A retrospective study on the use of oral morphine in cancer pain

Management of cancer-related pain

Patients and families struggling with cancer fear pain more than any other physical symptom. There are also significant barriers to optimal pain management in the emergency setting, including lack of knowledge, inexperienced clinicians, myths about addiction, and fears of complications after discharge. In this article, we review the assessment and management options for cancer-related pain based on the World Health Organization (WHO) 3-step approach.

Management of cancer-related pain

Patients and families struggling with cancer fear pain more than any other physical symptom. There are also significant barriers to optimal pain management in the emergency setting, including lack of knowledge, inexperienced clinicians, myths about addiction, and fears of complications after discharge. In this article, we review the assessment and management options for cancer-related pain based on the World Health Organization (WHO) 3-step approach.

Morphine-methadone opioid rotation in cancer patients: analysis of dose ratio predicting factors

The dose ratio that is effective when switching opioid therapy from morphine to methadone in cancer patients varies widely. There are no conclusive data explaining the source of this variability. We analyzed 54 cancer patients undergoing opioid rotation to clarify those factors that influenced the morphine/methadone dose ratio (MMEDR) at Day 10 after the switch. Reasons for switching were uncontrolled pain (10 patients) or side effects (with or without pain, 44 patients). Initial MMEDR was 5:1 or 10:1 (82% or 18% of patients, respectively). Multivariate regression analysis was used to identify the demographic, cancer-related, and treatment-related variables that were potential predictors of MMEDR. Median previous morphine dose for the entire sample was 220 mg/day (range: 30-1000 mg/day). The stable MMEDR median was 5:1 (range: 2:1-15:1). In the univariate analysis, reasons for opioid rotation, age, and previous morphine doses were associated with MMEDR. Multiple linear regression analysis showed that only the reason for switching (pain vs. side effects; P<0.001) and previous morphine doses (lower vs. upper to 300 mg/day; P<0.001) were associated with MMEDR. From this analysis, the MMEDRs for patients rotated for side effects at 300 mg/day or more or less than 300 mg/day of morphine were 9.1:1 or 5.6:1, respectively, and the MMEDRs for those switched for pain at 300 mg/day or more or less than 300 mg/day of morphine were 4.9:1 or 3:1, respectively. Both the reasons for opioid rotation and previous morphine doses are predictive factors and should be used to select the MMEDR more accurately.

Prevalence of pain in patients with cancer: a systematic review of the past 40 years

BACKGROUND

Despite the abundant literature on this topic, accurate prevalence estimates of pain in cancer patients are not available. We investigated the prevalence of pain in cancer patients according to the different disease stages and types of cancer.

PATIENTS AND METHODS

A systematic review of the literature was conducted. An instrument especially designed for judging prevalence studies on their methodological quality was used. Methodologically acceptable articles were used in the meta-analyses.

RESULTS

Fifty-two studies were used in the meta-analysis. Pooled prevalence rates of pain were calculated for four subgroups: (i) studies including patients after curative treatment, 33% [95% confidence interval (CI) 21% to 46%]; (ii) studies including patients under anticancer treatment: 59% (CI 44% to 73%); (iii) studies including patients characterised as advanced/metastatic/terminal disease, 64% (CI 58% to 69%) and (iii) studies including patients at all disease stages, 53% (CI 43% to 63%). Of the patients with pain more than one-third graded their pain as moderate or severe. Pooled prevalence of pain was >50% in all cancer types with the highest prevalence in head/neck cancer patients (70%; 95% CI 51% to 88%).

CONCLUSION

Despite the clear World Health Organisation recommendations, cancer pain still is a major problem.

Incidence of Weak Opioids Adverse Events in the Management of Cancer Pain: A Double-Blind Comparative Trial

With the objective of comparing incidence of adverse events of the opioids codeine, hydrocodone, and tramadol in the relief of cancer pain, we conducted a randomized controlled trial in which patients with cancer were randomly assigned according to a computer-generated schedule to receive one of the three opioids. Of the 177 patients who participated, 62 patients received hydrocodone, 59 patients received codeine, and 56 patients received tramadol. The pain experienced by the participants originated most frequently from the stomach, breast, or prostate gland and was classified as either somatic (33%), visceral (52%), mixed (6%), or neuropathic (9%). At the first visit, 60% of the patients described their pain intensity as moderate (4-6/10), with the remaining 40% of the patients describing their pain as severe (7-10/10). The symptoms most associated with pain were weakness, insomnia. and anorexia. In 77% of the total number of cases, the patient was aware of his/her diagnosis prior to admittance to the palliative care unit. Of the total number of cases, 57% fell in the age range of 60-89 years old and 50% of the participants were female. No significant statistical difference in the analgesic efficacy of the three opioids was found (p: 0.69; chi(2): 0.73). Use of tramadol produced higher rates of adverse events than codeine and hydrocodone: vomiting, dizziness, loss of appetite, and weakness (p < 0.05).

Pharmacological Management of Cancer Pain in the Elderly

Existing studies indicate a high prevalence rate and poor management of cancer pain in the elderly. Pain is often considered an expected concomitant of aging, and older patients are considered more sensitive to opioids. Despite the well known pharmacokinetic changes in the elderly, the complex network of factors involved in the opioid response make the evaluation of a single element, such as age, more difficult. Notwithstanding such difficulties, appropriate analgesic treatment is able to control cancer pain in the elderly in most cases. Skills necessary to optimise pain control in older cancer patients include the ability to objectively assess functional age (not necessarily related to chronological age since the rate of decline is variable), understand the impact of coexisting conditions, carefully manage the numbers and types of drugs taken at the same time and adequately communicate with patients and relatives. The most common treatment of cancer pain consists of the use of regularly given oral analgesics. The elderly are at increased risk of developing toxicity from NSAIDs, and the overall safety of these drugs in frail elderly patients should be considered. When older patients have clear contraindications to NSAIDs, manifest signs of toxicity from these agents, or find that pain is no longer controlled with this class of drugs, opioids should be started. A variety of opioids are available, and they differ widely with respect to analgesic potency and adverse effects among the elderly. Although the aged population requires lower doses of opioids, only careful titration based on individual response can ensure the appropriate response to clinical demand. Elderly patients are potentially more likely to be affected by opioid toxicity because of the physiological changes associated with aging. Nevertheless, appropriate dosage and administration may limit these risks. Cancer patients with pain who do not respond to increasing doses of opioids because they develop adverse effects before achieving acceptable analgesia may be switched to alternative opioids. Despite the favourable effects reported with opioid switching, monitoring is crucial, particularly in the elderly or patients who are switched from high doses of opioids. Adjuvant analgesics, including antidepressants, antiepileptics, corticosteroids and bisphosphonates may help in the treatment of certain types of chronic pain. With an appropriate and careful approach, it should be possible to reduce or eliminate unrelieved cancer pain in most elderly patients and, consequently, to enhance their quality of life. Older patients with cancer should be continuously assessed for cancer pain, both before and after analgesic treatment.

The terminal cancer patient: effects of age, gender, and primary tumor site on opioid dose

OBJECTIVE

The objective of the current study is to describe correlations between age, gender, and primary cancer site and sustained-release opioid doses prescribed for hospice patients at the end of life.

PATIENTS AND SETTING

This study included all 7,201 hospice patients referred to a North American palliative care specialty pharmacy with the primary diagnosis of cancer and who were prescribed transdermal fentanyl, sustained-release oral morphine, or sustained-release oxycodone.

DESIGN

This is a retrospective analysis of the final sustained-release morphine, oxycodone, or transdermal fentanyl doses prescribed to cancer patients, according to pharmacy records. Comparisons between sex and age group were performed with chi-square tests. Mann-Whitney U tests were used to compare mean doses between the sexes. Analyses of covariance (ANCOVA) were used to compare opioid doses between genders and among primary cancer sites while controlling for age.

RESULTS

The inverse association between age group and dose was highly significant. For example, final opioid doses </=120 mg/day oral morphine equivalent were prescribed for only 46.4% of patients between 40 and 49 years of age compared with 86.4% of patients 90 years of age and older. An ANCOVA on the largest non-sex-related diagnoses found primary tumor site and patient age, but not gender, to be associated with sustained-release opioid dose.

CONCLUSIONS

Both primary tumor site and patient age were associated with final opioid dose. Further investigation is warranted to determine which primary tumor sites are associated with unusually high opioid doses and may highlight the need to optimize adjuvant medication therapy if neuropathic and/or inflammatory pain mechanisms are involved and to refer to pain specialists when appropriate.

Side effects of morphine administration in cancer patients

According to the World Health Organization (WHO) guidelines, oral morphine is the first choice drug for treating moderate to severe cancer-related pain. The fear of the side effects caused by this drug and the scarce information about prevention and management of these effects are the main reasons for the underuse of morphine. The aim of this paper is to provide a review of the literature on the side effects most frequently present both in the titration phase and during chronic administration of oral morphine and to describe the appropriate treatment.

Pain management in patients with pancreatic carcinoma

Pancreatic cancer has a very poor prognosis and is often associated with severe pain. A variety of pain syndromes and pain pathophysiologies can be identified. Information about the analgesic efficacy of available oncological treatments is very limited, but the available data suggest that pharmacological and non-pharmacological approaches can be effective in the majority of cases. Guidelines have been developed for drug administration that emphasize indications, selection of routes, optimal dosing, and side effect treatment. Celiac plexus block can be considered for a subgroup of patients who fail to benefit from drug therapy. Optimally, pain management should be provided within a broader model of palliative care, which can address the many problems associated with this challenging disease.

Hospice and palliative care

The emergence of AIDS and the aging of the population, with the numerous malignant and debilitating maladies associated with growing older, have focused attention on the provision of cost-effective quality care by hospice and palliative care programs. Hospice and palliative care is a venerated system of care, which uses an interdisciplinary approach to address the medical, psychosocial, and spiritual issues that arise in the treatment of terminally ill patients. This interdisciplinary stratagem for symptom control is necessary to ensure that dying patients and their families are afforded dignity and quality of life through death and the period of familial bereavement. Although death is dominant in palliative situations, terminal care requires an affirmation of life and a recognition that dying is not an aberration of medical care but a natural and normal process. Palliative care, however, also requires a personal acceptance of death and an acknowledgment that dying does not denote a failure to provide good medical care but, rather, calls for an acquiescence that curative treatment is no longer feasible. Accordingly, the terminal state is an integral process and a time to reconcile differences so that patient and family may accept death with a minimum of physical, spiritual, and psychosocial anguish. This article discusses the various precepts cardinal to hospice and palliative care, including the philosophy of terminal care, the management of pain, the adverse effects of analgesic medications, the management of nonpain symptoms, the use of terminal sedation, and the stages of familial bereavement.

Randomized evaluation of controlled-release codeine and placebo in chronic cancer pain

Codeine is widely used in combination with acetaminophen and aspirin for the management of mild to moderate pain. However, there are few controlled clinical trials of single-entity codeine in chronic cancer pain. The purpose of this study was to evaluate the clinical efficacy and safety of controlled-release codeine given every 12 hr in patients with cancer pain. Thirty-five patients with chronic cancer pain were randomized in a double-blind crossover study to controlled-release (CR) codeine or placebo, for 7 days each. Pain intensity was assessed at 0800 hr and 2000 hr using a visual analogue scale (VAS) and a five-point categorical scale, and the use of "rescue" acetaminophen-plus-codeine (300 mg/30 mg every 4 hr as needed) was recorded. Thirty patients completed the study (17 male, 13 female; mean age, 64.4 +/- 9.8 years) with a mean daily CR codeine dose of 277 +/- 77 mg (range, 200-400 mg). CR codeine treatment resulted in significantly lower overall VAS pain intensity scores (22 +/- 18 mm versus 36 +/- 20 mm, P = 0.0001), categorical pain intensity scores (1.2 +/- 0.8 versus 1.8 +/- 0.8, P = 0.0001), and pain scores when assessed by day of treatment and by time of day. Daily "rescue" analgesic consumption was significantly lower on CR codeine, compared to placebo treatment (2.2 +/- 2.3 versus 4.6 +/- 2.8 tablets per day, P = 0.0001). Both patients and investigators preferred CR codeine to placebo (80% versus 3%, P = 0.0014 and 73% versus 7%, P = 0.0160, respectively). These data indicate that CR codeine, given every 12 hr results in significant reductions in pain intensity and the use of "rescue" acetaminophen-plus-codeine in patients with cancer pain. CR codeine provides the benefits of a flexible single entity codeine formulation and the convenience of 12-hr duration of action, which allows patients uninterrupted sleep and improved compliance.

Efficacy of controlled-release codeine in chronic non-malignant pain: a randomized, placebo-controlled clinical trial

Treatment decisions for the use of opioid analgesics in chronic non-malignant pain are based primarily on survey data, as evidence from well-controlled clinical trials has been lacking. Forty-six patients with chronic non-malignant pain were enrolled in a randomized, double-blind, placebo-controlled evaluation of controlled-release (CR) codeine. Following a 3-7-day diary familiarization period, patients were randomly assigned to 7 days of treatment each with CR codeine q12h or placebo. The CR codeine dose was determined from the consumption of acetaminophen+codeine in the 7 days preceding the study. During both phases, breakthrough pain was treated with acetaminophen+codeine every 4 h as required. Pain intensity was assessed at 08:00 h and 20:00 h using a visual analogue scale (VAS) and a 5-point categorical scale, and rescue analgesic consumption was recorded at the time of use. Thirty patients (17 female, 13 male; mean age: 55.1 +/- 13.4 years) completed the study and were treated with a mean daily CR codeine dose of 273 +/- 78 mg (range: 200-400 mg). CR codeine treatment resulted in significantly lower overall VAS pain intensity scores (35 +/- 18 vs. 49 +/- 16, P = 0.0001), categorical pain intensity scores (1.7 +/- 0.6 vs. 2.2 +/- 0.6, P = 0.0001), and in pain scores by day of treatment and by time of day. Daily rescue analgesic consumption was significantly lower on CR codeine, relative to placebo treatment (3.6 +/- 3.5 vs. 6.1 +/- 3.2 tablets/day, P = 0.0001). There was also a significant reduction in the Pain Disability Index (PDI) on CR codeine, compared to placebo (25.0 +/- 7.7 vs. 35.1 +/- 8.2, P = 0.0001). Patients' and investigators' blinded treatment preference was significantly in favor of CR codeine, relative to placebo (73% vs. 10%, P = 0.0160 and 80% vs. 7%, P = 0.0014, respectively). The incidence of nausea was significantly higher on CR codeine than on placebo (32.6% vs. 11.9%, P = 0.013). Ninety-three percent of patients completing the study requested long-term, open-label treatment with CR codeine. Pain intensity scores at the completion of 19 weeks of long-term evaluation were comparable to those during the double-blind CR codeine treatment. We conclude that treatment with CR codeine results in reduced pain and pain-related disability in patients with chronic non-malignant pain.

Controversies in the long-term management of analgesic therapy in patients with advanced cancer

The management of pain in the patient with advanced cancer requires comprehensive assessment and expertise in the application of many therapeutic techniques. Given the complexity of the problems posed by these patients, it is not surprising that most aspects of palliative care derive from personal anecdote and clinical consensus, rather than well-defined guidelines based on research findings. In the absence of such guidelines, unresolved issues and controversies abound. This review discusses some of the most important of these topics, which range from the overall system of care and quality of assessment to the specifics of pharmacotherapy and other modalities of treatment. In so doing, the rationale for some of the accepted clinical approaches can be clarified, others that are as yet little known can be highlighted, and the issues most in need of further investigation can be defined.

Character of terminal illness in the advanced cancer patient: pain and other symptoms during the last four weeks of life

There is a great variability among advanced cancer patients in the experience of symptoms and their impact on life's activities. A subgroup of difficult patients particularly tax the clinical skills and compassion of practitioners. Although the need for information about these patients is evident, their characteristics have not been explored heretofore. We describe our experience with such patients, a group referred to the Supportive Care Program of the Pain Service at Memorial Sloan-Kettering Cancer Center. Prevalence of pain and other symptoms, patterns of opioid use and routes of drug administration, and the prevalence of suicidal ideation and requests for euthanasia are discussed.

Experience with oral morphine for cancer pain relief

The authors report a prospective survey of 88 patients with cancer pain who were treated with oral morphine solution during a period of 140 days at the Pain Relief Unit, Kidwai Memorial Institute of Oncology, Bangalore. A high percentage of pain relief was achieved at the end of the first week of titrated therapy; relief was maintained at satisfactory levels throughout the study period in a majority of patients (86%). Interruption of oral morphine administration was necessitated by intractable vomiting in two patients. The majority of patients (65%) did not manifest any side effects, and appropriate medication successfully managed those who did. Oral morphine therapy for cancer pain offers effective pain relief with minimal side effects in the majority of patients.

Clinical observations on controlled-release morphine in cancer pain

The authors report the data from two studies on the use of controlled-release morphine sulphate tablets for cancer pain relief. This preparation allows just two administrations per day, in comparison with immediate release oral aqueous morphine solution. The first study, a randomized trial carried out on 70 patients suffering from advanced cancer pain, evaluated the analgesic efficacy and side effects of this drug. The second, an open study of 113 patients, assessed analgesic efficacy, incidence of side effects, and the effects of age on dose. The analgesia provided by controlled-release morphine administration proved to be superimposable to those of the oral aqueous morphine solution. Moreover, the use of controlled-release morphine was associated with a statistically significant reduction of some side effects. Ninety-one percent of patients needed controlled-release morphine every 12 hr, while 9% required it every 8 hr.

Cancer pain. Epidemiology and syndromes

Medical practitioners face the challenge of assuring that pain management has a central place in the treatment of patients with cancer. To meet this challenge, they must understand the prevalence of pain in cancer patients, the frequency with which cancer pain goes untreated or is inadequately managed, and the numerous causes and manifestations of cancer pain. With the goal of contributing to this understanding, this article summarizes the current knowledge about the epidemiology of cancer pain and its syndromes.

Oral controlled-release morphine sulfate. Analgesic efficacy and side effects of a 100-mg tablet in cancer pain patients

Fifty-one cancer pain patients with limited opioid exposure participated in a randomized, double-blind, repeated-dose, parallel-group comparison of two dosage strengths of the controlled-release morphine preparation, MS Contin tablets (The Purdue Frederick Company, Norwalk, CT). The patients were first stabilized on immediate-release oral morphine 30 mg every 4 hours, with 15 mg available every 2 hours as needed for breakthrough pain ("rescue" dose). Each patient then received either one 100 mg MS Contin tablet or three 30-mg MS Contin tablets every 12 hours, with rescue medication as needed, for 3 days. Analysis of study power revealed sufficient sensitivity to detect clinically relevant differences in pain intensity and use of rescue medication. The two tablet strengths yielded similar pain relief, use of rescue medication, and frequency of side effects. In addition, pain and use of rescue medication did not change from the beginning to the end of the 12-hour dosing intervals in either group. In the study population as a whole, pain intensity was lower and total morphine intake higher during the period on controlled-release morphine. These data establish comparable analgesic efficacy and side effect potential of these two dosage strengths and confirm a 12-hour duration of effect for both. The improved analgesia on the controlled-release morphine may be attributable to increased consumption of drug resulting from improved compliance.