Feasibility study of Transcutaneous Electrical Nerve Stimulation (TENS) for cancer bone pain. Randomization is important in studies with pain outcomes: systematic review of transcutaneous electrical nerve stimulation in acute postoperative pain. TENS for children's procedural pain. Use of transcutaneous electrical nerve stimulation for postoperative pain. Evaluation of TENS during screening flexible sigmoidoscopy. Implementing guidelines for cancer pain management: results of a randomized controlled clinical trial. Developing a database of published reports of randomised clinical trials in pain research. Prediction and management of pain in patients with advanced cancer. Evolution of the randomized controlled trial in oncology over three decades.
This multicenter study assessed the feasibility of conducting a phase III trial of transcutaneous electrical nerve stimulation (TENS) in patients with cancer bone pain recruited from palliative care services. Eligible patients received active and placebo TENS for 1 hour at site of pain in a randomized crossover design; median interval between applications 3 days. Responses assessed at 30 and 60 minutes included numerical and verbal ratings of pain at rest and on movement, and pain relief. Recruitment, tolerability, adverse events, and effectiveness of blinding were also evaluated. Twenty-four patients were randomised and 19 completed both applications. The intervention was well tolerated. Five patients withdrew: 3 due to deteriorating performance status, and 2 due to increased pain (1 each following active and placebo TENS). Confidence interval estimation around the differences in outcomes between active and placebo TENS suggests that TENS has the potential to decrease pain on movement more than pain on rest. Nine patients did not consider that a placebo was used; the remaining 10 correctly identified placebo TENS. Feasibility studies are important in palliative care prior to undertaking clinical trials. Our findings suggest that further work is required on recruitment strategies and refining the control arm before evaluating TENS in cancer bone pain.
                Cancer bone pain is common and severe, and partly mediated by hyperexcitability. Animal studies suggest that Transcutaneous Electrical Nerve Stimulation can reduce hyperalgesia. This study examined the feasibility of evaluating TENS in patients with cancer bone pain in order to optimize methods before a phase III trial.
                Copyright 2010 American Pain Society. Published by Elsevier Inc. All rights reserved. We set out to examine the evidence for the importance of randomization of transcutaneous electrical nerve stimulation (TENS) in acute postoperative pain. Controlled studies were sought; randomization and analgesic and adverse effect outcomes were summarized. Forty-six reports were identified by searching strategies. Seventeen reports with 786 patients could be regarded unequivocally as randomized controlled trials (RCT) in acute postoperative pain. No meta-analysis was possible. In 15 of 17 RCT, we judged there to be no benefit of TENS compared with placebo. Of the 29 excluded trials, 19 had pain outcomes but were not RCT; in 17 of these 19 TENS studies, the authors concluded that TENS had a positive analgesic effect. No adverse effects were reported. Non-randomized studies overestimated treatment effects. A 3 x 6 factorial design with a double blind and placebo control was employed to investigate the effect of TENS treatment on pain produced by venipuncture. The three treatment groups consisted of TENS, placebo-TENS and control. Subjects were blocked into six 2-year age groups (ages: 5-17 years). During the period of the study, 896 children attending the outpatient laboratory of a general hospital were screened and 514 children completed the study. The data which were collected before venipuncture included expected pain and state anxiety. Following venipuncture, pain intensity was measured with a vertical visual analogue scale (VAS) and pain affect was assessed with McGrath's faces scale. Significant main effects for treatment and age groups were obtained. Pain intensity and affect were lowest for the TENS group and highest for the control group. The pain scores were greatest for lower age groups and lowest for higher age groups. The results of this study support the use of TENS for children's pain and the need for interventions for children's procedural pain. This study examined the effects of transcutaneous electrical nerve stimulation (TENS) on incisional pain caused by the procedure of cleaning and packing an abdominal surgical wound. Seventy-five subjects (mean age 56.9 years) were randomly assigned to one of three intervention groups: TENS, placebo-TENS, or no-treatment control. The appropriate experimental treatment was administered during the routine dressing change which took place two mornings after surgery. Using an 11-point, visual analogue pain scale, subjects described pain experienced during the dressing change. Subjects who received TENS reported a significantly lower level of pain after dressing change than did those subjects who received either placebo-TENS or no-treatment. Drug administration variables did not contribute significantly to level of reported pain. The expectation of pain is a statistically significant factor negatively affecting patient compliance with current screening flexible sigmoidoscopy recommendations. Numerous pain reduction modalities have been studied with limited success. Transcutaneous electrical nerve stimulation (TENS) has been used to treat pain of various origins. The purpose of this pilot study was to determine the efficacy of TENS in reducing discomfort experienced during screening flexible sigmoidoscopy.A double-blind study was conducted in which 90 subjects were randomized to receive TENS, sham TENS, or control (standard care). The same pulse frequency and intensity were used for all subjects in the TENS group. Subjects completed preprocedural and postprocedural questionnaires, and the endoscopist completed a postprocedural questionnaire. A slight, but statistically insignificant (p =.526) reduction in the mean pain score reported by the TENS group was noted when compared with the sham TENS and control groups (2.00, 2.27, and 2.23 respectively). In light of the fact that only one pulse frequency and intensity of the TENS intervention were used in this study, further study with this safe and cost-effective modality is warranted. Pain and symptom management is an integral part of the clinical practice of oncology. A number of guidelines have been developed to assist the clinician in optimizing comfort care. We implemented clinical guidelines for cancer pain management in the community setting and evaluated whether these guidelines improved care.
                Eighty-one cancer patients, aged 37 to 76 years, were enrolled onto a prospective, longitudinal, randomized controlled study from the outpatient clinic settings of 26 western Washington-area medical oncologists. A multilevel treatment algorithm based on the Agency for Health Care Policy and Research Guidelines for Cancer Pain Management was compared with standard-practice (control) pain and symptom management therapies used by community oncologists. The primary outcome of interest was pain (Brief Pain Inventory); secondary outcomes of interest were all other symptoms (Memorial Symptom Assessment Scale) and quality of life (Functional Assessment of Cancer Therapy Scale).
                Patients randomized to the pain algorithm group achieved a statistically significant reduction in usual pain intensity, measured as slope scores, when compared with standard community practice (P < .02). Concurrent chemotherapy and patient adherence to treatment were significant mediators of worst pain. There were no significant differences in other symptoms or quality of life between the two treatment groups.
                This guideline implementation study supports the use of algorithmic decision making in the management of cancer pain. These findings suggest that comprehensive pain assessment and evidence-based analgesic decision-making processes do enhance usual pain outcomes. A database of randomised clinical trials (RCTs) in pain research published from 1950 to 1990 was created following an extensive literature search. By applying a refined MEDLINE search strategy from 1966 to 1990 and by hand-searching more than 1,000,000 pages of a total of 40 biomedical journals published during the period 1950-1990, more than 8000 RCTs were identified. The RCTs were published in more than 800 journals and over 85% appeared between 1976 and 1990. If the trend of the last 15 years persists, a total of more than 15 000 RCTs will be published in pain relief by the year 2000. A detailed description of methods to ensure efficient use of resources during the identification, retrieval and management of the information in pain relief and other fields is given. Emphasis is made on the importance of refining MEDLINE search strategies, on the use of volunteers to hand-search journals and on careful monitoring of each of the steps of the process. The potential uses of the database to guide clinical and research decisions are discussed. In a prospective controlled study, patients with incurable cancer and an estimated prognosis of three months to one year were allocated to two patient groups for evaluation of supportive interventions. One group, called "intensive," received home visits by a nurse practitioner acting as an extension of a multidisciplinary team; the other, termed "nonintensive," did not receive such visits. Both patient groups were periodically evaluated in their homes by an observer and by self-ratings, to measure changes in quality of life as their disease progressed. Several methodologic problems were identified, which have implications for future research. Pain problems later in the course of cancer seem to be predictable in those patients with higher scores on the Cornell Medical Index M-R scales (greater emotional disturbance) and on the Rotter Locus of Control (I-E) scale (expectation of more external control of self). The study also found that the home visiting nurse practitioners, specially trained in pain treatment, improved pain control in the "intensive" group of patients over the last 90 days of life, when pain was an increasingly major problem. Such nurses can significantly improve the quality of life for patients dying outside of institutions. The randomized controlled trial (RCT) is the gold standard for establishing new therapies in clinical oncology. Here we document changes with time in design, sponsorship, and outcomes of oncology RCTs.
                Reports of RCTs evaluating systemic therapy for breast, colorectal (CRC), and non-small-cell lung cancer (NSCLC) published 1975 to 2004 in six major journals were reviewed. Two authors abstracted data regarding trial design, results, and conclusions. Conclusions of authors were graded using a 7-point Likert scale. For each study the effect size for the primary end point was converted to a summary measure.
                A total of 321 eligible RCTs were included (48% breast, 24% CRC, 28% NSCLC). Over time, the number and size of RCTs increased considerably. For-profit/mixed sponsorship increased substantially during the study period (4% to 57%; P < .001). There was increasing use of time-to-event measures (39% to 78%) and decreasing use of response rate (54% to 14%) as primary end point (P < .001). Effect size remained stable over the study period. Authors have become more likely to strongly endorse the experimental arm (P = .017). A significant P value for the primary end point and industry sponsorship were each independently associated with endorsement of the experimental agent (odds ratio [OR] = 19.6, 95% CI, 8.9 to 43.1, and OR = 3.5, 95% CI, 1.6 to 7.5, respectively).
                RCTs in oncology have become larger and are more likely to be sponsored by industry. Authors of modern RCTs are more likely to strongly endorse novel therapies. For-profit sponsorship and statistically significant results are independently associated with endorsement of the experimental arm.
Despite the one additional RCT, the results of this updated systematic review remain inconclusive due to a lack of suitable RCTs. Large multi-centre RCTs are required to assess the value of TENS in the management of cancer-related pain in adults.