facilitate treatment decision-making.
The limitations of this study obviously stem from the participant population of preclinical medical students in their first and second year of medical training. In addition, these students were given hypothetical scenarios and, thus, may have underestimated the effect of their decision because it was not true to them or to a family member. Nevertheless, the medical student participants should have had an even greater ability than the general population to understand the information presented, as well as the implications of specific therapy decisions. Second, the data used in the scenario constituted the most reliable data presented in a patient with specific metastatic colorectal risk factors. Because of the paucity of specific data presented in most chemotherapeutic reports of survival by well-established risk factors, the best estimates of treatment efficacy available in the literature had to be used. Obviously, new information and new treatments would most certainly influence the validity and generalizability of the results. Finally, it is not likely that a single scenario can adequately represent the complex array of factors that can influence a treatment decision in clinical practice, yet this methodology provides an opportunity to explore the effect of an important issue (communicating outcomes data) that affects nearly every oncology consultation that involves the selection of treatments.
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CONCLUSIONS |
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Received for publication March 21, 2005. Accepted for publication November 8, 2005.
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