Shifting views on cancer pain management: a systematic review and network meta-analysis.

CONTEXT: Strong opioids are the cornerstone in the treatment of cancer-related pain. OBJECTIVES: This study aims to compare analgesic effectiveness of different strong opioids for the treatment of cancer-related pain. METHODS: PubMed and Embase were searched for RCTs that compared strong opioids for treatment of cancer-related pain against one another. A network meta-analysis was conducted and the related Surface Under the Cumulative RAnking (SUCRA)-based treatment ranks were calculated. Primary outcome was pain intensity (numerical rating scale (NRS)) and/or the percentage of patients with ≥50% pain reduction, after 1 and 2-4 weeks. RESULTS: Sixteen RCTs (1813 patients) were included. Methadone showed, with a high certainty of evidence, increased ORs for treatment success at 1 week, compared with morphine, buprenorphine, fentanyl, and oxycodone, range 3.230-36.833. Methadone had the highest likelihood to be the treatment of preference (ToP) (SUCRA 0.9720). For fentanyl, ORs were lower, however significant and with high certainty. After 2-4 weeks, methadone again showed the highest likelihood for ToP, however, with moderate certainty and non-significant ORs. The combination of morphine/methadone, compared with morphine, buprenorphine, fentanyl, hydromorphone, methadone, and oxycodone achieved a treatment effect of mean NRS difference after 2-4 weeks between -1.100 and -1.528 and had the highest likelihood for ToP. CONCLUSION: The results suggest that methadone possibly deserves further promotion as first-line treatment for the treatment of cancer-related pain.

Cervical Epidural Anesthesia in the Management of a Patient With Breast Cancer With Cardiac Dysfunction: A Case Report.

As one of the most common cancers in the world, breast cancer management is fraught with difficulties. Modified radical mastectomy (MRM) is one of the surgical procedures that is essential to the treatment of breast cancer. Cardiovascular issues, especially a reduced ejection fraction (EF), make these procedures more complex. Due to their increased vulnerability to adverse cardiac events during surgery, it is imperative to preserve hemodynamic stability and reduce physiological stress responses in these patients. A promising option in this changing field of anesthetic techniques is cervical epidural anesthesia (CEA). It effectively reduces hemodynamic fluctuations frequently linked to general anesthesia while providing analgesia. We report the case of an elderly patient with decreased EF and breast cancer scheduled for an MRM. To ensure the best possible outcomes in complex cases, the case report covers preoperative assessment, anesthesia technique, intraoperative management, and postoperative outcomes. This highlights the critical significance of customizing anesthesia and surgical procedures, informed consent, and meticulous postoperative pain management, and ultimately advocates for the broader implementation of CEA in such settings.

Validity of central pain processing biomarkers for predicting the occurrence of oncological chronic pain: a study protocol.

BACKGROUND: Despite recent improvements in cancer detection and survival rates, managing cancer-related pain remains a significant challenge. Compared to neuropathic and inflammatory pain conditions, cancer pain mechanisms are poorly understood, despite pain being one of the most feared symptoms by cancer patients and significantly impairing their quality of life, daily activities, and social interactions. The objective of this work was to select a panel of biomarkers of central pain processing and modulation and assess their ability to predict chronic pain in patients with cancer using predictive artificial intelligence (AI) algorithms. METHODS: We will perform a prospective longitudinal cohort, multicentric study involving 450 patients with a recent cancer diagnosis. These patients will undergo an in-person assessment at three different time points: pretreatment, 6 months, and 12 months after the first visit. All patients will be assessed through demographic and clinical questionnaires and self-report measures, quantitative sensory testing (QST), and electroencephalography (EEG) evaluations. We will select the variables that best predict the future occurrence of pain using a comprehensive approach that includes clinical, psychosocial, and neurophysiological variables. DISCUSSION: This study aimed to provide evidence regarding the links between poor pain modulation mechanisms at precancer treatment in patients who will later develop chronic pain and to clarify the role of treatment modality (modulated by age, sex and type of cancer) on pain. As a final output, we expect to develop a predictive tool based on AI that can contribute to the anticipation of the future occurrence of pain and help in therapeutic decision making.

The TREK-1 potassium channel is involved in both the analgesic and anti-proliferative effects of riluzole in bone cancer pain.

BACKGROUND: The metastasis of tumors into bone tissue typically leads to intractable pain that is both very disabling and particularly difficult to manage. We investigated here whether riluzole could have beneficial effects for the treatment of prostate cancer-induced bone pain and how it could influence the development of bone metastasis. METHODS: We used a bone pain model induced by intratibial injection of human PC3 prostate cancer cells into male SCID mice treated or not with riluzole administered in drinking water. We also used riluzole in vitro to assess its possible effect on PC3 cell viability and functionality, using patch-clamp. RESULTS: Riluzole had a significant preventive effect on both evoked and spontaneous pain involving the TREK-1 potassium channel. Riluzole did not interfere with PC3-induced bone loss or bone remodeling in vivo. It also significantly decreased PC3 cell viability in vitro. The antiproliferative effect of riluzole is correlated with a TREK-1-dependent membrane hyperpolarization in these cells. CONCLUSION: The present data suggest that riluzole could be very useful to manage evoked and spontaneous hypersensitivity in cancer-induced bone pain and has no significant adverse effect on cancer progression.

Knowledge and practical skills for cancer pain management among nurses on remote islands in Japan and related factors nationwide.

OBJECTIVE: To clarify the knowledge and practical skills needed for cancer pain management among nurses on remote islands in Japan and related factors nationwide. SETTING: Due to geographical factors, nurses working on remote islands in Japan have few opportunities to attend training programs, which makes it difficult to acquire the knowledge and practical skills needed to provide pain management for patients with cancer. METHODS: We conducted a self-administered questionnaire survey regarding knowledge and practical skills in pain management for patients with cancer. DESIGN: Cross-sectional study. PARTICIPANTS: Nurses working in cancer pain care in medical facilities and home care on remote islands throughout Japan. RESULTS: We analysed 128 responses. Regarding knowledge, the average accuracy level was 49.1%. Items with a low accuracy rate included selecting medicine according to the type of pain and the patient's condition. Regarding practice, the items with low scores included analgesics appropriate for the type of pain and relating physical pain to mental, social and spiritual aspects. The most common significant factor in both knowledge and practice was related to postgraduate training. CONCLUSIONS: These findings suggest that to improve the knowledge and practical skills for cancer pain management among nurses on remote islands in Japan, it is necessary to incorporate clinical reasoning into basic education and establish remote education systems and consultation systems with other facilities.

Dangerous Variation or Patient-Centered Care? Palliative Care and Pain Providers' Comfort, Experiences, and Approaches when Treating Cancer Pain With Coexisting Aberrant Behaviors.

BACKGROUND: Patients with cancer-related pain are at high risk for aberrant drug use behaviors (ADB), including self-escalation, diversion and concurrent illicit substance or opioid misuse; however, limited evidence is available to guide opioid prescribing for patients with life-limiting illness and concurrent or suspected ADB. We sought to characterize how specialists evaluate for and manage these high-risk behaviors in patients with cancer-related pain. METHODS: We conducted telephonic semi-structured interviews with palliative care and pain medicine providers. Participants discussed their own comfort and experience level with identifying and managing ADB in patients with life-limiting illness. They were subsequently presented with a series of standardized scenarios and asked to describe their concerns and management strategies. RESULTS: 95 interdisciplinary pain and palliative care specialists were contacted; 37 agreed to participate (38.9%). Analysis of interview contents revealed several central themes: (1) widespread discomfort and anxiety regarding safe and compassionate opioid prescribing for high-risk patients, (2) belief that widely used risk-mitigation tools such as opioid contracts and urine drug screens provided inadequate support for decision-making, and (3) lack of institutional and organizational support and guidance for safe prescribing strategies. Most clinicians reported self-education regarding addiction and alternative prescribing/pain management strategies. Providers varied widely in their willingness to discontinue opioid prescribing in a patient with aberrant behavior and pain associated with life-limiting illness. CONCLUSION: Providers caring for patients demonstrating ADB and cancer-related pain struggle to balance safe prescribing with symptom management. Increased guidance is needed regarding opioid prescribing, monitoring, and discontinuation in high-risk patients.

A Novel Approach in Treating Phantom Limb Pain Using Erector Spinae Plane Block.

Phantom limb pain (PLP) is difficult to control, and patients frequently exhibit inadequate relief from medications or encounter unbearable side effects. We present here a novel application of erector spinae plane (ESP) block to manage PLP. Our patient is a 23-year-old, college student, diagnosed with high-grade osteosarcoma of the right humerus who underwent a right shoulder disarticulation. He reported PLP despite multimodal analgesia postoperatively. An ESP block using a high-frequency linear probe ultrasound was performed. A G23 spinal needle was advanced in-plane toward the right T3 transverse process. After negative aspiration, 20 mL of therapeutic solution containing bupivacaine 0.25%, lidocaine 1%, epinephrine 5 mcg/ml, and 40 mg methylprednisolone was injected. After the procedure, the patient reported that his PLP went down to NRS 1/10. He consistently reported to have an NRS score of 0-1/10 on succeeding consultations despite discontinuation of opioid and pregabalin. In literature, ESP block has been used as a regional technique for shoulder disarticulation surgery and other neuropathic pain conditions, but no account has shown its use for PLP treatment. The procedure was successfully done to alleviate the upper extremity phantom limb pain, significantly reduce analgesic requirements, and improve tolerance of physical therapy and overall quality of life.

ABCB1 genetic polymorphisms affect opioid requirement by altering function of the intestinal P-glycoprotein.

The association between polymorphisms of the human ATP binding cassette subfamily B member 1 (ABCB1) gene and opioid response has attracted intense attention recently. As the ABCB1 gene encodes for the transporter P-glycoprotein in the brain and intestine involved in the pharmacokinetics of opioids, we investigated the effects of ABCB1 genetic polymorphisms on doses of opioids for pain relief and determined which pharmacokinetic process was affected in cancer pain patients. Sixty-eight cancer pain patients admitted for intrathecal therapy (ITT) were included. The association between ABCB1 genetic polymorphisms (C3435T, C1236T, G2677T/A and A61G) and systemic doses of opioids before ITT were investigated. Concentrations of oxycodone in plasma and cerebrospinal fluid (CSF) were determined by HPLC-MS/MS in 17 patients treated with oral oxycodone before ITT, and the influences of ABCB1 genetic polymorphisms on plasma-concentration to oral-dose ratios and CSF-concentration to plasma-concentration ratios of oral oxycodone were further analyzed. ABCB1 C3435T and G2677T/A polymorphisms were significantly associated with systemic doses of opioids before ITT, which coincided with the influences of ABCB1 C3435T and G2677T/A polymorphisms on the ratios of plasma-concentration to oral-dose. However, no significant difference was found in ratios of CSF-concentration to plasma-concentration among ABCB1 SNP genotypes. The present study provided the first evidence that ABCB1 C3435T and G2677T/A polymorphisms affect opioid requirement in cancer pain patients via altering transportation function of P-glycoprotein in the intestine, which will further expand our knowledge about pharmacokinetics of opioids and could contribute to the individualization of opioids use.

Use of Goals in Cancer Pain Management: A Systematic Review.

CONTEXT: Cancer pain is multidimensional and management should be individualized to patient goals. The current standard for pain goal assessment is the personal pain goal (PPG), a numeric rating for tolerable pain intensity. However, the PPG may not accurately capture a personally meaningful goal for tailoring pain management. OBJECTIVES: Identify how pain goals are used in cancer pain management and types of goals researched. METHODS: CINAHL, PsychInfo, and PubMed databases and manual searching were used to locate research or scholarship about cancer pain goals. Authors reviewed titles, abstracts and full text to agree on the final sample. RESULTS: Sixteen articles met inclusion criteria. Study designs included: quality improvement project (1), concept analysis (1), qualitative methods (5), quantitative methods (8), and mixed methods (1). Findings included: goal setting as a key attribute of pain management; achieving personal goals as the outcome of pain management work; qualitative themes discussed personal goals related to pain management; developing a patient pain management resource including a SMART goal; using motivational interviewing to set functional pain goals; PPG assessment was feasible; and achieving PPG equated to having controlled pain when compared to the clinically important difference measure used in research (≥30%). Quantitative studies reported on PPGs only. CONCLUSION: Currently, assessments for cancer pain goals do not include function, activities, moods, medication effects, or safety that patients wish to achieve as a pain management outcome. Development and testing of multidimensional patient pain goals assessments is warranted so that goals can be consistently assessed, documented, and personally meaningful.

Discovery of a CCR2-targeting pepducin therapy for chronic pain.

Targeting the CCL2/CCR2 chemokine axis has been shown to be effective at relieving pain in rodent models of inflammatory and neuropathic pain, therefore representing a promising avenue for the development of non-opioid analgesics. However, clinical trials targeting this receptor for inflammatory conditions and painful neuropathies have failed to meet expectations and have all been discontinued due to lack of efficacy. To overcome the poor selectivity of CCR2 chemokine receptor antagonists, we generated and characterized the function of intracellular cell-penetrating allosteric modulators targeting CCR2, namely pepducins. In vivo, chronic intrathecal administration of the CCR2-selective pepducin PP101 was effective in alleviating neuropathic and bone cancer pain. In the setting of bone metastases, we found that T cells infiltrate dorsal root ganglia (DRG) and induce long-lasting pain hypersensitivity. By acting on CCR2-expressing DRG neurons, PP101 attenuated the altered phenotype of sensory neurons as well as the neuroinflammatory milieu of DRGs, and reduced bone cancer pain by blocking CD4+ and CD8+ T cell infiltration. Notably, PP101 demonstrated its efficacy in targeting the neuropathic component of bone cancer pain, as evidenced by its anti-nociceptive effects in a model of chronic constriction injury of the sciatic nerve. Importantly, PP101-induced reduction of CCR2 signaling in DRGs did not result in deleterious tumor progression or adverse behavioral effects. Thus, targeting neuroimmune crosstalk through allosteric inhibition of CCR2 could represent an effective and safe avenue for the management of chronic pain.

Oxymatrine and Gut Microbiota Modulation: A Potential Therapeutic Strategy for Bone Cancer Pain Management.

Chronic pain often coincides with changes in gut microbiota composition. Yet, the role of gut microbiota in bone cancer pain(BCP) is still not fully understood. This study investigated the role of gut microbiota in BCP and the effect of oxymatrine(OMT) on gut microbiota in BCP. A BCP mice model was developed to assess gut microbiota composition, serum and brain tissue butyric acid levels, and blood-brain barrier(BBB) permeability. Microbiota transplantation was used to restore gut microbiota, and the effect of Clostridium butyricum (C. butyricum) or sodium butyrate(NaB) supplementation on pain-related behaviors and BBB integrity was evaluated. The potential benefits of OMT on gut microbiota composition, PPARγ/COX-2 signaling, BBB integrity, and pain-related behaviors were also explored. BCP significantly altered gut microbiota composition and reduced serum and brain tissue butyric acid levels. Additionally, BBB permeability increased considerably in the BCP group compared to sham and control mice. Microbiota transplantation, as well as C. butyricum or NaB supplementation, ameliorated pain-related behaviors and BBB integrity; the supplementation of C. butyricum or NaB boosted brain tight junction protein expression, potentially through modulating PPARγ/COX-2 signaling. OMT influenced gut microbiota composition and regulated PPARγ/COX-2 signaling in the BCP model, improving pain-related behaviors and BBB integrity. BCP affects gut microbiota composition and butyric acid levels. Modulating gut microbiota and butyric acid levels through transplantation or supplementation may alleviate BCP. OMT shows potential as a treatment by altering gut microbiota composition and regulating PPARγ/COX-2 signaling. These findings provide new insights into BCP pathophysiology and possible treatments. PERSPECTIVE: This study explores the impact of gut microbiota on bone cancer pain (BCP). Microbiota transplantation alleviates BCP and enhances BBB integrity. Also, Clostridium butyricum or sodium butyrate improves BBB via PPARγ/COX-2. Oxymatrine (OMT), a BCP treatment, modifies microbiota by regulating PPARγ/COX-2, in turn improving pain and BBB integrity. These findings suggest a therapeutic approach, emphasizing clinical relevance in targeting gut microbiota and restoring butyric acid levels.

Spinal cord stimulation attenuates paclitaxel-induced gait impairment and mechanical hypersensitivity via peripheral neuroprotective mechanisms in tumor-bearing rats.

BACKGROUND: Taxanes such as paclitaxel (PTX) induce dose-dependent chemotherapy-induced peripheral neuropathy (CIPN), which is associated with debilitating chronic pain and gait impairment. Increased macrophage-related proinflammatory activities have been reported to mediate the development and maintenance of neuropathic pain. While spinal cord stimulation (SCS) has been used for a number of pain conditions, the mechanisms supporting its use for CIPN remain to be elucidated. Thus, we aimed to examine whether SCS can attenuate Schwann cell-mediated and macrophage-mediated neuroinflammation in the sciatic nerve of Rowlette Nude (RNU) rats with PTX-induced gait impairment and mechanical hypersensitivity. METHODS: Adult male tumor-bearing RNU rats were used for this study examining PTX treatment and SCS. Gait and mechanical hypersensitivity were assessed weekly. Cytokines, gene expression, macrophage infiltration and polarisation, nerve morphology and Schwann cells were examined in sciatic nerves using multiplex immunoassay, bulk RNA sequencing, histochemistry and immunohistochemistry techniques. RESULTS: SCS (50 Hz, 0.2 milliseconds, 80% motor threshold) attenuated the development of mechanical hypersensitivity (20.93±0.80 vs 12.23±2.71 grams, p<0.0096) and temporal gait impairment [swing (90.41±7.03 vs 117.27±9.71%, p<0.0076), and single stance times (94.92±3.62 vs 112.75±7.27%, p<0.0245)] induced by PTX (SCS+PTX+Tumor vs Sham SCS+PTX+Tumor). SCS also attenuated the reduction in Schwann cells, myelin thickness and increased the concentration of anti-inflammatory cytokine interleukin (IL)-10. Bulk RNA sequencing revealed differential gene expression after SCS, with 607 (59.2%) genes upregulated while 418 (40.8%) genes were downregulated. Notably, genes related to anti-inflammatory cytokines and neuronal growth were upregulated, while genes related to proinflammatory-promoting genes, increased M2γ polarisation and decreased macrophage infiltration and Schwann cell loss were downregulated. CONCLUSION: SCS may attenuate PTX-induced pain and temporal gait impairment, which may be partly attributed to decreases in Schwann cell loss and macrophage-mediated neuroinflammation in sciatic nerves.

The Effects of WeChat-Based Teach-Back Health Education on Patients With Advanced Cancer Pain.

BACKGROUND: Providing effective health education is essential for patients with cancer-related pain. One solution is leveraging instant messaging tools for teach-back health education. OBJECTIVES: This study investigated the effects of WeChat-based teach-back health education on patients with advanced cancer who underwent patient-controlled intrathecal analgesia implantation and used hydromorphone. METHODS: This retrospective study evaluated 150 hospitalized patients with advanced cancer pain. Patients were classified into a conventional health education group (N = 50) and a teach-back group (N = 100) based on whether they received WeChat-based teach-back health education. Pain was rated using a numeric rating scale, and sleep quality was measured using the Pittsburgh Sleep Quality Index at one, two, and three months postdischarge. FINDINGS: Patients who received remote teach-back health education better managed their pain. Data also demonstrated improvements in patients' sleep quality and caregiver satisfaction, and reductions in the occurrence of adverse reactions.

The voices of breast cancer survivors with chronic pain: A qualitative thematic analysis of patients' challenges to pain management.

OBJECTIVES: Recognizing the limitations of the current pain therapies, the study aimed to explore the unique needs and obstacles related to pain management in Breast Cancer Survivors (BCs) with Chronic Pain (CP). METHODS: 4 focus groups were conducted involving 17 BCs with CP (Mage = 51, SD = 7.99) with varying pain intensities. Thematic analysis was applied to transcribed discussions. FINDINGS: Three key themes emerged: (1) Challenges to pain management, including "Doctor-patients communications barriers" and "Contextual and societal barriers"; (2) Self-management needs, encompassing "Psycho-social support," "Care-related needs," and "Shared decision-making"; (3) Treatment preferences and perceptions of pain management, with subthemes like "Treatment preferences," "Institution preference," and "Decision role perception." CONCLUSIONS: This study emphasizes tailored support systems targeting patient hesitancy, countering pain normalization, and addressing healthcare providers' attitudes. It underscores the importance of integrating caregiver and peer support. Findings advocate refining healthcare provider education, adopting a comprehensive multidisciplinary approach, and strategically incorporating eHealth tools into such care.

Application of a WeChat Mini Program to provide pharmaceutical care for cancer pain patients: A randomized controlled trial.

Objective: This study aimed to develop an individual WeChat Mini Program to provide pharmaceutical care to better manage cancer pain patients and to evaluate its feasibility and the differences in analgesic efficacy, medication adherence and safety versus conventional pharmacy interventions. Methods: In this parallel randomized clinical trial, 42 cancer pain patients were equally allocated into the experimental group and the control group. The experimental group received individualized pharmaceutical care based on the "Yao Nin You Wo" WeChat Mini Program, while the control group received conventional care during the 4-week period. Main outcomes contained pain scores, medication adherence, incidences and relief rates of breakthrough pain, and incidences of adverse events. Relief rates of pain were also calculated according to pain scores. Results: At the beginning of intervention, none of the pain scores and medication adherence showed relevant differences between the two groups (all P > .05). After intervention, the experimental group had significantly lower pain scores compared to the control group (P = .003). Breakthrough pain of both groups was alleviate; not only the incidence of breakthrough pain considerably was lower at 4 weeks than at baseline, but the relief rate of breakthrough in the experimental group was higher than that in the control group. Compared with the control group, the medication adherence rate of the experimental group was significantly improved (P = .02). Types of adverse events that happened in experimental and groups were similar, but the total incidence of adverse events in the experimental group was lower than that in the control group. Conclusions: WeChat Mini Program is a useful and facilitative tool with the potential to improve cancer pain self-management ability in discharged patients. In addition, pharmacists could play a key role through the Mini Program to connect with patients successfully by providing personalized pharmaceutical services.

Functional role of P2X7 purinergic receptor in cancer and cancer-related pain.

Numerous studies have revealed that the ATP-gated ion channel purinergic 2X7 receptor (P2X7R) plays an important role in tumor progression and the pathogenesis of cancer pain. P2X7R requires activation by extracellular ATP to perform its regulatory role functions. During tumor development or cancer-induced pain, ATP is released from tumor cells or other cells in the tumor microenvironment (such as tumor-associated immune cells), which activates P2X7R, opens ion channels on the cell membrane, affects intracellular molecular metabolism, and regulates the activity of tumor cells. Furthermore, peripheral organs and receptors can be damaged during tumor progression, and P2X7R expression in nerve cells (such as microglia) is significantly upregulated, enhancing sensory afferent information, sensitizing the central nervous system, and inducing or exacerbating pain. These findings reveal that the ATP-P2X7R signaling axis plays a key regulatory role in the pathogenesis of tumors and cancer pain and also has a therapeutic role. Accordingly, in this study, we explored the role of P2X7R in tumors and cancer pain, discussed the pharmacological properties of inhibiting P2X7R activity (such as the use of antagonists) or blocking its expression in the treatment of tumor and cancer pain, and provided an important evidence for the treatment of both in the future.

Managing Severe Cancer Pain with Oxycodone/Naloxone Treatment: A Literature Review Update.

Severe cancer pain substantially affects patients' quality of life, increasing the burden of the disease and reducing the disability-adjusted life years. Although opioid analgesics are effective, they may induce opioid-induced bowel dysfunction (OIBD). Oxycodone/naloxone combination therapy has emerged as a promising approach to mitigate opioid-induced constipation (OIC) while providing effective pain relief. This review provides an updated analysis of the literature of the last decade regarding the use of oxycodone/naloxone in the management of severe cancer pain. Through a comprehensive search of databases, studies focusing on the efficacy, safety, and patient experience of oxycodone/naloxone's prolonged release in severe cancer pain management were identified. Furthermore, the literature discusses the mechanism of action of naloxone in mitigating OIC without compromising opioid analgesia. Overall, the evidence suggests that oxycodone/naloxone combination therapy offers a valuable option for effectively managing severe cancer pain while minimizing opioid-induced constipation, thereby improving patients' quality of life. However, further research is needed to optimize dosing regimens, evaluate long-term safety, and assess patient outcomes in diverse cancer populations.

Buprenorphine Use for Analgesia in Palliative Care.

Buprenorphine is a semi-synthetic long-acting partial µ-opioid receptor (MOR) agonist that can be used for chronic pain as a sublingual tablet, transdermal patch (Butrans®), or a buccal film (Belbuca®). Buprenorphine's unique high receptor binding affinity and slow dissociation at the MOR allow for effective analgesia while offering less adverse effects compared to a full agonist opioid, in particular, less concern for respiratory depression and constipation. It is underused in chronic pain and palliative care due to misconceptions and stigma from its use in opioid use disorder (OUD). This case report discusses the unique pharmacology of buprenorphine, including its advantages, disadvantages, available formulations, drug-drug interactions, initiation and conversion strategies, and identifies ideal populations for use, especially within the palliative care patient population.

Image Guided Energy Ablation for Palliation of Painful Bony Metastases - A Systematic Review.

PURPOSE: To analyze the effectiveness of image-guided energy ablation techniques with and without concurrent therapies in providing palliative pain relief in patients with bone metastases. MATERIALS AND METHODS: OVID Embase, OVID Medline, and Pubmed were searched from inception to April 14th, 2023 using search terms relating to bone lesions and MeSH terms regarding ablation therapy. English peer-reviewed primary articles were included that reported pain scores following image-guided energy-based ablation of bone metastases. Exclusion criteria included 1) non-palliative treatment, 2) pain scores associated with specific treatment modalities not reported, and 3) non-metastatic bone lesions. Mean percentage reduction in pain score was calculated. RESULTS: 1396 studies were screened and 54 were included. All but one study demonstrated decreased pain scores at final follow-up. Mean reduction in pain scores at final follow-up were 49% for radiofrequency ablation (RFA), 58% for radiofrequency ablation and adjunct (RFA-A), 54% for cryoablation (CA), 72% for cryoablation and adjunct (CA-A), 48% for microwave ablation (MWA), 81% for microwave ablation and adjunct (MWA-A), and 64% for high-intensity focused ultrasound (HIFU). Post-procedural adverse event rates were 4.9% for RFA, 34.8% for RFA-A, 9.6% for CA, 12.0% for CA-A, 48.9% for MWA, 33.5% for MWA-A and 17.0% for HIFU. CONCLUSION: Image-guided energy ablation demonstrated consistently strong reduction in pain across all modalities, with variable post-procedural adverse event rates. Due to heterogeneity of included studies, quantitative analysis was not appropriate. Future primary research should focus on creating consistent prospective studies with established statistical power, explicit documentation and comparison to other techniques.