Emerging Challenges to the Safe and Effective Use of Methadone for Cancer-Related Pain in Paediatric and Adult Patient Populations

Methadone for Cancer Pain Management in Children: A Review of Literature

Pain associated with cancer is a common feature among children and adolescents. Among opioids, methadone is a unique drug for its multiple mechanisms of action. Methadone is currently underutilized in children. The use of methadone for cancer pain management in children was assessed in a systematic review. Altogether, 141 children receiving methadone were examined, and another 126 children were assessed for QT prolongation. In the clinical studies, modalities of use, dosing, and duration of assessment were highly variable. In general, methadone was effective and well tolerated with a limited tendency for dose increases. QT prolongation was reported in a percentage of patients independently of the dosages or other variables. The majority of studies considered the use of methadone to be safe and effective in children. Despite methadone possessing interesting properties that make this drug unique in a pediatric context, data is limited, and the literature available is based on retrospective studies. Methadone could be an effective, inexpensive, and versatile medication in children with cancer who have pain. This drug deserves more interest and should prompt studies of better quality with a larger number of patients.

Translating Knowledge Into Clinical Practice: A Unique End-of-Life Nursing Education Consortium Teleconferencing Program

For learning to influence change in palliative clinical practice, education needs to be ongoing, incorporating specific interventions targeted to the learner, in a format that enhances knowledge and networking. This novel, online, interactive, case-based educational offering provided a method to allow ongoing integration of palliative care principles for health care professionals who attended the End-of-Life Nursing Education Consortium/Open Medical Institute courses in Salzburg during 2019-2022. Eight monthly teleconferences based on challenging clinical cases allowed discussion between palliative care professionals from 9 countries, serving as a mechanism for deepening theoretical information, allowing incorporation of best practice into the clinical setting, and, ultimately, improving care for all with serious illness. Many of the challenges encountered providing palliative care are universal. Through case vignettes, the group has been able to offer specific interventions, advances in practice, and discussions of approaches toward family and other health care professionals to provide optimal care. The participants report that the opportunity to learn from and support peers in other countries has been a rewarding and emotionally uplifting experience. These discussions were highly rated by participants who strongly voiced that the interactions would change their clinical practice to positively impact patient care.

Intravenous methadone in the management of acute postoperative pain in a chronic cancer pain patient: A case report and review of the literature

Key Clinical Message

The current landscape of literature highlights that there is insufficient well-powered and robust evidence to support the integration of intravenous methadone into current guidelines and frameworks in supporting the pain management of cancer patient with complex pain syndromes. However, there is preliminary evidence, both from the literature as well as this case study that highlights intravenous methadone may be efficaciously and safety used for the management of postoperative pain in cancer patients with chronic pain undergoing operative management. Further research is required to fully elucidate key considerations of integrating this medication into clinical practice including consideration into dosing, opioid conversion, tolerance, and safety.

Abstract

Methadone is a broad-spectrum analgesic with long duration of effect. Its multimodal mechanism of action, such as through effects on mu-opioid receptor and presynaptic N-methyl-D-aspartate receptors, has led to its current use in the management of opioid dependence in the community and in palliative care. These properties however make methadone appealing in the management of postoperative pain, particularly for patients with complex analgesic requirements. We report on an interesting case whereby intravenous methadone was effectively used for postoperative analgesia in a 56-year-old female with complex chronic pain secondary to a mucinous pelvic neoplasm of unclear primary who underwent palliative resection. Further, we review the literature surrounding usage of methadone in this setting to understand current challenges and barriers to implementation of methadone as an analgesia option for chronic pain patients following surgery. To do this, a case report and literature review was conducted in accordance to the CARE case report guidelines. The patient provided written consent for the de-identification and use of their medical information and data for the generation and publication of this case report. Our case report and literature review demonstrate there remains significant heterogeneity, unfamiliarity, and scarce use of intravenous methadone in the perioperative and postoperative space in the management of patients with complex pain regimens such as chronic cancer pain patients. Despite this, our case report and literature review highlight as a broad analgesic, intravenous methadone warrants consideration following more rigorous research and development of safe use guidelines into its use for this purpose.

Comparing National Methadone Equianalgesic Tools

Methadone is an effective analgesic with unique pharmacokinetic and pharmacodynamic variables. There is no national consensus on methadone equianalgesia tools. Our study aimed to compare methadone equianalgesic tools from various national institutions with the primary objective to summarize current practice and secondary objective to determine if a national consensus can be established. Out of 25 institutional methadone equianalgesic tools reviewed, 18 contained sufficient data and were included in this study. Fifteen (15) of the institution evaluated tools utilized a wide variety of dose-dependent modalities for methadone conversion with the hospice and palliative care (HAPC) Consensus method being the most common. Based on the variability of the equianalgesia tools evaluated in this study, we were unable to recommend a consensus methadone conversion method. Further trials exploring methadone equianalgesia beyond our study are needed.

Pain Assessment in Pediatric Patients with Primary Bone Cancer in a Single Site Cohort

Introduction: Pain is the main symptom described in cancer patients. Objective: To assess pain classification and management in pediatric patients with primary bone cancer over time: admission, during treatment and follow-up, and to investigate factors associated with pain classification at the last assessment. Method: Retrospective cohort study of osteosarcoma and Ewing's sarcoma cases in individuals <19 years old treated at a single cancer referral site and followed up by a multidisciplinary team. The primary endpoint was pain score at the last assessment. Secondary outcome: evolution of pharmacological treatment. Results: 142 patients were included. The frequency of pain assessment increased during the study period from 53.5% at admission to 68.3% during treatment and 85.9% in follow-up. Of the patients who had pain assessed, 65.8% had pain at admission and 26.2% at the end of the study. There was an increase in the use of strong opioids and antidepressants. In the last evaluation, 56 patients (39.4%) were at the end-of-life and this was not associated with more pain (p=0.68). Meanwhile, those who had more pain used strong opioids (p=0.01) or steroids (p=0.03). Conclusion: Pain management during treatment resulted in increased use of strong opioids and antidepressants with pain reduction, revealing that pain control is possible. In the last assessment, end-of-life patients no longer had pain and patients with pain were the ones who used strong opioids and steroids at the most, showing the difficulty of pain control in some patients.

Assessing cardiac safety among clients receiving methadone as part of opioid agonist maintenance therapy (OAMT) in Durban, South Africa

Methadone is a recommended medication for opioid agonist maintenance therapy (OAMT). However, methadone can have cardiac side effects. There is limited South African cardiac safety data on methadone.

To describe baseline and 12-month electrocardiographic (ECG) features and cardiac symptomology in people receiving OAMT in Durban, South Africa.

Twelve-lead ECGs were conducted at baseline and 12 months. Clinical interviews were used to assess cardiac symptomatology. Baseline ECG parameters (PR interval, QRS interval, QT and QTc duration, heart rate) were analyzed using descriptive statistics. Baseline and 12-month ECG characteristics were compared using paired T-tests in retained participants. The association between QTc and methadone dose was assessed using Spearman's Rho at 12 months.

Fifty-three clients (51 men, 2 women [median age 29.0]) were initiated on OAMT. Normal baseline ECG variants included 4 (7.5%) with sinus bradycardia and 3 (5.7%) with ST segment elevation. Mean baseline ECG intervals were PR interval: 156 ± 23 ms, QRS duration: 87 ± 9 ms, QT interval: 404 ± 22 ms and QTc interval: 406.9 ± 21.9 ms. At 12 months, 39 participants returned for reassessment (mean methadone dose: 37 ± 8 mg in women; 27 ± 10 mg in men). QTc intervals among male participants increased (406.4 ± 22 to 417 ± 24; p = 0.026 [-19.6; -1.4]). No significant correlation (r = 0.22; p = 0.185) between methadone dose and QTc interval at 12 months, nor reports of adverse cardiac symptomatology, were detected.

Methadone at the doses provided, caused mild and clinically insignificant QTc interval prolongation in men at 12 months. We provide additional cardiac safety data for the use of methadone for OAMT among people with opioid use disorder.

The Burden of Metastatic Cancer-Induced Bone Pain: A Narrative Review

Bone pain is one of the most common forms of pain reported by cancer patients with metastatic disease. We conducted a review of oncology literature to further understand the epidemiology of and treatment approaches for metastatic cancer–induced bone pain and the effect of treatment of painful bone metastases on the patient’s quality of life. Two-thirds of patients with advanced, metastatic, or terminal cancer worldwide experience pain. Cancer pain due to bone metastases is the most common form of pain in patients with advanced disease and has been shown to significantly reduce patients’ quality of life. Treatment options for cancer pain due to bone metastases include nonsteroidal anti-inflammatory drugs, palliative radiation, bisphosphonates, denosumab, and opioids. Therapies including palliative radiation and opioids have strong evidence supporting their efficacy treating cancer pain due to bone metastases; other therapies, like bisphosphonates and denosumab, do not. There is sufficient evidence that patients who experience pain relief after radiation therapy have improved quality of life; however, a substantial proportion are nonresponders. For those still requiring pain management, even with available analgesics, many patients are undertreated for cancer pain due to bone metastases, indicating an unmet need. The studies in this review were not designed to determine why cancer pain due to bone metastases was undertreated. Studies specifically addressing cancer pain due to bone metastases, rather than general cancer pain, are limited. Additional research is needed to determine patient preferences and physician attitudes regarding choice of analgesic for moderate to severe cancer pain due to bone metastases.

Managing Pain and Discomfort in Children with Cancer

PURPOSE OF REVIEW

Approximately 15,600 children are diagnosed with cancer annually. Many of these children have cancer-related pain that improves with cancer treatment, but some develop intractable pain from cancer progression or sequelae from treatment modalities. The purpose of this paper is to provide a critical evaluation of the literature relevant to pain management in children with cancer. We intend to emphasize important and up-to-date findings in pharmacology, interventional pain management, and complementary and alternative medicine.

RECENT FINDINGS

Alternative medications and routes of administration, complementary and alternative medicine techniques, and interventional pain procedures offer possible routes for a multi-pronged pediatric cancer pain management plan, although high-level data is often lacking. To improve pediatric cancer pain management, a multifaceted approach embracing the biopsychosocial model of pain is recommended, incorporating evidence-based pharmacology, complementary and alternative medicine techniques, and if needed, interventional pain procedures.

Old Drug, New Pain. Roles and Challenges of Methadone Therapy in Pediatric Palliative Care: A Systematic Review

BACKGROUND

Pediatric palliative care (PPC) is defined as the prevention and relief from suffering of families and children with life-limiting (LLDs) or life-threatening diseases (LTDs). These patients often experience pain, with morphine being the most widely used drug to treat it. Few studies investigated the role of methadone in PPC patients, although it is considered among the most effective and underutilized drugs in PPC.

OBJECTIVES

Our aim was to evaluate the efficacy, safety, and dosage of methadone in PPC.

METHODS

Between August and October 2021 PubMed, Scopus and the Cochrane Library were searched for studies on the use of methadone in children with LLDs and LTDs. Articles were included if they met the following criteria: published in the last 10 years, English language, patients aged 0-23 years; children enrolled in a PPC center or receiving declared support from a PPC service; reporting of specific data on methadone in interventional trials, observational studies, or case series on >10 patients. The reporting of the article was guided by the PRISMA guidelines, and a critical appraisal of the included studies was performed using the JBI-tool.

RESULTS

After duplicates removal and full-text assessment, four studies were included and another one was added after checking the references of the retrieved papers. All were retrospective, and the literature is concordant in documenting the lack of evidence. A total of 116 children received methadone in PPC. From our review emerges the poor quality of data collection: in only one study pain was assessed with standardized scales. All studies documented the effectiveness of methadone in treating complex pain, either nociceptive or neuropathic. No serious adverse events were reported, with no cases of cardiac arrhythmias.

CONCLUSION

Our results suggest that methadone could represent a suitable strategy for treating pain in PPC. However, the evidence base is insufficient, and further research is warranted.