IN THE NEWS: Hypnosis for Cancer Care
Hypnosis for Cancer Care: Over 200 Years Young
Section 1: Overview of Hypnosis
What is hypnosis?
Surprisingly, this is a more complex question than one might think. There have been a number of published definitions of hypnosis over the years, each of which differs in terms of what it includes and from what theoretical orientation it is derived. Yet there are commonalities across definitions (see Table 1). The two commonalities across most definitions are that the participants in the hypnosis encounter are identified as a hypnotist and a client, and that suggestions are a key ingredient in hypnosis. Although these definitions provided an important foundation for the field, they have failed to include two additional clinical factors which are important to the success of therapeutic or medical hypnosis – client consent, and the therapist describing the technique as intended to be helpful. We believe that for both practical and ethical reasons, hypnosis clients must agree (consent) to participate in any therapeutic hypnosis intervention. Hypnosis does not work if the client is unwilling or resistant to participate. It is important for clients receiving hypnosis in the heath care setting for some type of medical or psychological issue to understand that hypnosis is a psychotherapeutic technique. We let clients know that we intend for hypnosis to help improve their quality of life, not to be a parlor trick or an experiment. To incorporate all of these factors, in 2010 we published an updated definition (see Table 1). We have found that this definition is easy for clients to understand, and helps them feel comfortable with participating in hypnosis.
Section 2: Hypnosis in Cancer Care
One of the earliest documented uses of hypnosis with a cancer patient was as anesthesia for breast cancer surgery. In 1829, M. le Docteur Chapelain used hypnosis (then referred to as mesmerism) over a period of several months to relieve the suffering of Madame Plantin, who had an ulcerated cancer of the right breast with massive enlargement of the right axillary lymph nodes. On April 1, 1829, in Paris, Chapelain used hypnosis as an anesthetic during mastectomy and axillary node dissection. This was prior to the introduction of modern anesthesia techniques. During the operation, the patient was calm and evidenced good pain control 16. In the past two centuries, research on hypnosis has continued to support the efficacy of hypnosis in the cancer setting as an adjunct to modern care (e.g., analgesics). That is, hypnosis is typically used in conjunction with modern medical approaches, as it is the rare cancer patient who can achieve complete symptom and side effect control during major medical and surgical procedures with hypnosis alone.
Below, we provide an overview of the research literature on the use of hypnosis in cancer prevention, diagnosis, treatment, and survivorship. Where meta-analysis or systematic reviews exist, we describe those results rather than individual studies. Where no meta-analysis or systematic reviews exist, we provide a brief description of our literature search strategy for identifying studies, references in the area, and conclusions drawn from the work.
There is strong evidence that an individual’s cancer risk can be significantly reduced by avoiding tobacco, exercising, practicing healthy dietary habits, and participating in cancer screening. The American Cancer Society estimates that this year alone 173,200 of cancer deaths in the United States will be caused by tobacco use, and that one-third of the 577,190 cancer deaths expected to occur in 2012 will be attributed to poor nutrition, physical inactivity, overweight, and obesity19. Hypnosis has shown some promise in promoting these healthy behaviors. Evidence is reviewed below.
In the context of weight management, hypnosis is typically used as part of a treatment package. More specifically, hypnosis is typically added to established cognitive behavioral therapy (CBT) programs. Meta-analytic results indicate that hypnosis plus CBT can more than double the effects of CBT alone on weight loss 20. Mean weight loss associated with CBT was 6.03 pounds (2.74 kg) without hypnosis and 14.88 pounds (6.75 kg) with hypnosis. These data represent a 147% increase in treatment efficacy. Allison has commented that hypnosis is no panacea for obese patients 21. However, even in the most critical arguments, hypnosis clearly adds to the treatment efficacy of CBT weight loss programs 21. Overall, as hypnosis increases effect sizes of CBT, the extant data support its inclusion in CBT weight loss programs.
The most recent meta-analysis of randomized controlled trials of hypnosis for smoking cessation 22 identified only 4 hypnosis trials which met their rigorous inclusion criteria. The results suggest that hypnosis may help patients quit smoking (OR, 4.55; 95% CI, 0.98-21.01). However, these results should be viewed with some caution as there is a wide confidence interval - in three of the four studies the sample size is small (40 participants or less), as there was variability in duration of hypnosis administered (ranging from 80 to 480 minutes), and as there was variability as in who administered the hypnosis.
These meta-analytic results stand in contrast to previous reviews that have failed to find any support for the efficacy of hypnosis for smoking cessation 23, 24. In a 2000 review, Abbot and colleagues studied nine randomized trials of hypnosis for smoking cessation 23, and reported a great deal of heterogeneity in study results regarding whether hypnosis was more effective than either no treatment or advice. Hypnosis was not shown to be effective when compared to rapid smoking or psychological treatment. The authors conclude that there was not enough good evidence to show whether hypnosis could help with smoking cessation. In a 2010 update, Barnes and colleagues 24 examined eleven randomized trials of hypnosis for smoking cessation. Their findings were the same – the results on the effectiveness of hypnosis compared to no treatment, advice, or psychological treatment were mixed. There remained no effect of hypnosis compared to rapid smoking or psychological treatment. Despite ten years between reviews, the conclusions were the same; there is not sufficient evidence to support a benefit of hypnosis for smoking cessation.
The lack of convincing empirical support for hypnosis as a smoking cessation intervention has not dissuaded patients. A proportion of patients continue to demand, use and are able to quit smoking using hypnosis. Given that many patients prefer hypnosis for smoking cessation over other methods (e.g., nicotine replacement, buproprion) 25, more research in this area is needed to determine for which patients hypnosis might be effective. For example, a recent meta-analysis suggested that male participants in hypnosis smoking cessation programs may be more likely to quit smoking as compared to female participants 26.
More, and more rigorous, randomized trials of hypnosis for smoking cessation are needed to: 1) identify moderators of treatment effects; and, 2) examine if the addition of hypnosis to an already efficacious treatment can “boost” the effect of that treatment. To date, much of the literature has focused on hypnosis alone, rather than hypnosis as one component of a treatment package.
Hypnosis has been consistently shown to improve clinical and cost outcomes associated with diagnostic procedures. As there are no meta-analyses or systematic reviews in this area, we conducted a search in PubMed. The search terms were (“Hypnosis”[Mesh] AND “Biopsy”[Mesh]) AND Randomized Controlled Trial[ptyp]. This search yielded 7 studies, of which three were randomized trials of hypnosis used with cancer screening procedures 8, 27, 28.
First, in the strongest study in this area, Lang and colleagues 27 studied 236 women undergoing large core image-guided breast biopsy. Patients randomized to receive hypnosis had lower levels of anxiety and pain during the procedure than patients who received standard care. Furthermore, hypnosis did not cost significantly more than standard care; that is, procedure room time and overall costs were not significantly different between the hypnosis and standard care control group, despite hypnosis requiring the time and services of an additional professional (46 min/$161 for standard care and 39 min/$152 for hypnosis).
Second, Montgomery and colleagues 28 studied 20 excisional breast biopsy patients who were randomly assigned to receive either a standardized, pre-biopsy, psychologist-administered hypnosis intervention or standard care. Breast biopsy patients receiving hypnosis had significantly less post-biopsy pain than standard care patients (p<.05), tended to be more satisfied with their overall medical treatment experience, and demonstrated less distress pre- and post-biopsy (p’s < .05).
Third, Schnur and colleagues examined the effectiveness of hypnosis for controlling distress prior to excisional breast biopsy 8. Ninety patients scheduled for excisional breast biopsy were randomly assigned to either a pre-biopsy hypnosis group (n = 49, mean age: 46.4) or to a pre-biopsy attention control group (n= 41, mean age: 45.0). Following the study intervention, patients in the hypnosis group had significantly less pre-biopsy emotional upset (p < 0.0001, d = 0.85; large effect), depressed mood (p < 0.02, d = 0.67; medium to large effect), and anxiety (p < 0.0001, d = 0.85; large effect). Hypnosis patients were also significantly more relaxed (p < 0.001, d = −0.76; medium to large effect) than attention control patients.
In a 2010 paper, Block 29 projected the amount of money that might be saved if hypnosis were used for all breast biopsies conducted in the United States during a one year period. Block’s results were extrapolated from published cost-effectiveness data 6. Block estimated that if 92% of new breast cancer patients in the US (178,738 based on 2009 data) used the hypnosis intervention, $138,112,331 would be saved. Savings were then adjusted for nurses’ salaries to deliver the interventions. Using $65,183 as a salary benchmark, the cost of delivering the intervention to all cases would be $2,841,928 annually, resulting in an annual cost savings of $135,270,403. It is likely that results are not accounting for all costs associated with providing the hypnosis intervention, but it is also appears that the paper took a generally conservative approach. For example, Block only included breast cancer patients (i.e., those with positive biopsies). However, it has been estimated that 80% of breast biopsies are benign 30. By excluding these benign biopsy patients, Block may have underestimated total cost savings. Inclusion of women with benign biopsy results in the cost analyses would only increase institutional savings, perhaps by as much as a factor of five. Furthermore, Block’s estimates do not include potential individual or societal level benefits (e.g., faster return to work), which would also increase the estimate of cost-savings. In the present era of cost consciousness in healthcare, cost-effective approaches like hypnosis should be considered for widespread dissemination, or even for inclusion as part of standard clinical practice in cancer biopsy settings.
Overall, these studies indicate that hypnosis can be an effective means of controlling distress in women undergoing diagnostic breast cancer procedures. Results from an institutional cost-effectiveness perspective, indicate that at a minimum hypnosis interventions are likely to pay for themselves. That is, cost savings associated with the intervention offset additional costs associated with delivery of the intervention 27. At best, hypnosis for breast biopsy could potentially save over $100 million from an institutional perspective when extrapolated to a national level on an annualized basis 29.
There is also research indicating beneficial hypnotic effects with other (non-breast) diagnostic cancer procedures such as lumbar puncture and bone marrow aspirations. Using the search terms [“Hypnosis”[Mesh] AND (bone marrow or lumbar puncture)] and limiting studies to RCTs, we identified 8 studies in English using the PubMed database. One study was excluded because the intervention was not hypnosis, and one study was excluded because the patients were not undergoing lumbar puncture or bone marrow aspiration. Through reviewing references of these papers, we identified one additional RCT 31, leading to a total of 7 studies. Three of these studies involved patients undergoing lumbar puncture 31-33, two undergoing bone marrow aspiration 34, 35, and two studies included patients undergoing either of the procedures 36, 37. Only one paper was with adults 34, the remainder focused on pediatric samples.
Consistent with reviews focused on pediatric patients 38, hypnosis was found to be more effective than control conditions across studies in alleviating discomfort associated with lumbar punctures and bone marrow aspirations in children. In one of the stronger studies 33, a prospective controlled trial was conducted to compare the efficacy of an analgesic cream (local anesthetic) alone or combined with a hypnosis intervention to relieve lumbar puncture-induced pain and anxiety in 45 pediatric cancer patients (age 6–16 years). Patients were randomized to 1 of 3 groups: local anesthetic, local anesthetic plus hypnosis, or local anesthetic plus attention. Results revealed that patients in the local anesthetic plus hypnosis group reported significantly less anticipatory anxiety and less procedure-related pain and anxiety than patients in the local anesthetic alone group or in the local anesthetic plus attention group. Observational ratings of behavioral distress also supported the benefits of hypnosis over the two non-hypnosis comparison conditions. This study highlights the benefits of using hypnosis as an adjunct to traditional pharmacologic approaches.
From a public health perspective, colon cancer may be one of the most preventable of cancers. Colonoscopy is one of the few cancer screening procedures which both detects and removes cancerous and potentially cancerous cells 39. One of the barriers to adherence to regular colonoscopy is the discomfort of the procedure itself 40. Hypnosis may be an effective tool for reducing the discomfort of the procedure, and thereby indirectly improving adherence. Although no randomized studies have been completed with colonoscopy patients, case reports suggest potential benefits of using hypnosis. In one study that preliminarily explored the use of hypnosis with colonoscopy, 6 colonoscopy patients (5 men, 1 woman) received a hypnotic intervention on the day of their colonoscopy. Anxiety and pain during colonoscopy, perceived effectiveness of hypnosis, and patient satisfaction with medical care were assessed following colonoscopy. The results supported hypnosis as a feasible method to manage anxiety and pain associated with colonoscopy, and a potential means to reduce the need for sedation and shorten colonoscopy procedure time 41.
The vast majority of cancer patients will undergo surgery, chemotherapy, and/or radiotherapy (if not all three). Although these treatment approaches are medically necessary, they are accompanied by a wide spectrum of aversive side effects including pain, nausea, fatigue, anxiety, and depression – all of which negatively impact quality of life. Fortunately, hypnosis has shown promise in improving the patient experience of each of these treatments.
Surgical and invasive procedures
Across surgical settings, hypnosis has been demonstrated to effectively control pain and emotional distress, and to improve recovery 11. Meta-analytic results revealed a significant, large effect size (D = 1.20) for hypnosis, indicating that surgical patients in hypnosis treatment groups had better outcomes than 89% of patients in control groups. Beneficial effects were found for numerous clinical outcome categories - negative affect, pain, pain medication, physiological indicators (e.g., blood pressure), recovery (e.g., nausea, fatigue) and treatment time. As patients were drawn from a wide variety of surgical contexts (e.g., orthopedic, cardiac, gynecologic, ophthalmologic, head and neck, cosmetic), the results support the position that hypnosis is an effective intervention for a wide variety of surgical patients. These results are consistent with meta-analyses supporting significant effects of hypnosis for controlling pain (D=0.74; a medium to large effect size) 42 and emotional distress (D=0.88; a large effect size) 15 across a wide variety of patients and settings.
With regard to surgical oncology patients specifically, a randomized controlled trial of 200 patients undergoing breast cancer excisional biopsy or lumpectomy was conducted 6. Patients were assigned to either a 15-minute presurgery hypnosis session conducted by a psychologist or to a nondirective empathic listening (attention control) session. Intraoperative anesthesia use (i.e., of the analgesics lidocaine and fentanyl and the sedatives propofol and midazolam) was assessed. Patient-reported side effects were assessed at discharge, as was use of analgesics in the recovery room. Institutional costs and time in the operating room were assessed via chart review. Patients in the hypnosis group required less propofol (d=0.29, 95% CI 0.01 to 0.57; small to medium effect) and lidocaine (d=0.46, 95% CI 0.18 to 0.74; small to medium effect) than patients in the control group. Patients in the hypnosis group also reported less pain intensity (d=0.82, 95% CI 0.53 to 1.11; large effect), pain unpleasantness (d=0.57, 95% CI 0.28 to 0.85; medium to large effect), nausea (d=0.78, 95% CI 0.49 to 1.07; medium to large effect), fatigue (d=0.84, 95% CI 0.55 to 1.13; large effect), discomfort (d=0.63, 95% CI 0.35 to 0.91; medium to large effect), and emotional upset (d=0.91, 95% CI 0.62 to 1.20; large effect). Patients in the hypnosis group cost the institution $772.71 less per patient than those in the control group (95% CI = $75.10 to $1469.89), mainly due to reduced surgical time (a mean difference of 10.6 minutes).
Positive effects of hypnosis have also been seen during percutaneous tumor treatments 43. In a sample of 201 patients receiving tumor embolization or radiofrequency ablation, patients were randomized to standard care, attention, or hypnosis groups. Pain and anxiety ratings were taken every 15 minutes until 150 minutes on a zero-to-ten verbal rating scale. Patients in the hypnosis group had significantly less pain and anxiety than patients in standard care or empathic attention groups over the course of the procedure. Hypnosis group pain and anxiety scores were less than the other two groups at every assessment point over time. Hypnosis group patients also received significantly less medication (midazolam or fentanyl) than patients in the standard care (33% less medication) or empathic attention (43% less medication) groups. These results support the use of hypnosis during this invasive procedure.
In pediatric cancer patients, hypnosis has been shown to reduce pain and anxiety associated with venipuncture 44. In a prospective randomized trial, 45 pediatric cancer outpatients (age 6-16 years) were randomized to one of three groups: local anesthetic, local anesthetic plus hypnosis, and local anesthetic plus attention. Results demonstrated that patients in the local anesthetic plus hypnosis group reported significantly less anticipatory anxiety, less procedure-related pain, and less procedure-related anxiety than patients in the other two groups. Additionally, patients in the local anesthetic plus hypnosis group demonstrated significantly less behavioral distress during venipuncture.
Overall, the evidence supporting the use of hypnosis for managing side effects of surgery and invasive procedures is strong and consistent. Clinical efficacy has been widely demonstrated. Cost-effectiveness has been demonstrated in one methodologically sound RCT. These data argue for the more widespread adoption of hypnosis with cancer patients and survivors undergoing invasive treatment.
One of the first modern applications of hypnosis with cancer patients was hypnosis for the control of nausea and vomiting associated with chemotherapy 45. Redd and colleagues administered hypnosis to six adult female cancer patients, and results revealed that hypnosis suppressed anticipatory emesis in all cases. This work touched off a number of studies demonstrating the efficacy of hypnosis for controlling cancer chemotherapy-related nausea and vomiting.
Richardson and colleagues 46 systematically reviewed randomized controlled trials (RCTs) of hypnosis for controlling nausea and vomiting associated with cancer chemotherapy. Six RCTs were found and analyzed. In five of six studies, the participants were pediatric cancer patients. Studies reported positive results including statistically significant reductions in nausea and vomiting. Meta-analysis revealed a large effect size of hypnotic treatment when compared with treatment as usual, moderate when compared to attention control, and the effect was at least as large as that of cognitive–behavioral therapy. This review supported the use of hypnosis in the pediatric setting. However, due to the small number of RCTs reviewed in the paper, theses conclusions should be viewed with caution. The generalizability of the findings to adult cancer patients also remains unclear; thus, more research is needed in this area with a particular need for an RCT with adult cancer patients. Additionally, this review noted several methodological concerns with the hypnosis-nausea/vomiting literature, including that: study sample sizes have generally been small, power analyses were generally not performed, the method of randomization was not clear, and intent to treat analyses were typically not performed 46. Some of these concerns may be due to the fact that most of the research was conducted in the 1980s, before CONSORT and other reporting standards were widely adopted. The fact that this is an older literature raises another potential concern: much of this research was conducted before the widespread availability of modern anti-emetics, potentially limiting the generalizability of the results. However, research has indicated that nausea and emesis continue to be problems for cancer patients despite improvements in pharmacotherapy 47, and it is therefore probable that a role for hypnosis interventions to control nausea remains.
A second review of the literature on hypnosis and cancer chemotherapy-related nausea and vomiting literature 48 also supports the efficacy of hypnosis. In this review, which included both randomized and non-randomized research, results similarly suggested that hypnosis was efficacious for controlling nausea and vomiting. This study pointed out, however, that much of the literature has focused on anticipatory nausea and vomiting, and that the effects of hypnosis on post-chemotherapy nausea and vomiting are unclear. Effect sizes have generally been shown to be greater for anticipatory nausea and vomiting. Further investigation is necessary to better understand and improve hypnotic effects on post-chemotherapy symptoms.
Unlike the surgical hypnosis literature, there have been no large-scale RCTs and no cost-effectiveness trials of hypnosis for nausea. Cost-effectiveness analyses are particularly critical given the expense associated with chemotherapy-induced nausea and vomiting. A recent publication 49 reported that among 11,495 study patients, chemotherapy-induced nausea and vomiting was associated with a treatment cost of $89 million, and an average daily treatment cost of $1,854.70. If hypnosis can reduce nausea and vomiting, it not only has the potential to be of clinical benefit, but also to save scarce healthcare dollars.
To our knowledge, only three randomized trials have been conducted to explore the effects of hypnosis in the radiotherapy setting. The first, by Montgomery and colleagues 7 examined the effects of a psychotherapeutic intervention combining cognitive-behavioral therapy and hypnosis (CBTH) on fatigue in breast cancer radiotherapy patients. The decision to combine cognitive-behavioral therapy with hypnosis was based on a meta-analysis demonstrating that CBT plus hypnosis is more effective than CBT alone 50In this study, 42 breast cancer radiotherapy patients were randomly assigned to receive either standard medical care or CBTH. Multilevel modeling revealed an effect of CBTH over time, such that fatigue increased over the course of treatment among control participants, whereas fatigue did not increase significantly over the course of treatment among CBTH participants. By the conclusion of radiotherapy, patients in the CBTH group had, on average, 32% less fatigue on average than patients in the control group based on the Functional Assessment of Chronic Illness Therapy-fatigue subscale (FACIT-F) scores. Effects were similar using daily visual analog scale (VAS) measures of fatigue (a 22% difference) and muscle weakness (a 52% difference). Effect sizes for effects over time ranged from medium (daily fatigue VAS, d= .65; daily muscle weakness VAS, d = .59) to large (FACIT-F, d = .82) according to Cohen’s criteria 14. These results suggest that CBTH can not only manage fatigue, but possibly even prevent the development of fatigue in breast cancer radiotherapy patients.
Schnur and colleagues 9 conducted a randomized trial of 40 breast cancer radiotherapy patients to evaluate the effects of CBTH on positive and negative affect. Participants were randomized to receive either CBTH or standard care. Results revealed that CBTH significantly reduced levels of negative affect and increased levels of positive affect over the course of radiotherapy. At week five, patients in the CBTH group had 66% lower negative affect scores on average than the control group, and 43% greater positive affect scores than the control group. Additionally, CBTH participants had more intense positive affect and less intense negative affect during radiotherapy. Finally, participants in the CBTH group reported a higher number of radiotherapy treatment days when positive affect was greater than negative affect. In sum, the CBTH intervention helped women to feel better emotionally during breast cancer radiotherapy.
A study by Stalpers and colleagues showed more mixed results 51. These authors randomly assigned 69 patients to receive either standard care or hypnosis. Results revealed no statistically significant between-group differences in anxiety or quality of life. However, 52% of the participants in the hypnosis group reported that study participation had improved their mental well-being (as opposed to none of the control participants, p<0.05) and 55% of the participants in the hypnosis group reported an improvement in overall well-being (as opposed to 11% of the controls, p<0.05). Furthermore, nearly two-thirds of the participants in the hypnosis group reported that they had benefited from hypnosis, and all of the hypnosis patients reported that they would recommend hypnosis to other patients.
Thus, the findings in this area are somewhat mixed. Between-study differences may be explained by four possible factors: a) Our group has focused exclusively on female breast cancer patients, whereas the study by Stalpers and colleagues included prostate, breast, skin, uterine/cervix, lung, lymphoma, larynx, bladder, and brain patients. It is possible that gender or diagnostic differences may explain differences in the results; b) The suggestions included in our group’s hypnosis were specifically focused on breast cancer radiotherapy and associated side effects (i.e., fatigue, distress), whereas the suggestions in the Stalpers study seem to have been less disease/symptom specific, and more focused on general well-being; and c) Perhaps most importantly, in the work by our group, participants received hypnosis in combination with cognitive-behavioral therapy. In the study by Stalpers’ group, hypnosis was used on its own. These results suggest that for radiotherapy patients, hypnosis may be best delivered as one component of a larger intervention.
Four limitations of the present studies should be noted. First, they all have relatively small sample sizes. Second, none of these studies compared hypnosis to an attention control condition. Although results of these early studies are promising, one cannot yet definitively state that hypnosis is of greater benefit than non-specific professional attention in radiotherapy settings. Therefore, we recommend that future RCTs in radiotherapy focus on further elucidating the mechanisms of hypnosis effects and identifying whether hypnosis demonstrates benefit over and above attention alone. Third, the studies reviewed in this area all focused on acute radiotherapy side-effects. Future research should examine whether hypnosis can have longer-term benefits as well. Fourth, similar to the chemotherapy setting, no cost-effectiveness analyses have yet been performed in the radiotherapy setting. Larger scale RCTs, incorporating cost-effectiveness analyses and longer-term follow-ups, would contribute to the understanding of hypnotic effects in this context.
According to the National Cancer Institute, “survivorship focuses on the health and life of a person with cancer post treatment until the end of life. It covers the physical, psychosocial, and economic issues of cancer, beyond the diagnosis and treatment phases”52. According to the American Cancer Society, as of January 1, 2012 there were approximately 13.7 million cancer survivors in the United States53. This number may actually be an underestimate since this count does not include most in situ cases, or basal cell and squamous cell skin cancers. Many survivors, even those who have finished their cancer treatment, continue to experience impaired quality of life including side effects such as chronic pain and neuropathy, cognitive problems, fatigue, fear of cancer recurrence, hot flashes, and sexual dysfunction53.
Using the following search terms in PubMed, (((“survivors”[MeSH Terms] OR survivor[Text Word]) AND “Survivors”[Mesh]) AND “Neoplasms”[Mesh]) AND “Hypnosis”[Mesh], and limiting to RCTs, one randomized study of hypnosis with cancer survivors was identified. The study focused on hot flashes in breast cancer survivors. Elkins and colleagues 54 randomized 60 breast cancer survivors with hot flashes to receive either hypnosis (delivered in five weekly sessions, and including self-hypnosis instructions, recommended self-hypnosis practice, and an audiocassette recording of hypnosis) or no treatment. At the conclusion of the study, participants in the hypnosis group reported significantly greater improvements in hot flashes, hot flash interference with daily activities, sleep, anxiety, and depression than participants in the control group. Results indicate that hypnosis successfully addressed not only hot flashes, but other common survivorship complaints as well (e.g., sleep). A great deal more work needs to be done to investigate the potential benefits of hypnosis among cancer survivors, as well as cost-effectiveness.
There has been widely publicized research on the use of hypnosis with metastatic breast cancer patients. In 1983, Spiegel and Bloom 55 found that weekly group therapy combined with hypnosis was associated with less pain sensation and suffering, and with improved mood, in metastatic breast cancer patients. These results were later replicated in a larger sample 56. In 1989, Spiegel and colleagues 57 found that survival time was significantly longer in a group of metastatic breast cancer patients randomly assigned to receive supportive group therapy including hypnosis (mean of 36.6 months) as compared to a routine care control group (mean of 18.9 months). In a 2007 replication study, Spiegel and colleagues 58 randomized metastatic or locally recurrent breast cancer patients to receive either group therapy including hypnosis or to a control condition. In this study, the authors found that on average, the intervention group did not live significantly longer than the control group. However, exploratory analyses suggested a survival benefit among the 25 estrogen receptor (ER)-negative patients. More specifically, ER-negative intervention patients survived significantly longer than ER-negative control patients. No such effect was demonstrated in ER-positive participants.
Much of this line of research is consistent with the hypnosis studies reviewed above. Like past research, these studies reveal that hypnosis (here in combination with group therapy) effectively ameliorates pain and emotional distress associated with breast cancer. However, the findings of a survival benefit are unique, and have sparked a great deal of controversy and debate in the cancer community. A discussion of that debate is beyond the scope of the present paper. However, we would like to point out that even if the intervention had shown no benefit with regard to improving metastatic patients’ quantity of life, it still improved their quality of life. As has been demonstrated so many times before, hypnosis has contributed to patients being more comfortable and less distressed as they live with their disease.
Overall, a great deal more work is needed to investigate the benefits of hypnosis with metastatic, end of life, and palliative care patients, especially among patients with cancers other than breast.
Section 3: Discussion and Future Directions
The literature reviewed above describes where hypnosis has been. Below, we describe where hypnosis can go and how hypnosis can grow. We will focus on 6 future research directions, which include the need: 1) for larger scale randomized trials incorporating appropriate controls, cost-effectiveness analyses, and comparative effectiveness analyses; 2) to test new methods of hypnosis delivery; 3) to extend hypnosis research to cancers other than breast; 4) for an increased focus on survivorship; 5) for mechanism studies; and, 6) for dissemination/translation research.
Larger scale randomized trials incorporating appropriate controls, cost-effectiveness analyses, and comparative effectiveness analyses
In writing this review, we noted how hypnosis can be effective in helping to improve cancer patients’ quality of life and experience of treatment. Yet, it was also apparent how few large scale randomized controlled trials had been conducted on hypnosis for cancer patients. So many areas have had many promising small scale studies, but lack “the” definitive RCT. When thinking about the research literature on hypnosis and cancer, we cannot help but describe it as 200 years young. The technique has been used since the 1800s, yet it is only now beginning to mature. More research is needed to build on this foundation and conclusively demonstrate what many clinicians already sense; that hypnosis helps cancer patients cope with their diagnosis and treatment.
Much of the hypnosis literature involves case studies, small sample non-randomized studies, and comparison only with standard care controls. Such work is of great value in that it can introduce readers to innovative ideas and treatment strategies, and can be a critical first step in intervention development. However, such work is insufficient to provide strong, persuasive empirical support for the more widespread use of hypnosis interventions, or even for gaining hypnosis recognition as an empirically supported treatment. With shrinking healthcare dollars, and increased emphasis on empirically supported treatments, hypnosis researchers cannot rest on the extant small scale studies. Larger, appropriately powered trials of hypnosis, including cost-effectiveness analyses, in cancer settings are needed.
Method of delivery studies
Beyond the traditional live and recorded delivery formats, research has begun to explore the use of new technologies to deliver hypnosis. For example, a series of papers have been published demonstrating the promise of delivering hypnosis via immersive virtual reality (e.g., 59-65). Future research comparing the clinical efficacy and cost-effectiveness of virtual reality hypnosis to live and recorded methods would further strengthen the argument for this method of delivery.
Another new delivery option is hypnosis delivered over the Internet (E-hypnosis) – either with therapist participation (e.g., via videoconferencing) or without (e.g., downloadable hypnosis recordings). To our knowledge, only one randomized trial of Internet-based hypnosis has been conducted 66. E-hypnosis is likely to be easily accepted by cancer patients in light of the fact that nearly 40% of the U.S. population has searched for cancer information at some point and the most frequently used source of cancer information was the Internet (55.3%)67, that cancer is one of the top two diseases about which people seek information on the Internet 68, and that meta-analyses have indicated that patients of all ages can benefit from online therapy 69. We anticipate that E-hypnosis also has the potential to be a great boon to cancer patients, especially those who are too tired or too ill to travel to meet with a hypnotist in person.
Finally, a quick look at the iTunes store reveals over 1,000 hypnosis apps available for download. Although to our knowledge none has been empirically tested and few have been developed by healthcare professionals, smartphone applications may be the wave of the future in terms of hypnosis delivery.
Extension to cancers other than breast
The vast majority of the research on hypnosis and cancer thus far has focused on breast cancer. This trend likely represents the fact that breast cancer is one of the most common cancers. However, prostate cancer, lung cancer, and colorectal cancer are also all too common, and their treatments can be associated with suffering and side effects, including: incontinence, impotence, hot flashes, shortness of breath, fatigue, constipation, diarrhea, or the need for a colostomy. We hope that future hypnosis research will attend to the needs of these patients as well.
Increased focus on survivorship
As noted above, we identified a single RCT focused on cancer survivors. Individuals with cancer do not stop needing help the day acute treatment ends. Hypnosis has the potential to not only help with physical side effects during survivorship, but to help with the emotional issues associated with living with uncertainty and adjusting to reduced contact with medical providers. Research efforts should be made in the area of hypnosis to improve cancer survivorship.
To our knowledge, there is only one randomized trial which has directly explored mediators of hypnotic effects in the cancer setting. Montgomery and colleagues 5 investigated whether the beneficial effects of hypnosis on postsurgical recovery in breast cancer surgical patients might be mediated by either emotional distress or expectations for postsurgical symptoms. In 200 breast conserving surgery patients, structural equation modeling revealed that: 1) expectations partially mediated the effects of hypnosis on postsurgical pain (p<.0001) and fatigue (p<.0001); and, 2) emotional distress partially mediated the effects of hypnosis on postsurgical nausea (p<.02) and fatigue (p<.02). In other words, at least in part, hypnosis works by reducing patients’ presurgical levels of expectations for postsurgical side effects, and by helping them feel less distressed prior to surgery. These findings are consistent with a recent review by Stanton and colleagues 70 which suggests that two of the promising mechanisms for the effects of psychosocial interventions in adult cancer patients are cognitive factors (including expectations) and psychological symptoms (including emotional distress). However, a considerable amount of additional research is needed to fully elucidate the mechanisms by which hypnosis helps cancer patients and survivors.
Despite empirical evidence supporting the use of hypnosis in cancer settings, hypnosis has failed to be widely adopted. Hypnosis does not appear to be currently popular, and in fact has failed to increase in popularity in the United States over time 71, 72 despite empirical support. The field of implementation science teaches us that successful efficacy trials should not be considered the conclusion of a program of research, but rather, an initial stage 73-75. The next question to be answered is how can we ensure that this intervention will actually be provided to patients in need (i.e., will implementation occur?) 73-75? To our knowledge there has been no implementation research focused on increasing the utilization of hypnosis in the context of cancer care. We recommend implementation studies as a critical avenue of future research.
A potential explanation of the failure of hypnosis to be widely disseminated is the lack of clarity over where hypnosis fits into the larger healthcare system. In many cases, hypnosis is placed within the complementary and alternative medicine domain. However, this is not as clear a designation as one might first think. For example, hypnosis is clearly not “alternative”. The best use of hypnosis is not to replace traditional approaches to anesthesia or other medical treatments, but rather to be used as an adjunct to best clinical practices. Just as icing makes a cake taste better, hypnosis can improve clinical outcomes when added to traditional care. Then the question remains, should hypnosis be considered complementary? We would argue not. The term “complementary medicine” has a lot of connotations, many of which are often negative. Complementary interventions are often viewed as untested and unreliable. What we hope to have demonstrated here is that in some contexts, hypnosis interventions have strong empirical support, and there are several promising areas. Our hope for the future is that hypnosis be considered as an “integrative” intervention that can improve cancer patients’ quality of life. This terminology has the advantage of conveying the impression that this approach is not “instead of” conventional care, but rather integrated with traditional medical care for enhancing patient outcomes.
The goal of this review was to summarize the empirical literature on hypnosis as an integrative cancer prevention and control technique. We have reviewed where hypnosis has strong support for its efficacy (surgery and other invasive procedures), where it holds promise (weight loss, chemotherapy, radiotherapy, metastatic disease), and where more work is needed.
Overall, we hope that this review has served to dispel misconceptions about hypnosis (e.g., that it is unscientific), to answer questions about hypnosis, to help the reader feel more comfortable and more relaxed about the notion of using hypnosis with cancer patients and survivors, to be able to imagine using hypnosis in their own clinical practice, and perhaps to consider using this review as a starting point to learn more about hypnosis. We hope that this review has served to both satisfy and stimulate the reader’s intellectual curiosity. We encourage clinicians and researchers to learn more about hypnosis, and to consider seeking training in this technique. However, paraphrasing O’Hanlon and Martin, we’re only hypnotists, so this is only a suggestion 76.
Supported by the National Cancer Institute (NCI) (grant CA129094). Dr. Montgomery was supported by NCI grant CA081137. Dr. Schnur was supported by NCI grant CA131473. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NCI or the National Institutes of Health.
*By convention, for between-group differences, an effect size (d, g, D) of 0.20 is considered small, 0.50 medium, and .80 large 14.