To our knowledge, there is no consensus regarding the optimal treatment strategy for localized prostate cancer. Newly diagnosed patients faced with selecting a treatment must consider a myriad of factors, including limited evidence regarding treatment efficacy; the risk of potential side effects; recommendations from physicians, family members, or friends; economic consequences; prior medical care experiences; and emotional feelings about a cancer diagnosis, as well as many other influencing factors. Previous studies have found considerable variation in the treatments that patients receive, and notable differences in the types of therapies received between white and black men. The anxiety patients feel at the time of diagnosis, the complexity of issues surrounding prostate cancer treatment, and the lack of consensus regarding management all contribute to a decision-making process that varies from person to person.
Many studies have examined different aspects of the treatment decision-making process. The methods employed include retrospective surveys, qualitative focus groups, decision aid development and evaluation projects, and patient and physician shared decision-making studies. The goal of this review was to synthesize the information from these studies to identify universal themes that emerge regarding the motivations for why patients select one treatment strategy over another. The treatment strategies included in the current review primarily were watchful waiting, radical prostatectomy, external beam radiation therapy, and brachytherapy.
First, we reviewed the published studies to identify those issues patients consider to be important in making their treatment decisions. This part of the review focused on identifying the key issues that men report basing their decisions on, and how men weigh these issues when making a decision. The second part of the review then explored the published studies to understand why these issues are important to patients. We identified information from the published studies that indicated the reasons and sources of values that patients place on particular outcomes. This aspect of the review highlights potentially overlooked aspects of decision making that are important for understanding whether the variation in treatment patterns is a result of patient values and preferences or whether the variation is due to other factors. A final goal of this review was to identify gaps in the knowledge base regarding decision making for localized prostate cancer.
MATERIALS AND METHODS
We conducted an English language review of published reports concerning the treatment decision-making process for localized prostate cancer. Databases used for the search included PubMed, PSYCHInfo, and the Cumulative Index to Nursing & Allied Health Literature (CINAHL®). We limited our search to the period between January 1990 and November 2004. Key words included prostate, decision making, patient preferences, shared decision making, and decision aids. Additional articles were identified through hand searching the reference sections of relevant studies and using the cross-reference “related articles” feature of PubMed. We selected articles based on guidelines established by the Cochrane Library and the Centre for Reviews and Dissemination, and the Metaanalysis of Observational Studies in Epidemiology (MOOSE) group.1, 2 We restricted our review to original, peer-reviewed studies that focused on the decision-making process. We excluded studies of men with advanced prostate cancer, studies that focused on outcomes after treatment, and studies of decision making for prostate-specific antigen (PSA) screening. Although there are several articles providing physician perspectives concerning treatment decision making, we excluded commentaries that did not provide specific information regarding the direct experience of patients.
Ideally, one would compare the treatment decisions observed for patients with recommendations from guidelines outlining optimal treatment choice(s), given clinical factors. When deviation from the recommendations was observed, one would search for factors that led to suboptimal treatment choices. Unfortunately, the lack of high-quality evidence from prospective controlled trials comparing treatments for localized prostate cancer leaves investigators without a “gold standard” therapy or therapies against which to measure actual choices. Therefore, the treatment choices for localized prostate cancer that are made must be evaluated in a broader context that includes connecting patients' decisions to criteria such as whether patients have access to all relevant information, and whether the information is presented in such a way that their true treatment preferences are revealed and realized. Without a gold standard, we must evaluate what factors are driving patients to make the decisions they do. The first part of our review summarized the findings of studies that described what issues patients consider and how patients attempt to weigh multiple factors in their treatment decisions. For the second part of our review, we summarized findings from studies that described how framing and interpretation influences affect the conclusions that patients make concerning outcome factors and treatment.
We identified 69 articles that met our criteria. These included 16 survey studies,3–18 16 studies aimed at designing and exploring decision aids,19–34 16 focus group studies regarding treatment decision making,35–50 10 studies examining shared decision making between patients and physicians,51–60 6 studies exploring health state preferences associated with treatment decision making,61–66 and 5 review articles related to treatment decision making.67–71
What Issues Are Important?
Few men with localized prostate cancer reported making their treatment decision on the basis of a single or even a few issues. When men are asked to recall the reasons for selecting a treatment, they often provide unique and personal reasons, with few common issues emerging as being important to the majority of patients. For example, in 1 study of 60 patients, 18 different attributes of treatment were identified as being the “most important.”26
Cancer eradication is nearly every patient's initial concern, and for many men it remains the primary issue in their treatment decision. Patients and their families have repeatedly reported spending considerable time and energy researching treatment efficacy.20, 42, 45, 70 Feldman-Stewart et al.59 found that 18 of the top 20 questions reported by newly diagnosed patients were about cancer control.
As men adjust to their diagnosis and learn about the efficacy of treatment options, cancer control remains the primary factor for some, whereas for other men other issues emerge.66 In the largest study we reviewed, which involved 1000 patients, approximately 42% of patients defined an effective treatment as one that extended expected survival or delayed disease progression, whereas 45% indicated that effectiveness meant preservation of quality of life (QOL).5 This is in contrast to physicians, 90% of whom defined effectiveness as extending expected survival. In another study, fewer than 20% of patients ranked either “effect of treatment on length of life” or “chances of dying of cancer” as 1 of the 4 most important factors in making a decision.26 In 1 study of health state preferences, 2 of 5 men were unconditionally willing to risk side effects for any potential gain in life expectancy.64 These studies suggest that there is substantial variation in the significance that patients place on cancer eradication, and that treatment efficacy means more than “control” of the tumor for many patients.
Concerns regarding cancer eradication appear to correlate directly with aggressiveness of therapy, with radical prostatectomy being the choice preferred by the majority of patients who focus on cancer control. These patients typically convey a belief that surgery offers the best chance of control. For example, interviews with 140 patients found that even when the treatment options were presented in terms of equivalent survival and the complications of surgery were emphasized, many patients preferred surgical treatment to watchful waiting.66
Patients report a wide range when asked directly about how much they relied on evidence of treatment efficacy to guide their decision. One study reported that only 26% of patients cited a treatment's record in improving survival as important to their treatment choice,10 whereas another study found that 98% of prostatectomy patients and 50% of brachytherapy patients indicated they selected their treatment on the basis of evidence that it was the best procedure to cure their cancer.9 These results demonstrate that there is considerable variation in how patients interpret the limited cancer control efficacy information currently available. This gap between beliefs regarding efficacy and clinical evidence also appears to be widest for men for whom radical prostatectomy was preferred. Diefenbach et al.7 reported that patients with localized disease who chose surgery considered their disease to be significantly more serious than those selecting external beam radiation therapy or brachytherapy. It is noteworthy that the men selecting surgery in this study population had considerably lower PSA levels on average than men selecting radiation therapy. The authors of 1 study examining the low use of watchful waiting commented that few men appeared to be aware that treatment did not guarantee improved survival.38
Although some men emphasize cancer control more than others in making their treatment decision, control is an important issue for nearly all patients, even those who forgo immediate therapy. Interviews with 8 men who delayed conventional treatment in favor of complementary and alternative medicine revealed a strong desire to take control over all aspects of their cancer care. In addition to reporting a desire to take control of their disease, all these men also underwent frequent PSA testing after diagnosis.47
These studies demonstrate that although cancer eradication is at the forefront of nearly every patient's mind, there is considerable variation in the importance that men place on cancer control when making their decision.
Treatment-related side effects and their impact on health-related QOL
In addition to cancer eradication, another extremely important area for many patients is how treatment may impact their QOL through possible side effects that include incontinence and impotence. The potential side effects of treatment and their impact on QOL have been studied exhaustively. A recent report indicated that more than 800 articles concerning QOL after prostate cancer treatment were available in the medical literature.72 Some experts have concluded that the most important factor in determining an individual's optimal treatment strategy should be the patient's individual preference in association with possible side effects and complications of treatment.73, 74
Incontinence appears to substantively influence the treatment decisions of approximately half of patients; impotence is usually reported to be less important than incontinence (Fig. 1). When patients were asked to rank all the factors that were important to their decision, urinary function and bowel function were the only 2 factors found to be important to greater than 50% of patients.26 This study also found that fewer than 20% of men reported sexual functioning as 1 of the top 3 attributes important to their decision, although 32% mentioned that it was important. A different study found that 49% of men were concerned about incontinence and 38% were concerned about impotence.10 There was variation in the significance men placed on incontinence and impotence in the decision process depending on the treatment options they were considering, with considerably less importance placed on impotence and urinary incontinence among men considering radiation therapy.3
To our knowledge, there is limited information available regarding how men balance side effects in making their treatment decision. For example, although preservation of sexual function was rated as very important by 90% of men age younger than 60 years, and 79% of men age 75 years and older, in a separate question only 3% of these same men indicated that “having few side effects” was the most important consideration in initiating therapy.5 Fear of side effects was also stated by only 3% of men in a study in North Carolina, in which the majority of patients were black.8 Srirangam et al.45 reported that although 55% of spouses reported that side effects were important, only 6% indicated that side effects were deciding factors. One study comparing surgery and brachytherapy reported that 25% of patients chose between these 2 options based on the side effect profile.9 In addition, although Holmboe and Concato10 found that 49% of patients were concerned with incontinence and 38% were concerned with impotence, only 13% reported weighing the risks and benefits of treatment. These studies demonstrate the apparent disconnect between patients' stated importance of side effects and the role that they actually play in reaching the final treatment decision.
In addition to incontinence and impotence, other side effects and treatment complications also are commonly stated as important factors in making the treatment decision. Fear of surgical complications was emphasized by some men who selected watchful waiting.7 A different study found that complications due to surgery were of concern to 12% of patients when considering surgery.3 A belief that radiation is harmful rather than therapeutic was offered by some men who selected surgery.44 When considering radiation therapy, 21% of men indicated concern about skin burns.3 Long recovery times were cited by 17% of patients.10 For a small percentage of men, issues such as fear of surgery or radiation appeared to be the primary factor in their decision regarding treatment.
Costs and other outcomes
To our knowledge, few studies to date have examined the influence of costs on treatment decision making, and the studies that did examine this issue suggest that neither direct nor indirect costs are important when making the decision for the majority of patients. Out-of-pocket costs were stated to be the most important consideration in initiating therapy for only 2% of men in North Carolina,8 3% in the survey by Crawford et al.,5 and 5% in the survey by Holmboe and Concato.10 In ranking 93 questions that men had regarding treatment, the question concerning costs was ranked 92nd.23 In a different study, the effect of treatment on ability to work was ranked as the first or second most important factor by 4% of patients.26 One study observed that brachytherapy was popular among working patients and their partners.45 In another study, men who did not choose radiation indicated that they perceived radiation therapy to be time-consuming and disruptive to their daily schedule.44 One of the reasons that patients cited for selecting external beam radiation therapy or brachytherapy instead of surgery was that they believed it was more convenient than surgery.7
Framing and Interpreting Influences in Prostate Cancer Decision Making
The second part of our review examined the decision-making literature to understand some of the reasons why patients place the values they do on many of the key issues related to prostate cancer treatment. Specifically, we examined the literature to identify how prostate cancer treatment decision making is influenced by framing factors, nonsystematic processing of medical information,75 and patient biases resulting from previous beliefs regarding cancer and health.
The physician recommendation has been reported by several studies to play a large role in influencing a patient's decision. In studies that asked men to report the major influencing factor in their decision, the physician was identified by 57% of patients in 1 study,8 by 65% of patients in a second study,9 and by 70% of patients in a third study.14 Holmboe and Concato10 noted that 30% of men explicitly mentioned physician recommendation as being important to their decision. In evaluating the influence of information sources, 51% of men indicated that information from their physician was most important in reaching a decision, noting that 75% of these men obtained information from 2 or 3 physicians.7
Considerable attention has been given to shared decision making between patient and physician in the process of selecting a treatment choice. Early studies have suggested that men take a passive role in the process, relying on the physician to select treatment.20 O'Rouke70 has suggested that relying on the physician may in fact be an “active” decision on behalf of a patient. Some men report feeling that the treatment decision is a technical matter requiring the expertise and experience of the physician.39 Recent studies have found evidence that patients are becoming more active in the decision-making process and are relying less on the recommendations by physicians.3, 21, 69, 70, 76, 77 In a updated study by Davison and Degner,56 only 32% of men wanted their physician to make the final decision, compared with 58% from a study conducted 5 years earlier20 using the same questionnaire. Holmboe and Concato10 found that 70% of newly diagnosed patients cited factors other than physician recommendation as a main factor in their choice of treatment, although 74% recalled receiving a treatment recommendation from at least 1 physician.
The role of the physician recommendation has received considerable attention in prostate cancer decision making due to the widely recognized preferences held by each physician specialty. As might be expected, opinions regarding the optimal treatment for localized prostate cancer vary among urologists, radiation oncologists, oncologists, and general practitioners. Urologists nearly universally indicate that surgery is the optimal treatment strategy, and radiation oncologists similarly indicate that radiation therapy is optimal.78 In the U.S., because urologists perform biopsies for patients who are suspected of having prostate cancer, they tend to be the first physician to discuss the diagnosis with the patient. The studies we reviewed reported substantial variation in the proportion of men who see both urologists and radiation oncologists, and in the rates of second opinions. Several studies noted that many patients rely primarily on the opinion of an urologist. One large retrospective survey study of 1000 patients found that 38% of patients believed it was important to obtain information from a nonurologist physician5; a similar study found that 37% of patients reported seeking an opinion from an additional physician, although 75% of men still selected the first treatment recommended to them.14 However, others have found that patients do not rely on the urologist's recommendation. In 1 study, 70% of men who received a recommendation for surgery selected another therapy.10 Other studies have found that approximately two-thirds45 and three-quarters7 of patients, respectively, see at least 2 physicians.
Given the bias in treatment preferences by specialty, it is likely there is discordance in which treatment options are provided to patients and the strength of individual recommendations associated with each option. To our knowledge, few studies to date have attempted to examine this bias by quantifying which treatment options were discussed with which men. These studies have focused mainly on discussions of watchful waiting, finding that watchful waiting may be selectively discussed among patients.8 When men were specifically questioned regarding preferences for “watchful waiting” in focus groups, they commonly reported not being presented with the option by their physician and many believed that watchful waiting was the equivalent of doing nothing.44 We did not identify studies that directly assessed how strongly treatment options were recommended. Further understanding of the extent to which treatment options are or are not provided, along with qualitative and quantitative explorations of how each is emphasized, may help to explain the wide variety in treatments that men receive.
Several studies have investigated possible reasons why side effects are found to be relatively noninfluential in the decision-making process. Patients may intentionally or unintentionally choose to minimize the issue of side effects, but another explanation is that side effect profiles are not well understood by patients. One reason patients may not understand side effect issues is that they do not receive accurate information; another reason may be that the information is presented in a way that is difficult for them to understand. O'Rouke44 found that patients reported the potential side effects of surgery and radiation therapy to be the same. This lack of clarity may be due to physicians not thoroughly discussing the risks of side effects for each treatment modality. In 1 study, only 16% of patients recalled discussing side effects with their physician, whereas 100% of the physicians surveyed reported that they had thoroughly discussed the side effects associated with each treatment option with all their patients.5, 17
Influence of spouses and family members
Spouses and family members may have a significant influence on a patient's ultimate decision regarding treatment. Spouses frequently initiate and take a lead role in seeking out additional information.41–43, 45 Although their goals for therapy are likely similar to those of the patients in many ways, studies suggest that their understanding of and preferences for various aspects of therapy differ from the patients themselves. For example, the importance of side effects has been shown to be different for men compared with their spouses. Spouses were less concerned than patients about side effects and their potential impact on QOL, especially the importance of sexual function and sexuality.21, 34, 44, 45, 64 When spouses were asked to report the factors that influenced their input regarding their husband's treatment, total eradication of cancer was commonly stated as the most important factor and occasionally the only important factor.38, 45, 64
To our knowledge, the degree to which partners influence the final decision is unclear. In some studies, patients have reported feeling considerable pressure from their spouses and family members to aggressively treat their cancer.10, 38 One focus group found that a spouse's influence on the final decision was quite small and that in the end spouses felt they should leave the final decision to their husband. This was in contrast to their initial beliefs, in which spouses thought they would want to be more influential in the final decision.45 An educational intervention found that before the intervention, 13% of patients thought they would base their decision on their family's influence. However, after an educational intervention, only 5% indicated their family would likely be a strong factor in their decision.31
Other studies have found that although partners were very involved in obtaining information and supporting the patient, they ultimately had relatively little influence on the patient's final decision regarding treatment. Often, other individuals such as friends or business colleagues who previously were diagnosed with prostate cancer were found to have a stronger influence than spouses.9, 36 In 1 study, patients who selected surgery commonly stated that the main reason they chose surgery was because someone they knew had undergone surgery.7
Racial, cultural and socioeconomic factors
Although variations in the types of treatment men receive has been demonstrated repeatedly based on race, with black men reportedly receiving less aggressive therapy,79–83 to our knowledge there has been little examination of the role of individual preferences in explaining this variation. One study found that the treatment options discussed by physicians vary by patient race, with black men being presented with fewer options.8 We found little research addressing whether there are differences in the decision-making priorities of minority patients compared with white men. A small study found that the main focus for 6 of 7 black men was the spread of the tumor, compared with only 5 of 24 white men.36 This same study also found that these same 6 black men reported not reading any additional written information, whereas all of the white men reported examining additional written information. One investigator pointed out that most of the decision aid tools appear to have been developed through surveys of white males treated in large academic centers.4
Some studies suggest that the educational level of the patient can play a significant role in treatment decision making,5, 84 whereas other studies have not found treatment decisions to vary by educational level.12, 14 A study comparing men who chose either surgery or brachytherapy found no differences with regard to socioeconomic factors.9 Many studies have reported that men with higher educational levels are better able to synthesize and cope with the complex information provided by physicians and educational resources, and studies also have reported that these men are more active in the decision-making process.5, 8, 15, 16 In a study focusing on a population of men with low socioeconomic status, Kim et al.58 found that low literacy levels made shared decision-making programs less effective. A low level of education also was found in some studies to be associated with greater difficulty in completing health state utility assessments.62 One study demonstrated that patients with lower educational levels more frequently experienced regret about their treatment decision than men with more education.11 Another study noted that physicians more commonly discussed watchful waiting with more educated patients, whereas surgery and brachytherapy were discussed more often with higher income patients.8 Higher income also has been shown to be associated with a greater use of complimentary and alternative therapies.16 These findings suggest that there may be a complicated pathway in which sociodemographic factors frame and influence information. Physicians may discuss fewer options or go into less detail regarding the options they do discuss with some men.
Psychologic factors such as fear and anxiety may influence treatment decisions. A recent review of instruments used to assess anxiety among men diagnosed with prostate cancer examined 29 studies.85 Although several of these studies focused on the role anxiety played in screening decisions, to our knowledge none directly examined the role of anxiety in the treatment decision-making process. Further evaluation of the role of psychologic influences in making treatment decisions is needed.
In the absence of a gold standard of therapy for prostate cancer, an ideal decision-making process would provide patients with access to all relevant information, and the information would be presented in such a way that their true treatment preferences are realized. Ideally, the variation observed in the treatments that men select should be due to differences in preferences from well informed patients. Our review of the decision-making literature suggests that there is considerable variation in treatment decisions that does not appear to be truly reflective of patient preferences, but rather is attributable to differences in both the content and the methods by which patients receive information. One might expect biases from the people and sources prostate cancer patients rely on for their information. Nevertheless, patients appear to have significant limitations in their ability to identify biased information, as well as their ability to weigh complex information regarding the outcomes that are important to them. Below, we will discuss some of these biases and offer a few suggestions on how they might be addressed.
The perceptions of treatment efficacy related to cancer control far outweigh available supporting evidence, and the majority of patients appear to select a prostate cancer treatment based primarily on its perceived ability to control the tumor. There may be several reasons for the misperception regarding the impact of treatment on cancer control. One factor may be the ubiquity of terminology such as “the war on cancer,” and the health care system's emphasis on battling or combating the tumor. Men also may be influenced by high-profile success stories of patients. Importantly, the physicians many men rely on may intentionally or unintentionally be providing falsely optimistic information regarding the impact of therapy on cancer eradication and cancer-specific survival.
We did not find any discussion in the literature concerning whether patients were able to distinguish between high-quality and low-quality evidence. We suspect that patients are far less discriminating in their evaluation of evidence supporting particular treatment options, particularly in relation to watchful waiting, than health professionals. We suggest that evaluations of patients' ability to grade evidence are needed, as well as interventions designed to improve their ability to distinguish helpful information from useless or confusing information.
Several studies noted that although patients were concerned about side effects when asked, the issue ultimately had little influence on the treatment decisions of the majority of men. The literature suggests that side effects are not emphasized (and in some cases not even mentioned) by physicians, and when information is presented it is done so in a way that is confusing or misinterpreted by patients. Because of this problem, patients may often ignore or discount the information they do receive. A recent review of decision aids and other sources of information available to patients by Fagerlin et al. has shown that most materials 1) contain biases toward active treatment, 2) minimize the role of watchful waiting, and 3) underestimate the likelihood and impact of side effects.69 We agree with the authors of this study, who concluded that a new generation of materials is needed.69
There is a general lack of information regarding how a patient's personal values shape and influence decision making. A recent article suggested that patients can take multiple approaches to processing data, occasionally focusing only on a subset of the available information, or sometimes systematically processing and thoroughly analyzing individual information to make a decision.86 The lack of information regarding how patients with prostate cancer use different types of input in the process of choosing a treatment and how nonsystematic processing of information influences their choice is beginning to be noticed.76 However, more research is needed to determine how personal values shape perceptions, biases, and the integration of information regarding treatment options.
Partners and family members can be expected to play some role in a patient's decision making regarding treatment, although to our knowledge there is conflicting literature regarding whether their role is substantial or modest. More research is needed in this area, including the sources family members turn to for information and the interactions they have with physicians and other health care providers.
To our knowledge, there is little information available regarding the role of the health care system in patient decision making. Perhaps this is because most studies are conducted in large, urban, academic medical center settings. Future studies need to explore the influence of health care systems on decision making (eg, how information and coverage policies from health insurers and areas of expertise within delivery systems influence patient choices).
Race, culture, and socioeconomic status have been shown to play an important role in the choice of treatment, with several patterns of care studies finding that less aggressive treatment is more frequent among blacks and men with lower income or educational levels.79–83 However, the majority of studies of socioeconomic variables use imprecise measures. One study that focused on poverty found that prostatectomy rates were similar among blacks and whites once poverty was considered.86 To our knowledge, in general there have been few published studies of prostate cancer decision making in minority and socially disadvantaged populations. Given the prevalence of prostate cancer among blacks and its ubiquity across all social strata, studies attempting to understand the decision-making process in minority and lower socioeconomic level populations are greatly needed.
One limitation of the current review is that the available studies represented select samples of patients, typically from large academic clinics, and that minority patients were underrepresented. In addition, it was not possible to make regional comparisons because of difficulties comparing individual studies. Future research should strive for a more balanced representation of all the settings in which men receive treatment. Many of the findings are from Canadian and European patients, which may not be generalizable to U.S. patients due to differences in insurance, clinical settings, information sources, and available treatments. Another limitation of the literature in this area is that nearly all the studies were retrospective. Many of the findings may represent patients' justification of the treatment that was selected and not the thoughts that men were having while they were trying to decide on treatment. Furthermore, the variability in the findings we observed in the reviewed studies may be due to variations in the quality of the studies. There appeared to be little consistency in how questions were asked of patients across the studies.
We recommend future prospective studies aimed at examining how patient values evolve throughout the period of time from their first being diagnosed with prostate cancer until the completion of treatment. In these studies, it is important to not only identify those factors that influence patient decisions, but also to assess the issues that frame and influence those factors. Such knowledge may help health care providers identify and address issues that patients are undervaluing or overvaluing when considering treatment options for their prostate cancer.
Although we do not know whether the considerable variation noted in treatment, particularly the lower rate of aggressive therapy among black patients, is contributing to poorer prostate cancer mortality rates, understanding the source of the treatment variations is an important priority. Until evidence becomes available regarding the efficacy of available treatment options, decision making will remain a process of carefully balancing uncertain outcomes. This review suggests that a patient's perception of control is a primary reason for selecting one therapy over another. A patient's strength of perception originates from a wide variety of sources, due in part to the lack of clear medical evidence, and often is inconsistent with other values held by the patient. The lack of consistency we observed suggests that considerable progress is needed in helping patients fully understand how to balance the complex issues surrounding making a decision regarding prostate cancer treatment.