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Pain is a common symptom associated with cancer and its treatment. Pain management is an important aspect of oncologic care, and unrelieved pain significantly comprises overall quality of life. These NCCN Guidelines list the principles of management and acknowledge the range of complex decisions faced in the management oncologic pain. In addition to pain assessment techniques, these guidelines provide principles of use, dosing, management of adverse effects, and safe handling procedures of pharmacologic therapies and discuss a multidisciplinary approach for the management of cancer pain.

In 1914, Crile introduced the concept of individualized or personalized pain therapy as well as demonstrating that good postoperative pain control greatly decreased postoperative mortality. Schweitzer equated severe pain associated with a disease to torture, and in 1953 Bonica clearly elucidated the serious deleterious effects caused by severe acute pain. Nonetheless, the medical profession devotes very little attention to this disease. The majority of medical school’s curricula and graduate medical education have refused to teach the advances made by clinical and basic research in pain medicine, or algology, and misconceptions continue to be perpetuated in spite of new scientific knowledge. A 2009 study, reported that only 32.5% of the Canadian medical students receive an average of 16 h of formal education in algology while the other 67.5% have no formal pain education. During the last 45 years, clinical and basic research has made many discoveries. Most important among them is that pain is a disease in its own right, that it is largely under treated and that genetic differences among people greatly influence the response of individuals to the perception of pain and analgesic therapy. Crile’s clinical observation regarding the need for individualized pain therapy is now strongly supported by the scientific discoveries of genetic heterogeneity and is at the core of present pain therapy. However, pain medicine education is so limited that the research discoveries made in algology are unknown to most physicians and other health care professionals and, in most of the cases, pain is still poorly treated.

Patients who are suffering from chronic gastrointestinal illnesses, particularly cancer, are human beings in the throes of physical, psychosocial, and spiritual crises that comprise their total pain [1–3]. The patient and primary care physician may seek the gastroenterologist to manage symptoms of advanced illnesses [4,5]. When cure is not feasible, palliative care tools are available to ease a patient’s suffering. When pain is a prominent symptom, the gastroenterologist may include percutaneous-guided techniques in the therapeutic toolbox. Help in this area may be as close as the nearest pain medicine specialist, anesthesiologist, or interventional radiologist. To date, no percutaneous procedure has replaced systemic analgesic therapy (SAT) with opioids. However, percutaneous-guided pain control interventions have earned a role in the multidisciplinary approach to pain therapy. Given that afferent sensory fibers of abdominal and pelvic organs travel in sympathetic ganglia, a chemical or surgical sympathectomy for visceral pain is analogous to a peripheral nerve block or dorsal rhizotomy for somatic pain. Most percutaneous-guided procedures in the abdomen are performed with imaging localization and local anesthetic or contrast medium injections to confirm effective spread [6]. Percutaneous techniques may be complex and highly operator-dependent, but time-tested procedures have demonstrated efficacy and safety in the hands of experienced clinicians. Although percutaneous neurolysis is usually performed to treat cancer pain, some investigators have approached noncancer pain with similar techniques.

Pain physicians in Ohio come from many medical backgrounds and use different medical boards to claim board certification in the field of pain medicine. Our goal was to explore the number, demographics, and qualifications of pain physicians in Ohio. The names of Ohio physicians designating themselves as pain physicians were collected from the State Medical Board of Ohio and the American Medical Association. The directories of the American Board of Medical Specialties (ABMS), the American Board of Pain Medicine, the American Academy of Pain Management, and the American Board of Medical Acupuncture were referenced for certification in pain medicine, pain management, or medical acupuncture. The requirements for these credentials vary widely, yet they have all been used to claim "board certification." Board certification in medicine implies recognition by an ABMS member board as having completed the required training, met the standards, and then passed an examination that validates qualifications, and knowledge in a specific medical field. In 2002, there were 335 Ohio physicians designating themselves as pain physicians. Two-hundred-eighteen (65%) had at least one pain board certification. Ninety-six (29%) of the Ohio pain physicians were certified in pain medicine by the American Board of Anesthesiology, the American Board of Physical Medicine and Rehabilitation, or the American Board of Psychiatry and Neurology, which are all member boards of the ABMS. One-hundred-seventeen (35%) of the self-declared Ohio pain physicians held no pain-related board certification. Anesthesiologists comprise the majority of all pain physicians and are the majority in all four pain boards.

In “The Tragedy of Needless Pain”, an article Ronald Melzack published in the Scientific American in 1990, the author points out that over 80% of patients with cancer pain can obtain good pain relief if the available knowledge of pain therapy is properly applied. He further states that, since the majority of cancer pain patients continue to suffer agonizing pain, their pain is needless. Ten years later the tragedy of the under treatment of pain continues to be a major health problem worldwide and a disgrace for the health care profession and society. Every year in the United States of America there is one person every 1,000 people who dies after weeks or months of severe under treated cancer pain. Of the 38.8 million Americans who suffer moderate to excruciating acute pain, 51% do not receive proper pain control, while of the 50 million with chronic intractable non cancer pain proper pain relieve is achieved in less than 30% of the patients. While most advances in medicine are dependent on new discoveries prompted by basic and clinical research, pain therapy is hindered by two major barriers: lack of education on the subject and limited research funding. Pathophysiology and therapy of pain is at best marginally taught in medical, nursing and pharmacy schools. Therefore, the great majority of health care professionals have very little or no knowledge, and often have misconceptions, on the subject. For this reason, while 80 to 90% of patients suffering intense pain associated with advanced cancer could obtain proper pain control, albeit with some side effects caused by the analgesic medications, only 30% of them report acceptable pain relief. The majority of physicians also fail to appreciate that poorly treated intense pain not only causes misery for the patient but, it can have serious deleterious effects caused by inactivity, lack of sleep, anorexia, anxiety, depression of the immune system, and reactive depression. Therefore pain should be treated not only for humanitarian, but also for medical reasons. This generalized lack of education on pain is also responsible for the limited research funding granted to this field since the people entrusted with funding pain research projects suffer from the same ignorance. For instance, in 1999 the National Cancer Institute funded research projects for a total of $3.065 billion; 0.8% of this funding, or $24 million, was designated for research in pain and symptom control. It must be underlined that of all patients who are now affected by cancer 48% will die because of it and that 75% of them will develop severe pain and other distressing symptoms. The very limited funding for research on pain is responsible for the significant deficiency that still exists in the knowledge regarding the pathophysiology and therapy of pain. The most effective medication to control intense pain is morphine, or some of its derivatives. Morphine was isolated from opium almost 200 years ago, and opium has been used for pain control for over 3,500 years. Despite the great advances made in medicine during the last hundred years, the control of intense pain still relies on one of the oldest plant extracts known to mankind with all the side effects associated with its use. If we wish to eradicate unnecessary pain, which is a scourge of humanity, more education, new discoveries, and more advocacy for the suffering pain patients are needed.

The use of opioids for postoperative analgesia may be limited by side effects such as nausea and vomiting. Because ondansetron, a selective serotonin type 3 (5-hydroxytryptamine [5-HT3]) antagonist, is effective for chemotherapy and general anesthesia-induced nausea and vomiting, we hypothesized that it may also be effective for opioid-induced nausea and vomiting. ASA physical status I-III patients undergoing regional anesthesia were eligible for the study. Those who requested an antiemetic after postsurgical opioid administration were randomized to receive a single dose of ondansetron (0.1 mg, 4 mg, or 16 mg intravenously [I.V.]) or placebo in a double-blind fashion. Emetic episodes, nausea and pain ratings, and adverse events were recorded for 24 h after study drug administration. Patient satisfaction scores were obtained 24 h after study drug infusion. A significantly (P < 0.05) larger proportion of patients treated with ondansetron 4 mg and 16 mg experienced no emetic episodes, received no rescue antiemetic, and completed the study compared with placebo. Nausea scores and patient satisfaction scores in the ondansetron 16-mg group were significantly (P < 0.05) more favorable than in the placebo group. Postsurgical pain scores did not differ among groups. The incidence of adverse events was similarly low across groups. The results of this study support our hypothesis that I.V. ondansetron is effective for postsurgical opioid-induced nausea and vomiting.

Pain is a common symptom associated with cancer and its treatment. Pain management is an important aspect of oncologic care, and unrelieved pain significantly comprises overall quality of life. These NCCN Guidelines list the principles of management and acknowledge the range of complex decisions faced in the management oncologic pain. In addition to pain assessment techniques, these guidelines provide principles of use, dosing, management of adverse effects, and safe handling procedures of pharmacologic therapies and discuss a multidisciplinary approach for the management of cancer pain.

Refractory cancer pain may be effectively controlled by titrating intracerebroventricular (ICV) preservative-free opioid. In this case report, a continuous infusion of ICV morphine permitted our patient with lung cancer and painful spinal metastases to be discharged to home hospice with family. The approach exploits the high potency of morphine injected into cerebrospinal fluid (CSF). Sterile, injectable, preservative-free morphine is directly infused into CSF through a subcutaneous Ommaya reservoir placed under the scalp by a neurosurgeon, with an attached catheter passed through a burr hole in the skull with its tip in a cerebral ventricle. Although investigators have described home care of patients receiving intraspinal analgesics, no report describes the process of transitioning the patient receiving continuous ICV morphine infusion to the home setting.

Bone marrow transplant recipients were randomly assigned to receive morphine by either continuous infusion (32 patients) or self-administration of small boluses (patient-controlled analgesia (PCA), 26 patients) for control of chemoradiotherapy-induced oral mucositis pain. All patients received morphine for a minimum of 9 days and most required morphine for at least 14 days. Patients rated their pain and side-effect intensity daily using visual analogue scales. Patient pain ratings did not differ between the groups although PCA patients used only 53% as much morphine as the continuous infusion group. Tolerance did not develop in the PCA group; in patients receiving continuous infusion morphine dosage continued to increase throughout the study while pain scores remained constant, indicating that tolerance had developed. Nausea, alertness and respiratory rate measurements did not differ between groups. PCA appeared more effective than the hospital staff determined treatment at delivering the least amount of morphine required to produce maximal pain relief. Patients self-administering morphine did not appear to restrict morphine intake in order to minimize opioid side-effects.

Over the past 20 years, increasing attention has been paid to quality-of-life issues in oncology. As the hospice movement has grown in this country, palliative care has developed into an integral part (rather than the antithesis) of comprehensive cancer care. Palliative care must be integrated earlier into the continuum of cancer care, and palliative, symptom-modifying therapy should be provided simultaneously with disease-modifying therapy from diagnosis. The goal of the NCCN palliative care guidelines is to help assure that each patient with cancer experiences the best possible quality of life throughout the illness trajectory. These guidelines are intended to help oncology teams provide the best care possible for their patients with incurable cancer. For the most recent version of the guidelines, please visit NCCN.org

Young and old healthy subjects with indwelling venous cannulae were found to undergo significant diurnal variations in plasma catecholamine levels. Both norepinephrine and epinephrine levels peaked in late morning and reached lowest values at night during sleep. Catecholamine levels were similar during slow wave and rapid eye movement sleep. While epinephrine levels were unaffected by age, norepinephrine levels were greater in older subjects by 28% during the day (at 1100 h; P less than 0.01) and by 75% at night (between 2200--0900 h; P less than 0.01). Older subjects slept less well; they had 90% less stage 4 sleep, 27% less rapid eye movement sleep, and twice as much wakefulness at night (P less than 0.05). These findings raise the possibility that this well known age effect on sleep may be related to increased sympathetic nervous system activity.

Effects of inhaling three levels of nitrous oxide in oxygen on event-related brain potentials (ERPs) and pain report were examined in 10 volunteers undergoing painful electrical stimulation of tooth pulp. Previous work by the authors demonstrated that inhalation of nitrous oxide 33 per cent in oxygen, iv injection of 0.1 mg fentanyl, oral administration of 975 mg aspirin, and electrical acupunctural stimulation all reduced ERP amplitudes obtained a vertex during painful tooth pulp stimulation. The authors report here the demonstration of a dose-response relationship between increasing concentrations of nitrous oxide in oxygen and measures of ERP amplitude and pain report. Subjects inhaled room air, nitrous oxide 25 per cent, 37 per cent, and 50 per cent in oxygen while ERPs were recorded and pain reports were given. The procedure was repeated on three separate days with each subject experiencing all levels of treatment on each day. Analyses of variance revealed that both ERP amplitude and pain report significantly decreased as dosage increased, and a significant linear trend was observed for the positive-going ERP wave-form deflection between 160 and 240 ms. Pain report scores decreased significantly (P less than 0.001) and proportionally as dosage increased, but there was not a significant linear trend. Inhalation of nitrous oxide in oxygen increased peak latency for the negative component at 50 ms and the positive component at 90 ms but not for later components. These outcomes demonstrate that amplitude measures of the vertex ERP obtained with dental dolorimetry correlate consistently with pain and analgesia. Simultaneous assessment of brain electrical activity and subjective report appears to be a useful approach for the assessment of analgesia in humans.

The effects of electrical acupunctural stimulation (2 Hz) on pain judgments and evoked potentials are reported for two experiments using dental dolorimetry. In the first experiment subjects received acupuncture at points located in the same neurologic segment as the test tooth. In the second experiment subjects received acupuncture at points on the hands located on acupuncture meridians. In both instances acupuncture resulted in a reduction in pain intensity and smaller evoked potential amplitudes, but naloxone neither reversed the analgesia nor did it affect the evoked potentials. A pilot study was carried out to determine whether manual rather than electrical stimulation would produce an analgesia reversible by naloxone, but it failed to do so. These findings contribute to the growing evidence that acupunctural stimulation significantly reduces pain sensibility in volunteers undergoing dolorimetric testing, but they do not support the hypothesis that endorphin release is a mechanism by which acupuncture exerts analgesia.

This study was undertaken to determine whether different analgesic treatments result in a common change in the event-related potentials (ERP) elicited during painful dental stimulation. The effects of electrical acupuncture delivered at 2 Hz to LI-4, the opiate fentanyl 0.1 mg i.V., and the inhalation analgesia mixture of 33% nitrous oxide in oxygen were examined in volunteers undergoing painful tooth pulp stimulation. ERPs were recorded at vertex and subjects provided reports of pain intensity. Discriminant function analysis was used to determine which subset of the pain report and ERP variables could best discriminate baseline from treatment conditions without regard to specificity of treatment. Together with pain report, amplitude of the ERP positive deflection at 250 msec was a significant indicator of analgesia across the 3 treatments. Other changes specific to the individual treatments were also observed. Since the 250 msec amplitude measure was not redundant statistically with pain report, the ERP data provided significant new information about analgesia even though pain report was a very sensitive measure. Pain report alone could account for 48% of the variance across treatments while ERP measures alone accounted for 34%.

1. Effects of inhaling nitrous oxide in oxygen were observed in subjects undergoing noxious dental (N=10) or nonnoxious auditory (N=10) stimulation. Evoked potentials (EPs), 100-500 msec poststimulus, were recorded at vertex, and peak-to-peak amplitudes as well as peak latencies were quantified. 2. Both dental and auditory EPs were reduced by 33% nitrous oxide in oxygen concentration and a dose-related effect was seen in the auditory modality when the concentration was increased to 50%. 3. These observations demonstrate that nitrous oxide inhalation has a broad impact on neurophysiological function in addition to behaviorally determined analgesia.

We were unable to demonstrate the reversal of dental acupunctural analgesia following the injection of 0.4 mg naloxone using evoked potential methodology. Since our findings differed from those of Mayer, Price and Rafii who used pain threshold methods, we attempted to replicate their study. Subjects who demonstrated acupunctural analgesia during electrical stimulation of the LI-4 point on the hands received either 1.2 mg naloxone or normal saline under double blind conditions. Pain thresholds elevated by acupuncture failed to reverse when naloxone was given. Review of experimental design issues, other related human subjects research, and animal studies on acupunctural analgesia provided little convincing evidence that endorphins play a significant role in acupunctural analgesia. Because endorphins can be released in response to a Stressor, endorphin presence sometimes correlates with acupunctural treatment in animal studies and some human studies, especially those involving pain patients. The primary analgesia elicited by acupunctural stimulation seems to involve other mechanisms.

Transcutaneous electrical stimulation was employed at two sites in the second trigeminal division to induce dental analgesia in 24 human subjects who were undergoing painful tooth pulp stimulation. Injection of either 1 ml (0.4 mg) naloxone or 1 ml saline was given to each volunteer after 20 minutes of stimulation under double blind conditions. Saline subjects showed no loss of analgesia while naloxone subjects had a partial and significant loss of analgesia. This observation suggests that endogenic opiate-like substances play a role in stimulation-induced analgesia.